Location: Livestock Behavior ResearchTitle: The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens Author
|Tucker, Christina Marie|
|Cheng, Heng Wei|
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/26/2016
Publication Date: 3/31/2017
Citation: Wu, Y., Yan, F., Hu, J., Chen, H., Tucker, C., Green, A.R., Cheng, H. 2017. The effect of chronic ammonia exposure on acute phase proteins, immunoglobulin and cytokines in laying hens. Poultry Science. 96:1524–1530.doi.org/10.3382/ps/pew454. Interpretive Summary: Ammonia is a potential health hazard to farm animals at a level higher than 25 ppm. This study was to examine long-term effect of ammonia at 30 ppm on health status in laying hens. The results showed that the most currently measured immune parameters did not significantly change between ammonia exposed hens and control hens although the levels of certain inflammatory markers were higher in ammonia exposed hens. These results indicated that hens may have the capability to adapt or tolerate to ammonia caused chronic stimulation. These results could be used by producers and scientists for conducting further investigation and developing management guidelines for improving hen well-being.
Technical Abstract: Ammonia is a potential health hazard to both humans and animals, causing systemic low-grade inflammation based on its levels and durations. The objective of this study was to examine the effect of 45 weeks of exposure to 30 ppm NH3 on the concentrations of acute phase proteins, immunoglobulins and cytokines in laying hens. At 18 weeks of age, a group of commercial hens were randomly assigned to 4-hen cages. These cages were evenly divided between 2 environmentally controlled chambers. At 25 weeks of age, one chamber was maintained continuously with fresh air (NH3 < 5 ppm; control group) and the other one was injected with NH3 and controlled at 30 ppm (NH3 group) for 45 weeks. At 70 weeks of age, blood and spleen samples (n=8 per treatment) were collected for analyses of physiological and immunological parameters. No significant differences were observed in plasma albumin, complement components (C)-3 and C-4, immunoglobulin (Ig)M, IgA and IgG, interleukin (IL)-6, IL-10, interferon gamma levels in the NH3 group compared to controls. Compared to controls, NH3 exposed hens had higher plasma levels of a-1-Acid glycoprotein (24%) and tumor necrosis factor alpha (54%) and higher mRNA expression of IL-1ß (47%) and IL-6 (62.5%) in the spleen. These results indicated that hens may have the capability to adapt or tolerate to moderate (30 ppm ammonia)chronic stimulation. Future studies should explore acute effects of NH3 at higher levels on hen health and welfare.