Mehran  Mehri, Ali-Akbar  Davarpanah, Ghasem  Jalilvand, Gholam-Reza  Zaboli, 
    Estimation of Standardized Ileal Digestible Lysine Requirement of Starting Broiler Chicks Fed Soybean-and Cottonseed Meal-Based Diets,
    Journal of Animal and Veterinary Advances,
    Volume 10,Issue 10,
    2011,
    Pages 1278-1282,
    ISSN 1680-5593,
    javaa.2011.1278.1282,
    (https://makhillpublications.co/view-article.php?doi=javaa.2011.1278.1282)
    Abstract: The research was conducted to determine the Standardized Ileal Digestible Lysine (SID Lys) requirement of male broiler chicks from 0-14 days of age and to study the carry-over effects of early Lys deficiency in growing chickens. In the starter, graded levels of SID Lys in the experimental diets were achieved by addition of Lysine-HCl at the expense of cornstarch obtaining dietary SID Lys ranging from 0.88-1.28% of diet. Linear regression analysis was significant (p<0.05) for Body Weight Gain (BWG), Feed Intake (FI), Breast Meat (BM) and Thigh Yield (THG) to dietary Lys. Both of Linear Broken-Line (LBL) and Quadratic Broken-Line (QBL) models were fitted to determine SID Lys requirement. Regarding response criteria and regression models, SID Lys requirements of starting broiler chicks were from 1.06-1.29% of diet. Assuming 83% lysine digestibility of basal diet, the requirements were 1.28-1.55% of diet on total amino acids basis which were much higher than NRC recommendations. From 14-28 days of age, chickens were fed common grower diet according to NRC. Linear regression analysis was significant for BWG, Feed:Gain (FG), BM and TGH yield (p<0.05). Early lysine deficiency significantly reduced BWG, feed efficiency, BM and TGH yield (p<0.05). This study clearly showed that the very lysine-deficient fed chickens could not mount a compensatory growth.
    Keywords: India;lysine-deficient;compensatory growth;broiler chicks;modeling;Lysine