PROTEIN-QUALITY OF RAW SOYBEAN (GLYCINE-MAX), VIGNA (VIGNA-UNGUICULATA) AND CANAVALIA (CANAVALIA-GLADIATA) MEAL IN GROWING RATS

Thirty Sprague-Dawley rats from 45 to 50 g live weight and 21 days of age were used in a random block design (six rats per treatment) to eva luate the protein quality of three meals of raw legume grains: canaval ia (Canavalia gladiata), soya bean (Glycine max) and vigna (Vigna ungu iculata) in respect to casein and considering the albumin based diet a s the control of endogen secretions. The quality indices evaluated wer e: biological value (%), true digestibility(%), net protein utilizatio n (%), usable protein (%), protein efficiency rate and retained N in r espect to N consumed. Performance traits were also determined: initial live weight (g), final live weight (g), consumption (g animal(-1) day (-1)), average daily gain (g animal(-1) day(-1)) and feed conversion a nd the absolute weights (g), in relation to live weight (g/g) and to m etabolic weights (g/g(0.75)) of liver, pancreas, thymus and thyroid gl ands. No significant differences were found in animals consuming soya bean (biological value = 74.07, true digestibility = 82.93) in respect to the control. The animals consuming vigna (biological value = 57.05 , true digestibility = 70.21) were significantly different (P < 0.001) although the results were satisfactory. Only the liver weight diminis hed (P < 0.001) due to the consumption of both meals. The results were lower with canavalia (biological value = 52.74, true digestibility = 61.65) with lower liver weights (P < 0.001), thymus (P < 0.01) and thy roide (P < 0.01). The protein quality of raw soya bean and vigna was a dequate, but this did not hold true for canavalia, thus further studie s with the two former meals and new methods to raise the quality of th e latter are required.