Coccidiose em Pequenos Ruminantes - UTL Repository ...

Abstract
Coccidiosis in small ruminants
Coccidiosis is a parasitism caused by parasites of the subclass Coccidia. Nevertheless, the
term is used, generally, to refer to parasitism caused by parasites of the genre EimeriaThere
is a great number of species of Eimeria which present a great host specificity. The
pathogenecity depends on the species and few are considered pathogenic enough to, just for
themselves, cause clinical manifestations of the disease. However the infections usually
involve several species and regularly assumes a subtle form that only becomes evident in
the infected animals after the occurrence of clinical signs, such as diarrhea, debility and
weight loss, leading to important economical losses.
Coccidiosis has its bigger impact in lambs with less than three months of age and it is
common in goat kids in the first six months. It is more common in intense production
systems, being influenced by many aspects, amongst which, and most important, the
handling practiced in the explorations. E. crandallis and E. ovinoidalis are considered the
more pathogenic species in sheep and in goats it is E. ninakohlyakimovae. Two studies were
carried out during the training period. The first one had the purpose of evaluating the
prevalence of Eimeria spp. in Portuguese sheep farms in extensive, semi-intensive and
intensive systems, selected by non probabilistic methods. In this study it was concluded that
the intensive systems presented a higher percentage of infected animals, being the single
infections more frequent in intensive explorations and mixed infections more frequent in the
extensive ones.
E. bakuensis was the prevalent species in the three systems of production. E. ovinoidalis,
one of the more pathogenic species, was more frequent in intensive explorations. The
second study pretended to analyze the level of excretion of oocistos of Eimeria spp in kids
between three and thirteen weeks of life in two distinct systems of production (in Portel and
in Igrejinha), In the Portel farm the kids were fed by their dams and in the Igrejinha farm they
were fed artificially. The results showed that E. caprina and E. christenseni presented
excretion values of oocistos, superior in the Portel exploration. The total Eimeria spp. oocysts
excretion excretion reached the maximum value at thirteen weeks, age in which E. arloingi,
E. caprina, E.caprovina, E. christenseni and E. hirci reached the maximum medium values of
excretion of oocyst. Amongst these, E. arloingi, presented the higher values.
Key words: coccidiosis, Eimeria spp., prevalence, management, production system.
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