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