Lysine plays a central role in poultry nutrition as the reference amino acid for the ideal protein ratio. While its requirements are well defined in broilers, information for current turkey strains, particularly during early development, is limited. Most turkey data originate from studies conducted in the mid-1900s to early-2000s and may not accurately reflect the needs of current genetic strains. Therefore, this study aimed to determine the digestible lysine (dLys) requirement of Nicholas Select male poults sourced from young breeder hens in the second week of lay from d 0-28. Six diets varying in dLys were formulated to determine the influence on feed intake (FI), live weight gain (LWG), body weight (BW), dLys intake, and mortality-corrected feed conversion ratio (FCRm). Poults were sourced from young breeder hens, which typically produce lighter poults at hatch. Such poults often begin life at a disadvantage due to lower initial nutrient reserves and may require greater nutritional support to achieve optimal growth. Optimal performance was observed between 1.79 and 1.96% dLys, while higher dLys levels did not provide additional benefits. Quadratic polynomial regression revealed a requirement of 1.84% dLys. Overall, the findings indicate that poults originating from young hens in the second week of lay may have higher dLys requirements than previously reported. Establishing updated amino acid recommendations for young turkeys is critical for supporting early growth, and improving feed utilization derived from breeder hens of varying ages.
Boontarue et al. (Wed,) studied this question.