Abstract: The aim of this study was to probe into the effects of NPY gene on traits at first laying and egg production for Wenchang chickens in different energy diets. 600 Wenchang chickens were randomly divided into 3 groups: low energy( groupⅠ), middle energy (groupⅡ) and high energy (group Ⅲ) , with 5 replication in each group, each replication consisted of 40 chickens, their body weights were similar as treatment groupsThe polymorphism of NPY gene in Wenchang chicken was detected by using PCR- RFLP method. The results showed that three genotypes of AA, AB and BB were found. There were no significant difference on traits at first laying among different dietary energy levels and three genotypes(P＞0.05). The two increasing thrends of age at first laying and egg weight at first laying followed by the decline of dietary energy level were found.

Key words: NPY gene; traits at first laying; Wenchang chickens