The Effect of Different Species of Eimeria with Clostridium perfringens on Performance Parameters and Induction of Clinical Necrotic Enteritis in Broiler Chickens

Abstract

Necrotic enteritis (NE) is a common disease that causes great economic loss to the broiler industry due to mortality and reduced performance. Although <i>Clostridium perfringens</i> (CP) is a necessary component of this disease, coccidia species are a well-defined predisposing factor that exacerbates the condition. Different <i>Eimeria</i> species have been reported to influence NE to different degrees. In a pair of experiments, six different <i>Eimeria</i> species were evaluated in the presence and absence of <i>C. perfringens</i>. Male broiler chicks were housed in battery cages for the duration of both experiments. Feed conversion, body weight gain, and NE mortality were reported in both experiments. Experiment 1 challenged birds with <i>E. maxima</i>, <i>E. acervulina</i>, <i>E. tenella</i>, <i>E. necatrix</i>, and <i>E. brunetti</i> at day 13 and subsequently inoculated birds with CP on days 18, 19, and 20. In the second experiment, <i>E. maxima</i>, <i>E. acervulina</i>, <i>E. tenella</i>, and <i>E. praecox</i> were inoculated on day 15 and challenged with CP on days 17, 18, 19, 20, 21, and 22 of the experiment. In the first experiment, <i>E. acervulina</i>, <i>E. brunetti</i>, <i>E. maxima</i>, and <i>E. necatrix</i> with the addition of CP all stimulated necrotic enteritis mortality. In the second experiment, <i>E. praecox</i> had minimal impact on performance during the challenge (14-23 days) while <i>E. maxima</i> + CP decreased body weight gain and increased mortality compared to the CP alone control. <i>Eimeria maxima</i> had the highest mortality (21.9%) in this experiment followed by <i>E. acervulina</i> (6.3%). The remaining <i>Eimeria</i> with added CP in the second experiment did not induce NE mortality. While the challenge with CP alone did not induce mortality, feed conversion was increased compared to the unchallenged control group. When using isolated <i>Eimeria</i> species in these experiments, disturbances created by <i>E. brunetti</i> and <i>E. maxima</i> resulted in the most-severe challenges. These experiments highlight the NE risk of these species of <i>Eimeria</i> and give insight into how other species interact with the host in a controlled CP challenge model.