Effects of Eimeria maxima and Clostridium perfringens infections on Cecal Microbiome in Broiler Chickens Analyzed by 16S rRNA Sequencing

Authors: Li, Charles; Li, Robert; Yan, Xianghe; Lillehoj, Hyun

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/22/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Background: Necrotic enteritis (NE) and coccidiosis are considered two of the priority enteric diseases impacting poultry production in the U.S. and Europe, and are responsible for the annual economic loss of US $6 billion and $ 3 billion, respectively. NE is caused by Clostridium perfringens (CP), and is enhanced by predisposing factors to enhance CP-causing NE, such as Eimerial infection, immunosuppression, or high proteins in feed. With increasing regulation on the use of antibiotics as growth promoters, the incidence of clostridial infections has been rising. To define the effects of pathogen infections on the gut microbiota, NGS-PCR amplified 16S rRNA was used to analyze the intestine bacterial diversities. Results: To determine the changes in intestinal microflora in responses to Eimeria maxima (EM) and/or CP infection conducted in battery-cage housing, chicks were randomly assigned to the following 4 groups: 1. Naïve control, 2. EM alone, 3. CP alone, 4. EM/CP. At 2 days post CP infection or 6 days post-EM infection, Body weight was measured and lesion score in ileum was estimated. The cecal contents were sampled for DNA extraction, PCR and 16S rRNA sequencing. At 48 hr post-CP infection, the EM/CP group showed the least relative body weight gain (2.5% vs 26%, 8%, 26% for normal, EM, CP groups, respectively), and had the largest lesion score in ileum section (1.75% vs 0, 0.7, 0.1% for normal, EM, CP groups, respectively). The 16S rRNA sequencing result indicated that the cacal bacterial community was dominated by the members of the phylum Firmicutes in all the groups with higher proportions in CP and EM/CP than EM and Naïve control groups. After infections in Eimeria alone and EM/CP groups, the members of the phylum Proteobacteria increased, especially the Enterobacteriaceae. Cyanobacteria also increased greatly in EM group. In the EM/CP group, the members of genus Clostridum were much higher than the sum of those in CP and EM groups. In all infected groups, the members of the phylum Bacteroidetes decreased. These data may lead to improved understanding of bacterial interaction in the gut and is also helpful for future design of non-antibiotic alternative strategies to control NE disease.