Effects of supplying time of prestarter on subsequent broiler performance, carcass yield and intestinal morphometry

详细

The study was conducted to evaluate the effects on subsequent performance, carcass traits, jejunal histomorphology for broilers subjected to various time of feeding prestarter diet. For this purpose three hundreds day old Cobb 500 chickens were used. Chickens were grouped as a completely randomized design with 4 treatments and 4 replications. Prestarter diet was fed to 4, 6, 8 or 10 days of age. Starter diet was fed for variable times depending upon termination of feeding prestarter. Finisher diet was fed beginning at 22 days of age. Diets were identical in terms of all the nutrients levels. Morphometric indices of jejunum were measured at 10 days of age and the end of the production period. Increasing the duration of feeding prestarter diet significantly increased body weight and decreased FCR at 10 days of age (P < 0.05). However, treatments' effect on final BW was not significant (P > 0.05). The FCR of birds fed the prestarter for 10 days significantly lower from that of birds fed the prestarter for 4 days at the end of experiment (P < 0.05). The time of feeding prestarter diet had no significant effect on feed intake (P > 0.05). There was no significant effect of time of prestarter diet on dressing percentage, breast meat, legs or wings weight (P > 0.05). Different feeding strategies had significant effect on intestinal histomorphology (P < 0.05). Birds fed prestarter diet for the first 10 days had higher villi width and villus surface area (VSA) compared with other treatments at 10 days of age. Based on the data under the experimental conditions, the optimum time of feeding prestarter diet for birds grown to a target weight of approximately 2.2 kg appears to be 10 days.