EFFECTS OF MELATONIN ADMINISTRATION ON THE PHYSICAL PROPERTIES OF EGG SHELL AND INTERNAL EGG QUALITY IN LAYING HENS DURING THE HOT- DRY SEASON

Résumé

Poor egg shell quality and poor internal egg quality as a result of heat stress are detrimental to poultry egg industry. The aim of the present study was to determine the influence of melatonin administration on egg shell properties and some internal egg quality traits of laying hens during the hot-dry season in the Northern Guinea Savannah zone of Nigeria. Birds were divided into 2 groups of melatonin-treated (0.5 mg/kg) and control. Egg, shell, egg content, albumin and yolk weights were examined. Total egg weight, egg content weight, albumin weight and yolk weight in both groups were not significantly different (P > 0.05). Conversely, the egg shell weight was significantly greater in the control group than in hens treated with melatonin (P<0.001). In conclusion, melatonin supplementation may, be better-suited in birds raised for meat rather than in those for egg production.