Reza Akbari Moghaddam Kakhki - Department of Animal Science, Ferdowsi University of Mashhad
Abolghassem Golian - Department of Animal Science, Ferdowsi University of Mashhad
Heydar Zarghi - Department of Animal Science, Ferdowsi University of Mashhad

A total of 240 Hy-line W-36 hens were allocated to five treatments and six replicates of eight each to evaluate the effects of different levels of digestible sulfur amino acid (DSAA) on egg quality, component yield and composition during 32 to 44 week of age. This experiment was conducted in a completely randomized block design. The treatments were included five levels of DSAA as 5.1, 5.6, 6.1, 6.6 and 7.1 (g / kg). Blocks did not have any significant effect on all measured parameters. An increase in DSAA intake from 496 to 672 (mg/b/d) significantly enhanced egg weight from 57.97 to 62.55 g. An increase in DSAA intake did not have a significant effect on haugh unit, percentage of egg components, specific gravity, eggshell thickness, dry matter and protein constituents of eggs. Although, haugh unit was quadratically related to dietary DSAA. Based on the broken-line regression analysis, the DSAA requirement for optimal egg weight and haugh unit were 653 and 693 (mg/b/d), respectively.

Digestible sulfur amino acid, Egg quality, Egg components yield, Egg protein