Review/Oorsig Volume 22, Issue 02 - Page 6

Oorsig/Review Figure 6 - Comparison of Swine and Ruminal Intestinal Morphology. Providing zinc from Zinpro Performance Minerals improves intestinal morphology/integrity compared to that of non-heat-stressed animals fed the control diet. Key: Intestinal morphology images for swine are shown in red and ruminant are shown in blue. Upper left, thermal-neutral control animals; Upper right, thermal-neutral pair-fed animals (reduced feed intake); Lower left, heat- stressed animals with no zinc from Zinpro Performance Minerals supplementation; Lower right, heat-stressed animals fed 40 ppm zinc from Zinpro Performance Minerals. can also decrease intestinal integrity and increase circulating endotoxins in production animals (Pearce et al., 2013, 2014). Replacing inorganic zinc with zinc from complexed organic trace minerals has been shown to mitigate potential gut leakage in pigs associated with acute and chronic heat stress (Pearce et al., 2015; Mayorga, et al., 2017). Improved gut integrity resulted in decreased presence of TNFα in blood, suggesting that zinc from complexed organic trace minerals can help prevent some of the endotoxin’s negative effects by reducing the amount of endotoxins that enter circulation. In addition, the gut morphology of pigs fed zinc from complexed organic trace minerals was more similar to pigs housed under thermal-neutral conditions (Figure 6). The gastrointestinal tract (GIT) is one of the largest immune organs in the body. When pathogens are ingested and reach the lumen of the GIT, they have not yet been absorbed into the animal’s body. Maintaining GIT epithelium integrity is of the utmost importance to prevent pathogens from invading the body, similar to that of the skin. Several key anatomical features of the intestinal epithelium aid its ability to maintain the barrier between pathogens in the gut lumen and the internal body. The mucosal epithelial layer contains goblet cells, which secrete mucous and 6 mucins that provide the initial protection layer over the enterocytes of the intestinal epithelium. In addition, these enterocytes are “stitched” together by tight junction complexes (Figure 5). This region is important for limiting the amount of harmful bacteria and contents of the intestinal lumen from entering the blood stream. Similar to what was observed in heat- stressed pigs, feeding zinc from complexed organic trace minerals helped maintain intestinal morphology/integrity of heat-stressed steers in a manner similar to steers housed under thermal-neutral conditions (Figure 6; Abuajameh et al., 2016). In this study, feeding zinc from complexed organic trace minerals in place of inorganic zinc improved heat tolerance of steers, as evidenced by increased dry matter intake and decreased rectal temperatures. The ability to absorb nutrients from the gut may have been improved for steers fed zinc from complexed organic trace minerals, as these animals had decreased duodenal villi width and increased jejunum villi height and height:crypt depth, as compared with heat-stressed steers fed only inorganic zinc. Weaning presents another potential stressor for almost every mammalian species. Data in piglets indicates that feeding complexed organic trace minerals has a positive impact on villi anatomy