gastrointestinal nematodes, calves (exper.), efficacy of ivermectin given subcutaneously or given orally as drench or paste

Sarcoptes scabiei var. suis, ivermectin, single treatment of infected sows before farrowing eliminated scabies from sows and prevented its transmission to their offspring, offspring remained uninfected throughout study regardless of whether they were treated with ivermectin at weaning, infection (epizootic) in growing pigs could be controlled by single treatment of all in-contact pigs but routine treatment of all pigs at weaning does not seem justified

Ostertagia ostertagi, beef cattle, acquisition of inhibited larvae during winter and spring, efficacy of ivermectin against inhibited early 4th-stage larvae of O. ostertagi and other nematodes of abomasum and intestinal tract: Louisiana

Strongyloides ransomi, pigs, kinetics of expulsion of primary worm populations from small intestine, challenge exposure after either 1 or 2 inoculations of L3, migration route of L3 from site of inoculation to intestine, effect of ivermectin on arrested L3 in subventral fat tissue, effect of acquired immunity on migration and survival of L3

Draschia, Habronema, horses, cutaneous infection (summer sores), efficacy of ivermectin

Ascaris suum, Trichuris suis, naturally infected 10-week-old female pigs, anthelmintic activity of ivermectin administered subcutaneously or orally

Psoroptes ovis, calves, control with ivermectin, dosages and routes of administration; effect on Bovicola bovis; Otobius megnini not affected

gastrointestinal parasites, horses, anthelmintic efficacy of ivermectin, adverse local or systemic reactions not observed

The activity of ivermectin against common nematode parasites of sheep was examined in 2 experiments. In the 1st experiment, 14 sheep with naturally acquired infections were assigned to 2 groups of 7 sheep each. Sheep in 1 group were treated with 200 micrograms of ivermectin/kg of body weight and the remainder served as nontreated controls. In the 2nd experiment, 15 sheep with experimentally supplemented infections (including a benzimidazole-resistant strain of Haemonchus contortus) were assigned to 3 groups of 5 each. The 1st group was treated with 200 micrograms of ivermectin/kg, the 2nd was treated with 88 mg of thiabendazole/kg, and the 3rd served as nontreated controls. Ten to 12 days after treatment, all sheep were euthanatized and necropsied, and the parasites they harbored were recovered and identified. Efficacy of ivermectin was excellent (greater than 96%) against Dictyocaulus filaria, H contortus, Ostertagia circumcinta, Marshallagia marshalli, Trichostrongylus axei, T colubriformis, and T vitrinus. Treatment was not as uniformly effective for Nematodirus spathiger (73% to 85%), N filicollis (80% to 96%), Cooperia curticei (92% to 100%), immature nematodes (92% to 100%), and early 4th-stage larvae (46% to 100%). Efficacy of thiabendazole was poor for H contortus (42%) and early 4th-stage larvae in the abomasum (52%), but approached 100% for most of the other parasites.

Strongylus vulgaris (larvae), Trichostrongylus axei (adults), ponies (exper.), efficacy of ivermectin, controlled tests