Optimizing Feed Withdrawal in Broiler Effect of Feed Withdrawal Timing on Broiler Carcass Yield in Tropics

Food and for that matter poultry meat contamination has become a major concern to poultry producers, processors and consumers.The objectives of this study was to determine the optimum feed withdrawal time on broiler yield and provide basis formajor welfare problems in broiler destined for slaughter and processing.Two experiments were conducted.Experiment 1 was an on-farm data collection system based on typical feed withdrawal time practicedby a commercial farm on carcass yield.In experiment 2, Hubbard commercial day old chicks (n=200)were weighed and reared under anad-libitumfeeding and water condition for 56 days.At 56 days, broilers were randomly allocated to 5 feed withdrawal treatments (0, 4, 8, 12 and 16 hours) prior to slaughter.Parameters measured were the average feed intake and initial body weight, final live body weight, intestinal and crop weight, dressed weight and feed conversion ratio.All data were analyzed using the Generalized Linear Model ofSAS (Proc.GLM procedure)and lsmeans separated by SNK at P< 0.05.In experiment 1, a fixed 16 hour feed withdrawal period resulted in 267.5g live weight loss between before and after feed withdrawal.In experiment 2, the initial body weight and the feed intake was the same for all birds reared.The final live body weight, intestines and crop weight reduced significantly as the feed withdrawal time increased.The dressed weight of the 8, 12 and 16 hours was significantly (P<0.0001)lower than 0 and 4 hour withdrawal time.There was increased intestinal sloughing in 12 and 16 hours withdrawal treatment, indicating increasing poor welfare implications on the birds.Increasing length of feed withdrawal increased feed conversion ratio which was due heavily to live weight reduction as withdrawal time increased.While feed withdrawal has it benefits, the physical reduction in body weight, dressed weight and intestinal integrity pose a welfare danger to the birds in longer hours.