Immune Response In Laying Hens Research Articles

PSXIII-5 Effects of Stocking Density on the Welfare and Immune Responses of Laying Hens Housed in Small Furnished Cages

Abstract To investigate the effects of stocking density on the welfare and immune responses of laying hens housed in furnished cages, 192 Hy-Line Brown hens were housed in small furnished cages and randomly divided into three groups on their 18 weeks old for low-density group (833 cm2 per hen, LD), medium-density group (625 cm2 per hen, MD), and high-density group (500 cm2 per hen, HD). There are eight cages in each stocking density. The welfare of laying hens was assessed at 22, 42 and 72 weeks of age (WOA) for feather quality, foot cleanness, footpad dermatitis, hyperkeratosis and keel bone damage. After the last welfare assessment, venous blood from the wing of the hen was extracted for testing immune indicators of Immunoglobulin Y (Ig Y), Interferon gamma (IFN-γ), Transforming growth factor beta (TGF-β), Interleukin-2 (IL-2), Interleukin-4 (IL-4), Interleukin-6 (IL-6), Interleukin-12 (IL-12) by enzyme-linked immunosorbent assay (ELISA). Results showed that feather quality of laying hens from HD group was worse than hens from LD and MD groups at 42 and 62 WOA (P < 0.05). The foot cleanness score of hens from HD group was worse than other two group hens at 62 WOA (P < 0.05), respectively. There was no significant difference between three groups on other welfare indicators (P > 0.05), but the welfare quality of laying hens got worse with the aging of laying hens. Laying hens from LD group had greater concentrations of serum IFN-γ, IL-2, IL-6 compared with hens from MD and HD groups (P < 0.05). There was no significant difference for other immune responses (P > 0.05). These findings suggest that keeping a high stocking density of laying hens could cause feather damage, impact the welfare quality and reduce the immune responses of laying hens housed in small furnished cages.

Immune Response of Laying Hens Exposed to 30 ppm Ammonia for 25 Weeks

Immune Response of Laying Hens Exposed to 30 ppm Ammonia for 25 Weeks

The Effects of Different Levels Chlorell Microalgae on Performance and Immune Response of Laying Hens Under Heat Stress Condition

This study was conducted to determine the effects of different levels microalgae Chlorell sp. on performance of laying hens under heat stress condition. A completely randomized design experiment, with 7 replicates and 6 treatments (9 birds per replicate) was carried out by allotting 378 white Lohman strain laying hens at 65 weeks of age. Six experimental treatments were continual addition of 0, 100, 200, 300,400 ppm microalgae Chlorell and 400 ppm toein to drinking warer were fed to laying hens for 9 weeks. Egg production, egg weight, egg mass output and feed intake were determined. Antibody production against sheep red blood cells (SRBC) also was measured. Data were analyzed by ANOVA using General Linear Models procedure of SAS software and comparison of means were compared using Duncan’s multiple range test. The results of this experiment showed that microalgae Chlorell had no effect on productive performance. Adding microalgae Chlorell to the drinking water improved immune response of laying hens and a more positive effect was observed when 400 ppm added to the water. It is concluded that the addition of microalgae Chlorell to the water drinking of laying hens improved immune response of laying hens.DOI: http://dx.doi.org/10.3126/ijls.v9i2.12058 International Journal of Life Sciences 9 (2) : 2015; 71-74