Nfluence of Preslaughter Fasting Hours on Gastrointestinal Tract Condition and Shrinkage

Abstract

This experiment was conducted in March 2007 to evaluate the effect of preslaughter fasting hours on broilers live body weight, live body weight shrinkage, hot carcass weight, dressing out percentage, feed consumption rate, gastrointestinal tract (GIT) content, GIT length, liver weight, and the economy of broiler production. In this experiment 120 chicks (ROSS 308) were used, the chicks were distributed in 20 pens, each pen contained six chicks. All birds were reared together with the same diet along the period of experiment, in the last day and before the slaughter time, the birds were weighed and distributed into four blocks according to their weight, each block divided to five treatment (0, 6, 12, 18, and 24) hours of fasting. At the end of fasting time all the birds were weighed again and the difference between the two weights was recorded (before and after fasting) as live weight shrinkage; after slaughtering, hot carcass weight, dressing out percentage, and gastrointestinal tract conditions were determined. The result of this study revealed that the live body weight of broilers after fasting, their live weight shrinkage, hot carcass weights, dressing out percentage, feed consumption rate, gastrointestinal tract (GIT) content and full crop weight were significantly (P≤0.05) affected by the fasting hours. While the live body weight, feed consumption rate, gastrointestinal tract (GIT) content and full crop weight were decreased by the increased of fasting hours. The live weight shrinkage and dressing out percentage was increased iv by the increased of fasting hours. The result of liver weight as affected by fasting hours also showed significant decrease with 24hr whereas the result of (GIT) length appeared to be significant unaffected with the exposure to the different preslaughter fasting hours. Hot carcass revealed the significant only in 6hr fasting