Effects of genotype, age and their interaction on egg quality in brown-egg laying hens.

摘要

The experiment was conducted to compare the effects of strain and age on egg quality characteristics of ISA Brown, Hisex Brown and Moravia BSL brown-egg laying hens. 108 ISA Brown hens, 45 Hisex Brown and 45 Moravia BSL, 20-60 weeks old, were housed in conventional cages (550 cm2 per hen). Feed and water were available ad libitum. Eggs were sampled at 21-day intervals, every collecting week 150 eggs per genotype in three age periods, from 20 to 26 weeks, 37 to 43 weeks and 54 to 60 weeks of age. A total of 4050 eggs were examined. Egg quality characteristics were affected by genotype and age. Results revealed that the egg weight, yolk weight and percentage, Haugh Units increased with the hens' age in all genotypes, but albumen and eggshell percentage decreased, eggshell thickness and strength improved with age. The highest egg weight (65.3 g) and yolk quality (yolk index 45.1%) were found in Moravia BSL at the end of the experiment. The best albumen quality (albumen percentage 60.0) values were found in Hisex Brown and the eggshell quality measurements (eggshell thickness 0.38 mm) were higher in ISA Brown.