Physiologic nutrition studies in swine with ileorectal anastomoses. 2. The effect of nourseothricin on nutrient digestibility, amino acid absorption, protein utilization and mineral balance of a rye diet

The supplement of nourseothricin (NT) to a rye diet did not have an influence on the precaecal and total apparent digestibility of the crude nutrients or the total digestibility of the amino acids (AA). NT produced significantly higher absorption of some AA in pigs with ileo-rectal anastomoses (IRA) which were orally supplied with electrolyte solution (ES). In general, IRA pigs showed the same results with regard to precaecal apparent AA absorption influenced by the AA pattern of endogenous protein as pigs with ileal cannulae. Functions in the large intestine seem to be important for the effect of NT supplements, as NT supplements to the diet of intact animals tendentially had a positive effect on N, Ca and P balances, IRA animals, however, showed a contrary effect. In comparison with the intracaecal infusion of ES, the oral supply of the IRA pigs resulted in higher N, Ca and P balances. The level of N utilization (N balance in % of the digested N) of the IRA pigs supplied orally was equally high as that of the intact animals (both groups without NT). As derives from literature and the available N, Ca and P balances--significantly influenced by ES supplements--an additional supplement of rations poor in crude fibres of 1 g Na/animal and day seems sufficient for covering the requirement of IRA pigs of a weight of 30...40 kg. After 18 days a P supply below the requirement resulted in a significantly reduced P level (inorganic) in the serum in both animal groups, with the level of the IRA pigs being significantly below that of the INT animals. For this reason, the P requirement of fattening pigs should be fully covered in experiments with IRA pigs. Although the IRA pigs supplied caecally with ES showed typical appearances of Na deficiency, their Na level in the serum did not differ from that of the other animals.