Dynamics of lamb coccidiosis in indoor management systems

Abstract

SummaryInvasions of protozoa belonging to the genus Eimeria are a global problem in sheep farming. The clinical course of eimeriosis occurs almost exclusively in lambs. In adult sheep coccydiosis often has an asymptomatic course which, however, is not without an impact on animal conditions. Large flock density and related contamination of the environment with oocysts is conducive to a high extensiveness of the invasion. The aim of the study was to analyze the prevalence and intensity of Eimeria invasion in lambs kept in confined management systems in order to establish the key periods of the course of invasions and schedules for prevention programs. The parasitological examination was conducted on samples of feces collected directly from the rectum of 96 lambs every 14 days at the following time points: the 28 th , 42 nd , 56 th , 70 th and 100 th days of life. The assessment involved the invasion extensity established using a flotation method and invasion intensity expressed as the number of oocysts per gram of feces (OPG) established by using the McMaster technique. On the basis of morphometric parameters of isolated oocysts, the species of coccidia in the studied animals were determined. During the whole study period, the invasion extensity grew from the minimum of 17.6% (CI ± 95%; 9.6-25.6) on day 28 to the maximum of 95.9% (CI ± 95%; 95.3-100.0) on day 100. The average growth in the invasion extensity in the flock was 19.6% every 14 days. The average invasion intensity in the study period was 3039.2 OPG (min-max 50-58,800; SEM 440.2), with the highest excretion of oocysts observed on day 42 of the lambs' life. The average OPG value on this day was 6783.8, and dropped at subsequent measurement points. The experiment revealed exclusively multi-species invasions. In total, seven species of coccidia were found in the studied animals within the study period. These were: E. bakuensis, E. faurei, E. intricata, E. ovinoidalis, E. pallida, E. parva and E. crandallis.