For comparison of the reproductive organs and the egg quality in hens, a case study was undertaken on traditional Chinese Zhenning and commercial Hyline hen. A total of 15 hens from each breed were selected to study lipogenesis, serum lipids, and organ body weight ratios of liver, ovary and oviduct to compare their lipid synthesis and transportation mechanism. Moreover we also examined the histomorphological comparison of the egg forming organs and egg quality parameters between two breeds. Results showed significantly higher values of peroxisome proliferator-activated receptors gamma (PPAR γ), estrogen receptor alpha (ERα) and estrogen receptor beta (ER β) mRNA expressions in the liver of Zhenning than Hyline hen. Same difference was also observed in the vitellogenin (Vtg) protein levels. Triglyceride levels were higher in the Hyline hens. Besides this, liver, ovary and oviduct body weight ratio were significantly higher in Hyline hen than Zhenning hen. Moreover, Hyline hen had significantly higher oviduct weights. Ovary weight and hierarchy was also bigger in the Hyline hen. Finally, egg quality parameter comparison showed significantly lower values in the Zhenning eggs than the White Hyline eggs. These findings suggest that Hyline and Zhenning hen differ significantly due to selection in terms of lipogenesis, increase in body weight ratio of liver, ovary and oviduct morphology, while Hyline hens have also superior egg quality than Zhenning hen eggs.

Key words: Comparison, Domestic hens, Egg quality, Hyline, Ovary, Oviduct