PATHOGENICITY OF EIMERIA SPECIES ISOLATED FROM CHICKEN IN THUA THIEN HUE PROVINCE

Abstract

Abstract: The present study clarifies the effect of locally isolated Eimeria species on chickens in central Vietnam. Oocysts of Eimeria species were isolated from feces suspected to be infected with coccidiosis in 3 farms in Huong Thuy district, Thua Thien Hue province. A total of 54 2-week-old chickens were randomly allocated to 2 groups: 3 replicates containing 9 chickens in each replicate. The chicken in group 1 were orally inoculated with 2×104 isolated oocysts of Eimeria species, while the chickens in group 2 were inoculated with PBS as a control. Growth performance, oocyst output, gross lesions, and histopathological lesions were measured at 5, 10 and 28 days after infection. The chicks in group 1 showed general signs of ruffled feathers, anorexia, huddling together with diarrhea and/or bloody dropping from 4–7 days post-infection. Feed intake, growth performance and body weight in group 1 were lower than those of the control chicks. The oocyst was detected in the feces of chicks in group 1 from 6–14 days post-infection, among them, the number of oocysts reach the peak at 8 days post-infection. At day 5 post-infection, the most damaged part of the intestine is the ceca with a large amount of blood in the ceca content. The histopathological lesions were detected clearly by HE staining at day 5 and 10 post-infection. In conclusion, the locally isolated oocysts of Eimeria species have high virulence to the chickens. The present study provides useful information related to the pathogenicity of Eimeria species which may contribute to coccidiosis diagnosis and treatment in poultry production.Keywords: Eimeria, coccidiosis, infection, central Vietnam