Topic:Fenbendazole
Fenbendazole is an anthelmintic drug commonly used in horses to treat and control gastrointestinal parasites, such as strongyles, ascarids, and pinworms. It functions by disrupting the energy metabolism of the parasites, leading to their eventual death. Fenbendazole is administered orally and is available in various formulations, including paste and pellet forms. The drug is generally well-tolerated by horses, with a wide margin of safety. This page assembles peer-reviewed research studies and scholarly articles that explore the pharmacokinetics, efficacy, and safety of fenbendazole in equine populations, as well as its role in parasite management programs.
Field efficacy of ivermectin, fenbendazole and pyrantel embonate paste anthelmintics in horses. Three anthelmintic pastes were compared in terms of their ability to suppress the output of parasite eggs in the faeces of 108 grazing horses at four sites in Britain; the horses were treated once with either ivermectin, fenbendazole or pyrantel. At each site, the horses grazed together throughout the trials which took place during the summers of 1985 and 1986. The median periods before parasite eggs reappeared in faeces were 70 days for ivermectin, 14 days for fenbendazole and 39 days for pyrantel embonate. Geometric mean faecal egg counts in the groups treated with ivermectin and pyrantel we...
Evaluation of fenbendazole for larvacidal effect in experimentally induced Parascaris equorum infections in pony foals. Fifteen pony foals were inoculated with 1,500 +/- 298.7 infective Parascaris equorum eggs. The foals were assigned to 3 treatment groups. Treatments included 10 mg of fenbendazole/kg given once on postinoculation day (PID) 11, 10 mg of fenbendazole/kg given daily on PID 11 to 15, and no treatment (controls). The foals were euthanatized on PID 25 and examined for P equorum larvae in the small intestine, lungs, and liver. Significantly (P less than 0.05) lower mean numbers of P equorum larvae were found in the small intestine of foals treated on PID 11 to 15 (1.4 [range, 0 to 6]) than in the sma...
Fenbendazole in equids: further controlled tests with emphasis on activity of multiple doses against naturally occurring infections of migratory large strongyles. Two controlled tests (experiments D and E) were done to evaluate a fenbendazole (FBZ) paste dosage regimen (10 mg/kg once a day for 5 days) for activity against naturally occurring infections of migrating Strongylus vulgaris and S edentatus in the mesenteric arteries and ventral abdominal wall, respectively. Data were also obtained on other internal parasites of the gastrointestinal tract and eyes in experiment E. Eight pony yearlings were used in experiment D (4 treated and 4 nontreated) and 6 horse weanlings were used in experiment E (3 treated and 3 nontreated). Intervals, expressed as days...
Granulomatous colitis associated with small strongyle larvae in a horse. Horses presented with chronic weight loss are difficult to manage clinically. A diagnosis of granulomatous colitis due to mucosal stages of cyathostomes (small strongyles) should be considered in those cases exhibiting weight loss, intermittent diarrhea, hypoalbuminemia, increased serum globulins, and low fecal egg counts. Treatment can be attempted with larva-cidal doses of fenbendazole or ivermectin. Clinical and necropsy findings in one such case are presented.
Effectiveness of fenbendazole against later 4th-stage Strongylus vulgaris in ponies. Twelve pony foals (reared worm-free) were inoculated with Strongylus vulgaris. Approximately 8 weeks later, 4 of the foals were given fenbendazole (10% suspension) at a dosage rate of 10 mg/kg of body weight daily for 5 days and 4 foals were given the suspension at a dosage rate of 50 mg/kg daily for 3 days; the remaining foals were given a placebo. All treatments were administered by stomach tube. Fenbendazole was 99.6 and 97.9% effective in the 2 treatment groups, respectively, in eliminating later 4th-stage S vulgaris larvae located near the origin of major intestinal arteries. On microscop...
Controlled tests of fenbendazole against migrating Strongylus vulgaris in ponies. Sixteen pony foals were reared worm-free and inoculated with Strongylus vulgaris. On day 7 after inoculation, 12 ponies were given a fenbendazole 10% suspension at dose rate of 50 mg/kg of body weight by stomach tube. On day 8 after inoculation, 8 of these ponies were given the 2nd treatment of the anthelmintic and on day 9, 4 of these ponies were given the 3rd treatment. (The other 4 of the 16 ponies were given only tap water, as controls.) The ponies were necropsied at death or on day 28 after inoculation. Fenbendazole was effective in minimizing the appearance of clinical signs associated w...
Apparent inactivity of several antiparasitic compounds against the eyeworm Thelazia lacrymalis in equids. Activity of 15 compounds, given alone or in mixtures [butamisole, cambendazole, caviphos, febantel (alone or with trichlorfon), fenbendazole, ivermectin, levamisole-piperazine, oxfendazole, oxibendazole, pyrantel pamoate (alone or with piperazine-carbon disulfide complex), thiabendazole (alone or with piperazine or with trichlorfon), tioxidazole, and trichlorfon], against Thelazia lacrymalis was evaluated in 102 equids. Determination of activity was based on comparison of infection rate in treated animals examined at necropsy with infection rate of dead equids in our contemporary surveys. None...
Anthelmintic efficacy fenbendazole paste in equines. A single oral dose of fenbendazole (FBZ) paste at 7,5 mg/kg body mass was given to 5 horses. It was highly effective against adults of the following genera: Cyathostomum, Cylicostephanus, Cylicondontophorus, Poteriostomum, Cylicocyclus, Triodontophorus, Oesophagodontus (and other genera belonging to the subfamily Cyathostominae). Similarly, high efficacy was obtained against the adults of the following species: Oxyuris equi, Strongylus vulgaris, Strongylus equinus and Probstmayria vivipara. These results were confirmed in 12 horses and in addition FBZ at 7,5 mg/kg was highly effective against ...
Anthelmintic efficiency of fenbendazole in equines. A single oral dose of fenbendazole (FBZ) at 10mg/kg body mass was given to 5 donkeys. A further 5 donkeys were dosed with a medicated lick (1 mg FBZ/g lick) until the oral consumption was 10mg/kg body mass. In both trials FBZ was highly effective against adults of the following genera: Cyathostomum, Cylicocyelus, Cylicostephanus, Cylicodontophorus, Poteriostomum, Cabellonema, Craterostomum and Triodontophorus; similarly high efficiency was obtained against the following species: Habronema majus, Habronema musca, Strongylus vulgaris and Oxyuris equi and worms identified as belonging to the subf...
Studies on the efficacy of fenbendazole used in a divided dosage regime against strongyle infections in ponies. The efficacy of a fenbendazole divided dose regime against immature stages of Trichonema spp, Strongylus vulgaris and Strongylus edentatus was evaluated. A group of 8 naturally infected 30 to 36-month-old ponies was divided into 2 equal groups on the basis of previous treatment and faecal egg counts, one group being treated with 7.5 mg/kg bwt of fenbendazole daily for 5 days. This treatment regime removed 80 per cent of migrating S vulgaris larvae, 100 per cent of migrating S edentatus larvae and 95 per cent of the mucosal stages of Trichonema spp. In addition, a virtual 100 per cent eliminati...
Studies on fenbendazole for treating lung and intestinal parasites in horses and donkeys. The efficacy of orally administered fenbendazole on lung and intestinal parasitism in equids was investigated in a mixed herd of pony mares, jenny donkeys and foals. A single dose of 7.5 mg fenbendazole/kg body weight effectively removed intestinal parasites from the ponies, donkeys and foals, but higher doses and repeated treatments failed to eliminate lungworm infections in donkeys. The finding of eosinophilia proved useful in detecting lungworm infections in donkeys.
Studies on the faecal egg output of horses after treatment with fenbendazole. Examination of faecal egg counts in horses and ponies has shown that after treatment with fenbendazole at dose levels of 7.5, 45 and 60 mg/kg, faeces remained free from strongyle eggs for periods of 6 to 18 weeks. The significance of these results is discussed in relation to routine anthelmintic treatment of horses. In particular, the activity of fenbendazole against mucosal stages of strongyle parasites allows for treatment to be recommended at less frequent intervals than when using other anthelmintics.
The efficacy of fenbendazole in the control of immature strongyle infections in ponies. The efficacy of fenbendazole against immature stages of Trichonema spp., Strongylus vulgaris and Strongylus edentatus was evaluated. Naturally infected 6 to 12 month old ponies were given single, oral doses of 0, 15, 30 and 60 mg/kg of body weight. A dose response relationship was noted between increasing dose levels and efficiency against larval trichonemes and migrating stages of S. vulgaris and S. edentatus. Dose levels of 30 mg/kg and higher removed 93 per cent of mucosal stages of Trichonema spp., while doses of 60 mg/kg removed 83 per cent and 89 per cent of the migrating larvae of S. vu...