Dynamics of Eimeria spp. infection depending on sheep age groups and keeping conditions
1999
Kaarma, A. | Maegi, E. (Estonian Agricultural Univ., Tartu (Estonia). Faculty of Veterinary Science)
Eimeria spp. population biology was investigated in several sheep flocks of various Estonian districts. Dynamics of infection depend on sheep age groups and local keeping conditions on farms. Flotation method of coprological investigations was used to estimate the extent of invasion and all sheep allowed to clinical observations. The lambs have born in winter from December to February and the beginning of grazing period was in May. The results of our trials are demonstrated. According to our results, clinical signs approximately in 5 per cent of lambs and young sheep have been registered. Lambs 1-4 months of age had high incidence of invasion: Eimeria spp. oocysts have been found in 50 per cent of the investigated animals. Despite the fact that ordinarily older sheep rarely develop the disease, in breeding ewes the extent of invasion occurred to be relatively high. Parasite population dynamics appeared to be in dependence on several endogenous and endogenous factors in sheep flocks. Separate grazing of ewes and lambs born in winter period did not affect essentially the distribution level of invasion in pasture period
显示更多 [+] 显示较少 [-]