TRANSMISSION OF FOOTROT IN MIGRATORY SHEEP AND GOATS OF NEPAL

Combined sheep and goat flocks of Kaski and Lamjung Districts in the W estern Development Region of Nepal, where footrot is endemic, were mon itored throughout the period of migration to and from alpine pastures (3700-4500 m above sea level (a.s.l.)) for 2 consecutive years to stud y the epidemiological aspects of disease transmission, During 1991, tw o whole flocks of one village (Ghanpokhara) were observed; during 1992 , a sample of 160 sheep and 40 goats from ten different flocks of thre e villages (Siklis, Tangting and Ghanpokhara) were observed. The perio d of upward migration through the forest (May-June) was found to be as sociated with footrot transmission (more than 60% of sheep and about 3 0% of goats became infected), so this was the critical period for shee p and goats to be protected. The alpine pastures, though wet, were not conducive to transmission of footrot, and a very low proportion of an imals acquired the disease during descending migration through the for est (October-November). The period of maximum transmission was found t o coincide with increasing rainfall and temperature. Both Baruwal shee p and Sinhal goats were found to be affected with footrot. The observa tion on the Ghanpokhara flocks in 1991 suggested that footrot was more prevalent in sheep than goats, However, when samples from different f locks were observed in 1992 the prevalence of footrot in goats and she ep was not significantly different. In contrast to sheep, footrot in g oats was more likely to be confined to the interdigital skin, An impro ved understanding of the epidemiology of footrot in migratory goats an d sheep was obtained from these observations. This is expected to resu lt in improved management of the disease.