Ruminant Eimeria spp. infections in Estonia
2002
Kaarma, A. | Maegi, E. (Academical Agricultural Society, Tartu (Estonia))
Eimeria spp. infections of cattle and sheep have worldwide distribution. Acute form of the disease is characterized by diarrhea, depression, loss of live weight and the presence of faecal oocysts. Eimeria spp. population biology was investigated in estonian conditions in several sheep flocks of various districts. According to our results, 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. All the lambs in our observation groups have born in winter from December to February and the grazing period was 5 months: from May to October. The results of our trials show that lambs 1-4 months of age had high incidence of invasion. According to our conclusion, clinical signs approximately in 5 per cent of lambs and young sheep have been registered. Despite the fact that ordinarily older sheep rarely develop the disease, they carry the parasites and continuously excrete small number of oocysts. Extent of invasion in breeding ewes occurred to be relatively high: in mean up to 17.5-25 per cent of investigated flocks. Parasite population dynamics appeared to be in dependence on several endogenous and exogenous 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
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