1. Butyric acid in animal nutrition
Abstract Organic acids like butyric acid are used for many applications in human and animal nutrition. The use for the preservation of foodstuffs or single components is accepted all over the world as a very effective method to control growth of bacteria (E.coli, Salmonella), mold and yeast. There is ample evidence that organic acids can improve performance of piglets and to a lower extent also those of growing pigs and chicks. In contrast to other organic acids, butyric acid seems also be effective as nutrient of the intestinal mucosa. In this role it acts as a stimulator of the intestinal trophism in terms of renewal of basal cells, increasing density and length of villi, and also various other factors related to gut integrity. Through these effects butyrate can modulate the intestinal flora. The aim of this review is to evaluate the literature data about the effect of butyric acid in monogastric animals. Special attention is given to its effect on gut integrity in these animals.
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Butyric acid is widely distributed in nature as normal constituent in milk of sows, cows and other species. In addition, it is produced in the intestine subsequent to digestive metabolic degradation of fibers and carbohydrates. Bacteria which produce butyric acid mainly include sugar fermenters such as Clostridium spp., Eubacterium spp., Fusobacterium spp., Butyrivibrio spp. The pKa value of butyric acid is 4.82 and comparable with that of acetic and propionic acids. The NE value for pigs is 17.65 MJ/kg and the ME value for poultry 22.45 MJ/kg. Butyric acid is available in the liquid form, but also as Na and Ca salts. In practice, there are limits of the use in liquid form, since it is has as an unpleasant odour and the volatility is very high. Thus, in practice, mainly the salts of butyric acid are used, since they are more stable and less odorous. In an aqueous solution sodium butyrate easily dissociates into butyric acid. The salt forms of butyric acid do not have the potency of reducing the pH of the environmental, because of the replacement in salts of the H+ by Na+ or Ca2+.
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Novyrate – Optimal solution that supports Gut Integrity