Gross and histomorphometric differences in the caecum of domesticated cattle and water buffalo

Abstract

Domesticated cattle and water buffaloes are major dairy animals and considered alike morphologically. Recent studies highlighted differences in the behaviour, vital clinical parameters, the topography of abdominal organs and clinical manifestations of some disease conditions in cattle and buffaloes. This study investigated species differences in the gross and histomorphometry of the caecum and ileocaecal mesentery in domestic cattle and water buffalo. The study was conducted on 8 bovine cadavers (4 crossbred cattle and 4 Murrah water buffaloes that were euthanized due to causes other than gastrointestinal disorders) to evaluate the species-specific gross and histomorphometric differences in the caecum at the apex, and body including ileocaecal mesentery.
Histomorphometry was done using H&E, Picrosirius Red and Verhoeff ’s Elastic stain.
On gross examination, the mean length of the caecal apex (devoid of ileocaecal mesentery) and length of the ileocaecal mesentery were significantly less whereas the length and diameter of the caecal body were non-significantly less in buffaloes as compared to cattle. On histomorphometry, the thickness of the total caecal wall (at apex and body) along with its histological layers and the sub-epithelial connective tissue layer of the ileocaecal mesentery was also significantly less in buffaloes as compared to that in cattle. The collagen fibres were significantly less, quantitatively and qualitatively, in the caecal body and ileocaecal mesentery
of buffaloes as compared to that in cattle.
In conclusions, the caecum of domestic water buffalo and cattle show species specific gross and histomorphometric differences, which might have implications concerning the pathophysiology of caecal disorders or their sequel including surgical exploration.