Study of the utilization of light egg-type males: a proposal for the sustainability of the egg industry.

摘要

This study evaluated the performance and viability of light egg-type males, usually euthanized at the hatcheries, from White and Brown Leghorn laying hen lines. One-day-old male chicks, half from each hen line, were raised in floor pens until they were 42 d of age. The birds were distributed into 48 floor pens, furnished with tube feeders and nipple drinkers, and submitted to 24 h of continuous light, 3 feeding phases (1-7, 8-21, and 22-42 d) and diets composed of corn and soybean meal as the main ingredients. A completely randomized design was used in a 4 x 2 factorial arrangement (phase levels of ME dietary treatments x strain) of 6 replicates of 40 birds each. The variables evaluated were bird performance, carcass quality, and yield at 42 d of age. Mortality and cannibalism were not observed during the entire experimental period, although the birds' beaks were not trimmed. The brown males line showed higher feed consumption and BW gain and better feed conversion compared with the white male line (P< 0.05). Metabolizable energy (kcal/kg) levels of 3,200 (1 to 7 d), 3,050 (8 to 21 d), and 3,200 (22 to 42 d) provided better performance (P< 0.05) in both lines. The carcass yields were similar (P> 0.05) between the 2 lines; males from the white line showed higher breast yield, and the brown line males showed higher yield of thighs and drumstick (P< 0.05). The treatments had no effect on meat quality (P > 0.05). Overall, the results suggest that there is great viability for the use of male chicks from laying hens of both leghorn lines as a high quality protein source for human consumption.