dinoprost and Abortion--Veterinary

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Milk; Parity; Pregnancy; Progesterone

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Progesterone

The objective of this review is to evaluate the effectiveness of using pharmacological compounds on reproductive outcomes, particularly litter size, in North American swine. While the opportunity to improve reproduction in North American pigs exists, numerous hurdles need to be overcome in order to achieve measureable results. In the swine industry, the majority of piglet losses are incurred during pregnancy and around farrowing. Over the last 20 years, a reduction in losses has been achieved through genetic selection and nutritional management; however, these topics are the focus of other reviews. This review will evaluate attempts to improve litter size by reducing losses at various stages of the reproductive process, from the time of conception to the time of farrowing, using pharmacological compounds. Generally, these compounds are used to either alter physiological processes related to fertilization, embryonic attachment or uterine capacity, etc., or to facilitate management aspects of the breeding females such as inducing parturition. Although some of the pharmacological agents reviewed here show some positive effects on improving reproductive parameters, the inconsistent results and associated risks usually outweigh the benefits gained. Thus, at the present time, the use of pharmacological agents to enhance reproduction in North American swine may only be recommended for herds with low fertility and presents an avenue of research that could be further explored.

Topics: Abortion, Veterinary; Animal Nutritional Physiological Phenomena; Animals; Breeding; Dinoprost; Estradiol; Female; Growth Hormone; Insemination, Artificial; Litter Size; North America; Placenta; Pregnancy; Pregnancy Outcome; Progesterone; Reproduction; Selection, Genetic; Sus scrofa; Swine; Swine Diseases; Transforming Growth Factor beta1; Uterus

Natural PGF administered at a dose of at least 250 micrograms/kg twice daily subcutaneously for at least 4 days starting no earlier than day 5 of cytologic diestrus induces luteolysis and pregnancy termination in the mated bitch. The resulting shortening of the luteal phase is associated with a shortening of the interestrous interval from 1 to 4 months. Bitches treated with PGF show emesis, diarrhea, and panting within 5 minutes and transient hypothermia which lasts 2 to 3 hours but generally have no further reaction. Bitches with cardiac or respiratory dysfunctions are not considered safe patients for early pregnancy termination with PGF because of the cardiovascular effects of this drug. Bitches treated with this regime early in diestrus resorb their conceptuses; those treated after days 35 to 40 show clinical abortion of viable fetuses.

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Corpus Luteum; Dinoprost; Dog Diseases; Dogs; Estrus; Female; Fetal Death; Muscle, Smooth; Pregnancy

Two experiments were conducted to compare, follicle diameter (FD) on Day -1, corpus luteum (CL) area on Day 7, progesterone (P4) concentration on Day 7 and 18, pregnancy per timed artificial insemination (TAI) on Day 30, and pregnancy loss (PL) between Days 30 and 60 after TAI (TAI, Day 0) using two different synchronization protocols. In Experiment 1, Angus cows (n = 1148) were randomly assigned to either 7-d progesterone CO-Synch (7-d CO-Synch) or 8-d progesterone + estradiol (8-d P + ES) synchronization protocols for TAI. On Day -10, cows in the 7-d CO-Synch treatment group (n = 574) received a progesterone-releasing intravaginal device (PIVD; 0.5 g P4) and GnRH (0.105 mg), on Day -3 the PIVD was removed and cows received cloprostenol (0.150 mg), then, on Day 0 (64 h after PIVD removal), cows received GnRH (0.105 mg) and were TAI. On Day -10, cows in the 8-d P + ES treatment group (n = 574) received a PIVD (0.5 g P4) and estradiol benzoate (2.0 mg), on Day -2 the PIVD was removed, and cows received cloprostenol (0.150 mg) and estradiol cypionate (0.5 mg), then, on Day 0 (48 h after PIVD removal), cows were TAI. Pregnancy per TAI was determined on Days 30 and 60. In a subset of cows (7-d CO-Synch, n = 41; 8-d P + ES, n = 40), serum P4 concentration was evaluated on Day 18. In Experiment 2, anestrus (n = 34) and cyclic (n = 34) suckled beef cows were selected and submitted at random on Day -10, to either 7-d CO-Synch or 8-d P + ES treatment groups. Follicle diameter on Day -1, CL area, and serum P4 concentration on Day 7 were determined. In Experiment 1, pregnancy per TAI on Day 30 did not differ (7-d CO-Synch = 48.9%; 8-d P + ES = 45.6%) between treatments but it was greater for cows with BCS ≥5 (P < 0.01). Pregnancy loss between Days 30 and 60 did not differ between treatment groups but tended to be greater in cows with BCS <5.0 (P < 0.1). In a subset of cows, serum P4 concentration on Day 18 did not differ between treatment groups but tended to be lower (P < 0.1) in cows that had PL between Days 30 and 60 compared to cows that had no PL. In Experiment 2, FD tended to be greater (P < 0.1) and CL area was greater (P = 0.05) in anestrus cows from 7-d CO-Synch treatment. In cyclic cows, the treatment did not affect the FD or CL area. In conclusion, there was no difference in pregnancy per TAI on Day 30 and PL between Days 30 and 60 between cows using 7-d CO-Synch + PIVD or 8-d estradiol-based + PIVD protocols for estrus synchronization and TAI.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Clinical Trials, Veterinary as Topic; Cloprostenol; Dinoprost; Estradiol; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Pregnancy; Progesterone

This research aimed to determine the effect of temperament on reproductive parameters including cortisol and progesterone (P4) in Nellore cows. Additionally, two methods for increasing plasma progesterone (P4) levels in excitable animals to enhance pregnancy rate (P/AI) and reduce pregnancy loss were investigated. In total, 939 cows were subjected to timed artificial insemination (TAI) and divided into three groups: (P4LA; n = 305) 150 mg of injectable long-acting progestogen 7 days after TAI; (GnRH; n = 306), 10 μg of buserelin acetate on day 7 after TAI; control group (CG; n = 328) without hormonal treatment. In 213 cows, randomly chosen from each group, ultrasound evaluations of the preovulatory follicle (Mode B) were performed on the day of insemination and of the corpus luteum (Color Doppler) 7 and 16 days after TAI. Blood samples were obtained from 20% of the 939 animals, randomly chosen from each group, on the day of insemination and after 7 and 16 days to measure cortisol and progesterone, respectively. At the time of insemination, subjective temperament evaluations were performed with the animals being classified as excitable (EXC) or adequate (ADQ). The SAS GLIMMIX procedure was used to compare the pregnancy rate (P/AI) and gestational loss within each temperament for the three experimental groups. Continuous variables were analyzed utilizing SAS PROC MIXED procedure. Cortisol concentration was higher and POF (preovulatory follicle) and CL (corpus luteum) volumes at the time of insemination and 7 days after AI, respectively, were lower in EXC animals than in ADQ. No significant difference was observed between the number of pixels, CL intensity, and plasma concentration of P4, 7 days after TAI. However, 16 days post-insemination, among the animals classified as EXC, higher concentrations of P4 were observed in the GnRH and P4LA groups than in the control. Regarding P4 concentrations, there was a tendency to be lower in animals classified as EXC than in ADQ within the control group (P = 0.06), while rate of blood flow from the CL was lower in EXC animals than in ADQ animals (P = 0.04). Among the ADQ animals, the GnRH and P4LA groups showed a lower CL flow rate than that observed in the control (P = 0.04), 16 days after the TAI. Among EXC animals, a higher pregnancy rate was observed in the GnRH and P4LA groups than in the control group (P = 0.01). In the control group, the pregnancy rate (P/AI) of the ADQ animals was higher than that of the EXC an

Topics: Abortion, Veterinary; Animals; Buserelin; Cattle; Cattle Diseases; Dinoprost; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Hydrocortisone; Insemination, Artificial; Lactation; Pregnancy; Pregnancy Rate; Progesterone; Progestins

The objectives of the study were to determine the dose-dependent effects of active immunization against inhibin α-subunit (AIINHA) on ovarian dynamics, concentrations of progesterone (P

Topics: Abortion, Veterinary; Animals; Dinoprost; Dose-Response Relationship, Immunologic; Estrus; Female; Fertility; Goats; Gonadotropin-Releasing Hormone; Inhibins; Litter Size; Ovary; Ovulation; Pregnancy; Pregnancy Rate; Progesterone; Progestins; Seasons

The present study tested the hypothesis that administration of GnRH on day 5 of the estrous cycle in embryo transfer (ET) recipients would increase progesterone (P4) concentrations, embryo size, and improve fertility. Holstein and cross-bred Holstein heifers (n = 1562) were synchronized using a modified 5-day CIDR-Synch protocol as follows (All AM treatments): D-8, CIDR inserted; D-3, CIDR removed and PGF2α (500 μg cloprostenol) treatment; D-2, second PGF2α; D0, GnRH (G1, 100 μg gonadorelin acetate) to induce ovulation. On D5 in the afternoon, heifers were assigned in a completely randomized design to one of two treatments: Control (untreated) or GnRH (200 μg). Transfer of day 7 fresh IVP embryos was performed between D6 and D8 after G1. Data collected from each heifer included: embryo stage and quality, body condition score, technician performing ET, interval from G1 to ET, and number of previous transfers. All heifers were evaluated by transrectal ultrasonography on D5, D33, and D60 and a subset of heifers was scanned on D12 (n = 718; to determine ovulation to treatment) and another subset on D33 (n = 295; 16 s video to determine embryo and amniotic vesicle size). Serum P4 was determined from a subset of heifers on D12 (n = 467) and on D21 (n = 837) and pregnancy specific protein B (PSPB) on D28 (n = 843). Pregnancies per ET (P/ET) were analyzed by logistic regression and continuous outcomes by ANOVA. Ovulation to D5 GnRH, defined by the presence of an accessory CL on D12, was 83.9% (302/360) in GnRH-treated heifers vs. 3.3% (12/358) in Controls (P < 0.001). On D12, P4 was greater (P < 0.001) in GnRH-treated heifers (7.2 ± 0.1 ng/ml) vs Controls (6.0 ± 0.1 ng/ml). There was greater P/ET at D33 and D60 of pregnancy for Stage 7 than Stage 6 embryos. Treatment with GnRH did not alter P/ET with either embryo stage but decreased pregnancy loss between D33 and D60 in heifers receiving Stage 7 embryos. Presence of an accessory CL at the D33 pregnancy diagnosis was associated with a larger reduction in pregnancy loss from D33 to D60 in recipients of Stage 7 embryos (11.6 vs 27.6%). Although there was no GnRH effect on embryo size, the presence of an accessory CL was associated (P < 0.05) with larger amniotic vesicle volume in recipients of Stage 7 embryos. In addition, greater PSPB was linked to greater amniotic vesicle volume (P = 0.01) and to reduced pregnancy loss (P < 0.0001). In conclusion, treatment with GnRH on D5 caused ovulation and formation of an acc

Topics: Abortion, Veterinary; Animals; Blastocyst; Cattle; Dinoprost; Embryo Transfer; Female; Gonadotropin-Releasing Hormone; Ovulation; Pregnancy; Pregnancy Proteins; Progesterone

Two experiments were designed to determine the effect of expression of estrus or GnRH treatment on pregnancies per embryo transfer (P/ET) and pregnancy losses in beef recipients that were synchronized with estradiol/progesterone based protocols for fixed-time embryo transfer (FTET). Experiment 1 evaluated the effect of expression of estrus and GnRH treatment in the absence of estrus on P/ET. Beef cows (n = 729) were treated with 2 mg estradiol benzoate (EB) and an intravaginal device containing 0.5 g of progesterone. Devices were removed 8 d later and all cows received prostaglandin F2α (PGF2α), 400 IU eCG, and 0.5 mg estradiol cypionate (ECP) at that time. Expression of estrus was determined at 48 and 56 h after device removal using tail-paint and cows that did not show positive signs of estrus by 48 h received GnRH or no treatment at random. The overall estrus rate was 76.0% (554/729); 68.0% had positive signs of estrus by 48 h after progesterone device removal and 28.0% of those not in estrus by 48 h showed estrus by 56 h. The proportion of recipients receiving in vivo-derived (IVD) or in vitro-produced (IVP) embryos and P/ET were greater in recipients that showed estrus by 48 and 56 h (94.0% and 48.4%, respectively) than in those that did not show estrus 41.0% and 29.0%, respectively; P < 0.01). However, GnRH treatment of recipients not showing estrus by 48 h did not improve P/ET. Experiment 2 evaluated the effect of expression of estrus on P/ET and pregnancy loses up to parturition in recipients synchronized with two estradiol-based protocols. Beef cows (n = 403) were divided at random to receive the same synchronization protocol as in Experiment 1 (ECP) or a J-Synch protocol (device removal on day 6 and without using estradiol cypionate to induce ovulation). In this experiment, pregnancy was determined at 30 and 60 d by ultrasonography, and all pregnant recipients were followed until parturition to determine pregnancy losses during gestation. Although the number of recipients receiving IVP embryos was greater in the ECP group (90.5% vs. 83.5%; P = 0.03), P/ET did not differ (ECP: 37.0% and J-Synch: 39.0%; P = 0.43). Overall, 88.0% (357/407) of the recipients synchronized showed estrus and a greater P/ET (P = 0.05) was found in the recipients that showed estrus (39.0%) vs. those that did not show estrus (26.0%), regardless of treatment group. Pregnancy losses were lower (P = 0.004) and the calving rate was higher (P = 0.01) in recipients that showed

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Embryo Transfer; Estradiol; Estrus; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Pregnancy; Progesterone

Our objective was to evaluate the effects of temporarily decreasing progesterone (P4) after timed artificial insemination (TAI) on embryonic growth in dairy cows. Lactating Holstein cows (n = 80) were submitted to a Double-Ovsynch protocol for first TAI and were assigned randomly to receive 12.5 mg of PGF

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Leukocytes; Pregnancy; Progesterone

Our objective was to evaluate the effect of a second PGF2α treatment and duration of an Ovsynch protocol that included a progesterone-releasing intravaginal device (PRID) on progesterone (P4) concentrations and pregnancies per artificial insemination (P/AI) after resynchronization of ovulation and timed artificial insemination (TAI). Lactating Holstein cows (n=821) were assigned randomly at a nonpregnancy diagnosis (d 0) to 3 resynchronization protocols: (1) GnRH, d 0; PGF2α, d 7; GnRH, d 9.5 (7D1PGF); (2) GnRH, d 0; PGF2α, d 7; PGF2α, d 8; GnRH, d 9.5); (7D2PGF); or (3) GnRH, d 2; PGF2α, d 7; PGF2α, d 8; GnRH, d 9.5 (5D2PGF). All cows received a PRID at the first GnRH treatment of the resynchronization protocol, which was removed at the first PGF2α treatment, and all cows received TAI approximately 16h after the second GnRH treatment. Blood samples were collected from a subgroup of cows at each treatment of the resynchronization protocols. At 32 d after TAI, cows receiving a second PGF2α treatment (7D2PGF + 5D2PGF cows) had more P/AI (42.6 vs. 35.7%) than cows receiving a single PGF2α treatment (7D1PGF cows). For cows treated with a second PGF2α treatment, decreasing the duration of the protocol did not increase P/AI (41.4 vs. 43.8% for 7D2PGF vs. 5D2PGF cows). At 60 d after TAI, P/AI did not differ between cows treated with the 1 PGF2α (7D1PGF cows) or 2 PGF2α (7D2PGF + 5D1PGF cows) treatments (32.5 vs. 37.9%, respectively). In addition, reducing the duration of the protocol did not increase P/AI at 60 d after TAI (37.8 vs. 38.5% for 7D2PGF vs. 5D2PGF cows). Pregnancy loss from 32 to 60 d after TAI was not affected by the number of PGF2α treatments (8.5 vs. 10.6%, for 7D1PGF vs. 7D2PGF + 5D2PGF cows) or the duration of the protocol (9.1 vs. 12.1%, for 7D2PGF vs. 5D2PGF cows). The percentage of cows with incomplete luteal regression at the second GnRH treatment tended to differ among treatments and was lowest for 7D2PGF cows, intermediate for 5D2PGF cows, and greatest for 7D1PGF cows (1.9 vs. 6.9 vs. 11.0%, respectively). In conclusion, addition of a second PGF2α treatment tended to decrease the percentage of cows with incomplete luteal regression and increased P/AI 32 d after AI, whereas decreasing the duration of the Ovsynch protocol did not increase P/AI.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovulation; Progesterone

Fertility to timed AI (TAI) is profoundly affected by progesterone (P4) levels during hormonal synchronization protocols. Holstein-Friesian dairy cows managed in a seasonal-calving, pasture-based production system were randomly assigned to 2 treatments to manipulate P4 before TAI during growth of the preovulatory follicle. Cows in the first treatment (High P4; n=30) were submitted to a Double-Ovsynch protocol {Pre-Ovsynch [GnRH; 7 d, PGF2α; 3 d, GnRH] followed 7 d later by Breeding-Ovsynch [GnRH (G1); 7 d PGF2α; 24 h, PGF2α; 32 h, GnRH (G2); 16 h, TAI]}. Cows in the second treatment (n=30; Low P4) received the same Double-Ovsynch protocol but with an additional PGF2α treatment 24 h after G1. Overall, synchronization rate did not differ between treatments and was 92% (55/60). Unexpectedly, 37% of Low P4 cows were detected in estrus ~24 h before scheduled TAI and were inseminated ~16 h before scheduled TAI. Overall, P4 did not differ between treatments at G1, whereas High P4 cows had greater P4 concentrations at PGF2α and G2 than Low P4 cows. High P4 cows had the smallest mean follicle diameter at G2, whereas Low P4 cows with no estrus before TAI had intermediate mean follicle diameter at G2, and Low P4 cows with estrus before TAI had the largest mean follicle diameter. Low P4 cows with estrus before TAI had larger corpora lutea 15 d after TAI than Low P4 cows without estrus before TAI or High P4 cows. In accordance with corpus luteum size on d 15, High P4 cows and Low P4 cows without estrus before TAI had lower P4 from 4 to 46 d after TAI than Low P4 cows with estrus before TAI. Relative mRNA levels of the interferon-stimulated genes ISG15, MX1, MX2, and OAS1 were greater for Low P4 than for High P4 cows, whereas relative mRNA levels of RTP4 were greater for High P4 than for Low P4 cows 18 d after TAI. Treatment did not affect plasma pregnancy-associated glycoprotein concentrations after TAI; however, pregnancy-associated glycoprotein concentrations were affected by pregnancy status and parity. Treatment did not affect pregnancy per artificial insemination at 29, 39, or 60 d after TAI, and no pregnancy losses were observed from 39 to 60 d after TAI. We concluded that (1) Low P4 cows were more likely to express estrus than High P4 cows; (2) the subpopulation of Low P4 cows that expressed estrus had larger preovulatory follicles and greater P4 concentrations after TAI; and (3) regardless of estrus before TAI, all Low P4 cows had greater mRNA expression for 5

Topics: Abortion, Veterinary; Animals; Breeding; Cattle; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Progesterone; Seasons

Pregnancy failure during placentation in lactating dairy cows was associated with low concentrations of serum progesterone. Beef cows have greater serum progesterone and less pregnancy failure. Experiment 1 determined that reduction of serum progesterone affected late embryonic/early fetal loss in suckled beef cows. Cows (n=40) received progesterone from two new or used controlled internal drug releasing devices, replaced every 5d, beginning on Day 28 of gestation (mating=Day 0); CL were enucleated on Day 29. Retention of pregnancy was 77% in treated cows and 97% in 78 control cows (P<0.05). Experiment 2 determined how pregnant, lactating dairy cows with high or low progesterone concentrations during Days 28-34 differed in luteal function or in serum progesterone during replacement therapy. Luteal tissue from such cows was assayed for progesterone and expression of mRNA for genes of endothelin and prostaglandin (PG) systems. Secretion of progesterone and prostaglandins by dispersed luteal cells was determined during incubation with LH, endothelin-1, or arachidonic acid. Neither luteal progesterone nor mRNAs for endothelin or prostaglandin systems differed. Endothelin-1 inhibited secretion of progesterone more (P<0.05) in luteal cells from cows with low versus high serum progesterone, when incubated with arachidonic acid. Secretion of prostaglandin F(2)alpha was increased and that of 6-keto-PGF(1)alpha decreased by endothelin-1 in vitro. Serum progesterone during replacement was lower (P<0.05) for cows with low than high serum progesterone at lutectomy. Thus, clearance, more than luteal production, determined peripheral progesterone in pregnant, lactating dairy cows.

Topics: 6-Ketoprostaglandin F1 alpha; Abortion, Veterinary; Animals; Cattle; Cells, Cultured; Corpus Luteum; Dinoprost; Female; Lactation; Pregnancy; Progesterone; Risk Factors

The objectives were to evaluate factors affecting reproductive performance of dairy heifers. Holstein heifers (6389) were housed in a feed lot located in Parma, ID. Each week heifers weighing > or =290 kg were initiated in the reproductive program, which consisted of one injection of PGF(2alpha) and AI on detection of estrus. Heifers not inseminated by 11 days after the initiation of the breeding program received a second injection of PGF(2alpha). Pregnancy was diagnosed at 40+/-3 and 90+/-3 days after AI. Average daily minimum temperature (ADMnT), average daily maximum temperature (ADMxT), and average daily rainfall (ARF) were recorded between 15 days prior to and 15 days after the day of AI or the day of initiation of the breeding program. Exposure to air temperature was classified as: cold stress (CS=ADMnT< or =4 degrees C), no stress (NS=ADMnT>4 degrees C and ADMxT<29 degrees C), and heat stress (HS=ADMxT> or =29 degrees C). Exposure to rainfall was classified as above (HRF) or below (LRF) the mean for the period in question. Heifers were classified according to body weight at initiation of the breeding program as thin (TH<340 kg); moderate (MD=340-365 kg); and heavy (HY>365 kg). Service sire was associated with conception rate at 40 and 90 days after first AI. Although exposure to air temperature was not correlated with conception rate at 40 days after first AI, heifers exposed to cold stress had smaller conception rates at 90 days after first AI because they were more likely to lose pregnancy between 40 and 90 days of gestation. The proportion of heifers inseminated after initiation of the breeding program was correlated with body weight and exposure to cold stress. Exposure to cold stress was also correlated with the proportion of heifers conceiving within 11 and 22 days after initiation of the breeding program. From this study a correlation was established between body weight and rate of insemination and between the exposure to cold stress and reproductive efficiency of Holstein heifers.

Topics: Abortion, Veterinary; Aging; Animal Husbandry; Animals; Body Weight; Cattle; Dinoprost; Environment; Estrous Cycle; Female; Insemination, Artificial; Light; Odds Ratio; Oxytocics; Pregnancy; Reproduction

To assess the efficacy and safety of 2 protocols using bromocriptine mesylate and prostaglandins to terminate unwanted pregnancy in bitches.. Prospective randomized single-blind controlled study.. 34 crossbred and purebred bitches referred for possible pregnancy termination. Seven additional pregnant bitches were used as controls.. Pregnancy was assessed by ultrasonographic examination from day 25 after mating in all bitches. Of the 34 bitches, 25 were pregnant and were randomly allocated to a treatment group. Group-1 dogs (n = 12) received a combination of increasing amounts of bromocriptine mesylate (15 to 30 microg/kg [6.8 to 13.6 microg/lb], p.o., q 12 h) and dinoprost tromethamine (0.1 to 0.2 mg/kg [0.045 to 0.09 mg/lb], s.c., q 24 h). Group-2 dogs (n =13) received a combination of increasing amounts of bromocriptine mesylate (the same schedule as group-1 dogs) and cloprostenol sodium (1 microg/kg [0.45 microg/lb], s.c., q 48 h). Both groups were treated until pregnancy termination. Results-Treatment success was 100% in both groups. Days of treatment required for pregnancy termination did not significantly differ between groups (5.0 +/- 0.6 vs 3.7 +/- 0.6 days, group-1 and group-2 dogs, respectively) although adverse effects only developed in group-1 dogs. At the end of the protocols, pseudopregnancy was observed in 3 of 12 and 6 of 13 group-1 and group-2 dogs, respectively. Pregnancy termination was followed by a mucoid sanguineous vulvar discharge for 3 to 10 days.. Results of this study indicate that protocols that combine the use of bromocriptine mesylate and prostaglandins for the termination of unwanted pregnancy in bitches are efficient and safe. The use of bromocriptine mesylate and cloprostenol had the best results and could be easily used on an outpatient basis.

Topics: Abortifacient Agents, Nonsteroidal; Abortion, Induced; Abortion, Veterinary; Animals; Bromocriptine; Cloprostenol; Dinoprost; Dogs; Female; Pregnancy; Prospective Studies; Prostaglandins; Safety; Single-Blind Method; Treatment Outcome

Administration of progesterone in poly(d-,l-lactide) microspheres was used to maintain pregnancy in mares after luteolysis was induced by treatment with prostaglandin F2 alpha at day 14 of pregnancy. Mares were given vehicle only (control, n = 6) or 0.75 g (n = 7), 1.5 g (n = 8), or 2.25 g (n = 5) of microencapsulated progesterone at days 12 and 22 of pregnancy. Serum progesterone concentrations were determined daily, and pregnancy was evaluated by transrectal ultrasonography on alternate days. Significantly (P less than 0.05) more mares given 1.5 or 2.25 g of progesterone (6 of 8 and 4 of 5 mares, respectively), but not those given 0.75 g (3 of 7 mares), maintained pregnancy through day 32, compared with control mares (0 of 6). Progesterone concentrations decreased significantly (P less than 0.025) in all groups after administration of prostaglandin F2 alpha at day 14, and significant (P less than 0.05) effects of time and treatment on progesterone concentrations were found between days 12 and 22, and 22 and 32. Although treatment with 1.5-g and 2.25-g doses of microencapsulated progesterone improved maintenance of pregnancy, compared with that of vehicle-treated controls, administration of 2.25 g of microencapsulated progesterone appeared to be most efficacious in maintenance of pregnancy during the study interval.

Topics: Abortion, Veterinary; Animals; Corpus Luteum; Dinoprost; Female; Horse Diseases; Horses; Microspheres; Pregnancy; Progesterone; Ultrasonography, Prenatal

The objective of this study was to compare the reproductive outcomes (artificial insemination [AI] pregnancy rates, season pregnancy rates, AI pregnancy losses) and calf traits (birth and weaning weights) after vaccination of suckled beef cows against bovine herpesvirus 1 and bovine viral diarrhea virus using commercially-available modified-live virus (MLV) or killed virus (KV) vaccine at the initiation of a fixed-time AI program. Previously-vaccinated cows (n = 2138) on 14 farms throughout Virginia were enrolled in the study during the Fall 2017 and Spring 2018 breeding seasons. Animals received a single vaccination injection at 10 d pre-breeding, corresponding with time of CIDR insertion at initiation of the 7-d CO-Synch + CIDR synchronization protocol. Cows were inseminated at a fixed time (60-66 h after removal of the CIDR insert) and subsequently turned out with bulls approximately 1 wk after insemination for a natural service. Cows treated with the MLV vaccine had greater AI pregnancy rates than cows treated with the KV vaccine during the fall (P = 0.008; 54% vs. 46%, respectively), but not during the spring breeding season (P = 0.62; 48 vs. 49%). Season pregnancy rates were greater (P = 0.01) in the fall (95-96%) than in the spring breeding season (89-90%), but were not affected by vaccine treatment (P = 0.49) or treatment by season (P = 0.30) interactions. Percentage of AI pregnancy losses was not affected by season (P = 0.85), vaccine treatment (P = 0.83), or treatment by season interactions (P = 0.68). The number of cycles it took for cows to become pregnant by natural service differed by season (P = 0.006) but not treatment (P = 0.87) or treatment by season interaction (P = 0.997). Cows treated with the MLV vaccine gave birth earlier in the calving season (8.36 ± 0.6 d) than those treated with the KV vaccine (10.31 ± 0.6 d; P = 0.02). There was a main effect of season on birth weights (P = 0.008), weaning weights (P < 0.001), and ADG at weaning (P < 0.001), but no effects of treatment (P ≥ 0.26) or treatment by season interaction (P ≥ 0.10) on any of these parameters. Overall, this study demonstrated that the administration of an MLV vaccine at 10 d before fixed-time AI did not have any adverse effects on pregnancy or calf outcomes compared with KV vaccine administration.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Male; Pregnancy; Pregnancy Outcome; Pregnancy Rate; Progesterone; Vaccination; Vaccines

The objectives of this study were to investigate whether estrous activity and its impact on pregnancy outcomes would differ in heifers subjected to a 5 d CO-Synch plus progesterone releasing intravaginal device (PRID) protocol with or without an initial GnRH treatment. Holstein Heifers (n = 308) were fitted with a collar-mounted automated activity monitoring system approximately 1 week prior to the initiation of the synchronization protocol (Day -7). Heifers were assigned randomly to a 5 d CO-Synch plus PRID protocol either with (GnRH; n = 154) or without (NGnRH; n = 154) an initial administration of 100 μg of GnRH at the time of PRID insertion (Day 0). Heifers received a single administration of 500 μg of cloprostenol (PGF) at the time of PRID removal (Day 5) and again 24 h later (Day 6). Approximately 72 h after PRID removal (Day 8), heifers were timed-inseminated (TAI) and concurrently 100 μg of GnRH was administered to those not exhibiting estrus. All inseminations were done by one of two technicians using either sex-sorted (n = 252) or conventional (n = 56) frozen-thawed semen. Transrectal ultrasonography was done on Day 0 to determine ovarian cyclicity and normalcy of the reproductive tract and 30 and 45 d post-TAI to determine and confirm pregnancy, respectively. The percentage of heifers determined to be in estrus following PRID removal was greater in the GnRH than in the NGnRH group (94 vs. 82%, respectively; P < 0.01). The mean interval from PRID removal to the onset of estrus was shorter for GnRH- than NGnRH-treated heifers (50.8 vs. 59.2 h, respectively; P < 0.01). Pregnancy per AI (P/AI) at 30 d post-TAI tended to be greater for GnRH than NGnRH heifers (68 vs. 59%, respectively; P = 0.1). However, P/AI at 45 d post-TAI (65 vs. 57%, respectively) and pregnancy loss between 30 and 45 d post-TAI (6 vs. 4.5%, respectively) did not differ. The association between the interval from PRID removal to the onset of estrus and P/AI at 30 d post-TAI was linearly negative for GnRH heifers; for every 1 h increase in the interval from PRID removal to the onset of estrus, the predicted probability of P/AI at 30 d post-TAI tended (P = 0.08) to be reduced by 2.7%. The association between the interval from PRID removal to the onset of estrus and P/AI at 30 d post-TAI was not significant for NGnRH heifers. In addition, the interval from TAI to subsequent estrus, in non-pregnant heifers, was approximately 3 d longer for the GnRH than the NGnRH group (20.7 vs. 17.5

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Estrus; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Pregnancy; Pregnancy Outcome; Progesterone

The objectives of this study were to investigate the effect of presynchronization or dose of GnRH on ovulatory response to initial GnRH, estrus expression and reproductive outcomes in Holstein heifers subjected to a progesterone based 5-d CO-Synch protocol. Heifers were fitted with a collar-mounted automated activity monitoring system on Day -5 and were assigned randomly to one of three groups: 1) G100 (n = 111), a 5-d CO-Synch plus PRID protocol with administration of 100 μg of GnRH at the time of PRID insertion (Day 0), 500 μg of cloprostenol (PGF) at the time of PRID removal (Day 5) and again 24 h later (Day 6); 2) G200 (n = 112), same as G100 except 200 μg GnRH was administered on Day 0; 3) P10 (n = 111), PRID + PGF on Day -5 followed by a 5 d CO-Synch with administration of 100 μg of GnRH on Day 0, PGF at the time of PRID removal (Day 5) and again 24 h later (Day 6). Approximately 72 h after PRID removal (Day 8), all heifers were timed-inseminated (TAI) and concurrently 100 μg of GnRH was administered to those not exhibiting estrus. All inseminations were done by one technician using either sex-sorted (n = 265) or conventional (n = 69) frozen-thawed semen. Transrectal ultrasonography was done to determine ovarian cyclicity and normalcy of the reproductive tract, ovarian dynamics and pregnancy. All heifers were cyclic and ovulatory response to initial GnRH was greater (P < 0.01) in G200 (51.8%) and P10 (47.7%) compared to G100 (27.9%). Estrus expression rate tended to be greater (P = 0.08) in G100 (93.7%) compared to G200 (85.7%) and intermediate in P10 (89.2%). Expression of estrus was associated positively with P/AI at 45 d post-TAI (P < 0.01; 70.2 vs. 31.4% for heifers expressing or not expressing estrus). Heifers in the G200 group had greater P/AI at 30 (P < 0.01) and 45 (P = 0.01) d post-TAI (79.5 and 75.9%, respectively) compared to those in G100 (63.1 and 60.4%) or P10 (64.0 and 62.2%) groups. Pregnancy loss did not differ among treatment groups (overall 3.9%). Results indicate that increasing the dose of the initial GnRH from 100 to 200 μg resulted in increased ovulatory response and improved P/AI in Holstein heifers subjected to a progesterone based 5-d CO-Synch protocol. Although heifers presynchronized with a combination of PRID and PGF had an increased ovulatory response to the initial GnRH, P/AI did not differ from the standard progesterone based 5-d CO-Synch protocol.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Pregnancy; Progesterone

The hypothesis of this study tested whether application of designed treatments to synchronize estrus in nonpregnant previously inseminated lactating dairy cows increased the proportion of nonpregnant cows in estrus before early pregnancy diagnosis on Day 32 after the previous insemination (Day 0) and increase fertility of the pretreatment insemination. A progesterone insert (CIDR) and GnRH were applied to cows after insemination to resynchronize the returning estrus of cows that failed to conceive on Day 0. The combination of GnRH (Day 14) and a CIDR insert (d 17 through 24) in experiment 1 (n = 347 cows) did not increase (P = 0.13) the proportion of nonpregnant cows returning to estrus before pregnancy diagnosis, but increased (P < 0.01) the synchrony of their return by 24.4% points, and delayed (P < 0.01) that return by 2.3 ± 0.3 d compared with controls. Ovulation risk after GnRH treatment on Day 14 was only 10%. For cows that failed to return to estrus before Day 32, progesterone concentration on Days 14 and 17 were less than that in cows that returned to estrus by Day 32 and in pregnant cows. Cows that returned to estrus had larger follicles and fewer numbers of CL on Day 21 than pregnant cows and cows that failed to return to estrus, but concentrations of pregnancy-associated glycoproteins on Day 28 indicated that cows failing to return to estrus were likely pregnant but suffered embryo death. In experiment 2 (n = 881), use of GnRH alone (Day 7), a CIDR insert alone (Days 14 through 21), or in combination, failed to increase the proportion of nonpregnant cows in estrus before pregnancy diagnosis on Day 32 compared with controls. Cows receiving the CIDR insert had increased (P < 0.01) synchrony of estrus by 24-34% points compared with cows that did not receive a CIDR insert. More cows receiving GnRH had 2 or more CL on Days 14 and 21 compared with controls. Ovulation risk after GnRH on Day 7 was greater than 66%. In both experiments combined, treatments with GnRH or GnRH + CIDR insert increased (P = 0.015) pretreatment pregnancy per AI by 7.1% points, but did not affect pregnancy loss. Although administering GnRH with or without a CIDR insert synchronized returns to estrus, treatments failed to increase the proportion of nonpregnant cows reinseminated before pregnancy diagnosis, but increased pretreatment pregnancy risk.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Estrus; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Pregnancy; Progesterone

The objective of this experiment was to determine whether uterine or ovarian vascular dynamics could be used to identify cows at risk for pregnancy loss. Our hypothesis was that cows that subsequently lose their pregnancy will have decreased corpus luteal (CL) perfusion, or an increased resistance index (RI; reduced blood flow), or both, at d 34 of pregnancy. Day 34 was chosen because it is a common time for dairy cattle to be checked for pregnancy. This experiment was performed in 2 replicates from November 2011 to April 2012 (n = 69) and from November 2012 to April 2013 (n = 53). Cows were bred via timed artificial insemination using Ovsynch-56 and checked for pregnancy on d 32 after artificial insemination. At d 34, cows confirmed pregnant were examined via transrectal Doppler ultrasonography. Blood samples collected via coccygeal vein were used to measure circulating plasma progesterone concentrations. Diameter of the corpus luteum and crown-rump length were measured. Color power Doppler ultrasonography was used to determine vascular perfusion to the CL, and RI was measured for the uterine arteries just after branching from the umbilical artery. Records were later examined to identify pregnancy status of cows after reconfirmation. Abortion rate did not differ between replicates (11.6% in replicate 1, 9.4% in replicate 2). Mean crown-rump length of embryos that were carried to term was greater on d 34 than that in cows that aborted (14.23 ± 0.27 vs. 13.21 ± 0.53 mm). Circulating progesterone concentration at d 34 was greater for cows that carried pregnancies to term than for those that aborted (9.1 ± 0.7 vs. 7.5 ± 1.0 ng/mL). The final logistic regression model consisted of crown-rump length, progesterone concentration, and RI of the uterine artery contralateral to pregnancy. Decreased crown-rump length and progesterone concentration tended to be associated with increased odds ratio for pregnancy loss, whereas CL perfusion and uterine blood flow were not associated with increased odds ratio of pregnancy loss. In conclusion, examining CL perfusion and RI of the uterine arteries on d 34 of pregnancy does not offer a method to identify lactating Dairy cattle at risk for pregnancy loss after d 34.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Pregnancy; Progesterone; Ultrasonography, Doppler

The objective of this study was to determine whether induced luteolysis of one of the two corpora lutea in twin pregnancies would provoke spontaneous twin reduction. In Experiment 1, 12 post-partum cows with two corpora lutea in the same ovary were assigned to (three cows per group): Group I, Group II, Group III or Group IV receiving into one of the corpora lutea puncture with no treatment, 0.5 mg dinoprost, 1.5 mg dinoprost and 2.5 mg dinoprost, respectively. One of the two corpora lutea showed clear signs of luteolysis on Day 2 and was practically non-detectable on Day 7 after treatment in the three cows of the Group IV. In Experiment 2, 11 cows carrying live twins with two corpora lutea on Day 28 of gestation, eight bilateral and three unilateral, received 2.5 mg dinoprost into one of the corpora lutea. Corpus luteum reduction and embryo reduction after treatment were registered in 10 and 9 cows, respectively. In bilateral twin pregnancies, four cows suffering embryo reduction remained pregnant. In unilateral twin pregnancies, membrane detachment resulted in the death of both cotwins. In conclusion, although observations were based on few animals, there seems to be a mechanism that operates locally to transfer ovarian progesterone to the uterus, and also a quantitative relationship between the amount of progesterone secreted and support of conceptuses, resulting in death of one twin embryonic vesicle when one corpus luteum regresses.

Topics: Abortion, Veterinary; Animals; Corpus Luteum; Dinoprost; Female; Ovarian Follicle; Ovulation; Pregnancy; Pregnancy, Animal; Pregnancy, Multiple

The objectives of this study were to determine the effects of supplemental progesterone on fertility responses of lactating dairy cows with a CL at the initiation of the timed artificial insemination (AI) program. Holstein cows were subjected to the Ovsynch protocol (Day -10 GnRH, Day -3 PGF2α, Day -0.7 GnRH, and Day 0 timed AI). Ovaries were scanned by ultrasonography on Day -10 and cows with CL were blocked by pen and assigned randomly to receive no supplemental progesterone (control, n = 863) or to receive a controlled internal drug-release (CIDR) insert containing progesterone from Days -10 to -3 (1CIDR, n = 862). Cows were observed for signs of estrus beginning on Day -9 based on removal of tail chalk and those in estrus received AI on the same day. Blood sampled from a subset of cows was analyzed for progesterone concentrations on Days -10, -9, -7, -5, -3, 0, 6, 13, and 19. Pregnancy was diagnosed on Days 32 and 60 after AI. Supplementation increased (P < 0.01) progesterone concentrations between Day -9 and -3 compared with control (7.5 vs. 6.2 ng/mL). Treatment had no effect on the ovulatory response to the first and final GnRH injections of the Ovsynch protocol, the proportion of cows that maintained their CL until the day of PGF2α injection, or the diameter of the ovulatory follicle before AI. Although the overall proportion of cows in estrus at AI did not differ between treatments, progesterone supplementation prevented (P < 0.01) cows from coming into estrus from Days -9 to -3 (0.0% vs. 4.7%), whereas it increased (P = 0.02) the proportion of cows inseminated in estrus from Days -2 to -1 (7.1% vs. 4.5%). Pregnancy per AI (P/AI) tended to be reduced (P = 0.06) by supplemental progesterone on Day 32 (40.5% vs. 45.0%), but not on Day 60 after AI (36.6% vs. 39.7%). A tendency for an interaction (P = 0.09) between treatment and the presence of CL at the PGF2α injection was observed for P/AI on Day 32 in cows that received timed AI because progesterone supplementation reduced P/AI in cows that maintained their CL until Day -3 (40.3% vs. 46.7%); however, it increased P/AI in those that did not have a CL at PGF2α (38.1% vs. 27.7%). Treatment did not affect pregnancy loss between Days 32 and 60 of gestation. In conclusion, incorporating a single intravaginal insert to the timed AI program increased progesterone concentrations in plasma by 1.3 ng/mL, but did not benefit fertility in dairy cows that have CL at the initiation of the synchronization protoco

Topics: Abortion, Veterinary; Administration, Intravaginal; Animals; Cattle; Cattle Diseases; Corpus Luteum; Dinoprost; Estrus; Estrus Synchronization; Female; Fertility; Gestational Age; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovarian Follicle; Ovary; Ovulation Induction; Pregnancy; Progesterone; Ultrasonography

Ovulation to the first GnRH (G1) treatment of the Ovsynch protocol improves synchronization rate and pregnancies per AI (P/AI). Elevated progesterone (P4) concentrations at G1 decrease the ovulatory response by decreasing the magnitude of the GnRH-induced LH surge. Therefore, our objective was to evaluate the effect of temporarily decreasing P4 concentrations before initiation of an Ovsynch protocol on ovulatory response to G1 and P/AI. Lactating Holstein cows (n=800) at 53±3 (herd A) or 51±3 (herd B) d in milk (DIM) were synchronized using a modified Double-Ovsynch protocol [pre-Ovsynch protocol (d 0, GnRH; d 7, PGF2α; d 10, GnRH) followed 7 d later by an Ovsynch-56 protocol (d 0, G1; d 7, PGF2α; d 8, PGF2α; d 9.5, GnRH)] to receive first timed artificial insemination (TAI; 80±3 DIM) 16h after the last GnRH treatment. Cows were randomly assigned to receive 12.5mg of PGF2α (a half-dose of dinoprost tromethamine) 2 d before G1 (low-P4) or serve as untreated controls (high-P4). Overall, high-P4 cows had greater P4 concentrations at G1 compared with low-P4 cows (3.0 vs. 1.3ng/mL, respectively). Ovulatory response to G1 was greater for low-P4 than high-P4 cows [81.1 vs. 60.3%, respectively]. Premature luteal regression during the second Ovsynch protocol did not differ between treatments [15.0% vs. 10.7%; for low-P4 vs. high-P4 cows, respectively]. Overall, P/AI did not differ between treatments 32 d after TAI [56.3 vs. 52.9%, for low-P4 vs. high-P4 cows, respectively] or 67 d after AI [50.5 vs. 47.6%, for low-P4 vs. high-P4 cows, respectively]. Pregnancy loss from 32 to 67 d after TAI did not differ between treatments [9.9 vs. 9.3%, for low-P4 vs. high-P4 cows, respectively]. Overall, cows that ovulated to G1 had more P/AI than cows that did not ovulate [58.2 vs. 41.8%, respectively]. The increase in P/AI for cows that ovulated to G1 (16.4%) combined with the observed increase in ovulation to G1 due to treatment (20.8%; low-P4 - high-P4) resulted in the expected numerical increase in P/AI of 3.4% in low-P4 versus high-P4 cows observed in this experiment. We conclude that administration of a half-dose of PGF2α 2 d before G1 during a Double-Ovsynch protocol decreased P4 at G1 and increased ovulatory response to G1.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Luteolysis; Milk; Ovulation; Ovulation Induction; Pregnancy; Progesterone

The objective was to examine the relationship between ovulatory follicle size and embryo and fetal survival by using circulating concentrations of bovine pregnancy associated glycoproteins (bPAG) to detect the presence of an embryo or fetus and monitor placental function. Before examining the relationship between bPAG, ovulatory follicle size, and embryo and fetal survival, the half-life of bPAG was determined in Exp. 1. The half-life of bPAG after PGF2α-induced abortion on d 32 to 36 postinsemination was 35.8 ± 21.9 h (mean ± SD; range 7.1 to 78.5 h). In Exp. 2, suckled beef cows (n = 91) were treated with the CO-Synch protocol (GnRH on d -9, PGF2α on d -2, and GnRH and AI 48 h later [d 0]) and classified into 1 of 2 ovulatory follicle size groups: 1) small follicle (<12.5 mm; n = 25) or 2) large follicle (≥ 12.5 mm; n = 66). The first increase (P < 0.0001) in serum bPAG occurred in pregnant cows on d 24 after insemination and circulating bPAG decreased before a decrease in progesterone in 3 of 4 cows that lost an embryo or fetus. Pattern of secretion of bPAG in serum from d 24 to 60 after insemination (d 0) was affected by day (P < 0.0001), but not ovulatory follicle size. In Exp. 3, suckled beef cows (n = 1164) were administered the CO-Synch protocol either with (donor cows; n = 810) or without (recipient cows; n = 354) AI on d 0. Single embryos (n = 394) or oocytes (n = 45) were recovered from the donor cows [d 7; embryo transfer (ET)] and all live embryos were transferred into recipients the same day. Cows were classified on d 0 as having a small (<12.5 mm) or large (≥ 12.5 mm) ovulatory follicle, and randomly chosen as donors or recipients to remove confounding effects of ovulatory follicle size on fertility. Serum concentration of bPAG at d 28 was not affected by ovulatory follicle size (P = 0.85), embryo stage at ET (P = 0.75), embryo quality at ET (P = 0.64), estradiol at GnRH2 (P = 0.62) or serum progesterone at ET (d7; P = 0.14). Compared with cows that maintained pregnancy (n = 176), cows that exhibited late embryonic or fetal mortality (n = 19) after d 28 had decreased (P < 0.05) concentrations of bPAG on d 28. In summary, there was no relationship between serum bPAG and ovulatory follicle size or embryo stage or quality at ET; however, cows that lost an embryo after d 28 had reduced concentrations of bPAG on d 28 compared with cows that maintained pregnancy.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Embryo Transfer; Estradiol; Female; Fertility; Gonadotropin-Releasing Hormone; Half-Life; Ovarian Follicle; Ovulation; Pregnancy; Pregnancy-Specific beta 1-Glycoproteins; Progesterone; Random Allocation

The objective was to determine the effect of exogenous progesterone (P4) in a timed artificial insemination (TAI) protocol initiated at 2 different times post-AI on pregnancies per AI (P/AI) in lactating dairy cows. Cows (n=1,982) in 5 dairy herds were assigned randomly at a nonpregnancy diagnosis 32 ± 3 d post-AI to 1 of 4 resynchronization (RES) treatments arranged in a 2 × 2 factorial design using the Ovsynch-56 (GnRH, 7d later PGF2α, 56 h later GnRH, 16 h later TAI) protocol. Treatments were as follows: cows initiating RES 32 ± 3 d after AI with no supplemental P4 (d 32 RES-CON; n=516); same as d 32 RES-CON plus a controlled internal drug release (CIDR) insert containing P4 at the onset of Ovsynch-56 (d 32 RES-CIDR; n=503); cows initiating RES 39 ± 3 d after AI (d 39 RES-CON; n=494); and same as d 39 RES-CON plus a CIDR (d 39 RES-CIDR; n=491). Cows were inseminated if observed in estrus before TAI. The P/AI was determined 32 and 60 d after TAI. In a subgroup of cows (n=1,152), blood samples were collected and ovarian structures examined by ultrasonography on the days of the first GnRH (G1) and PGF2α of Ovsynch-56. Percentage of cows with a corpus luteum (CL) at G1 was unaffected by timing of treatments, but percentage of cows with a CL at PGF2α was greater for d 32 than for d 39 cows (87.9 vs. 79.4%). In addition, percentage of cows with P4 ≥ 1 ng/mL at G1 was unaffected by timing of treatments, but was increased for d 32 compared with d 39 RES cows on the day of the PGF2α of the RES protocols (86.5 vs. 74.3%). Treatment did not affect ovulation to G1 or P/AI 32 d after RES TAI (d 32 RES-CON=30.1%, d 32 RES-CIDR=28.8%, d 39 RES-CON=27.5%, d 39 RES-CIDR=30.5%). A greater percentage of d 39 RES cows underwent premature luteolysis during the RES protocol compared with d 32 RES cows. An interaction was detected between day of RES initiation and CIDR treatment, in which the CIDR increased P/AI 60 d after TAI for d 39 (CON=23.7% vs. CIDR=28.0%), but not for d 32 (CON=26.9% and CIDR=24.2%) cows. Pregnancy loss was unaffected by treatment. In addition, cows had improved P/AI 60 d after TAI when they received a CIDR and did not have a CL (CON-CL=28.2%, CON-No CL=19.2%, CIDR-CL=27.0%, and CIDR-No CL=26.5%) or had P4 <1 ng/mL (CON-High P4=27.8%, CON-Low P4=15.0%, CIDR-High P4=25.0%, and CIDR-Low P4=29.4%) at G1, but not if a CL was present or P4 was ≥ 1 ng/mL at G1. In conclusion, addition of a CIDR insert to supplement P4 during the RES protocol increased P/AI

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus; Estrus Detection; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovary; Ovulation Induction; Pregnancy; Pregnancy Outcome; Progesterone; Time Factors; Ultrasonography

The objective of this study was to compare a GnRH-based to an estrogen/progesterone (E2/P4)-based protocol for estrous cycle synchronization and fixed timed artificial insemination (TAI), both designed for synchronization of ovulation and to reduce the period from follicular emergence until ovulation in cows with a synchronized follicular wave. A total of 1,190 lactating Holstein cows (primiparous: n=685 and multiparous: n=505) yielding 26.5 ± 0.30 kg of milk/d at 177 ± 5.02 d in milk were randomly assigned to receive one of the following programs: 5-d Cosynch protocol [d -8: controlled internal drug release (CIDR) + GnRH; d -3: CIDR removal + PGF2α; d -2: PGF2α; d 0: TAI + GnRH] or E2/P4 protocol (d -10: CIDR + estradiol benzoate; d -3: PGF2α; d -2: CIDR removal + estradiol cypionate; d 0: TAI). Rectal temperature and circulating progesterone (P4) were measured on d -3, -2, 0 (TAI), and 7. The estrous cycle was considered to be synchronized when P4 was ≥ 1.0 ng/mL on d 7 in cows that had luteolysis (P4 ≤ 0.4 ng/mL on d 0). To evaluate the effects of heat stress, cows were classified by number of heat stress events: 0, 1, and 2-or-more measurements of elevated body temperature (≥ 39.1 °C). Pregnancy success (pregnancy per artificial insemination, P/AI) was determined at d 32 and 60 after TAI. The cows in the 5-d Cosynch protocol had increased circulating P4 at the time of PGF2α injection (2.66 ± 0.13 vs. 1.66 ± 0.13 ng/mL). The cows in the E2/P4 protocol were more likely to be detected in estrus (62.8 vs. 43.4%) compared with the cows in the 5-d Cosynch protocol, and expression of estrus improved P/AI in both treatments. The cows in the 5-d Cosynch protocol had greater percentage of synchronized estrous cycle (78.2%), compared with cows in the E2/P4 protocol (70.7%). On d 60, the E2/P4 protocol tended to improve P/AI (20.7 vs. 16.7%) and reduced pregnancy loss from 32 to 60 d (11.0 vs. 19.6%), compared with the 5-d Cosynch protocol. In cows withtheir estrous cycle synchronized, the E2/P4 protocol had greater P/AI (25.6 vs. 17.7%) on d 60 and lower pregnancy loss from 32 to 60 d (6.7 vs. 21.7%) compared with cows in the 5-d Cosynch protocol. Follicle diameter affected pregnancy loss from 32 to 60d only in the cows in the 5-d Cosynch protocol, with smaller follicles resulting in greater pregnancy loss. Pregnancy per AI at d 60 was different between protocols in the cows with 2 or more measurements of heat stress (5-d Cosynch=12.2% vs. E2/P4=22.8%), but not

Topics: Abortion, Veterinary; Animals; Body Temperature; Cattle; Contraceptive Agents; Dinoprost; Estradiol; Estrogens; Estrous Cycle; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovarian Follicle; Ovulation; Oxytocics; Pregnancy; Progesterone

A protocol for presynchronization of ovarian status with 2 injections of PGF2α given 14 d apart, with the last PGF2α injection given 12 or 14 d before Ovsynch increases pregnancy per artificial insemination (P/AI) in dairy cows. We determined the efficacy of reducing the interval from the last PGF2α injection (500 μg of cloprostenol) of presynchronization to initiation of Ovsynch on response to treatment and P/AI. Lactating dairy cows were assigned to an Ovsynch protocol, with the initial injection of GnRH given either 9 (PRE-9; n=135) or 12d (PRE-12; n=135) after the second PGF2α injection of presynchronization. The Ovsynch protocol consisted of 2 injections of 100 μg of GnRH given 9 d apart and 1 injection of PGF2α given 7 d after the initial GnRH injection, and cows were subjected to timed artificial insemination (TAI; 70±3.5 DIM) approximately 16 h after the second GnRH injection. Body condition score (1-5 scale) was recorded at TAI. Blood samples were taken for progesterone determination at the PGF2α injection of Ovsynch, at TAI, and at 11 d after TAI. Ultrasonographic examinations were done in all cows at the second PGF2α injection of presynchronization, initial GnRH injection, PGF2α injection of Ovsynch, at TAI, and 24 h after TAI for cyclicity status and ovarian responses to treatments, and at 32 and 60 d after TAI for confirmation of pregnancy. Overall, 29 cows (10.7%) were determined acyclic or cystic and excluded from the study. The percentage of cows responding to initial GnRH injection (62.2 vs. 61.5%) did not differ between PRE-9 and PRE-12 but more cows in the PRE-9 group failed to respond to PGF2α treatment of Ovsynch compared with PRE-12 (22.7 vs. 10.7%). Body condition score at TAI (2.9±0.02) and mean ovulatory follicle diameter (16.4±0.2 mm) were not different between treatments. Overall P/AI at 32 d was reduced in PRE-9 (33.6%) compared with PRE-12 (44.3%) but pregnancy losses (5.0 vs. 3.7%) did not differ between treatments. Primiparous cows in the PRE-12 group had higher mean progesterone concentration 11 d after TAI and greater P/AI 32 after TAI than primiparous cows in the PRE-9 group (6.4±0.5 vs. 4.6±0.5 ng/mL and 55.8 vs. 30.0%, respectively). In conclusion, reducing the interval from the last PGF2α injection of the presynchronization treatment to initiation of Ovsynch (from 12 to 9 d) did not affect ovulatory response to initial GnRH injection but reduced response to PGF2α injection of Ovsynch and P/AI at 32 and 60 d after TAI.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Pregnancy

The objective of this study was to determine the effect of timing of artificial insemination on pregnancy rates, calving rates, abortion rates, twinning rates, and calf gender ratio after synchronization of ovulation with Ovsynch protocol in Holstein dairy cows. The ovulation of 219 lactating Holstein dairy cows was synchronized using the Ovsynch protocol. Therefore, cows received an injection of GnRH followed by an injection of prostaglandin F(2α) 7 days later and a second treatment with GnRH 2 days later. Cows were artificially inseminated at 0, 12, or 24 h after the second injection of GnRH. Reproductive performance did not differ between cows inseminated at 0 h (n = 82), 12 h (n = 66), or 24 h (n = 71) after the last injection of GnRH (pregnancy rate: 0 h 48 %, 12 h 47 %, 24 h 52 %; abortion rate: 0 h 5 %, 12 h 0 %, 24 h 11 %; calving rate: 0 h 43 %, 12 h 47 %, 24 h 41 %; twinning rate: 0 h 2 %, 12 h 0 %, 24 h 0 %; calf gender ratio (F/M): 0 h 61:39 %, 12 h 48:52 %, 24 h 39:61 %; P > 0.05). Pregnancy rates for cows inseminated in postpartum times of 50-75, 76-100, and >100 days within the first and ≥ 3 parities were statistically similar (P > 0.05), but pregnancy rates for cows inseminated at different postpartum times of 50-75, 76-100, and >100 days within the second parity were different (P < 0.01). In general, pregnancy rates of cows inseminated at different postpartum times (P < 0.01) and parities (P < 0.001) differed. The findings of the current study showed that rates of pregnancy, abortion, calving, and twinning of Holstein dairy cows subjected to artificial insemination at different times after synchronization were similar. These results also indicate that the timing of artificial insemination after synchronization did not influence calf gender ratio. Furthermore, pregnancy rates of Holstein dairy cows inseminated after synchronization were significantly influenced by postpartum time and parity number.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Chi-Square Distribution; Dairying; Dinoprost; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Logistic Models; Ovulation; Ovulation Induction; Pregnancy; Pregnancy Rate; Reproduction; Sex Ratio; Time Factors; Turkey

Ascending placentitis results in premature birth and high foal mortality. By understanding how placentitis induces premature delivery, it may be possible to develop diagnostic markers and to delay premature delivery pharmacologically, thereby decreasing perinatal foal mortality.. To identify relationships between bacterial infection, inflammation and premature parturition in mares with experimentally induced placentitis.. Experiment 1: Concentrations of allantoic fluid prostaglandins (PGs) F2alpha and E2 were measured in 8 mares after intracervical inoculation with Streptococcus equi ssp. zooepidemicus (at Days 285-291 of gestation) until parturition and compared with controls (n = 4). Experiment 2: mRNA expression of interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF)-alpha and IL-8 in the chorioallantois from inoculated mares in Experiment 1 were compared with 7 mares that foaled normally.. Bacterial inoculation resulted in 7 aborted fetuses and birth of one premature, viable foal. Infection was associated with inflammation of the chorioallantois in the region of the cervical star, isolation of bacteria and high concentrations of PGE2 and PGF2alpha in allantoic fluid obtained within 48 h of delivery (P = 0.04). Chorioallantois from all mares expressed mRNA for IL-8, TNF-alpha, IL-6 and IL-1beta. Experimentally infected mares expressed more mRNA for IL-6 (P = 0.003) and IL-8 (P = 0.009) in the cervical star region and more mRNA for IL-6 (P = 0.004) in tissues from placental horns than control mares.. Bacterial placentitis may result in liberation of cytokines from the chorioallantois and prostaglandin formation leading to abortion or birth of a precociously mature foal.

Topics: Abortion, Veterinary; Animals; Bacterial Infections; Cytokines; Dinoprost; Dinoprostone; Female; Gene Expression Regulation; Horse Diseases; Horses; Inflammation; Placenta; Placenta Diseases; Pregnancy; Pregnancy Complications, Infectious; Premature Birth; RNA, Messenger

Content The objective of the study was to investigate whether a treatment with hCG 4 days after AI could reduce pregnancy losses in lactating dairy cows. Cows of a dairy herd presented to the veterinarian in a fixed reproductive management protocol were treated with an Ovsynch protocol if no corpus luteum (CL) could be palpated per rectum (Group OV). Cows with a CL received cloprostenol (0.15 mg). After 2 days, these cows were treated with buserelin (0.01 mg) and received timed AI 16-20 h later (Group PG). In both treatment protocols, cows were assigned to two groups to receive 2500 IU of hCG i.v. 4 days after AI or to serve as untreated controls (Groups OV-hCG, OV-Control, PG-hCG and PG-Control). Pregnancy diagnosis was carried out 27 days after AI via ultrasonography and 39 days after AI by rectal palpation. Pregnancy losses were defined as cows being pregnant on day 27 but not pregnant on day 39 after AI. Pregnancy rate (PR) by day 27 did not differ among the four groups (35.4, 35.0, 37.0 and 38.0% for Groups OV-hCG, OV-Control, PG-hCG and PG-Control, respectively). Pregnancy losses between day 27 and day 39 after AI were smaller in hCG treated animals in summer but not in autumn and spring. Pregnancy rate by day 39 after AI was higher in PG than in OV groups, but independent of hCG-treatment. In conclusion, treatment with hCG 4 days after AI did not significantly increase PR on 39 days after AI. A positive effect of hCG on pregnancy losses during the summer months warrants further investigation.

Topics: Abortion, Veterinary; Animals; Buserelin; Cattle; Chorionic Gonadotropin; Cloprostenol; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Logistic Models; Ovulation Induction; Pregnancy; Pregnancy Rate; Progesterone; Seasons; Time Factors

Mummification of bovine fetuses is an uncommon condition, and cows do not always respond to treatment with prostaglandin F2alpha. The objective of the present retrospective and descriptive case study was to determine the conception rate and survival time of nonresponsive, prostaglandin F2alpha (PGF2alpha)-treated cows (n = 14), following hysterotomy or medical treatment and manual removal. Animal records from 1990 to 2005 from the Centre Hospitalier Universitaire Vétérinaire (CHUV) of the Université de Montréal were studied. Inclusion criteria were the nonexpulsion of the mummified fetus following PF2alpha treatment and absence of concomitant conditions upon physical examination. Of the animals included in the study, 36% (n = 5) became pregnant after extraction of the mummified fetus by hysterotomy and 0% conceived after medical treatment and manual extraction. In this study, hysterotomy represented an effective approach for extracting mummified fetuses from cows that did not respond to PF2alpha treatment.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Female; Fertility; Fetal Death; Fetus; Hysterotomy; Pregnancy; Retrospective Studies

This experiment was designed to compare pregnancy rates in postpartum beef cows resulting from fixed-time AI (FTAI) after treatment with 1 of 2 protocols to synchronize estrus and ovulation. Cross-bred, suckled beef cows (n = 650) at 4 locations (n = 210; n = 158; n = 88; and n = 194) were assigned within a location to 1 of 2 protocols within age group by days postpartum and BCS. Cows assigned to the melengestrol acetate (MGA) Select treatment (MGA Select; n = 327) were fed MGA (0.5 mg x head(-1) x d(-1)) for 14 d, GnRH (100 microg of Cystorelin i.m.) was injected on d 26, and prostaglandin F2alpha (PG; 25 mg of Lutalyse i.m.) was injected on d 33. Cows assigned to the CO-Synch + controlled internal drug release (CIDR) protocol (CO-Synch + CIDR; n = 323) were fed a carrier for 14 d, were injected with GnRH and equipped with an EAZI-BREED CIDR insert (1.38 g of progesterone, Pfizer Animal Health, New York, NY) 12 d after carrier removal, and PG (25 mg of Lutalyse i.m.) was injected and the CIDR were removed on d 33. Fixed-time AI was performed at 72 or 66 h after PG for the MGA Select or CO-Synch + CIDR groups, respectively. All cows were injected with GnRH (100 microg of Cystorelin i.m.) at the time of insemination. Blood samples were collected 8 and 1 d before the beginning of MGA or carrier to determine estrous cyclicity status of the cows (estrous cycling vs. anestrus) before treatment [progesterone > or = 0.5 ng/mL (MGA Select, 185/327, 57%; CO-Synch + CIDR, 177/323, 55%); P = 0.65]. There was no difference (P = 0.20) in pregnancy rate to FTAI between treatments (MGA Select, 201/327, 61%; CO-Synch + CIDR, 214/323, 66%). There was also no difference (P = 0.25) between treatments in final pregnancy rate at the end of the breeding period (MGA Select, 305/327, 93%; CO-Synch + CIDR, 308/323, 95%). These data indicate that pregnancy rates to FTAI were comparable after administration of the MGA Select or CO-Synch + CIDR protocols. Both protocols provide opportunities for beef producers to utilize AI and potentially eliminate the need to detect estrus.

Topics: Abortion, Veterinary; Administration, Oral; Animal Husbandry; Animals; Cattle; Dinoprost; Drug Implants; Estrus Synchronization; Female; Fertility Agents, Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Melengestrol Acetate; Ovulation; Postpartum Period; Pregnancy; Pregnancy Rate; Progesterone

Our objective was to assess the effect of pretreatment with PGF(2alpha) 12 d before initiation of a protocol for resynchronization of ovulation (Resynch) using an Ovsynch protocol. Lactating Holstein cows diagnosed not pregnant 31 d after a timed artificial insemination (TAI) were randomly assigned to initiate the Resynch protocol 32 d after TAI (n = 255; RES), or receive 25 mg of PGF(2alpha) 34 d after TAI and initiate the Resynch protocol 12 d later at 46 d after TAI (n = 272; PGF+RES). Within each treatment, a subset of cows were examined using transrectal ultrasonography to determine ovulatory response to the first GnRH injection of the Resynch protocols or a blood sample was collected to determine serum progesterone (P(4)) at initiation of the Resynch protocol, or both. Overall, PGF+RES cows had more pregnancies per artificial insemination (P/AI) than RES cows 66 d after TAI (35.2 vs. 25.6%), whereas pregnancy loss from 31 to 66 d after TAI was greater for RES than PGF+RES cows (17.1 vs. 7.6%). Although P/AI was greater for cows with high (>/=1.0 ng/mL) vs. low (<1.0 ng/mL) P(4) at the first GnRH injection of the Resynch protocols, treatment did not affect the proportion of cows with low P(4) at the first GnRH injection of the Resynch protocols. Overall, no effect of treatment on ovulatory response to the first GnRH injection of the Resynch protocols was detected. We conclude that pretreatment with PGF(2alpha) 12 d before initiation of the Resynch protocol increased P/AI 66 d after TAI for cows with serum P(4) concentration >1.0 ng/mL at the first GnRH injection of the Resynch protocol and decreased pregnancy loss from 31 to 66 d after TAI. This modified resynchronization protocol may be a useful strategy for reproductive management of lactating dairy cows.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Female; Fertility; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovulation; Ovulation Induction; Pregnancy; Pregnancy Outcome; Pregnancy Rate; Progesterone; Random Allocation; Time Factors

In order to evaluate the efficacy, the safety and the variation in plasma concentrations of estrogens, progesterone, PGFM, oxytocin, cortisol and prolactin after mid-pregnancy termination induced by aglepristone, 61 pregnant queens (33.3 + 4.2 days), were injected subcutaneously with 15 [corrected] mg/kg aglepristone, (Alizine) [corrected] repeated once 24 h later. Five queens served as control and received a placebo. The efficacy of aglepristone was 88.5% and termination of pregnancy was achieved in 50% of the queens within 3 days. Brief periods of depression and anorexia were noted in 9.3% of the queens before fetal expulsion (these symptoms were attributed to the phenomenon of fetal expulsions). Not one of the queens that aborted developed uterine disease. There were no changes in plasma concentrations of estrogen, prostaglandin, prolactin or oxytocin following aglepristone administration. However, there were significant increases in plasma concentrations of progesterone and cortisol 60 and 30 h, respectively, after aglepristone administration. Termination of pregnancy occurred with high plasma progesterone concentrations. Fetal expulsion was characterised by an increase in estrogen, PGFM and oxytocin concentrations, whereas prolactin and cortisol levels remained at a basal level.

Topics: Abortifacient Agents, Steroidal; Abortion, Induced; Abortion, Veterinary; Animals; Cats; Dinoprost; Estrenes; Estrogens; Female; Male; Oxytocin; Pregnancy; Progesterone

Our objective was to determine whether progesterone (P4) supplementation during an Ovsynch protocol would enhance fertility in lactating dairy cows. Lactating dairy cows (n = 634) at 6 locations were assigned randomly within lactation number and stage of lactation to receive the Ovsynch protocol [OVS; synchronization of ovulation by injecting GnRH 7 d before and 48 h after PGF(2alpha), followed by one fixed-time AI (TAI) 16 to 20 h after the second GnRH injection] or Ovsynch plus a controlled internal drug release (CIDR) P4-releasing insert for 7 d, beginning at the first GnRH injection (OVS + CIDR). Blood was sampled to quantify P4 10 d before the first GnRH injection, immediately before the first GnRH injection, at the time of CIDR removal, before the PGF(2alpha) injection (1 to 2 h after CIDR insert removal), and 48 h after the PGF(2alpha) injection to determine cyclicity status before initiation of treatment, luteal status at the PGF(2alpha) injection, and incidence of luteal regression. Overall, conception rates at 28 (40 vs. 50%) and 56 d (33 vs. 38%) after TAI differed between OVS and OVS + CIDR, respectively; but a treatment x location interaction was detected. Compared with OVS, pregnancy outcomes were more positive for OVS + CIDR cows at 4 of 6 locations 28 d after TAI and at 3 of 6 locations 56 d after TAI. An interaction of luteal status (high vs. low) before CIDR insert removal and PGF(2alpha) injection with pretreatment cycling status indicated that cows having low P4 at PGF(2alpha) injection benefited most from P4 supplementation (OVS + CIDR = 36% vs. OVS = 18%), regardless of pretreatment cycling status. Pregnancy loss between 28 and 56 d after TAI was greater for noncycling cows (31%) compared with cycling cows (16%). Pregnancy loss for cows receiving P4 (21%) did not differ from that for cows not receiving P4 (21%). Supplementation of P4, pretreatment cycling status, and luteal status before PGF(2alpha) injection altered follicular diameters at the time of the second GnRH injection, but were unrelated to pregnancy outcomes. Incidence of multiple ovulation was greater in noncycling than in cycling cows. Further, cows having multiple ovulations had improved pregnancy outcomes at 28 and 56 d after TAI. In summary, a CIDR insert during the Ovsynch protocol increased fertility in lactating cows having low serum P4 before PGF(2alpha) injection. Improved pregnancy outcomes were observed at some, but not all locations.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrous Cycle; Female; Gonadotropin-Releasing Hormone; Illinois; Insemination, Artificial; Kansas; Lactation; Michigan; Missouri; Ohio; Ovarian Follicle; Ovulation Induction; Pregnancy; Pregnancy Outcome; Progesterone; Wisconsin

This study examined the influence of a GnRH agonist containing either 450 or 750 microg of deslorelin in an implant form or a gonadorelin injection (control) to induce ovulation in the Ovsynch protocol on pregnancy rates (PR), embryonic loss, and ovarian function in 593 lactating Holstein cows. Cows were given two injections of PGF2alpha 14 days apart, followed 14 days later by the Ovsynch protocol, and were timed artificially inseminated (TAI) at 68 +/- 3 days postpartum. Blood samples for determination of plasma progesterone concentrations were collected at 24 and 10 days prior to and 11 days after TAI. Pregnancy was diagnosed on Day 27 and reconfirmed on Day 41 after TAI. Non-pregnant, not re-inseminated cows at Day 27 had their ovaries examined by ultrasonography, and the number and size of follicles and presence of luteal tissue were determined. Simultaneously, these cows were re-synchronized with the Ovsynch protocol. Pregnancy during the re-synchronization period was determined between 35 and 41 days after insemination. On Day 27, PR were higher for control (39.0%) and deslorelin 450 microg (DESLORELIN 450) implant (41.3%) than for those receiving the deslorelin 750 microg (DESLORELIN 750) implant (27.5%; P<0.05). Pregnancy losses tended to decrease for DESLORELIN 450 compared with control (5.0% versus 12.7%; P<0.13). Plasma progesterone concentrations did not differ significantly among treatments. Deslorelin suppressed ovarian activity and decreased PR during the re-synchronization period compared with control. The percentage of non-pregnant animals that were re-inseminated by Day 27 was less for deslorelin compared with control. In conclusion, incorporation of an implant of the GnRH agonist deslorelin to induce ovulation in the Ovsynch protocol has the potential to reduce pregnancy losses, but the response was dependent upon implant concentration. Evaluation of lower doses to minimize the negative effects on subsequent fertility is warranted.

Topics: Abortion, Veterinary; Animals; Cattle; Corpus Luteum; Dinoprost; Drug Implants; Estrus Synchronization; Female; Insemination, Artificial; Lactation; Ovarian Follicle; Ovary; Pregnancy; Progesterone; Reproduction; Time Factors; Triptorelin Pamoate; Ultrasonography

The purpose of this study was to describe the findings and therapy in 4 cows and 1 heifer with mummified fetus. All animals were admitted at the clinic after several unsuccessful therapies with prostaglandin F2alpha and local uterine infusions. All animals were in good condition. In case 1, diagnosis of mummified fetus could not be confirmed after manual rectal palpation and ultrasonography whereas cases 2, 4, 5 all had mummified fetus. In case 3, the fetus was in maceration. Initial therapy consisted of administration of prostaglandin F2alpha and prostaglandin E2 followed by repeated administration of prostaglandin E2. Mummies (length from apex to rump 13-32 cm) could be taken out within 3 to 6 days per vias naturales in cases 2, 4, 5 and in case 3, bones (maximal length 4 cm) could be unhinged. The structure in the uterus of case 1 could not be mobilised and was consequently removed under sight control using colpotomy followed by hysterotomy. Animals 2, 3, 4 and 5 were pregnant on the occasion of telephone inquiry. On the basis of our results, we recommend the conservative medical therapy with PGE2 for cases of mummified fetus. Colpotomy and hysterotomy are reserved as therapy feasible if the use of prostaglandin E2 is not successful.

Topics: Abortion, Veterinary; Animals; Cattle; Colpotomy; Dinoprost; Dinoprostone; Female; Fetal Death; Fetus; Hysterotomy; Pregnancy

Inoculation with Actinomyces pyogenes and administration of prostaglandin (PG)F(2alpha) were used to induce late embryonic mortality (LEM) in heifers (n=8) on Days 30-38 of pregnancy in order to compare the profile for bovine pregnancy associated glycoprotein 1 (PAG1), progesterone and 15-keto-13,14-dihydro-PGF(2alpha) (PGFM). Two pregnant heifers were used as controls. Inoculation into the uterine body caused LEM, as established by ultrasonography in each heifer within 24h of treatment. When the inoculum was injected into the first part of the cervix, LEM occurred in one of two heifers (Heifer A) between 48 and 72 h after treatment. Similarly, PGF(2alpha) treatment caused LEM in three of four heifers. In six of eight heifers, PAG1 started to decrease steadily when it was accompanied by the subsequent death of the embryo. Inoculation through the cervix caused luteolysis in three of four heifers within 6-10 days after induction. After induction of LEM, PGFM concentrations showed a two to 3.8 fold increase in three of four heifers during the following six days, and from that time changed within normal ranges. The results of this study indicate that a PAG1 assay may provide an alternative method to ultrasonography for determining LEM in the cow.

Topics: Abortion, Veterinary; Actinomyces; Animals; Aspartic Acid Endopeptidases; Biomarkers; Cattle; Diagnosis, Differential; Dinoprost; Female; Fetal Death; Pregnancy; Pregnancy Proteins; Pregnancy, Animal

An intravaginal progesterone insert (CIDR insert; 1.38 g of progesterone) was evaluated for synchronization of returns to estrus (SR), conception rate (CR), and pregnancy rate (PR) in dairy cows previously artificially inseminated (AI). Healthy, nonpregnant, lactating Holstein cows, > or = 40 and < or = 150 d postpartum at eight commercial farms were used. Cows detected in estrus and receiving AI 2, 3, or 4 d after one injection of PGF2alpha (25 mg) were assigned as either controls (n = 945), or to receive a CIDR insert (n = 948) for 7 d (14 to 21 +/- 1 d after AI). Cows were observed for returns to estrus from 18 to 26 +/- 1 d after initial AI (resynchrony period) and were reinseminated if in estrus. Vaginal mucus on CIDR inserts (97.3% retention) at removal was scored: 1 = no mucus; 2 = clear; 3 = cloudy; 4 = yellow; and 5 = red or brown. Percentage of cows in estrus (SR) during the 3 d after CIDR insert removal was contrasted to the highest 3-d cumulative percentage in estrus for controls. Cows conceiving to initial AI were omitted in calculations of SR, CR, and PR during resynchrony. Mucous scores of 3 or 4 (mild irritation) were observed in 65% of cows and a score of 5 (more severe irritation) was observed in 2%; otherwise, health was unaffected. The PR to initial AI was lower for cows subsequently receiving CIDR inserts than for controls (32.7 vs. 36.7%). The CIDR insert increased SR (34.1 vs. 19.3% in 3 d) and overall estrus detection (43% in 4 d vs. 36% in 9 d) compared with controls. For the 9-d resynchrony period, CR and PR for CIDR-treated (26.7, 12.2%) and control (30.9, 11.1%) cows did not differ significantly. The CIDR inserts improved synchrony of returns to estrus, slightly reduced PR to initial AI, but did not affect CR or PR to AI during the resynchrony period.

Topics: Abortion, Veterinary; Administration, Intravaginal; Animals; Cattle; Cattle Diseases; Cervix Mucus; Dinoprost; Estrus Synchronization; Female; Fertilization; Insemination, Artificial; Lactation; Pregnancy; Progesterone

Seven bitches in early pregnancy (12.8 +/- 3.8 days after ovulation; group 1) and seven bitches in mid-pregnancy (32.0 +/- 1.53 days after ovulation; group 2) were used in this study. For each group, five bitches were treated with 0.10 mg aglepristone (Alizine) kg-1 and this dose was repeated 24 h later. Two control bitches received a placebo. Blood samples were collected at 6 h intervals to determine plasma concentrations of progesterone, dihydro-keto prostaglandin F2 alpha (PGFM), oxytocin, prolactin and cortisol. Parturition occurred in the four control bitches. All bitches treated with aglepristone aborted. In group 1, embryonic death occurred; in group 2, fetal expulsion occurred 60-132 h after administration of aglepristone. After pregnancy termination, the interoestrous interval of aglepristone-treated bitches was significantly shorter than that before treatment. Treatment with aglepristone did not modify plasma concentrations of progesterone, prostaglandin, oxytocin or cortisol within 24 h after its administration, but it induced, in mid-pregnancy (group 2) a discharge of prolactin within 12 h after its administration. As an abortifacient, aglepristone acted on the uterus and, therefore, did not have direct or immediate luteolytic properties. Termination of pregnancy occurred with high plasma progesterone concentrations. Fetal expulsion was characterized by an increase in the concentration of PGFM, but oxytocin and cortisol remained at basal concentrations.

Topics: Abortifacient Agents; Abortion, Induced; Abortion, Veterinary; Animals; Dinoprost; Dogs; Estrenes; Female; Gestational Age; Hormones; Hydrocortisone; Oxytocin; Pregnancy; Progesterone; Prolactin; Random Allocation

Topics: Abortion, Veterinary; Animals; Corpus Luteum; Dinoprost; Enzyme-Linked Immunosorbent Assay; Female; Horses; Hydroxyprogesterones; Luteolytic Agents; Medroxyprogesterone; Megestrol; Pregnancy; Pregnancy Outcome; Pregnenediones; Progesterone; Progesterone Congeners; Random Allocation; Trenbolone Acetate

A 19-year-old Quarter Horse mare was evaluated because of bloody vaginal discharge that was apparent immediately following breeding. On transrectal ultrasonography, it was evident that the uterus was filled with fluid containing echogenic particles; linear hyperechoic structures were also visible. Endoscopy was performed, which revealed a number of bones adhered to the cranial wall and floor of the right uterine horn as well as purulent fluid in both uterine horns. Bacterial endometritis and fetal maceration were diagnosed. The mare was treated with antibiotics, and the fetal bones were manually removed from the uterus. Fetal maceration with intrauterine retention of bones is rare in mares. Use of hysteroscopy supplements ultrasonography in the diagnosis of uncommon conditions of the uterus. Macerated bones may be adhered to the endometrium, thereby requiring manual removal.

Topics: Abortion, Veterinary; Animals; Bone and Bones; Cattle; Dinoprost; Endometritis; Female; Fetus; Horse Diseases; Horses; Hysteroscopy; Oxytocics; Pregnancy; Progesterone; Streptococcal Infections; Streptococcus equi; Trimethoprim, Sulfamethoxazole Drug Combination; Ultrasonography; Uterus; Vaginal Discharge

Groups of five pregnant bitches were treated to terminate the pregnancy with four combinations of drugs, starting 28 days after the estimated surge of luteinising hormone (LH), 22 to 28 days after the first mating. The treatments were: cabergoline administered orally for 10 days at a dose of 5 micrograms/kg and a single subcutaneous injection of 2.5 micrograms/kg cloprostenol at the start of the treatment; the same dose of cabergoline plus two doses of 1 microgram/kg cloprostenol administered on days 28 and 32 after the LH surge; bromocryptine administered orally at a dose of 30 micrograms/kg three times a day for 10 days plus a single dose of 2.5 micrograms/kg cloprostenol; the same dose of bromocryptine plus two doses of 1 microgram/kg cloprostenol; and a group of five pregnant bitches was left untreated. The pregnancies were terminated in all but one of the treated bitches, in each case by resorption of the fetuses. There were few side effects in the bitches treated with two doses of 1 microgram/kg cloprostenol, and were present but acceptable in those treated with one dose of 2.5 micrograms/kg. Plasma progesterone concentrations decreased to less than 1 ng/ml within 72 hours of the start of treatment and remained low except in the bitch in which pregnancy was not terminated. In the five untreated bitches, plasma progesterone remained high and they whelped normally. In the treated groups, the intervals between successive displays of oestrus were reduced by approximately 70 days in comparison with previous cycles or with the control group, but the fertility of the dogs was not affected adversely.

Topics: Abortion, Veterinary; Animals; Dinoprost; Dogs; Dopamine Agonists; Drug Administration Schedule; Estrus; Female; Fertility; Pregnancy; Progesterone

To investigate the causes and mechanisms of foetal loss in Norwegian dairy goats, blood parameters in 40 goats that lost foetuses were compared with those in 40 goats that experienced a normal pregnancy. High mean levels of 15-ketodihydro-PGF2alpha, and low mean levels of oestrone sulphate throughout pregnancy were associated with foetal loss. The mean oestrone sulphate level was low before abortion, and the distinct peak that occurred at parturition in the control goats was not observed in connection with abortion. Association of other blood parameters with foetal loss was not detected. Infectious agents and toxins did not appear to be major causes of foetal loss in this study. The normal level of progesterone and cortisol in goats with foetal loss indicated that the function of the corpus luteum and adrenal glands, respectively, were not disturbed. The rapid decline in progesterone level associated with foetal loss may therefore be a result, rather than the cause, of foetal death. The lowered level of oestrone sulphate and elevated level of 15-ketodihydro-PGF2alpha in goats with foetal loss clearly indicated that the endocrine foetal-placental function was disturbed.

Topics: Abortion, Veterinary; Adrenal Glands; Animals; Blood Proteins; Case-Control Studies; Corpus Luteum; Dinoprost; Enzyme-Linked Immunosorbent Assay; Estrone; Female; gamma-Glutamyltransferase; Glutamate Dehydrogenase; Goats; Hydrocortisone; Male; Norway; Placenta; Pregnancy; Pregnancy Outcome; Progesterone; Radioimmunoassay; Serum Albumin; Serum Globulins

Disseminated eosinophilic myositis was diagnosed in an alpaca that had been imported to the USA from Peru 5 years earlier. The myositis was associated with macroscopically visible large sarcocysts that were characterized histologically by septate compartments containing bradyzoites, and ultrastructurally by cyst walls composed of anastomosing villous protrusions. Two hours before death, the alpaca aborted an 8-month-gestation fetus, but no lesions were found in the uterus, placenta or fetus. Additional macroscopical findings included haemoabdomen and myofibre haemorrhage, degeneration and necrosis. It is believed that this is the first described case of clinical disease associated with a Sarcocystis sp. (probably S. aucheniae) in camelids.

Topics: Abortion, Veterinary; Animals; Camelids, New World; Dinoprost; Eosinophilia; Fatal Outcome; Female; Microscopy, Electron; Muscle, Skeletal; Myositis; Pregnancy; Protozoan Infections, Animal; Sarcocystosis

Ewes were lutectomized and treatments were started 72 h later. Pregnant ewes were treated with vehicle; prostaglandin F2alpha (PGF2alpha); cortisol (C); trilostane (TR), a 3beta-hydroxy-steroid dehydrogenase inhibitor; PGF2alpha + C; TR + PGF2alpha; TR + C, or TR + PGF2 + C. TR, TR + PGF2alpha, TR + C, and TR + PGF2alpha + C aborted (P < or = 0.05) all ewes receiving TR. One ewe treated with PGF2alpha aborted (P > or = 0.05). The average time to abortion of TR-treated ewes was 50.8 h (P < or = 0.05) after initiation of treatments. All aborted ewes had retained placentas (P < or = 0.05) except one ewe in the TR + PGF2alpha, treatment group. TR was given every 12 h starting at 72 h postlutectomy until 96 h postlutectomy. TR reduced (P < or = 0.05) progesterone. Estradiol-17beta was increased (P < or = 0.05) 2 h after the first two TR treatments and declined 2 h later and was followed by a sustained increase (P < or = 0.05) in estradiol-17beta, which was coincident with the onset of abortions. Estradiol-17beta was increased (P < or = 0.05) by PGF2alpha but did not decrease (P > or = 0.05) placental secretion of progesterone. It is concluded that TR but not PGF2alpha is an abortifacient in 90-day-pregnant lutectomized ewes and that abortion occurs only when there is a decrease in circulating progesterone and an increase in circulating estradiol-17beta.

Topics: 3-Hydroxysteroid Dehydrogenases; Abortifacient Agents, Steroidal; Abortion, Induced; Abortion, Veterinary; Animals; Corpus Luteum; Dihydrotestosterone; Dinoprost; Enzyme Inhibitors; Estradiol; Female; Hydrocortisone; Organ Size; Placenta; Pregnancy; Pregnancy, Animal; Progesterone; Sheep; Time Factors

One objective of this experiment was to evaluate our hypotheses that estradiol-17beta regulates secretion of pregnancy specific protein B (PSPB) and that secretion of progesterone during pregnancy is regulated by a prostanoid by examining the effects of prostaglandin F2alpha (PGF2alpha), a luteolyic agent; indomethacin, a prostanoid synthesis inhibitor; tamoxifen, an estrogen receptor antagonist; estradiol 17-beta; and interaction of these factors on the incidence of abortion and progesterone and PSPB secretion. Another objective was to determine if there is a luteal source of PSPB. Weights of corpora lutea were decreased (P < or = 0.05) by PGF2alpha, indomethacin, PGF2alpha + tamoxifen, PGF2alpha + indomethacin, and PGF2alpha + estradiol-17beta but not (P > or = 0.05) by tamoxifen or estradiol-17beta alone. No ewe treated with PGF2alpha alone aborted (P > or = 0.05). Forty percent of ewes treated with PGF2alpha + estradiol-17beta aborted (P < or = 0.05), but ewes were not aborted by any other treatment within the 72-h sampling period. Profiles of progesterone in jugular venous blood differed (P < or = 0.05) among control, indomethacin-, tamoxifen-, and PGF2alpha + indomethacin-treated ewes. Progesterone in jugular venous blood of control ewes decreased (P < or = 0.05) by 24 h, followed by a quadratic increase (P < or = 0.05) from 24 to 62 h. Progesterone in jugular venous blood of indomethacin-, PGF2alpha-, PGF2alpha- + tamoxifen-, PGF2alpha + indomethacin-, PGF2alpha + estradiol-17beta-, and tamoxifen-treated ewes was reduced (P < or = 0.05) by 18 h and did not vary (P > or = 0.05) for the remainder of the 72-h sampling period. Progesterone in vena cava and in uterine venous blood was reduced (P < or = 0.05) at 72 h in PGF2alpha-, indomethacin-, tamoxifen-, PGF2alpha + indomethacin-, PGF2alpha + tamoxifen-, and PGF2alpha + estradiol-17beta-treated ewes. Weights of placentomes did not differ among treatment groups (P > or = 0.05). Profiles of PSPB in inferior vena cava blood differed (P < or = 0.05) among control, estradiol-17beta-, indomethacin-, tamoxifen-, PGF2alpha + indomethacin-, and PGF2alpha + tamoxifen-treated 88- to 90-day pregnant ewes. Concentrations of PSPB in inferior vena cava blood were increased (P < or = 0.05) in indomethacin-, estradiol-17beta-, tamoxifen-, PGF2alpha + tamoxifen-, and PGF2alpha + indomethacin-treated 88- to 90-day pregnant ewes within 6 h and did not vary (P > or = 0.05) for the remainder of the 72-h sampling period. C

Topics: Abortifacient Agents, Steroidal; Abortion, Induced; Abortion, Veterinary; Animals; Aspartic Acid Endopeptidases; Corpus Luteum; Dinoprost; Estradiol; Female; Gestational Age; Indomethacin; Organ Size; Placenta; Pregnancy; Pregnancy Proteins; Progesterone; Sheep; Tamoxifen; Tocolytic Agents; Uterus

Ninety-day pregnant sheep were ovariectomized and received vehicle or trilostane every 12 h through 132 h, starting at 72 h postovariectomy. All trilostane-treated ewes aborted (P < or = 0.05) between 36 and 50 h after initiation of treatment. Profiles of progesterone in jugular venous blood differed (P < or = 0.05) and was lower (P < or = 0.05) in trilostane-treated ewes. Profiles of estradiol-17beta in jugular venous plasma of trilostane-treated ewes differed (P < or = 0.05) from controls. Estradiol-17beta increased after the first two treatments, followed by a return 2 h later to pretreatment levels (P > or = 0.05), which was followed by a sustained increase (P < or = 0.05) in estradiol-17beta. Profiles of PGF2alpha in inferior vena cava plasma of trilostane-treated ewes differed and were greater (P < or = 0.05) and occurred with the sustained increase in estradiol-17beta and the onset of most of the abortions. Profiles of PGE in inferior vena cava plasma between control and trilostane-treated 90-day pregnant ewes did not differ (P > or = 0.05). It is concluded that abortions occur at midpregnancy in sheep when the estradiol-17beta : progesterone ratio changes sufficiently to cause a sustained increase in estradiol-17beta and PGF2alpha but without changing placental secretion of PGE.

Topics: Abortifacient Agents, Steroidal; Abortion, Veterinary; Animals; Dihydrotestosterone; Dinoprost; Female; Ovariectomy; Pregnancy; Pregnancy, Animal; Progesterone; Prostaglandins E; Sheep; Time Factors

Treatment with PGF2alpha plus estradiol-17beta aborts 90-day pregnant ewes, whereas PGF2alpha or estradiol-17beta alone does not abort ewes. The objective of this experiment was to evaluate whether tamoxifen, an estrogen receptor antagonist, estradiol-17beta, prostaglandin F2alpha (PGF2alpha), indomethacin, or some of their interactions affected ovine uterine/placental secretion of PGF2alpha, estradiol-17beta or prostaglandins E (PGE), because a single treatment with PGF2alpha and estradiol-17beta given every 6 h aborts 90-day pregnant ewes. Concentrations of PGF2alpha in uterine venous blood were increased (P < or = 0.05) by estradiol-17beta, PGF2alpha + estradiol-17beta, and PGF2alpha + tamoxifen, and decreased (P < or = 0.05) by indomethacin or PGF2alpha + indomethacin at 72 h when compared to the 0 h samples. Concentrations of PGE in uterine venous blood were decreased (P < or = 0.05) by indomethacin and PGF2alpha + indomethacin and increased (P < or = 0.05) by PGF2alpha + estradiol-17beta at 72 h when compared to the 0 h samples. Concentrations of PGF2alpha in inferior vena cava blood at 6 h were increased (P < or = 0.05) by PGF2alpha either alone or in combination with indomethacin, tamoxifen, or estradiol-17beta, which is due to the PGF2alpha injected. Concentrations of PGF2alpha in inferior vena cava blood in PGF2alpha + estradiol-17beta-treated 88- to 90-day pregnant ewes increased (P < or = 0.05) linearly over the 72-h sampling period and averaged 4.0 + 0.4 ng/ml. Concentrations of PGF2alpha in inferior vena cava blood of control, PGF2alpha, tamoxifen, PGF2alpha + indomethacin, PGF2alpha + tamoxifen, and estradiol-17beta-treated ewes did not differ (P > or = 0.05) and averaged 0.4 + 0.04 ng/ml. Profiles of PGE in inferior vena cava blood of 88- to 90-day pregnant ewes treated with vehicle, PGF2alpha, estradiol-17beta, tamoxifen, tamoxifen + PGF2alpha, or estradiol-17beta + PGF2alpha did not differ (P > or = 0.05). Concentrations of PGE in inferior vena cava blood of 88- to 90-day pregnant ewes treated with indomethacin or PGF2alpha + indomethacin were lower (P < or = 0.05) than in control ewes. Concentrations of estradiol-17beta in jugular venous plasma of PGF2alpha + estradiol-17beta-treated 88- to 90-day pregnant ewes increased linearly and differed (P < or = 0.05) from controls. Profiles of estradiol-17beta in jugular venous plasma of PGF2alpha, indomethacin, tamoxifen, and PGF2alpha + tamoxifen and PGF2alpha + indomethacin, estradiol-17beta,

Topics: Abortifacient Agents, Steroidal; Abortion, Induced; Abortion, Veterinary; Animals; Dinoprost; Estradiol; Female; Indomethacin; Pregnancy; Pregnancy, Animal; Prostaglandins E; Sheep; Tamoxifen; Time Factors; Tocolytic Agents

Bovine viral diarrhea virus (BVDV) is a major cattle pathogen responsible for a spectrum of symptoms, including reproductive failure. This study was designed to establish the effects of BVDV infection on estradiol, progesterone and PGF2alpha secretion in the cow. Seven BVDV-free cows were challenged with non-cytopathogenic BVDV (strain Pe 515: 5x10(6) tissue culture infected dose50) so that peak viremia occurred during the initial phase of luteal development in a synchronized estrous cycle. Ovulation was also synchronized in 7 sham-infected animals. Within 2 wk of inoculation, viremia, leukopenia and serum neutralizing antibodies were recorded in all of the BVDV-infected cows but not the sham-infected animals. Between Day 4 and Day 9 post estrus the BVDV-infected cows had significantly (P<0.01) lower plasma estradiol levels than the sham-infected animals. However, the BVDV infection did not alter rectal temperatures, plasma progesterone concentrations or PGF2alpha secretion 17, 18 and 19 d post estrus. These data highlight a potential causal link between BVDV viremia, endocrine dysfunction and poor fertility in the cow.

Topics: Abortion, Veterinary; Animals; Antibodies, Viral; Bovine Virus Diarrhea-Mucosal Disease; Cattle; Diarrhea Viruses, Bovine Viral; Dinoprost; Estradiol; Female; Infertility, Female; Leukocyte Count; Pregnancy; Progesterone

The response to Claviceps purpurea sclerotia administration in pregnant goats was examined in terms of changes in the levels of plasma hormones, the development of pregnancy and kid production. Six treated goats were each given 15 mg milled sclerotia (i.e. 0.105 mg ergotamine) per kilogram live weight twice daily via a stomach tube from days 98 +/- 2 to 107 +/- 2 of gestation. Seven control goats were given water twice daily via a stomach tube during the same period of gestation. The goats were observed for clinical signs of disease, rectal temperatures and live weights were recorded and the condition of the foetuses was monitored by real-time ultrasonography. All control goats delivered live kids. In the treated group two goats aborted 33 and 47 days, respectively, after the start of the administration period, two goats each delivered one normal and one weak kid, and the two remaining goats delivered apparently normal kids. All six treated goats became depressed and had poor appetite during the period of sclerotia administration. Rectal temperatures were significantly increased and live weight changes significantly decreased in the animals in the treated group compared to the control group during the period of C. purpurea administration. Ultrasound examination revealed that foetal deaths occurred between 1 and 42 days before abortion or birth. The appearance of the aborted foetuses varied from fresh to mummified, depending on the number of days between foetal death and expulsion. Microbiological and serological investigations revealed no infectious causes of reproductive failure. The level of 15-ketodihydro-PGF2 alpha was high in goats that aborted following administration of C. purpurea compared with the level in control goats. The oestrone sulphate level did not increase before abortion in the treated goats as in the controls before parturition. There were also changes in these hormones in the four treated goats that delivered live kids, but the changes were considerably smaller. These findings indicate that the endocrine foetal-placental function was disturbed, probably due to injury caused by the C. purpurea toxin ergotamine in the placenta and foetus.

Topics: Abortion, Veterinary; Adrenergic alpha-Agonists; Animals; Body Weight; Claviceps; Dinoprost; Endocrine Glands; Enzyme-Linked Immunosorbent Assay; Ergotamine; Estrone; Female; Fetal Death; Goats; Heart Rate, Fetal; Placenta; Pregnancy; Pregnancy Outcome; Progesterone; Toxoplasma; Toxoplasmosis, Animal

An experiment was performed to determine the effect of elevated prostaglandin F2 alpha (PGF2 alpha) on pregnancy rates of progestogen-treated bred cows in the presence or absence of luteal tissue. Ninety-one beef cows were bred (Day 0) and assigned randomly to receive either 3 mL saline (CON), 15 mg PGF2 alpha, or 15 mg PGF2 alpha + lutectomy (P + L) administered intramuscularly (i.m.) at 8 h intervals on either Days 5-8, 10-13, or 15-18 postbreeding. Lutectomies were performed by transrectal digital pressure before initiation of treatment on Day 5, 10, or 15 for the respective treatment groups. All cows were fed 4 mg/day of melengesterol acetate from two days prior to initiation of treatment until Day 30 postbreeding. Mean concentrations of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were increased in cows administered PGF2 alpha and P + L treatments (398 +/- 23 and 413 +/- 22 pg/ml, respectively; p < 0.01) compared to the CON group (80 +/- 29 pg/ml) regardless of treatment group. Mean concentrations of oxytocin (OT) were increased in cows given PGF2 alpha on Day 10 and 15 (p < or = 0.0001) and tended to be increased on d 5 when compared to CON and P + L treatment groups on Day 5. Pregnancy rates were reduced (p < or = 0.03) in the PGF2 alpha treatment group (23%) and by Day 5-8 compared to CON (72%). Lutectomy tended to improve pregnancy rate in P + L (5-8; 55%) compared to PGF2 alpha (5-8; p = 0.1). Pregnancy rates tended (p < or = 0.07) to increase in the PGF2 alpha treatment groups on Days 5-8 treatment (23%, 50%, and 60% for Days 5-8, 10-13, and 15-18, respectively). The later the treatments were initiated pregnancy rates did not differ between treatments given on Days 10-13 and 15-18. In conclusion, the most susceptible period of embryonic growth to the negative effects of PGF2 alpha was during morula to blastocyst development. Removal of luteal tissue diminishes the negative effects of PGF2 alpha through interruption of the luteal oxytocin-uterine PGF2 alpha feedback loop.

Topics: Abortion, Veterinary; Animals; Cattle; Corpus Luteum; Dinoprost; Drug Administration Schedule; Estradiol; Female; Fetal Death; Oxytocin; Pregnancy; Pregnancy, Animal; Progesterone; Progestins; Time Factors

To determine the role of progesterone in the regulation of endogenous prostaglandin F2 alpha (PGF2 alpha) secretion during cloprostenol-induced abortion and to investigate use of progestins to prevent prostaglandin-associated abortion.. 16 pregnant mares.. To induce abortion, cloprostenol (250 micrograms/d) was administered daily until fetal expulsion or for up to 5 days. In experiment 1, 8 mares, 98 to 153 days' pregnant, received progesterone (300 mg/d) at 24-hour intervals for 5 days, starting 18 hours after the first cloprostenol administration. In experiment 2, 8 mares, 93 to 115 days' pregnant, received altrenogest (44 mg/d) at 24-hour intervals, starting 12 hours after the first cloprostenol administration. Historic control mares, 82 to 102 days' pregnant, received cloprostenol (250 micrograms/d) daily until fetal expulsion.. In control mares, fetal expulsion occurred after 2 to 3 cloprostenol administrations and was associated with significant increases in PGF2 alpha secretion. Abortion did not occur in 5 of 8 progesterone-treated mares and 8 of 8 altrenogest-treated mares, and endogenous PGF2 alpha secretion was inhibited, compared with values in aborting mares.. Circulating progestogen concentrations may have a role in the outcome of pregnancy during prostaglandin-induced abortion. Altered prostaglandin secretion may be a reflection of a direct effect of progesterone or may be caused by the abortion process.. Progestogens might be useful for prevention of abortion in mares in which pregnancy is at risk owing to diseases that are associated with excess prostaglandin secretion.

Topics: Abortion, Veterinary; Animals; Cloprostenol; Dinoprost; Estrogens; Female; Horses; Pregnancy; Pregnancy Outcome; Progesterone; Time Factors

The effect of Toxoplasma gondii inoculation on pregnancy and on endocrine foetal-placental function in pregnant goats was studied. Five susceptible goats were inoculated subcutaneously with T. gondii bradyzoites at 71 +/- 2 days of gestation. Another five goats were used as controls. Plasma was analysed for progesterone, oestrone sulphate and 15-ketodihydro-PGF2 alpha. The condition of the foetuses was monitored by real-time ultrasonography. All inoculated goats aborted or delivered stillborn or weak kids 54-73 days after inoculation. None of the goats showed signs of general disease. In cases of foetal death, the ultrasound examination revealed that death occurred between day 1 and 12 before abortion or birth. The appearance of the foetuses varied from fresh to mummified, depending on the number of days between foetal death and expulsion. All five goats became serologically positive to T. gondii after inoculation. None of the goats used as controls aborted, but one goat delivered one mummified and one weak kid for unknown reasons. In inoculated animals an increase in 15-ketodihydro-PGF2 alpha levels in plasma and a subsequent tendency to a decrease in oestrone sulphate levels were observed from about day 40 after inoculation and until abortion or birth. High levels of 15-ketodihydro-PGF2 alpha were seen after foetal death. High levels of 15-ketodihydro-PGF2 alpha were not always followed by a drop in progesterone levels. The mean level of progesterone was slightly decreased after inoculation and onwards. The pattern of progesterone levels around abortion in the inoculated goats was very similar to the pattern around parturition in the control goats. However, 15-ketodihydro-PGF2 alpha levels were higher both before and after abortion in inoculated goats than in control goats. The level of oestrone sulphate did not increase in the inoculated group before abortion in contrast to the level in goats which delivered healthy kids. The patterns of changes in levels of 15-ketodihydro-PGF2 alpha and oestrone sulphate in inoculated animals indicate that the endocrine foetal-placental function was disturbed in most of the inoculated goats, probably due to the injury caused by the establishment and development of T. gondii infection in the placenta and foetus.

Topics: Abortion, Veterinary; Animals; Dinoprost; Estrogens, Conjugated (USP); Estrone; Female; Goat Diseases; Goats; Maternal-Fetal Exchange; Pregnancy; Pregnancy Complications, Parasitic; Progesterone; Time Factors; Toxoplasma; Toxoplasmosis, Animal

Pregnant cows were fed pine needles (PN, 2 kg.cow-1.d-1) mixed with the diet to determine factors that affect abortion response. In Exp. 1, treatments were used to determine the effects of experimental stress and pelleting of pine needles. Pelleting needles and experimental stress delayed abortion response (P < .01). Stress-induced delay was associated with abnormal patterns of progesterone and cortisol (P < .01). In Exp. 2A and 2B, the role of the corpus luteum (CL) in abortion response to PN consumption was investigated by regressing the CL with prostaglandin F2 alpha. Regression of the CL and PN feeding reduced interval to parturition, but the effect of PN feeding was less when the CL was regressed (PN x CL, P < .01). The progesterone increase in response to experimental stress was decreased by CL regression (P < .01). In Exp. 3, melengestrol acetate (MGA) was fed (0, 2, or 4 mg.cow-1.d-1) in addition to PN. Parturition was blocked more effectively as dose of MGA increased (P = .075), but only parturition was blocked rather than the effects of PN. In Exp. 4, CL regression was blocked by feeding ketoprofen. Ketoprofen delayed response to PN, but the effect was only temporary (P < .01). Our conclusions are that 1) experimental stress delays abortion response to PN by increased concentrations of progesterone, 2) pelleting PN decreases their abortifacient activity, and 3) abortions caused by PN can be blocked by feeding a progestin or a prostaglandin inhibitor, but these compounds do not block the primary abortifacient effects of PN.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Diet; Dinoprost; Female; Hydrocortisone; Ketoprofen; Labor, Obstetric; Luteolysis; Melengestrol Acetate; Plant Leaves; Plant Poisoning; Plants, Toxic; Pregnancy; Progesterone; Progestins; Stress, Physiological; Trees

We measured the concentrations of relaxin (Rlx), progesterone, and estradiol-17 beta in serum samples obtained twice or three times weekly from marmosets during the estrous cycle and pregnancy. The cyclic patterns and concentrations of progesterone and estradiol-17 beta were similar to those reported by previous investigators. Rlx was not detected in individual serum samples ( < 0.62-1.25 ng/ml) obtained from nonpregnant marmosets. However, pooling of luteal serum from all animals permitted assay of much larger volumes of serum (0.4 ml vs. 0.1 ml), and a concentration of about 1 ng/ml was detected. Rlx was first detected in serum in the second or third week of the 21-wk marmoset pregnancy, rose to a peak during Weeks 10-14, and then declined slowly as the time of parturition approached. The pattern of Rlx was unlike that observed during pregnancy in Old World monkeys, chimpanzees, or women, and resembled, instead, that seen in rodents, carnivores, and equids. Progesterone and estradiol-17 beta likewise increased throughout pregnancy, and their patterns were similar to those previously described for marmosets by other investigators. The concentrations of the steroids and Rlx in serum of pregnant marmosets was 10-fold or more higher than those found in Old World monkeys, baboons, chimpanzees, or women. Spontaneous abortions in two of the marmosets were accompanied by precipitous falls in serum levels of progesterone, estradiol-17 beta, and Rlx. Following s.c. injection of the luteolytic agent prostaglandin F2 alpha (PGF2 alpha) into two marmosets at midpregnancy, serum progesterone and Rlx fell to low levels. These animals received a progestin, 17 alpha-ethyl-19-nortesterone, to preclude abortion. Serum progesterone rose again, but serum Rlx remained low for the duration of pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Abortion, Veterinary; Animals; Callithrix; Dinoprost; Estradiol; Female; Male; Pregnancy; Pregnancy, Animal; Progesterone; Relaxin; Time Factors

The objective of this study was to estimate the effect on calving risk of interval from AI date until scheduled date of pregnancy examination. First AI (n = 7105) from 65 dairy herds in the United States and Canada were followed for 294 d to determine whether cows calved. Calving was modeled as a function of the number of days in the interval, herd, season, and breeding at PGF2 alpha-induced estrus by multivariate logistic regression. The main effects of herd and AI following PGF2 alpha-induced estrus were significantly associated with calving rate from first AI. The main effects of interval and season were not significantly associated with calving.

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Dinoprost; Female; Palpation; Pregnancy; Pregnancy Tests; Rectum; Reproducibility of Results; Risk Assessment; Time Factors

For the effects of voltages on health and reproduction, 40 cows in second to fifth lactation were divided into four groups of 10. These included a control group that was not subjected to voltages and three treatment groups that were given either 1, 2, or 4 V at the water bowl. Cows in the treatment groups were exposed during the entire lactation to voltage whenever they drank. Voltages did not sufficiently affect milk yield. General health parameters studied were mastitis, hoof problems, and changes in body weight. Reproductive and calving parameters examined were days to first breeding, days open, services per conception, response to PGF2 alpha, calving intervals, visible abortion, and calves born dead. Voltages did not significantly influence cow health or reproductive performance.

Topics: Abortion, Veterinary; Animals; Body Weight; Cattle; Cattle Diseases; Dinoprost; Electricity; Female; Fetal Death; Foot Diseases; Hoof and Claw; Lactation; Mastitis, Bovine; Pregnancy; Reproduction

The role of prostaglandin F2 alpha (PGF2 alpha) in embryonic loss following induced endotoxemia was studied in mares that were 21 to 44 days pregnant. Thirteen pregnant mares were treated with a nonsteroidal anti-inflammatory drug, flunixin meglumine, to inhibit the synthesis of PGF2 alpha caused by Salmonella typhimurium endotoxin given IV. Flunixin meglumine was administered either before injection of the endotoxin (group 1, -10 min; n = 7), or after endotoxin injection into the mares (group 2, 1 hour, n = 3; group 3, 2 hours, n = 3); 12 pregnant mares (group 4) were given only S typhimurium endotoxin. In group 4, the secretion of PGF2 alpha, as determined by plasma 15-keto-13,14-dihydro-PGF2 alpha concentrations, was biphasic, initially peaking at 30 minutes followed by a second, larger peak approximately 105 minutes after the endotoxin was given IV. When flunixin meglumine was administered at -10 minutes, synthesis of PGF2 alpha was inhibited for several hours, after administration of flunixin meglumine at 1 hour, the second secretory surge of PGF2 alpha was blocked, and administration of the drug at 2 hours did not substantially modify the secretion of PGF2 alpha. Plasma progesterone concentrations were unchanged after endotoxin injections were given in group 1. In group 2, progesterone values decreased less than 2 ng/ml and remained low for several days. In group 3 and group 4, progesterone concentrations decreased to values less than 0.5 ng/ml by 48 hours after endotoxin injections were given.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Abortion, Veterinary; Animals; Clonixin; Dinoprost; Endotoxins; Female; Fetal Death; Horses; Injections, Intravenous; Pregnancy; Progesterone; Salmonella typhimurium; Shock, Septic; Time Factors

Twenty-one, middle to late lactation Holstein cows were assigned to one of three treatments in a completely randomized design to examine physiological changes associated with intramammary or intravenous administration of Escherichia coli endotoxin. Treatments were 1) Hank's balanced salt solution infusion in two contralateral quarters (control), 2) E. coli endotoxin infusion in two contralateral quarters, and 3) intravenous infusion of E. coli endotoxin. Blood was sampled and rectal temperature was measured at 30-min intervals. Endotoxin treatment was at 0900 h and sampling continued until 1700 h. Serum prolactin, cortisol, and 13,14-dihydro-15-keto-prostaglandin F2 alpha were measured. A pyretic response was observed in intravenous and intramammary treatment groups after endotoxin treatment. Response peak was higher (41.1 vs. 40.3 degrees C) and occurred later (6 vs. 4.5 h posttreatment) in the intramammary than the intravenous treatment group. Significant prolactin peaks were observed also in intravenous and intramammary endotoxin treatment groups. Prolactin peaked higher (288 vs. 112 ng/ml) and occurred sooner (1 vs. 4 h posttreatment) in the intravenous than in the intramammary treatment group. Cortisol followed a trend similar to prolactin. Cortisol peaked higher (100 vs. 82 ng/ml) and sooner (2.5 vs. 4.5 h posttreatment) in the intravenous than in the intramammary treatment group. Concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha increased rapidly posttreatment in the intravenous group only.

Topics: Abortion, Veterinary; Animals; Body Temperature; Cattle; Dinoprost; Endotoxins; Female; Hydrocortisone; Injections, Intravenous; Lactation; Mastitis, Bovine; Pregnancy; Prolactin; Random Allocation

The effects of Escherichia coli endotoxin infusions (1.0 or 2.5 micrograms kg-1 over 6 h) on pregnancy were investigated in cows in the first, second and third trimester of gestation. Endotoxin increased the plasma levels of prostaglandins (PGs), thromboxane B2 and cortisol, and decreased progesterone. The severity of the clinical signs and the magnitude of the increases in plasma PGs, thromboxane B2 and cortisol tended to depend on the dose of endotoxin, but were independent of the gestation period. There was hyperglycemia followed by hypoglycemia and lactic acidemia. Hyperglycemia and lactic acidemia were significant only at the high dose of endotoxin. Endotoxin infusion at both doses caused a preferential mobilization of oleic acid from adipose tissue, and also had some effects on the mobilization of palmitic and stearic acids during the post-infusion period. The cows in the first trimester of gestation were more sensitive to the abortifacient effect of endotoxin than cows in the second and third trimester of gestation. The results of this study indicate that the mechanism of endotoxin-induced abortion in cows initially involves a prolonged release of PGF2 alpha and its subsequent stimulant effect on uterine smooth muscle contraction and luteolytic effect leading to a gradual decline in the plasma levels of progesterone. It was concluded that pregnancy terminates in the absence of an adequate level of progesterone, especially during the first trimester of gestation, when progesterone of extraluteal origin is not yet available, coupled with the PGF2 alpha-induced propulsive contraction of the uterus. In addition, the metabolic and circulatory failures in severe cases of endotoxemia, especially at the high dose of endotoxin, resulting either directly or indirectly via the release of various autacoids, catecholamines and cortisol, may also contribute to the termination of pregnancy at any stage of gestation.

Topics: Abortion, Veterinary; Animals; Blood Glucose; Body Temperature; Cattle; Cattle Diseases; Dinoprost; Endotoxins; Escherichia coli; Fatty Acids; Female; Hydrocortisone; Lactates; Lactic Acid; Pregnancy; Pregnancy, Animal; Progesterone; Prostaglandins; Thromboxane B2; Uterine Contraction

Ultrasonography was performed to determine the fate of the conceptus and the corpus luteum after induced embryonic loss in heifers. When embryonic loss was induced by administration of prostaglandin F2 alpha (25 mg, IM) on day 28 (n = 10) or day 42 (n = 10), embryonic death occurred 2.3 +/- 0.2 (mean +/- SEM) and 2.6 +/- 0.2 days, respectively, after treatment, and subsequent ovulation occurred 2.4 +/- 0.3 and 2.7 +/- 0.2 days, respectively, after embryonic death. Administration of a mitotic inhibitor (1 mg of colchicine, intrauterine; n = 4) on day 42 resulted in embryonic death in 1.2 +/- 0.2 days and ovulation in 20.8 +/- 3.1 days after embryonic death. Rupture of the amnion on day 42 (n = 3) resulted in immediate death of the embryo and ovulation in 35 +/- 3.5 days. In prostaglandin-treated heifers, area of the corpus luteum decreased (P less than 0.01) between days -2 and -1, relative to day of embryonic death. Volume of uterine contents remained approximately constant for 2 or 3 days after treatment, then decreased greater than 75% between examinations on consecutive days. Embryonic death apparently resulted from luteolysis and was characterized by rapid loss of the conceptus with minimal conceptus degeneration; an intact conceptus was recovered from the vagina of 3 heifers treated on day 42. In heifers treated with colchicine or in which the amnion was ruptured, embryonic death was associated with maintenance of the corpus luteum and prolonged retention of the conceptus, which underwent extensive degeneration.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Colchicine; Corpus Luteum; Dinoprost; Female; Fetal Death; Pregnancy; Ultrasonography

Serum and urinary estrone sulfate concentrations were determined in 7 pregnant mares before and after prostaglandin-induced abortion (n = 4) or surgical removal of the fetus (n = 3) to determine the source of estrogen during early pregnancy (gestation days [GD] 44 to 89). Estrone sulfate concentrations also were determined in serum samples (stored frozen for 2 years) from 3 mares that had been ovariectomized between GD 51 and 58. Estrone sulfate concentrations decreased in serum and urine after expulsion or removal of the fetus (urinary patterns were more definitive than were patterns for serum), whereas a transient decrease in serum estrone sulfate concentration was observed after ovariectomy. Seemingly, products of conception are the major source of estrone sulfate during early pregnancy, although there appears to be some ovarian contribution. Serum or urinary estrone sulfate measurements provide a simple and accurate test for fetal viability after GD 44 in the mare.

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Dinoprost; Estrogens, Conjugated (USP); Estrone; Female; Fetal Death; Horse Diseases; Horses; Pregnancy; Prostaglandins F

Plasma luteinizing hormone (LH) and progesterone concentrations were compared in does experiencing short-duration estrous cycles and in does with estrous cycles of normal duration. The short-duration estrous cycles were observed immediately after induction of abortion in pregnant does by use of prostaglandin (PG) F2 alpha. Intramuscular administration of 5 mg of PGF2 alpha was accomplished in 8 does that were 52 to 63 days into gestation and in 9 cycling does at 7 to 10 days after estrus. In both groups, the mean plasma concentration of progesterone decreased from a luteal phase concentration immediately before to less than 1 ng/ml by 24 hours after PGF2 alpha administration. Of the 8 does that aborted, 6 experienced short-duration estrous cycles, and 4 of these 6 had an LH surge during the time of blood sample collection. The mean time from PGF2 alpha administration to the LH surge was significantly (P less than 0.05) longer in does with short-duration estrous cycles (71 hours) than that in does with estrous cycles of normal duration (58 hours). The mean area under the LH concentration curve was significantly (P less than 0.005) less for does with short-duration estrous cycles. Short-duration estrous cycles were associated with delayed preovulatory LH surges of reduced magnitude.

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Diestrus; Dinoprost; Estrus; Female; Goats; Luteinizing Hormone; Pregnancy; Progesterone; Prostaglandins F

Fourteen unvaccinated and seronegative ewes were experimentally infected with bovine virus diarrhoea virus around day 60 of pregnancy. Two other groups of pregnant ewes served as control animals. The animals were followed with ultrasound scanning to study the status of the fetus and with frequent blood sampling for analysis of progesterone and 15-keto-13,14-dihydro-PGF2 alpha, two hormones that could reflect the propagation of the infection. The unvaccinated ewes responded to the infection with abortion, resorption of the fetus, mummification or no changes at all. The endocrinological changes reflected in a most adequate way the pathological changes in the uterus. Detailed endocrinological studies can contribute to the understanding of the pathogenesis of some infectious diseases that affect reproduction.

Topics: Abortion, Veterinary; Animals; Bovine Virus Diarrhea-Mucosal Disease; Cattle; Cattle Diseases; Dinoprost; Female; Fetal Resorption; Fetal Viability; Pregnancy; Pregnancy Complications, Infectious; Progesterone; Prostaglandins F; Sheep; Sheep Diseases; Ultrasonography

Gilts were treated during midgestation with prostaglandin (PG) F to study the efficacy of different treatment regimens on induction of abortion and to determine the adverse consequences of PGF-induced abortion in swine. In study 1, pregnant purebred Duroc gilts (60 to 90 days of gestation) were given (IM) 500 micrograms of cloprostenol (n = 12), 20 mg of dinoprost tromethamine (n = 11), or 10 mg of dinoprost tromethamine repeated 12 hours later by an additional 10 mg of dinoprost tromethamine (n = 11). The percentage of gilts that aborted and percentage of aborted gilts that returned to estrus for each treatment group were as follows: cloprostenol, 91.7% and 100%, respectively; 20 mg of dinoprost tromethamine, 36.4% and 25.0%, respectively; and 10 + 10 mg of dinoprost tromethamine, 100% and 90.9%, respectively. Treatment with cloprostenol and with 10 + 10 mg of dinoprost tromethamine caused more gilts to abort (P less than 0.01) than did treatment with 20 mg of dinoprost tromethamine. Gilts that did not abort were given a second treatment with 10 + 10 mg of dinoprost tromethamine. When the abortions by gilts initially treated with 500 micrograms of cloprostenol or 10 + 10 mg of dinoprost tromethamine were combined with those re-treated with 10 + 10 mg of dinoprost tromethamine, 32 of 33 (97.0%) gilts aborted, and 30 of the 32 (93.8%) aborted gilts returned to estrus.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Abortifacient Agents; Abortifacient Agents, Nonsteroidal; Abortion, Induced; Abortion, Veterinary; Animals; Cloprostenol; Dinoprost; Estradiol; Estrus; Female; Luteinizing Hormone; Pregnancy; Pregnancy, Animal; Progesterone; Prostaglandins F, Synthetic; Swine; Swine Diseases

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Dinoprost; Estrus; Female; Horses; Pregnancy; Pregnancy, Animal; Progesterone; Prostaglandins F

Data were obtained in a large Florida herd of about 1800 Holstein cows. All cows were inseminated by the herdsman who did the pregnancy checks and who also administered drugs. The herdsman injected 103 cows with prostaglandin F2 alpha during the time this herd was under continuous observation by the authors who were conducting an unrelated research project. These cows consisted of 86 open (never bred) cows which had no estrus observed during the first 70 days postpartum, or no second estrus observed within 30 days after a previous estrus, and 17 cows previously inseminated. Two-thirds (57) of the 86 open cows were in estrus within 4 days. The 17 previously inseminated cows appeared to be pregnant, based upon progesterone profiles, when these were inadvertently given prostaglandin F2 alpha by the herdsman. Progesterone declined in all cows and they were in estrus in 7 +/- 4 days (mean +/- standard error). This result of presumed abortion reflects the luteolytic effectiveness of the drug and the importance of instructing any laymen users to follow necessary precautions to avoid undesirable effects.

Topics: Abortion, Veterinary; Animals; Cattle; Dinoprost; Estrus; Female; Insemination, Artificial; Milk; Pregnancy; Progesterone; Prostaglandins F

Feeding 300 or 400 g of dried spotted locoweed, Astragalus lentiginosus per day to 11 pregnant Columbia ewes from the 20th to the 50th days of their gestations resulted in dead and edematous fetuses. Aspartate aminotransferase values were increased, whereas serum progesterone values were significantly diminished (P less than 0.05) in a dose-dependent manner by locoweed ingestion. Cotyledonary 6-keto-prostaglandin (PG)F1 alpha (400 g/day only) and PGF2 alpha (300 and 400 g/day) values were significantly increased (P less than 0.05), whereas PGE values were not affected by the treatment. Alterations in PG values in these sheep may be a mechanism for altering corpus luteum function and inducing fetal death, which would ultimately result in abortion.

Topics: 6-Ketoprostaglandin F1 alpha; Abortion, Veterinary; Animals; Dinoprost; Female; Placenta; Plant Poisoning; Plants, Toxic; Pregnancy; Progesterone; Prostaglandins; Prostaglandins E; Prostaglandins F; Radioimmunoassay; Sheep; Sheep Diseases; Tritium

Within a group of 130 mares which, in the event, carried twin pregnancies, 29 (22.3 per cent) produced their twins following diagnosis of a single palpable follicle at service and a single pregnancy 42 days later. The whole group of 130 twin-pregnant mares gave birth to only 17 live foals (13 per cent). Breeding results for the following season were available for 102 of these mares, when 38 (37 per cent) produced live foals. Thus over the two seasons an average 23 per cent of this group produced live foals. In a second group, comprising 70 mares, twin pregnancy had been diagnosed in all of them by rectal palpation. Five methods of treatment were then applied to five subgroups of mares and 20 (28 per cent) of the 70 mares produced live foals that season. Breeding results for the following season were available for 53 of these mares; 33 (61 per cent) then produced live foals. Thus over the two seasons an average 46 per cent of the treated group produced live foals. The administration of a prostaglandin analogue at less than 35 days of gestation was outstandingly successful as a method of treatment.

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Dinoprost; Female; Horse Diseases; Horses; Meclofenamic Acid; Pregnancy; Pregnancy Tests; Pregnancy, Animal; Prostaglandins F; Reproduction; Sodium Chloride; Twins

Topics: Abortifacient Agents; Abortion, Induced; Abortion, Veterinary; Animals; Breeding; Cattle; Dinoprost; Estrus; Estrus Synchronization; Female; Fertility; Pregnancy; Prostaglandins F

Pregnant cows at 4- to 5-months' of gestation were exposed to Sarcocystis cruzi or Campylobacter fetus. Plasma prostaglandin F (PGF) and 13,14-dihydro-15-ketoprostaglandin metabolite (PGM) concentrations were determined at intervals from before exposure until abortion or parturition. The plasma PGF concentration of pregnant infected cattle remained at 0.02 +/- 0.04 ng/ml until 24 to 48 hours before abortion or parturition when it increased 5-fold to 0.11 +/- 0.12 ng/ml. The plasma PGM concentration of these cattle remained at 0.10 +/- 0.07 ng/ml until 24 to 48 hours before abortion or parturition when it increased over 10-fold to 1.36 +/- 0.60 ng/ml. This change in PGF and PGM was similar to that of cattle exposed to each of the infective agents and to that of normal cows at parturition. Thus, changes in PGF and PGM concentrations in bovine plasma cannot be used as a diagnostic tool to determine fetal distress or fetal death for these infections.

Topics: Abortion, Veterinary; Animals; Campylobacter Infections; Cattle; Cattle Diseases; Dinoprost; Female; Labor, Obstetric; Pregnancy; Pregnancy Complications, Infectious; Prostaglandins F; Sarcocystosis

Topics: Abortion, Induced; Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Cloprostenol; Dexamethasone; Dinoprost; Estrone; Female; Labor, Induced; Labor, Obstetric; Obstetric Labor, Premature; Pregnancy; Progesterone; Prostaglandins F