http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
effects of pullet body weight on subsequent laying hen performance
Two experiments were conducted with commercial egg-type laying hens to determine the effects of housing body weight and parental egg weight on egg quality and laying hen performance. In experiment 1, egg production improved significantly as housing body weight increased from 1000 g to 1599 g. Once the housing body weight surpassed the threshold of 1599 g, a significant reduction in hen-day egg production was observed. The only significant difference in feed conversions which could be associated with housing body weight was observed in the largest hens which was significantly higher. Egg weights and egg shell weights increased significantly as housing body weights increased while percent shell and specific gravity were not affected by body weights. In experiment 2, commercial hatching eggs were obtained, grouped and incubated in one of three groups according to egg weight. It was determined that egg size does affect chick hatching weight with the advantage in weight being maintained throughout the growing and laying periods. Hen-day egg production, egg weight and egg shell quality as measured by shell weight, percent egg shell, shell thickness and specific gravity were not significantly affected by parental egg weight.
Includes bibliographical references (leaves 29-30).