Effects of l-carnitine via in ovo injection with or without l-carnitine feed supplementation on broiler hatchability and posthatch performance.

摘要

On d 18 of incubation, Ross x Ross 708 eggs were injected immediately before transfer with supplemental l-carnitine at concentrations of 8, 16, or 32 mg/100 micro L by using an automated multiegg injector. Three control groups (noninjected and injected with or without diluent) were also included. After hatching, 1,080 male and female broiler chicks were distributed into 90 pens of an experimental broiler house. Chicks hatched from eggs that were injected with l-carnitine at each of the 3 dosages received feed that was or was not supplemented with 50 ppm of l-carnitine, with the total number of treatments increased to 9 with 10 replicate pens per treatment during the grow-out phase of the experiment. None of the treatments had any effect on the incubation time or hatchability of fertilized eggs. At the end of the grow-out phase, birds that were fed supplemental l-carnitine and that had been injected with l-carnitine in ovo had lower BW and ate less feed. However, these same birds also exhibited a reduction in feed conversion when compared with birds that did not receive supplemental dietary l-carnitine. Livability was not affected at hatch or at 21 and 45 d posthatch by any of the experimental treatments. At processing, absolute and relative weights of the carcass, back half, and abdominal fat were found to be unaffected by any of the treatments. Breast meat yield was unaffected, but the absolute breast meat weight was reduced in birds given l-carnitine in ovo and in the feed. On the basis of the responses in feed consumption, final BW, and breast meat weight, supplementation of broiler diets with 50 ppm of l-carnitine appeared to reach toxic levels when provided with 8, 16, or 32 mg/100 micro L of l-carnitine administered via in ovo injection.Digital Object Identifier http://dx.doi.org/10.3382/japr.2010-00280