The comparative analysis of infection pattern and oocyst output in in young broiler chicken Eimeria tenella, E. maxima and E. acervulina

Materials and Methods Coccidiosis is a universally important disease of poultry production. Chicken flocks free from coccidia are extremely rare and at least three species of ( and ) are commonly found in all commercial chickens [1]. The protozoan parasites of the genus multiply in the intestinal tract and cause tissue damage, resulting in interruption of feeding and digestive processes or nutrient absorption; dehydration; blood loss; and increased susceptibility to other disease agents [2]. In India, estimation has revealed that commercial broiler industry is a major suffererdue to coccidiosis wherein 95.61% of the total economic loss occurs due to the disease [3]. The seven species ( , , , , , , ) have different properties regarding localisation in the gut, pathogenicity, pre-patent period, fecundity and immunogenicity. Diagnosis of coccidiosis is based on comparison of clinical features, gut pathology in the host, and parasite properties such as morphology of different parasite stages in feacal material or intestine and pre-patent period [4]. The development of sexual stages (micro-and macro-gametocytes) and formation of oocysts were observed within epithelial cells of the small intestine (duodenum jejunum) after infection with (144 h post infection (PI) and (96 h PI) and of the caecum after infection with (136 h PI) [5].This intracellular parasite has a complex lifecycle, where it passes through asexual and sexual stages of development. The final stage of development, the oocyst, is excreted from the host and, under the appropriate conditions of temperature and humidity, undergoes a process known as sporulation, where it becomes infective. The infective form of is the highly resistant oocyst, which is shed in the feces of infected animals. species identification is based on clinical features, morphological and biological features as sizes of oocysts, sites of infection, prepatent period, sporulation time. can be easily identified based on oocyst size, while and produce unmistakable lesions [6]. The present experiment was undertaken to study thepatternofinfectionandoocystoutputof strains which were isolated in artificially infected situation in Korea, and assessed the degree of sporulation oocysts at different temperature. We also examined the histopathological observations in infection of each strain. Eimeria E. tenella, E. maxima E. acervulina