sc. G. Gebhardt

Untersuchungen zur Stickstoff- und Aminosäurenresorption im Dünndarm von wachsenden Schweinen

The amount of endogenous N in the chyme at the end of the small intestine and the amino acid composition of the ileum chyme were ascertained with growing pigs with ileorectostomy after feeding qualitatively differentiated protein sources. In dependence on the protein used, distinct differences turned out for some amino acids with regard to their content in the ileum chyme. Bacteriologic and histologic investigations subsequent to the dissection of the test animals showed that - in comparison to the control animals-the functions of the small intestine remained the same during the time of the experiment. The experiment method described appears to be suitable for absorption investigations up to the end of the small intestine of growing pigs.

Ergebnisse zur Wirksamkeit und zum Bedarf an ausgewählten Aminosäuren beim wachsenden weiblichen Schwein

On the basis of 87 N balance trials with growing female pigs the possibility of deriving lysine effectivity coefficients according to the difference method for proteins rich in lysine, based on proven additive relations for amino acid effectivity coefficients (Liebert et al., 1987b). The results from 9 proteins of various charges show that nutrition-physiologically relevant conclusions for lysine effectivity could be drawn under the conditions chosen. Thus the range of application of the chosen method of the registration of the effective amino acid quota in feed proteins could be significantly extended.

Untersuchungen zur Bestimmung der Aminosäurenbilanz des Magen-Darm-Traktes beim Hühnergeflügel

11 different feedstuffs (barley, wheat, rye, oat, wheat bran, soybean meal, peanut meal, cottonseed meal, rapeseed meal, horse bean, fish meal) were tested with adult colostomized broiler hens in digestion experiments; the digestibility of the crude protein and the amino acid (AA) balance of the gastro-intestinal tract were ascertained. The results achieved can be summarised as follows: The AA-composition in faecal protein is relatively independent of the AA-composition of the feedstuffs, it is not constant, however. The NPN-quota in faecal crude protein rises with the increasing crude fibre content in the feed. AA-digestibility calculated from the balance of the gastro-intestinal tract is, with the exception of some AA, in particularly the limiting ones, higher than the digestibility of the crude protein. As the AA-balance of the gastro-intestinal tract does not give a realistic picture of the digestibility of the AA, we recommend to ascertain the AA-balance up to the end of the small intestines in order to gain more profound knowledge with the help of such basic investigations with selected feedstuffs.

Beurteilung der Proteinqualität von silierten Maiskolben-produkten mit unterschiedlichen Rohfasergehalten

The assessment of the protein quality of silaged maize ear products was carried out on the basis of crude protein and amino acid analyses and of N balance measurings with growing pigs including comparative studies with maize corns and cereals. The differences found in the amino acid concentrations between the individual maize ear products could be verified on the basis of the analysed values of husks, cobs and corns. There were no significant differences in the parameters of total protein utilization (PNu, b-value) between the studied silages. The differing crude fibre content resulted, however, in reverse shifts in N excretion in faeces and urine, i.e. diminished protein digestibility was compensated by improved intermediary utilization.

Futterwert von Ackerbohnen für das Hühnergeflügel und Prüfung unterschiedlicher Anteile unter besonderer Berücksichtigung einer tanninärmeren Sorte im Broilermastfutter

The investigations were carried out with varieties rich in tannin (Erfordia, Fribo) and one poor in tannin (White Flowering). The protein of the variety poorer in tannin is slightly richer in methionine and is slightly better digested. The studies on the varieties Erfordia, Fribo and White Flowering in quotas of 7.5...45% as component in the fattening feed for broilers resulted in the same fattening performance as in the control group (maize-soybean-fishmeal ration) and had no influence on the chemical composition of the body and the weight of the pancreas. All rations were isonitrogenous and isocaloric. The soybean oilmeal in the ration was replaced gradually resp. completely by the field bean coarse meal in connection with methionine supplements. The variety poorer in tannin did not have nutrition-physiologic advantages in the the growth experiment with young broiler chickens.