pyrantel-tartrate and Ascariasis

Fifty-four crossbred, 4-week-old pigs divided into nine equal groups were used to test whether multiple inoculations with high numbers of A. suum eggs with or without anthelmintic would result in patent infections. All pigs exposed to multiple prechallenge inoculations of 500, 1000, 2000, 5000, 10,000 and 20,000 and challenged orally 2 weeks later with 10,000 eggs harboured adult worms. When prechallenge infections were removed by pyrantel tartrate treatment the animals were more susceptible to challenge than controls not previously exposed to infections. The same drug used from 2 days before until 10 days after the last prechallenge infection eliminated that effect. Pigs subjected to the same multiple egg dosing regimen but given feed containing fenbendazole immediately before, during and for 10 days after multiple dosing developed significantly more adult intestinal worms after challenge than any other group. These worms were, however, significantly shorter than those that developed in any group of pigs. Adult worms from all these groups produced eggs that after embryonation were infective to mice.

Topics: Animals; Ascariasis; Ascaris suum; Disease Susceptibility; Female; Fenbendazole; Pyrantel Tartrate; Random Allocation; Swine; Swine Diseases

Crossbred young pigs were used to test whether abbreviated infections with eggs of Ascaris suum can stimulate the acquisition of resistance to challenge. Weanling pigs from an Ascaris-free colony were kept free of A. suum until they were divided into groups at the age of 7-8 weeks. The experimental animals received pyrantel tartrate during the period when they were being exposed to increasing numbers of infective A. suum eggs and challenged 10 days after the last infective dose. Liver milk-spot counts and larval recoveries from the lungs indicated that the strongest resistance was acquired by the animals that received the drug continuously for 6 weeks while being exposed to six weekly infective egg doses. The data do not suggest any drug-related suppression of the resistance response to A. suum infection.

Topics: Animals; Ascariasis; Ascaris; Larva; Pyrantel; Pyrantel Tartrate; Swine; Swine Diseases

Cross-bred 3- and 8-wk-old pigs were used to test whether drug-abbreviated infections with Ascaris suum can stimulate acquired resistance to challenge. During the immunization period, both age groups of animals were infected with increasing numbers of A. suum eggs (500, 1,000, 2,000, 5,000, 10,000, and 20,000) at 7-day intervals while the pigs were receiving pyrantel tartrate in the feed. Two days after the last infective dose, animals were placed on unmedicated feed for 8 days and then challenged with 10,000 eggs. All pigs were killed 7 days after challenge, and milk spots on the livers and larvae recovered from the lungs were counted. Larval recoveries from lungs of the immunized animals were significantly smaller than those from the unimmunized animals in both age groups, suggesting that the pigs were capable of acquiring strong resistance to parasitic infections. In immunized animals, challenge infection did not contribute significantly to milk spot formation. The number of milk spots was significantly greater in the older animals, indicating that milk spot formation may be age related.

Topics: Age Factors; Animals; Ascariasis; Ascaris; Immunization; Intestines; Larva; Liver; Lung; Pyrantel Tartrate; Swine; Swine Diseases

An experiment was conducted with 96 weanling pigs (avg initial wt 18.5 kg) divided into six treatment with two replicates of eight pigs each. Pigs in Treatments 1, 2 and 3 were penned in outside pens with dirt lots that previously were contaminated with A. suum ova to induce a natural ascaris infection. Pigs in Treatments 4, 5 and 6 were penned in an open-front building with solid concrete floors and were experimentally infected with 2,000 embryonated A. suum. ova on d 1, 15 and 29 of the experiment. Pigs in Treatments 1 and 4 were medicated with fenbendazole (FBZ, 3 mg/[kg BW.d]) for three consecutive days during three consecutive time periods. Pigs in Treatments 2 and 5 were medicated with pyrantel tartrate (PT, 106 mg/kg feed) for 28 d. Pigs in Treatments 3 and 6 served as infected, unmedicated controls. All pigs were challenged with 100 A. suum eggs 7 d after termination of the final FBZ treatment. All pigs were killed 66 d after challenge and worms were recovered. Fenbendazole treatment resulted in greater (P less than .07) average daily gain than PT treatment in pigs penned outside. Among inside pigs, FBZ treatment resulted in better (P less than .02) feed utilization than in controls. The FBZ and PT treatments reduced (P less than .03) the total number of A. suum, the length and weight of female ascarids and the length of male ascarids compared with controls. A natural continual infection with A. suum was less effective than experimental infection in inducing protective immunity in pigs.

Topics: Animals; Ascariasis; Benzimidazoles; Female; Fenbendazole; Housing, Animal; Liver; Lung; Male; Organ Size; Parasite Egg Count; Pyrantel; Pyrantel Tartrate; Random Allocation; Swine; Swine Diseases; Weight Gain

The use of pyrantel tartrate (106 mg/kg of feed) as a continuous feed medication was evaluated in 848 finishing hogs for efficacy in preventing Ascaris suum infections, and in reducing liver fibrosis and liver condemnation at slaughter, associated with A suum infections. Liver condemnations due to Ascaris damage were reduced 100% in all pigs given pyrantel, when compared with condemnation in non-medicated controls. None of the livers from any of the medicated animals was condemned, whereas livers from 101 (21%) of 479 nonmedicated pigs were condemned due to extensive hepatic scarring. Pyrantel medication administered for 62, 45, or 28 to 31 days resulted in reductions of total number of livers lesions at slaughter by 93.4%, 80.5%, and 68.6%, respectively. In nearly all cases, hepatic lesions remaining at slaughter of pigs given pyrantel in the feed were less distinct than were lesions found on livers from nonmedicated pigs.

Topics: Animals; Ascariasis; Food Inspection; Liver; Meat; Pyrantel; Pyrantel Tartrate; Swine; Swine Diseases

Oral inoculation of mice with 340 embryonated eggs of the nematode, Baylisascaris procyonis, proved uniformly fatal as early as 13 days after inoculation and as late as 48 days. Mice given either 0.5% or 0.25% of pyrantel tartrate in dry feed were protected from cerebral migrations of the worm for 55 days. Treatment with pyrantel pamoate in the feed at the concentration of 0.2% given 7 days before inoculation and 5 days after inoculation also protected mice from migrations throughout the 55-day experiment. Embryonated eggs stored in 0.5% formalin in a 4-C refrigerator for 9 years have proved fatal to mice given doses of 340 eggs each.

Topics: Animals; Ascariasis; Ascaris; Female; Locomotion; Mice; Pyrantel; Pyrantel Pamoate; Pyrantel Tartrate; Raccoons; Rodent Diseases

Oral administration of solutions of pyrantel tartrate at 50, 75, 100 and 125 mg/kg body weight gave 43.9, 82.1, 92.8 and 99.1 per cent efficacy respecively. None of the chicks given 100 and 125 mg/kg body weight showed any sign of toxicity.

Topics: Animals; Ascariasis; Ascaridiasis; Chickens; Poultry Diseases; Pyrantel; Pyrantel Tartrate

At a dose of 15 mg/kg body weight, pyrantel tartrate was 18-51, 99-63, 100 and 100 per cent effective in chickens treated at 10, 20, 30 and 40 days respectively after infection with Ascaridia galli. Similarly, 25 mg/kg was 14-44, 100, 100 and 99-63 per cent effective.

Topics: Administration, Oral; Animals; Ascariasis; Ascaridiasis; Chickens; Poultry Diseases; Pyrantel; Pyrantel Tartrate