Hemorrhagic bowel syndrome in dairy cattle: Gross, histological, and microbiological characterization

Abstract

Hemorrhagic bowel syndrome (HBS) is a sporadic and fatal disease of predominantly lactating dairy cattle, characterized by segmental hemorrhage and luminal clot formation in the small intestine. Although, Clostridium perfringens and Aspergillus fumigatus have been associated with HBS, the pathogenesis and cause are currently unknown. In this study, 18 naturally occurring cases of HBS (7 necropsied immediately following euthanasia, 11 with 12–48 hour postmortem intervals) were investigated to characterize the pathology and the intestinal microbiome. Hemorrhagic bowel syndrome was characterized by a single small-intestinal, intramucosal hematoma with dissection of the lamina muscularis mucosae. In most cases necropsied immediately after euthanasia (4/7), the intestinal mucosa proximal to the hematoma contained 9 to 14, dispersed, solitary or clustered, erosions or lacerations measuring 4 to 45 mm. In 77% (37/48) of these mucosal lesions, microscopic splitting of the lamina muscularis mucosae comparable to the hematoma was present. These findings suggest the intramucosal hematoma to originate from small mucosal erosions through dissecting hemorrhage within the lamina muscularis mucosae. No invasive fungal growth was observed in any tissue. Bacteriological cultivation and nanopore sequencing showed a polymicrobial population at the hematoma and unaffected intestine, with mostly mild presence of C perfringens at selective culture. Gross and microscopic lesions, as well as the culture and sequencing results, were not in support of involvement of C perfringens or A fumigatus in the pathogenesis of HBS.

Characterization of early-stage lesions and investigation on the role of mucosal trauma in hemorrhagic bowel syndrome in cattle

“…HBS is characterized by a solitary and dissecting intramucosal hematoma at the small bowel (De Jonge et al. 2023 ). This hematoma causes intestinal obstruction, and severe intraluminal hemorrhage.…”

“…It is assumed that the hematoma develops from small mucosal erosions-lacerations, or so called early-stage lesions, through dissecting hemorrhage within the lamina muscularis mucosae (LMM), a thin bilayer of smooth muscle tissue within the mucosa (De Jonge et al. 2023 ). Etiology and pathogenesis are currently unknown.…”

“… 2014 ; De Jonge et al. 2023 ). In these previous studies, bacterial culture was often performed at the hematoma or small intestine, but not at these early-stage lesions.…”

“…Histologically, the hematoma and early-stage lesions both share the feature of detachment of the mucosa through splitting of the LMM (De Jonge et al. 2023 ). There are however no primary histological lesions which might explain the development of these early-stage lesions.…”

Epidemiology of Bovine Hemorrhagic Bowel Syndrome in Belgium and The Netherlands

“…For almost two decades, HBS was seen as some form of enteritis, with Clostridium perfringens type A receiving the most attention as a possible etiologic agent [ 5 , 6 , 7 ]. More recent work shows that HBS is characterized by an intramucosal hematoma dissecting the muscularis mucosae, which most likely develops from mucosal erosions [ 8 ]. This hematoma obstructs the intestine and ruptures, causing severe blood loss with subsequent characteristic blood clot formation in the intestinal lumen.…”