Evaluation of the hatchery by-product meal as feedstuff for laying hens

Abstract

Hatchery by-product- meal was evaluated through a laboratory test and also a trial with laving hen. In the first trial, the chemical composition was determined in five samples of the processed and seven non processed wastes from several origins. The protein digestibility was determined in waste samples collected before and after the industrial processing and treated at laboratory, with temperatures of 60°C, 80°C, 100°C, 120°C or 140°C, during two hours. The chemical composition of the waste samples was variable, and the mean results encountered characterize them as a protein source with high calcium and low phosphorus levels. The protein digestibility decreased as the temperature increased, with a significant reduction at 140 °C. In the second trial, the performance of the laying hens was measured, between the 29th and the 44th week of age. A split-plot randomized experimental design with five treatments and 16 replications per treatment was utilized considering each bird as one experimental unit. Statistical differences between treatments (P> 0.05) were not observed for feed consumption, egg production, egg weight, feed conversion and shell thickness. Specific gravity was significantly (P<0.05) reduced in the group of hens where 100% of the calcium requeriments was supplied by hatchery by-product.