Changes in Egg Production, Egg Quality, Blood and Egg Cholesterol Levels with Age in Layer Hen

Abstract

This study aims to investigate the changes in egg production, quality, and blood, and egg cholesterol levels with age and examine the relationship between these parameters. In this context, a total of 340 eggs were used obtained from 34-53 weeks-old Brown Nick layer hens. In the experiment, egg weight and egg production were daily, egg quality and cholesterol level was weekly measured for 20 weeks. The serum cholesterol level was determined at 34, 42 and 53 weeks. According to the research results, live weight, average egg weight, weekly total egg weight and weekly egg cholesterol level increased with age. Whereas the number of weekly eggs per animal was low at the beginning, it increased towards the middle and decreased towards the end of the experiment. Among the quality parameters, yolk weight, shell weight, shell breaking strength, average shell thickness, yolk index, L and a* value of yolk color, number of blood and flesh stains were affected by increasing age, whereas albumen weight, albumen index, Haugh Unit, shape index and yolk color b* value was unaffected. And the changes in serum and egg cholesterol levels were not significant at 34, 42 and 53 weeks. On the other hand, there was a significant relationship between egg yolk weight and egg yolk cholesterol and between egg weight and egg yolk weight. The results show that egg quality traits changed with age. It is necessary to focus on new studies to improve the internal and external quality of eggs in order to extend the holding period of commercial flocks and thus increase the operating profit.