Untersuchungen zur präzäkalen Rohproteinverdaulichkeit und Aminosäurenresorption von Lupinen beim Schwein

Abstract

The apparent precaecal (pc) digestibility of crude protein (CP) and the apparent pc absorption of the key amino acids (AA) lysine, methionine, cystine, isoleucine, threonine and tryptophan from two yellow sweet lupine (L. luteus) varieties (Bornova, Borluta) and one narrow-leafed sweet lupine (L. angustifolius) were determined with ileorectostomized pigs. When the influence of the basal diet (barley or protein free rations) was checked with regard to absorption there were significant differences in a few cases only. In comparison to soybean meal (SBM) the methionine of the lupines was significantly worse, the cystine significantly better absorbed. The CP and the other key AA of the lupines showed approximately the same or even slightly higher pc absorption than those of SBM. With the example of the pc-absorbable AA amounts it was shown that sweet lupines with an approximately equally high CP content as in SBM cannot completely substitute the latter even after lysine and methionine supplementation because the absorbable tryptophan is by far insufficient, and isoleucine and threonine make up only 75% in comparison to SBM. On the basis of the content of pc-digestible CP and pc-absorbable AA it becomes possible to substitute high-grade imported protein concentrates according to their ability of AA supply in the feeding of pigs completely or partly by home-made protein feeds.

Assessment of ileal digestibility of lupin amino acids and their use in formulating diets for pigs

“…Although lupin seeds contain a high level of non-starch polysaccharides (NSP) (Gdala and Buraczewska, 1996), the apparent ileal digestibility of their crude protein was similar as in varieties tested by Wiinsche et al (1990) amounting to 85% on an average and was as high as that of soyabean meal. The physiological effects of the NSP depend, however, on their composition and physico-chemical properties (Gdala, 1998).…”