Dr. Hannele Kettunen, R & D Manager
Professor Filip Van Immerseel from the University of Ghent (Belgium) gave the first presentation in Hankkija’s webinar on 16th October, 2020. In his presentation, he emphasized the role of intestinal health on the performance of farm animals.
Check my previous blogs for an overview of the other 2 presentations by our guest speakers:
"Late gestation feeding of sows and its impact on sow and piglet performance" by Dr. Peter Kappel Theil (University of Århus)
"Challenges of large litters and their management" by Dr. Claudio Oliviero (University of Helsinki)
The usage of antimicrobial drugs peaks on certain critical phases of the life of pigs and poultry. In pigs, the postnatal and post-weaning periods are often challenged with enteric problems, while respiratory diseases are common during the transition from weaning to grower stall. In broiler chicken, E. coli often causes problems during the first five days post-hatch, while dysbiosis, necrotic enteritis and locomotory problems are typical for the period of fast growth of the third and fourth week. It is noteworthy that intestinal barrier dysfunction may lead to respiratory and locomotory problems via bacterial translocation from the intestinal lumen into bloodstream and further to other parts of the body. Bacterial isolates from liver, spleen, leg joints or vertebrae are typically derived from the intestine.
It has been well-proven that loss of epithelial barrier functions – and therefore increased gut permeability – leads to inflammation and shortening of small intestinal villi, and to impaired animal performance. Taking a good care of the gut health of animals should therefore be high on the priority list of farm managers. Good housing, tight biosecurity, and quality of the diet are necessary means for achieving the target. In addition, it is possible to amend the diet with components that support the intestinal epithelial integrity, promote epithelial cell differentiation, provide anti-inflammatory stimulate, modulate the microbiota, and decrease the virulence and colonization of pathogens.
The importance of the basement membrane – membrane that lies below the intestinal epithelium – is crucial for epithelial integrity. The epithelial cells are attached to the basement membrane, which mainly consists of collagen type IV. In a healthy gut, the basement membrane is firm and tight. However, dysbiosis and inflammation activate the expression and production of specific enzymes called matrix metalloproteinases (MMPs) which attack the collagen fibers of the basement membrane. As a result, the epithelial cells become loose and allow the entry of bacteria to the basement membrane and further to bloodstream.
The research group of professor Van Immerseel has a long experience in evaluating different feed additives and materials for their capacity to improve the homeostasis of intestinal epithelium. In the webinar he presented data demonstrating the positive effect of coniferous resin acids on the basement membrane. Diet-derived resin acids reduced the breakdown of three types of collagen in the small intestine of broiler chickens. The resin acids significantly inhibited the degradation collagen type IV by MMP7, which is specifically activated during inflammation. Moreover, resin acids significantly reduced the breakdown of two other important connective tissue proteins of the intestine: gelatin and type I collagen. Another observation of the anti-inflammatory effects of in-feed resin acids in the same experiment was the reduction of inflammatory T-lymphocytes in the duodenal epithelium.
The result indicates that the intestinal epithelium of resin acid -fed chickens is better protected against collagen-degrading enzymes than the gut of control chickens, and also against other inflammatory processes. The same kind of research has not been conducted with pigs, but the molecular mechanisms in the gut epithelium are similar in both species, so the results likely apply to pigs as well. Further work using challenge models are however needed to fully elucidate the mechanism of action of resin acids in the intestinal epithelium of monogastric farm animals.
Have a look at the article on the MOA of resin acids: Aguirre, M., Vuorenmaa, J., Kettunen, H., Valkonen, E., Callens, C., Haesebrouck, F., Ducatelle, R., Van Immerseel, F. and Goosens, E. (2019) In-feed resin acids reduce matrix metalloproteinase activity in the ileal mucosa of healthy broilers without inducing major effects on the gut microbiota. In: Veterinary Research 50: 15.