A. Krogdahl et al., SOYBEAN PROTEINASE-INHIBITORS AFFECT INTESTINAL TRYPSIN ACTIVITIES AND AMINO-ACID DIGESTIBILITIES IN RAINBOW-TROUT (ONCORHYNCHUS-MYKISS), Comparative biochemistry and physiology. Part A, Physiology, 107(1), 1994, pp. 215-219
Rainbow trout (Oncorhynchus mykiss), 265 g kept in fresh water, 1 m(2)
surface area tanks, 10 kg per tank were fed diets based on high quali
ty fish meal added 0.00, 0.37, 0.74, 1.11 and 1.48% soybean proteinase
inhibitors, and chromic oxide as internal marker. After TO days, 10 f
ish were dissected to obtain total contents of intestinal segments, an
d faeces were stripped from the remainder. The inhibitors decreased pr
otein digestibility from 93 to 70%. Cysteine accumulated increasingly
in the small intestine with increasing dietary inhibitor level. A line
ar relationship between intestinal proteolytic activities and protein
digestibility was seen. Lipid digestibility was not significantly affe
cted.