The large intestine in horses is a significant component of the digestive system, responsible for the fermentation and absorption of nutrients. It comprises several sections, including the cecum, colon, and rectum. The large intestine hosts a diverse microbial population that aids in the breakdown of fibrous plant material, facilitating the digestion of cellulose and the production of volatile fatty acids, which are a primary energy source for horses. Additionally, it plays a role in the absorption of water and electrolytes. The large intestine's structure and function are essential for maintaining digestive health and overall well-being in horses. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and clinical aspects of the equine large intestine.
ADAMS KM.The ciliate population of the large intestine of the horse shows large, daily variations. The ventral colon is the site where the ciliate fauna varies most. Two species, Cycloposthium edentatum and C. dentiferum, became established in the large intestine after passage through the stomach and small intestine. The introduction of new species into the ventral colon caused significant changes in the fauna of that part of the gut.
Giacominelli-Stuffler R, Frangipane di Regalbono A, Traversa D, Geurden T, Marcer F, Di Francesco A, Angelini C, di Cesare A, Storelli MM....Leukotrienes are products of the arachidonic acid metabolism and act as potent inflammatory mediators modulating the immune response and various physiological processes. This study evaluated the expression and activity of 5-lipoxygenase (5-LOX), the enzyme that catalyzes the first two steps in the biosynthesis of leukotrienes, in horses infected by larval cyathostomins. Tissue samples from dorsal and ventral colon, and from the cecum were collected from 16 horses slaughtered for human consumption. Samples were analyzed to estimate the burdens of encysted cyathostomin larvae and adult luminal s...
Smith L, Moran AW, Al-Rammahi M, Daly K, Shirazi-Beechey SP.Studies carried out in several species have demonstrated that detection of low-calorie sweeteners in the lumen of the intestine, by the sweet receptor, T1R2-T1R3, initiates a signaling pathway leading to enhanced expression and activity of intestinal Na/glucose cotransporter 1, SGLT1. This results in an increased gut capacity to absorb glucose, sodium chloride and water, the basis for oral rehydration therapy. Horses express T1R2, T1R3 and downstream signaling elements in the intestinal tissue. As such, the potential of sweetener-stimulation of T1R2-T1R3 leading to upregulation of SGLT1 allows...
Kramer AJ, Meziara Wilson T, Kimura S, Groover E, DeLeon-Carnes M, Neto RLALT.A 23-y-old gelding was presented to a veterinary teaching hospital with a history of chronic, refractory diarrhea. Clinically, the horse was in poor body condition, with a thickened and corrugated large intestine identified by transcutaneous abdominal ultrasonography. At postmortem examination following euthanasia, the large colon and cecum had segmental thickening of the intestinal wall with innumerable mucosal ulcers and prominent polypoid mucosal masses. Many mesenteric and hepatic lymph nodes were enlarged. Histology revealed granulomatous and ulcerative typhlocolitis and granulomatous lym...
Bishop RC, Arrington JV, Wilkins PA, McCoy AM.Peritoneal fluid (PF) is intimately associated with the gastrointestinal tract, and changes in the PF may directly reflect abdominal pathology. We aimed to quantify differences in the PF proteome between intestinal lesion type (ischemic vs. non-ischemic) and location (small vs. large intestine). PF samples were collected at hospital admission from horses presenting for abdominal pain (colic). Cases were clinically categorized by lesion type and location after resolution (10 per group). PF proteins were extracted and quantified by label-free liquid chromatography-tandem mass spectroscopy. Data ...
Burns JJ, Stull J, John E, Doyle A.For horses presenting for colic to a referral hospital in Atlantic Canada, we aimed to describe clinical findings, diagnosis, treatment, and outcome for draft breeds; identify associations between clinical findings, diagnosis, treatment, and outcome for draft compared to nondraft breeds; and identify the overall impact of draft breed on mortality. Unassigned: A retrospective review of equine colic cases presenting to the Atlantic Veterinary College (2004 to 2023). Logistic regression models were used to assess associations between parameters and draft breed and mortality. Unassigned: A total o...
