本研究首先通过对产蛋前期（15周龄）和产蛋高峰期（30周龄）卢氏绿壳蛋鸡（LS）下丘脑比较转录组分析，鉴定差异表达基因（DEGs）；然后利用Gene Ontology (GO)富集分析，筛选DEGs中参与繁殖调控生物学过程（BP）的基因；进而通过蛋白质互作网络（PPI）分析，筛选调控繁殖过程的潜在核心候选基因（PCCGs）。在此基础上，利用qRT-PCR对PCCGs在两个地方鸡品种产蛋前期（15周龄）和产蛋高峰期（30周龄）下丘脑中表达水平的变化趋势进行分析，进而对基因表达量与30周龄产蛋数（EN30w）和血液繁殖激素水平的相关性分析，筛选影响地方鸡产蛋性能的关键基因；最后，从这些关键基因中筛选单核苷酸多态性位点（SNPs），并与不同时期产蛋数进行关联分析，进一步确定这些关键基因中影响产蛋的潜在SNP位点。产蛋前期和产蛋高峰期LS下丘脑比较转录组分析共鉴定出518个DEGs。对这些DEGs功能富集分析发现，10个BP中包含的64个DEGs可能通过神经内分泌过程参与鸡繁殖调控。进一步的PPI分析发现，64个DEGs中有16个高连接度（Degree≥12）的基因，即PCCGs。对这16个PCCGs在LS和固始鸡（GS）产蛋前期和产蛋高峰期下丘脑中的表达模式检测发现，其中的11个PCCGs在两品种两个时期下丘脑的表达水平差异显著（P<0.05），且变化趋势相同。在上述11个基因中，有8个基因的表达量与EN30w和血清生殖激素浓度呈显著相关（P<0.05）。8个基因中筛选的SNP位点与产蛋性状的关联分析表明，这8个基因与不同阶段的产蛋量存在显著相关（P<0.05），是调控地方鸡产蛋性能的关键基因。本研究鉴定出参与地方鸡产蛋调控的8个关键基因，包括CNR1、AP2M1、NRXN1、ANXA5、PENK、SLC1A2、SNAP25和TRH。这些发现为进一步理解鸡产蛋性能调控机制提供了新见解，并为地方鸡繁殖性能选育提供了可能的分子标记。

Beak trimming was a part of routine husbandry for poultry industry, which was the most efficient and economic way to reduce the incidence of cannibalism. However, the controversy about young chicken trimming still exits and it was drawing more concern recently along with the popular of animal behavior and welfare theory. To evaluate the influence of beak trimming on young chicken spleen development and find the key regulators of the spleen development, in this study, the electron microscope technique, flow cytometry and immunohistochemical techniques were used to investigate the effects of beak trimming stress on the spleen development. The result of electronic microscope showed that significant stress response could be found in chicken spleen cells after beak trimming. Cell volume became larger, chromatin of cell nuclear agglutinated conglobation, cytoplasm formed more vacuole, and mitochondria emerged vacuolization phenomenon in splenic lymphocyte after beak trimming. From the flow cytometry, the lymphocyte of spleen in the control group and experimental group were mainly in G1 phase, and the remaining small amount was in S and M phases. Of interest, the number of the lymphocyte which are in G1 phase within immune organ in the experimental group were more than that in the control group, but the number of cells in S and M phases were less than that in the control group. And beak trimming decreased the lymphocytes proliferation index of spleen. Inmmuohistochemical result showed that the beak trimming stress did not affect the expression sites of two apoptosis-related genes, Bcl-2 and Bax, in the spleen. But the expression level of Bcl-2 decreased while Bax increased in chicken immune organs after beak trimming. Furthermore, the beak trimming increased spleen cell apoptosis with a time-dependant style. Our findings may make a contribution to the active precaution of stress response.