Monogastric species

To obtain optimal performance of farm animals, foHc acid supplementation is required (86) and as is the case with most of the vitamins, the majority of worldwide consumption is as feed supplements. The foHc acid requirement for chickens and pigs is about 0.2—0.5 mg of foHc acid/kg diet and 0.3 mg/kg diet, respectively. Increased amounts, 0.5—1.0 mg/kg feed for chickens and 0.5—2.0 mg/kg for swiae, are recommended under commercial production conditions (87). The degree of intestinal foHc acid synthesis and the utilization by the animal dictates the foHc acid requirements for monogastric species. Also, the self-synthesis of folaciais dependent on dietary composition (88). 

Even though the horse is a monogastric species, the stomach has a small capacity (8.5% of the gastrointestinal tract) compared with that of the pig (29%) and the dog (62%). Expressed on the basis of volume capacity, the stomach of the horse, pig, and dog can... 

Significant differences in the extent of distribution of drugs, particularly lipid-soluble organic bases, are usual between ruminant and monogastric species. After parenteral administration, lipophilic bases diffuse passively from the systemic circulation into ruminal fluid (pH 5.5-6.5), where they become trapped by ionization. These drugs are slowly reabsorbed or, if they possess fimctional groups suitable for metabolism by hydrolysis or reduction, they may be partially inactivated by ruminal micro-organisms. 

In monogastric species iron absorption takes place primarily in the upper small intestine (1). Not all the iron present in foods is absorbed into the body. In the normal adult with adequate stores of iron, usually less than 10% of the iron in foods is absorbed (2). Because of the body s limited capacity to excrete iron, the ability to refrain from absorbing unneeded iron is regulated in the duodenum and is referred to as the mucosal block (1). When the requirement for iron increases as in growth and pregnancy and in various disease and deficiency states, the mucosal block is modified and Increased iron absorption occurs. The explanation offered by Underwood (3) is as follows iron taken into the mucosal cell is converted to... 

Cross cell membranes very readily generally well absorbed from GIT in monogastric species penetrate into intracellular and transcellular fluids (e.g., synovial and prostatic fluids and bronchial secretions) also penetrate well into CSF, except tetracycbnes and rifampin termination of activity dependent on a high proportion of administered dose being metabobzed, for example, in the liver but also at other sites (e.g., kidney, enterocytes) some drugs actively secreted into bile... 

It is assumed that industrial amino acids obtained by chemical synthesis or fermentation are totally digestible in monogastric species. This corresponds to a value of 100% for standardised digestibility (SID) In the pig and true digestibility (TD) in poultry. However, this is not the case for the methionine hydroxy-analogue (see note 3). 

Rapeseed glucosinolates impair animal growth, but canola varieties are generally low in these compounds and thus more suitable as feed for monogastric species. Darroch et al. (1990) extruded canola screenings, a mixture of canola and weed seeds and chaff, with added ammonia. Ammoniation significantly reduced total glucosinolates, but residual ammonia levels may restrict this treatment for feeds only. 

TOXICITY. Copper is reiatively nontoxic to monogastric species, inciuding man. A FAOAVHO Expert Committee has stated that no deieterious effects in man may be expected from a copper intake of 0.5 mg/kg of body weight per day. Usuai diets in the United States rareiy suppiy more than 5 day. in order to provide for a margin of safety, the Nationai Academy of Sciences-Nationai Research Councii recommended copper intake for aduits is in the range of 1.5 to 3 mg/day. Daiiy intakes of more than 20 to 30 mg/day over extended periods wouid be expected to be unsafe. 

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