Effects of different cage sizes and nest settings on laying hen nesting behavior and the proportion of dirty eggs in furnished cages

Furnished cages may promote laying hen welfare more than the traditional cage, but the high proportion of dirty eggs in the furnished cage system could directly affect the exterior quality of eggs, reducing the economic advantage of the furnished cage production system. The problem of the high proportion of dirty eggs reveals defects in the design of the cage, and it may also indicate competition among hens, affecting the utilization of nests. The research aimed to examine the effects of cage size, nest location, and degree of enclosure on behavioral adaptation and the proportion of dirty eggs. Nine hundred laying hens (Hy-line Brown) were housed in cages with eight different types of nests, and the experiment began at the 18 weeks of age and ended at week 38. The proportion of dirty eggs and the nesting behavior of hens were recorded. The number of nest visits and the sitting behavior of the hens in the medium furnished cage were significantly higher than in the large furnished cage (visits: P < 0.01; sitting: P < 0.01). The number of nest visits in the higher nests was significantly greater to lower nests (P = 0.01). The number of nest visits in the enclosed type nests was significantly higher than in the open type nests (P = 0.01). The cage size, nest location, and amount of enclosure had no significant effect on the proportion of dirty eggs (P > 0.05). In conclusion, the enclosed nests in a higher location were more attractive for laying hens.