Halofuginone lactate in the control of cryptosporidiosis in neonate kids.

Cryptosporidiosis is a major disease in 5-20 days old kids which causes mor bidity (diarrhoea) and mortality reaching more than 60 %. Only few drugs pr esent significant efficacy in preventing the infection in ruminants. In a g oat farm suffering an epizootic form of cryptosporidiosis in kids, the prev entive efficacy of halofuginone lactate (RU38788, Halocur(ND)) was assessed . Immediately after birth, kids were separated from their dams, were given colostrum twice on day 1 and from day 2 onwards were given milk replacer wi th automatic device. Halofuginone was individually given to female kids (n = 48) from d3 to d9 at 100 mu g/kgBW/d whereas male kids (n = 21) were kept as untreated controls. Twice a week individual faecal samples as well as c linical scoring and weighing were performed until d28. Oocyst output was as sessed with HEINE staining in a semi-quantitative method according to a sco ring ranging from 0 to 5. In control kids, the development of the infection was as usual: peaks of pr evalence and intensity of excretion between d7 and d12 with oocyst scoring ranging from 3.5 and 4.5 and disappearance of faecal oocysts beyond 21d. In treated animals, the prevalence and intensity of oocyst output were decrea sed, the effect being more pronounced between d3 and day 7 than between d7 and d9. After d9, the oocyst output increased and then exceeded those of co ntrol. The mortality rate at d28 was reduced in the treated group compared to control one, 35.4 vs 61.9 %. Finally, halofuginone showed a clear activi ty against kid cryptosporidiosis in natural conditions. Nevertheless, this efficacy was partial and additional experiments are needed about the length of the administration and the dose rate.