Effects of ochratoxin A on membrane phospholipids of the intestine of broiler chickens, practical consequences.

ABSTRACT

Ochratoxin A (OTA) is a mycotoxin produced by various species of Aspergillus and Penicillium. Ochratoxin A was classified as a group 2B carcinogen and is one of the major intestinal pathogenic mycotoxins. One of the most frequent modes of intoxication is consumption of contaminated food with mycotoxins. Feed represents the major cost and has a direct impact on the economical viability of broiler's production system, since it must contain the necessary elements that allow the animal to express the maximum genetic potential while providing its nutritional requirements. Thus, the animal has to digest the feed and absorb its nutrients, which is in direct correlation with the gastrointestinal tract, especially the small intestine and the development of the mucosal surface area. Once ingested, OTA is absorbed by passive diffusion, mainly the jejunum. Ochratoxin A's presence affects lipid membranes and could lead to the degradation of their normal structure and functionality. All of these effects contribute to the development of malabsorption. It was very interesting to study the effect of OTA on the layer of phospholipids of the bowel. The experimental group received OTA (0.05 to mg/kg BW) through an intra-peritoneal injection, every other day for 21 days. We noted that feed conversion ratio and average daily gain were reduced. Histological studies showed important alterations at the level of the mucosal membrane of the intestine (villosities, crypts) following intra-peritoneal administration of the mycotoxin. Thinning and enlargement at the base of the villosities, hyperplasia and crypts in irregular forms, blunting and denudation were observed through the examination of intestinal morphology. Biochemical studies, such as total lipid and phospholipid compositions, allowed us to have more detailed results. All identified mucosal phospholipids were modified, particularly the phosphatidylcholine (PC) and the phosphatidylethanolamine (PE) in the jejunum mucosa. In fact, there was a decrease by 55.81% for PC, 56.66% for PE, while a significant increase by 32.91% was noted for phosphatidylserine in the jejunum. It was very interesting to study the effect of OTA on the phospholipids layer of the bowel, as the mucous membrane of the small intestine represents the main site of absorption and transformation of nutriments. To avoid such disturbances and prevent the effects of the OTA, precautions must be taken to inhibit mold growth at the level of the feed manufactory units. Phosphatidylcholine and PE administrations may represent an option that could allow reestablishment of phospholipid equilibrium in the intestine.