Critical tests were conducted in horses (n = 11) with naturally acquired infections of benzimidazole (BZ)-resistant population-B small strongyles in 1989 and 1990. Anthelmintics administered were thiabendazole (44 mg/kg of body weight, n = 4), oxibendazole (10 mg/kg, n = 3), and oxfendazole (OFZ, 10 mg/kg; n = 4). All compounds were paste formulations administered orally except for 1 of the OFZ treatments, which was a suspension formulation given by stomach tube. Aggregate mean efficacy was calculated for all species of small strongyles, drug-resistant and nonresistant. The highest efficacy was for oxibendazole (98%) and OFZ 94%); efficacy for thiabendazole was 63%. Five genera and 16 species of small strongyles were recovered from the 11 horses, ranging from 7 to 13 species (mean, 11). Of these, 7 species were found to have resistance in variable degrees to most of the anthelmintics. These strongyles were Cyathostomum catinatum, Cyathostomum coronatum, Cylicocyclus nassatus, Cylicostephanus calicatus, Cylicostephanus goldi, Cylicostephanus longibursatus, and Cylicostephanus minutus. The large strongyle, Strongylus vulgaris, was present in afl 11 test horses, and efficacy was 100% for all drugs. Seven of the BZ-treated foals (at least 1 horse from each BZ-treatment group), were infected with S edentatus; removal was 100%.

Experimental Trichinella zimbabwensis infections were established in three baboons (Papio sp.) and four vervet monkeys (Cercopithecus aethiops) and the clinical-pathological manifestations assessed. The infected animals showed clinical signs ranging from fever, diarrhoea, periorbital oedema and muscular pain in varying degrees. One baboon became blind due to the infection. Levels of creatinine phosphokinase and lactate dehydrogenase increased to reach a peak on Day 42 post-infection (pi) for both baboons and monkeys. Blood parameters such as packed cell volume, levels of red blood cells and white blood cells did not change significantly from the normal ranges except for the levels of eosinophils which peaked above the normal ranges at Day 28 and 56 pi in baboons and at Day 56 pi in monkeys. Two baboons and two monkeys died during the course of the experiment. They were emaciated and showed lesions such as ascites, hydropericardium, congested liver and enlarged gall bladder. Histopathological findings of various muscles included a basophilic transformation of muscle cells, the disappearance of sarcomere myofibrils and basophilic sarcoplasm with the presence of Trichinella larvae in the sarcoplasm. These changes were mainly in the massetter and were of various intensities in the tail, gastrocnemius and biceps muscles. Five consecutive treatments with an oxfendazole-levamisole combination on surviving animals failed to clear the infection whereas ivermectin cleared the infection after one treatment in two monkeys and after two treatments in a baboon.

A study for about a 30-month period was done to compare strongyle control programs, using per os treatments of ivermectin (IVE) paste exclusively or alternation of 4 antiparasitic paste compounds: IVE, oxfendazole (OFZ), oxibendazole (OBZ), or pyrantel pamoate (PRT). Every 8 weeks, 1 group of horses (barn C; n = 14 to 16) was given IVE paste exclusively, and a second group (barn E; n = 16) was given the 4 antiparasitic pastes on an alternating schedule. Worm eggs and larvae per gram of feces (epg and lpg, respectively) values were determined every 2 weeks during the investigation. This study in grazing horses (mares and fillies), naturally infected with internal parasites, was conducted during the period between Oct 22, 1987 and Feb 8, 1990, with an additional observation on Mar 28, 1990. For barn-C horses, treated exclusively with IVE (200 micrograms/kg of body weight) 14 times, 2-week posttreatment mean strongyle epg and lpg (small strongyle) values were reduced 99 to 100%. Mean strongyle epg and lpg (small strongyle) values for each 2-week sample period remained low (< 20) throughout the study period, except for 1 moderate transient increase in July 1988. For the entire study period, the aggregate mean strongyle epg value was 12 and the lpg value was 6. Two-week posttreatment mean strongyle epg and lpg (small strongyle) values for barn-E horses, treated alternately with therapeutic (approx) dosage of IVE (200 micrograms/kg, 4 times), OFZ (10 mg/kg; 5 times), OBZ (10 mg/kg; 4 times), or PRT (6.6 mg base/kg; 2 times), varied within and between compounds. Posttreatment (2-week) mean epg values were reduced 100% by IVE, 0 to 100% by OFZ, 74 to 100% by OBZ, and 92 to 100% by PRT. Mean small strongyle lpg values at 2 weeks after treatment indicated reduction of: 100% for IVE, 0 to 76% for OFZ, 43 to 100% for OBZ, and 97 to 100% for PRT. For the entire study period, the aggregate mean strongyle epg value was 54 and the lpg value was 64. The epg and lpg reduction values for the 2 benzimidazoles indicated an increase in the benzimidazole-resistant segment of small strongyles. Fecal cultures for horses in both groups contained larvae of large strongyles (Strongylus vulgaris and S edentatus) only at the time of initial treatment. Treatment program evaluations included necropsy of 9 foals (56 to 203 days old), 7 born to barn-C mares and 2 born to barn-E mares. Generally, low numbers of bots (Gasterophilus intestinalis) and Habronema muscae were found in foals of both groups. Intestinal stages of immature and mature ascarids (Parascaris equorum) were also found in foals born to both groups of mares. Mature pinworms (Oxyuris equi) were found in 1 barn-C foal. Only barn-E foals had Strongyloides westeri. Small strongyles were detected in foals of both groups, up to several thousand in some. The latter finding indicates, in particular, that although barn-C mares had low small strongyle epg and lpg values throughout the study, eggs and larvae built up on pasture in sufficiently high numbers for major transmission to foals born there. Small strongyles in foals were composed of 3 genera and 10 species for barn-C foals and of 3 genera and 8 species for barn-E foals. Seasonal transmission of parasites also was observed.

A case of a cestode parasite (Choanotaenia infundibulum) egg wasfound in the intestine of chicken which was sent to the Veterinary Research Institute, Ipoh in February 2014 for post-mortem. Other parasites found in the intestine were adult tapeworm and oocyst ofcoccidia. The examination of the chicken intestine for helminth ova was undertaken using direct examination of a simple wet smear of the intestinal content which was observed under compound microscope.The cestode parasite was identified based on helminthological keys by Soulsby, 1982.