Gut microbial changes associated with Clostridial enteritis in lorikeets

Enteritis is a major cause of morbidity and mortality in lorikeets under human care. In this study, we describe recurrent outbreaks of Clostridial enteritis in lorikeet flocks at two zoos between November 2018 and September 2019. Further, we characterized cloacal microbiota and histopathologic changes associated with enteritis. Histopathologic changes included necrohemorrhagic enteritis coagulum consisting primarily of intralesional gram-positive rods bacteria (96%), transmural necrosis (64%), intestinal dilation (61%), villous fusion, atrophy, and/or blunting (39%), and replacement fibrosis within the intestinal wall (36%). We also evaluated multiple variables in relation to Clostridial enteritis risk and susceptibility, including lorikeet age, sex, species, season, diet, gut microbiota composition and diversity, history of enteritis, and presence of Clostridial species including C. perfringens and C. colinum in healthy birds.