Evaluation of the efficacy of fenbendazole against natural gastrointestinal nematodiasis in goats (Capra hircus)

Present study was conducted on 47 Barberi goats of either sex ageing around 1 year, naturally infected with strongyle nematodes. The animals were randomly divided into five groups each consisting of eight animals. The coproculture examination on day zero revealed mixed infection with the larvae of Haemonchus (74.4+/-1.02%), Oesophagostomum (23.0+/-0.45%) and Trichostrongylus (3.6+/-1.57%). The goats of groups II, III, IV and V were administered a single dose of fenbendazole at 1.25, 2.5, 5.0 and 7.5 mg/kg body weight, respectively, while the animals of group I served as untreated control. The eggs per gram of faeces (EPG) were determined in animals of all the groups before treatment (day 0) and on days 7, 14 and 21 post-treatment. The percent reduction in EPG was found to be 9.8, 9.55 and 74.14% on day 7 post-medication in animals of groups II, III and IV, respectively, whereas 100% in animals of group V. Almost same level of reduction in EPG was maintained for up to 21 days in animals of all the treatment groups. In another two groups of animals, complete deworming of animals was ensured by administering ivermectin at 200 μg/kg. These animals were individually given an experimental infection with 2700 infective larvae of Haemonchus species. The animals were divided into two groups (I, II) of three and four animals, respectively. On day 26 post-infection, EPG was determined. The animals of group II were administered a single oral dose of fenbendazole (7.5 mg/kg) while the animals of group I served as untreated control. On day 4 post-medication, faecal samples were collected for EPG determination and animals of both the groups were sacrificed, their abomasum collected and examined for Haemonchus worms. The data revealed that fenbendazole at 7.5 mg/kg was completely effective in reducing the EPG load to zero and no worms could be seen in the abomasum of treated animals. Therefore, results of the present study suggest that fenbendazole may be used at the rate of 7.5 mg/kg body weight to treat natural nematodiasis in goats. Further, it is also suggested that goats may be dewormed at least three times in a year, before monsoon, after monsoon and before the onset of winter, to minimise the chances of nematodal infection in goats.