oxytetracycline--anhydrous and Abortion--Veterinary

The effects of long acting oxytetracycline in controlling outbreaks of enzootic abortion of ewes were studied over three consecutive years in 13 different commercial flocks. When used in the face of an outbreak the compound produced a statistically significant reduction in abortion in treated ewes when compared to untreated controls. There was, however, only a marginal difference in the overall abortion rate between treated and untreated groups of ewes in known infected flocks, where the drug was used in anticipation of an abortion storm, mainly because the abortion rate was too low in the control group. It is suggested that oxytetracycline therapy should only be used in an effort to control an actual abortion outbreak on the understanding that the treatment will not eradicate infection from the flock.

Topics: Abortion, Veterinary; Animals; Chlamydia Infections; Clinical Trials as Topic; Delayed-Action Preparations; Disease Outbreaks; Female; Oxytetracycline; Pregnancy; Sheep; Sheep Diseases

The aim of this research was to evaluate the efficacy of oxytetracycline treatment following an outbreak of Q fever in a sheep flock when gestation is too advanced for vaccination to be used. In such cases, immediate application of antibiotics is needed and vaccination postponed until the next breeding season. Seventy-five per cent of ewes from a dairy sheep flock affected by Q fever were treated with oxytetracycline at approximately days 100 and 120 of gestation, with the remaining 25% of the animals kept as untreated controls. Vaginal swabs, faeces and milk samples from 81 ewes (57 treated, 24 untreated) were analysed by PCR within 30 days of lambing and revealed a high percentage of Coxiella burnetii shedders. No significant differences were found between groups in either the percentage of shedders or in the mean amount of bacteria shed. In the following season 75% of the ewes and 50% of the replacement ewe lambs were vaccinated with a phase I vaccine prior to artificial insemination. Both vaccinated and control groups were homogeneously composed of ewes treated and untreated with antibiotics in the previous season. The number of shedders and the bacterial excretion load decreased significantly compared to the previous season but no statistically significant differences were found between vaccinated and control groups. In addition, no significant effect derived from the application of oxytetracycline in the previous season was observed. Vaccination was repeated for the following two seasons, and the percentage of animal shedders was reduced to minimal levels highlighting the importance of vaccination over the longer term.

Topics: Abortion, Veterinary; Animals; Anti-Bacterial Agents; Bacterial Shedding; Colony Count, Microbial; Coxiella burnetii; Enzyme-Linked Immunosorbent Assay; Feces; Female; Milk; Oxytetracycline; Q Fever; Real-Time Polymerase Chain Reaction; Seasons; Sheep; Sheep Diseases; Vaccination; Vagina

In October 1998, two abortions associated with Coxiella burnetii occurred in a group of 34 pregnant ewes in the sheep flock belonging to INRA Tours-Nouzilly. The flock was kept in groups of approximately 40 ewes, which were housed together in the same accommodation. The prevalence of C burnetii infection in the groups was investigated by using ELISA and PCR tests, which revealed a high prevalence of C burnetii. The ewes were treated with oxytetracycline to reduce the shedding of C burnetii and to prevent further abortions. Nevertheless, five abortions attributed to C burnetii occurred in January and March 1999 in three groups of ewes, and 24 of the ewes still shed the bacteria into their vaginal tracts. In addition, a serological study was carried out during the first year of life of the female lambs born in 1999 and 2000; 12 per cent of 113 lambs born in 1999 were seropositive for C burnetii by ELISA, and half of the ELISA-positive lambs were born either to serologically positive ewes or to dams that excreted the pathogen into their vaginal tracts. However, all the 150 lambs born in 2000 were ELISA-negative, suggesting that the preventive measures undertaken had suppressed both the abortions and the shedding of C burnetii, and reduced the transmission of the agent.

Topics: Abortion, Veterinary; Animals; Animals, Newborn; Anti-Bacterial Agents; Coxiella burnetii; Enzyme-Linked Immunosorbent Assay; Feces; Female; Infectious Disease Transmission, Vertical; Oxytetracycline; Polymerase Chain Reaction; Pregnancy; Q Fever; Seroepidemiologic Studies; Sheep; Sheep Diseases; Vagina

Toxoplasma gondii tachyzoites were seen in the placenta of a late-term aborted Greenland muskox (Ovibos moschatus wardi) fetus in a captive herd at the San Francisco Zoo. The organism stained with anti-T. gondii polyclonal rabbit serum but not with anti-Neospora caninum serum. The dam had a Toxoplasma titer of > or =1:3,200 at the time of abortion and in each of the previous 3 yr (modified agglutination test). The muskox is a new host record for T. gondii.

Topics: Abortion, Veterinary; Agglutination Tests; Animals; Anti-Infective Agents, Local; Antibodies, Protozoan; Birth Weight; Female; Histocytochemistry; Oxytetracycline; Placenta; Povidone-Iodine; Pregnancy; Ruminants; Tetracyclines; Toxoplasma; Toxoplasmosis, Animal

Three therapeutic regimens were evaluated in 121 cows naturally infected with Brucella melitensis or Brucella abortus, using a combination of long-acting oxytetracycline (LA-OTC), streptomycin (ST) and OTC-intramammary infusion (IMI). Cessation of shedding of Brucella in udder secretions and absence of Brucella in selected tissues were considered criteria for successful treatment. Regimen A (tested on 35 cows) consisted of LA-OTC 25 mg/kg administered intramuscularly (i.m.) every 3 days for 42 days, ST 25 mg/kg i.m. daily for 8 days, and OTC-IMI 20 ml/teat daily for 4 days. Regimen B (tested on 53 cows) was similar to regimen A, except that ST was administered every 2 days for 16 days and OTC-IMI every 2 days for 8 days. Both regimens were equally effective in eliminating Brucella organisms from all cows involved in the tests and no relapses were recorded. However, regimen C, which was similar to regimen A, except that ST was administered every 3 days for 24 days and OTC-IMI every 3 days for 12 days, resulted in the elimination of Brucella organisms from only 30 (91%) of 33 cows. Before commencement of the therapeutic regimens, B. melitensis biovar 1 or 2 had been repeatedly isolated from udder secretions of 103 cows and B. abortus biovar 1 from mammary secretions of 18 cows.

Topics: Abortion, Veterinary; Agglutination Tests; Animals; Antibodies, Bacterial; Brucella abortus; Brucella melitensis; Brucellosis, Bovine; Cattle; Costs and Cost Analysis; Delayed-Action Preparations; Female; Infusions, Parenteral; Injections, Intramuscular; Mammary Glands, Animal; Oxytetracycline; Pregnancy; Pregnancy Complications, Infectious; Reproduction; Streptomycin

Six treatment regimens using oxytetracycline (OTC) combined with streptomycin (ST) were evaluated for eliminating Brucella melitensis from 480 naturally-infected sheep and goats. Cessation of shedding Brucella from udder secretions and absence of Brucella in selected tissues at autopsy were considered criteria for successful treatment. Four regimens were equally effective in eliminating Brucella in the treated groups of sheep and goats regardless of the source of antibiotics used. These were regimen A (OTC 20 mg/kg intravenously daily for 6 weeks, combined with ST 20 mg/kg intramuscularly [i.m.] daily for 3 weeks), regimen B (long-acting [LA]-OTC 20 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks), regimens D and E (LA-OTC 28 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks). However, regimen C (LA-OTC 20 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks) eliminated Brucella in only 75 of 80 (94%) sheep and goats. Regimen F (LA-OTC 25 mg/kg i.m. every 2 days for 4 weeks, combined with ST 20 mg/kg i.m. every 2 days for 2 weeks) was the most practical, effective and least expensive regimen for eliminating Brucella in the 80 treated sheep and goats. Brucella melitensis biovar 2 was repeatedly isolated from the mammary secretions of all sheep and goats before treatment. It was also isolated repeatedly from the udder secretions of all non-treated control animals and from selected tissue specimens collected from the controls at necropsy.

Topics: Abortion, Veterinary; Animals; Brucella melitensis; Brucellosis; Costs and Cost Analysis; Drug Therapy, Combination; Female; Goat Diseases; Goats; Mammary Glands, Animal; Oxytetracycline; Pregnancy; Random Allocation; Reproduction; Sheep; Sheep Diseases; Streptomycin; Treatment Outcome

Topics: Abortion, Septic; Abortion, Veterinary; Animals; Chlamydophila psittaci; Female; Oxytetracycline; Pregnancy; Psittacosis; Sheep; Sheep Diseases; Vaccination

The efficacy of oxytetracycline (OTC) alone or combined with streptomycin in the treatment of 118 Najdi ewes believed to have been naturally infected with Brucella melitensis, was evaluated by culture of selected tissues and organs at slaughter. Groups of sheep were given 250, 500 or 1,000 mg of OTC intraperitoneally (i/p) daily for six weeks and in the respective groups at necropsy 52, 69 and 100% of sheep were found to be Brucella-free. Treatment with 250 mg OTC (daily for six weeks i/p) combined with 1,000 mg streptomycin (daily for three weeks intramuscularly) increased the percentage of Brucella-free sheep to 82%. When a group of sheep were each inoculated i/p with 1,000 mg of long-acting OTC every three days over a period of six weeks, 75% of them were Brucella-free at necropsy. B. melitensis was isolated from all (24) non-treated (control) sheep. The results showed that long-term treatment with a high dose of OTC alone had succeeded in eliminating B. melitensis from a group of 16 naturally infected sheep.

Topics: Abortion, Veterinary; Animals; Brucellosis; Drug Therapy, Combination; Female; Infertility, Female; Oxytetracycline; Pregnancy; Pregnancy Complications, Infectious; Random Allocation; Sheep; Sheep Diseases; Streptomycin

One hundred and ninety-six housed pregnant ewes were fed poor quality silage for two days. Ewes are reluctant to eat the silage and within 48 hours they became dull and developed diarrhoea and lameness. Despite treatment with antibiotics and calcium borogluconate 19 ewes died, more than 60 developed vaginal discharges and at lambing 94 ewes were barren. Six developed nervous signs and two of these died, one with lesions typical of listeric encephalitis. Post mortem lesions and the isolation of Listeria monocytogenes type 1/2 from lung, liver, spleen and kidney are described. L monocytogenes was also isolated from blood samples from live ewes. The estimated gross financial loss to the farmer was 5130 pounds or, for the flock, 26 pounds per ewe.

Topics: Abortion, Veterinary; Animal Feed; Animals; Encephalitis; Female; Listeria monocytogenes; Listeriosis; Oxytetracycline; Pregnancy; Sepsis; Sheep; Sheep Diseases

During 1978-79 there was an outbreak of abortion in a large sheep flock during which approximately 10 per cent of the breeding ewes aborted. Both Toxoplasma gondii and Chlamydia ovis (the agent of enzootic abortion of ewes) were considered to be involved. In the year following this outbreak (1979-80), 156 ewes (11.4 per cent) aborted and the majority of cases were diagnosed as enzootic abortion: only one case showed gross pathology typical of toxoplasmosis. Serology carried out on sera collected from ewes at the time of abortion and at two post abortion samplings demonstrated that large numbers of animals had high titres against enzootic abortion of ewes while the prevalence of sheep with titres against toxoplasmosis was relatively low. Following the introduction of control measures to reduce the spread of enzootic abortion of ewes, the abortion rate in 1980-81 fell to 2.2 per cent. A small-scale trial was carried out to investigate the prophylactic effect of long acting oxytetracycline against enzootic abortion of ewes when given to pregnant sheep three weeks before lambing. Results indicated that treatment reduced the number of abortions in comparison with untreated controls.

Topics: Abortion, Veterinary; Animals; Chlamydia Infections; Disease Outbreaks; Female; Oxytetracycline; Pregnancy; Scotland; Sheep; Sheep Diseases; Toxoplasmosis, Animal

Topics: Abortion, Veterinary; Animals; Chlamydia Infections; Delayed-Action Preparations; Female; Oxytetracycline; Pregnancy; Sheep; Sheep Diseases

The treatment of ovine abortifacient chlamydias with Terramycin/LA 200 was examined in three successive experiments in which ewes were inoculated intradermally with 6 x 10(5) PFU chlamydia at 80 days of pregnancy. The efficacy of the treatment was estimated by comparing a control group with a treated group for number of live lambs, number of abnormal lambings, length of pregnancy, average weight of lambs at birth and genital excretion of chlamydia at lambing. Sixty to eighty per cent of the ewes in the control group aborted. Under these conditions a single treatment of 20 mg/kg of Terramycin/LA at day 105 of pregnancy, i.e. four weeks after the inoculation, is not effective. On the other hand, a combination of injections, one three weeks and one five weeks after the inoculation, result in longer pregnancies on average, fewer abortions and more liveborn lambs. However, the treatment does not modify either the weight of liveborn lambs or the vaginal excretion of chlamydia at lambing. The adaptation of this treatment to practical conditions and its interest are discussed.

Topics: Abortion, Veterinary; Animals; Chlamydia Infections; Female; Injections, Intramuscular; Oxytetracycline; Pregnancy; Sheep; Sheep Diseases

Forty-five brucella infected cows were studied 15 to 30 days following abortion. Eighteen cows were slaughtered and autopsied for examination of Brucella in the organs and lymph nodes. The remaining 27 cows were treated during two and one-half months and then slaughtered after undergoing a treatment with 0, 1, 2 or 3 intraperitoneal injections of oxytetracycline dissolved in 100 ml of physiological saline. The treatment modified only slightly the natural evolution of antibody titers. The levels of infection were similar for all cows which received no treatment. Cows treated with oxytetracycline had less severe infection than the non treated animals and four were infection-free at slaughter. The level of infection of treated cows was independant of the treatment regime. The advantages of treating non pregnant cows to reduce the level of infection and risk of abortion were discussed.

Topics: Abortion, Veterinary; Animals; Brucella abortus; Brucellosis, Bovine; Cattle; Female; Milk; Oxytetracycline; Pregnancy

Topics: Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Clioquinol; Female; Furazolidone; Injections; Leukorrhea; Oxytetracycline; Pregnancy; Uterine Diseases; Uterus