Digestible Lysine Requirements of Male Turkeys During the 6 to 12 Week Period

Abstract

Two floor pen trials were conducted using Nicholas White male turkeys in order to determine the digestible lysine requirements for the 49 to 61 day and the 72 to 83 day feeding periods. Prior to the study, birds were fed a typical corn, soybean meal (SBM) and pork meal based diet. They were then weighed and sorted into 48 floor pens in a curtain-sided building. Dietary treatments included eight levels of digestible lysine ranging from 0.88 to 1.23% in the first trial and 0.68 to 0.96% in the second trial. A high protein positive control treatment was added at the expense of three replicates of the highest lysine level. The lysine deficient basal diet was corn, SBM and pork meal with an intact crude protein level of 18.4% in the first experiment and 15% in the second experiment. The positive control diet was also corn, SBM and pork meal and was formulated on a total AA basis to meet nutrient requirements set by the NRC (1994). Lysine-HCL (98.5%) was used for the titration and glutamic acid was titrated inversely to maintain nitrogen at similar levels. The experiments were set up as a randomized complete block. Splined regression analysis determined the digestible lysine requirement for the 49 to 61 day period to be 1.09% for optimum bodyweight gain and 1.11% for feed conversion. The digestible lysine requirement for the 72 to 83 day period was 0.87 and 0.86% for optimum body weight gain and feed conversion, respectively.