The Effect of Lighting, Dietary Amino Acids, and Litter on the Incidence of Leg Abnormalities and Performance of Turkey Toms

Abstract

Two trials were conducted to determine the effect of light duration on the incidence of leg abnormalities and related parameters in turkey toms. A step-up lighting program was compared with a step-down regimen in which intensity was maintained at 2.5 lx for both programs. In addition to lighting, Trial 1 evaluated the effect of reduced dietary lysine and methionine plus cystine levels during the starter and grower periods, and Trial 2 investigated the effects of type (pine shavings vs. whole rice hulls) and depth (5 cm vs. 10 cm) of litter. For both trials, toms reared in the low intensity step-up lighting program had reduced body weights, poorer feed to gain ratios, consumed less feed, and were more active when compared with toms raised in the low intensity step-down lighting program. The incidence of leg abnormalities was unaffected by lighting (Trials 1 and 2), diet (Trial 1), or type and depth of litter (Trial 2). For toms of the step-up lighting program, the absolute length of the left tarsometatarsal bone was shorter, but when expressed on a ratio to body weight, the relative length was longer. Testes weights were larger in Trial 2 for toms of the step-up lighting program as compared with toms of the step-down lighting regimen with no differences due to lighting in Trial 1. Toms fed the reduced amino acid rations in Trial 1 showed reduced body weight at 84 days of age when compared with controls; at all other ages there were no differences between dietary treatments. Type and depth of litter did not affect the performance of turkey toms.