Animal nutrition monogastric animals

Animal feeds are a major market, especially for monogastric animals. This is because their nutritional requirements are high and the lysine content of traditional feed such as soy or maize is low. A supplementation of feeds with individual essential amino acids is necessary because a high protein contents lead to excessive manure production, especially by pigs. 

The nutritional importance of the protease inhibitors in major foods is reasonably clear. It is known that raw soybean flour inhibits growth in rats, chickens and some other monogastric animals (118) and death can result (119). It is also known that the presence of soybean inhibitor in the small intestine increases the secretion of a hormonal pancreozymic-like substance that markedly stimulates external secretion by the pancreas (120). The presence of active proteolytic enzyme inhibitors in the small intestine increases the production and secretion of proteolytic enzymes by the pancreas, presumably to compensate for their loss by complexation (121-123). This results in hyperplasia of some of the pancreatic cells and enlargement of the pancreas. 

Sorghum grain (Sorghum bicolor (L) Moench). The nutritional values for monogastric animals correspond to low-tannin varieties (n = 790). 

The molybdenum requirement of ruminants was calculated to be <100 pg/kg dry matter of ration monogastric animals may need even less [36]. For human adults it is calculated to be 25 pg/day [37]. Apart from parenteral nutrition molybdenum deficiency need not be reckoned with in animals and humans. 

Another field of increasing interest for public opinion nowadays is animal welfare. Quite some research deals with the interaction between nutrition and animal health on one side, and the possibility to replace in vivo with in vitro experiments on the other side. The databases available today are impressive and the possibility to share and get information worldwide makes it easier to develop models to predict both animal requirements and feed nutritive values. Indeed modeling is extensively dealt with in the symposium and deserves two sessions, one dedicated to ruminants and the other to monogastrics. 

Nutrition. Zinc is essential to the proper functioning of plants and animals and, as zinc sulfate and oxide, it is used as a feed supplement (49—51) (see Mineral nutrients Feedsand feed additives). Most crops use less than a kilogram of zinc per 1000 m per year, so that zinc salts added at 1.3—4.5 kg/ha gradually build up the zinc reserve (52). Animals, including humans, store relatively Htde available zinc and, thus, require a constant supply in the diet. For instance, beef cattle require 10—30 mg/kg dry feed, dairy cattle 40 mg/kg, and breeding hens 65 mg/kg. Zinc from plants is considered less available to monogastric aminals than zinc from animal protein. 

Bedford MR (2000) Exogenous enzymes in monogastric nutrition - their current value and future benefits. Animal Feed Sci Technol 86(1) 1-13... 

Methionine was first reported from casein in 1922 by Mueller. It is a limiting amino acid in the monogastric s feed and the addition of synthetic methionine in animal feed started from the 1950s. The addition of amino acids in the feed increases the nutritional quality and conversion efficiency of low protein feed and hence lowers the feed cost. Methionine is commercially produced by either chemical synthesis, enzymatic methods or microbial fermentation. Methionine has an advantage that it can be supplied to animal feed as a chemically produced racemate or a racemic mixture as the mammals are able to convert it to utilizable form with a methionine racemase enzyme. Chemical production uses harmful chemicals and production from protein hydrolysates requires several separation steps. Chemical synthesis produces a racemic mixture and is acetylated to produce L-methionine. Microbial fermentation overcomes these difficulties and has added advantages over the racemate that it helps optimal nutrient utihzation. 

Van Weerden I, van Weerden E J and Huisman J (eds) 1992 Nutritive and Digestive Physiology in Monogastric Farm Animals, Wageningen, Pudoc. 

Formulation of a ration or diet requires knowledge of the nutrient requirements of the animal (discussed in this part) and the nutritional value of the foods (discussed in Part 3) and, in order to combine these two, the amount of foods the animal can consume. Therefore, Chapter 17 gives details of factors affecting food intake in both monogastrics and ruminants and the methods used to predict food intake. 

In monogastric, and particularly human, nutrition the term dietary fibre is often used and attention has been focused on its importance in relation to health. Dietary fibre (DF) was defined as lignin plus those polysaccharides that cannot be digested by monogastric endogenous enzymes. Initially epidemiological studies linked a lack of DF to constipation, gut and bowel disorders, cardiovascular disease and type 2 diabetes however, the causes of such diseases are multifactorial and in some cases it is not just DF per se that has the beneficial effects but other aspects of the diet also (e.g. antioxidants). Nevertheless, DF is a major component related to health in humans and it has equally important effects in animals (see below). 

Nutritional value does not appear to be compromised by extrusion. Complexed lipids are digestible by monogastric and ruminant animals. Essential and omega fatty acids in extruded foods are more susceptible to lipid oxidation, and thus, reduced nutritional value, but few studies have examined this potential problem. 

Although tannins appear to protect protein from microbial attack in the rumen, their ultimate effects on ruminant nutrition may depend upon how available this bypass protein is to the animal. According to Price and Butler (1980), the same factors that cause tannins to have a deleterious effect on monogastric nutrition, will presumably be important in the post-rumen digestive tract. If the tannin-protein complex does not dissociate in the abomasum or intestine, there will be no benefit to the animal from the protein having been protected in the rumen. If it does dissociate, the liberated tannin may damage the intestinal tract or form new complexes at some point with endogenous proteins. 

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