AUTHOR=He Wanwei , Goes Emanuele C. , Wakaruk Jeremy , Barreda Daniel R. , Korver Douglas R. 

TITLE=A Poultry Subclinical Necrotic Enteritis Disease Model Based on Natural Clostridium perfringens Uptake

JOURNAL=Frontiers in Physiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.788592

DOI=10.3389/fphys.2022.788592

ISSN=1664-042X

ABSTRACT=<p>Necrotic enteritis (NE) in poultry is an opportunistic infection caused by <italic>Clostridium perfringens</italic>. Well-known as a multifactorial disease, NE development is under the influence of a wide range of environmental risk factors that promote the proliferation of pathogenic <italic>C. perfringens</italic> at the expense of nonpathogenic strains. Current <italic>in vivo</italic> NE challenge models typically incorporate pre-exposure to disease risk factors, in combination with exogenous <italic>C. perfringens</italic> inoculation. Our goal was to enhance current models using a natural uptake of <italic>C. perfringens</italic> from the barn environment to produce a subclinical infection. We incorporated access to litter, coccidial exposure (either 10× or 15× of the manufacturer-recommended Coccivac B52 <italic>Eimeria</italic> vaccine challenge; provided unspecified doses of <italic>E. acervulina, E. mivati, E. tenella</italic>, and two strains of <italic>E. maxima</italic>), feed composition, and feed withdrawal stress, and achieved the commonly observed NE infection peak at 3 weeks post-hatch. NE severity was evaluated based on gut lesion pathology, clinical signs, and mortality rate. Under cage-reared conditions, 15× coccidial vaccine-challenged birds showed overall NE lesion prevalence that was 8-fold higher than 10× coccidial vaccine-challenged birds. NE-associated mortality was observed only in a floor-reared flock after a 15× coccidial vaccine challenge.</p>