Evaluation of Coccidiosis Vaccines in Chicken

Abstract

Coccidiosis is a serious disease affecting poultry. It is caused by a protozoan parasite of genus Eimeria that occupies the intestinal tract, causes tissue damage, and results in interruption of feeding and high mortality. This study aimed to evaluate the effect of different types of coccidial vaccines on the prevention of coccidiosis in chicken under field conditions. Chicks (n = 12; one-day-old; Avian-48 broiler) were randomly divided into 6 groups (G1, G2, G3, G4, G5, and G6), each group contained 20 chicks. The negative (G3) and positive (G6) control groups were non-vaccinated, while the remaining groups (G1, G2, G4, and G5) were vaccinated by live attenuated vaccine A (precocious strains, G1 and G4) and live non-attenuated vaccine B (wild strains, G2 and G5). G4-G6 were challenged on the 28th day by 1 x 105 sporulated oocysts of Eimeria tenella. The feed conversion rate (FCR), body weight gain (BWG), oocyst shedding, lesion score, oocyst index, and histopathology were observed and recorded in all groups. Vaccinated challenged groups (G4 and G5) had significantly lower FCR, oocyst count, and oocyst index but with higher BWG than the non-vaccinated challenged group (G6). Interestingly, G4 and G5 had lower lesion scores with no mortality as compared to G6 which showed 10% mortality. This study concludes that the usage of the anti-coccidial vaccine has significant protective efficacies in broilers with great potential with attenuated strain vaccine.