Protein quality of two cultivars of lupin seeds evaluated in weanling rats

For 3 weeks, 128 male Sprague-Dawley rats, 3 weeks old, were fed on diets containing no protein, casein, soyabean meal, roasted or raw soyabeans, or sweet white lupin (Lupinus albus) cultivar Primorski or Ultra without or with 0.1% lysine or 0.2% methionine. Relative net protein ratio (RNPR) (casein = 100%) of lupins Primorski and Ultra supplemented with methionine was 81.1 and 79.1%, respectively, and was higher than that for roasted soyabeans (71.4%) (P<0.05) and similar to that of soyabean meal (83.1%). Supplementation of lupins with lysine improved (P<0.05) RNPR of Ultra (88.0%), but not that of Primorski (81.9%). RNPR values of soyabean meal, Ultra or Primorski supplemented with lysine and methionine were not different..