富集型蛋鸡笼设计旨在改善产蛋鸡的福利状况，并继承传统鸡笼较高的生产性能和健康水平。特别是大型富集笼的产生对提高蛋鸡福利方面大为改善，然而因富集笼内鸡群规模的增大，问题也相继产生，这主要与群体中个体的社会竞争有关，因此在大型富集笼设计改造时，应该充分考虑蛋鸡群体社会性因素的影响。以往的研究仅局限于社会性对资源配置的影响，而富集笼环境下蛋鸡群体的社会性基本特征(如社会结构)尚不清楚，因此在富集笼设计工艺改进方面还没有可遵循的理论基础。针对这一理论不足，本研究首次提出蛋鸡群体“社会竞争指数”来确定个体在群体中的社会地位，为构建群体的社会优势等级提供了条件。在此基础上,进一步研究群体大小、资源丰富度对蛋鸡社会结构所产生的修饰作用以及该修饰作用对蛋鸡资源占有效率及蛋鸡的生产性能所产生的影响，为改进大型富集鸡笼设计提供理论依据。

The emerge of enriched cages aims to improve laying hens welfare state and keeps the advantage of the conventional cages in productivity and health conditions of laying hens. Especially, large enriched cages design to further enhance the welfare status of laying hens compared with a small enriched cage, however, some problems also emerge with the large enriched cages due to social competition among hens occurs. Therefore, to tackle the problems when we modify the design of the large enriched cages, the effects of social competition should be considered. The previous studies on the enriched cages mainly focused on the effects of availability of resources on production or utility of these resources, but social structure of the hens is still not clear. The purpose of this project aims to give a new concept: “Social Competition Index, ISCR” in order to determine social ranking of an individual in a group, and based each hen’s ISCR, we con classify them in each social order class. Then, we further investigate the modification of group size and availability of resources on Social Order Class of individuals, and their effects on production level and resource distribution. The result of this will provide.theoretical evidences for proper re-design of the large enriched cages.