|Cheng, Heng Wei|
Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/2/2007
Publication Date: 7/8/2007
Citation: Dennis, R.L., Fahey, A.G., Cheng, H. 2007. Different Effects of Individual Identification Systems on Chicken Well-Being [abstract]. Poultry Science Association Meeting Abstract. 86(1):362. Interpretive Summary:
Technical Abstract: Individual identification is a common method used in animal research. This study was designed to examine if various common identification systems, i.e., leg bands (LB), wing bands (WB), neck tags (ST), and livestock marker (LM), have different effects on hens' behavioral and physiological homeostasis. At 18 wk of age, hens were paired in all combinations of treatments and control (C, unmarked hens; n=10) in a novel cage for 5 trials of 1 hr each to test the effects of markers on social behaviors. Increased feather pecking (FP) was exhibited in WB hens compared with C hens (P<0.10) but not in LB, ST or LM hens (P>0.10). Increased FP in hens with WB may suggest an increase in social stress, and may lead to increased feather and body damage. No effect of identification treatment was evident on frequency of aggressive behaviors (P>0.10). At 20 wk of age, absolute fluctuating asymmetry (FA), but not relative FA, of shank length and width was more significant in LB hens (P<0.05), and tended to be significant in WB (P<0.10), but not in ST or LM hens, compared to C hens. Asymmetry of the shank is often a result of high stress levels, including social stress. Body weight (BW) measures at 20 wk showed hens with LB, but not WB, ST or LM, were significantly lighter than C hens (P<0.05), possibly as a result of decreased access to resources, increased metabolism or decreased appetite due to elevated stress. Increased FA and decreased BW are evidence of a disruption of the hens’ physiological homeostasis due to increased stress. Leg banded hens also tended to have lower percent heterophil (P<0.10), indicative of increased stress and reduced immunocompetence. Our findings provide clear evidence of the negative effects of WB and LB systems on hens’ well-being, altering both physiological and behavioral homeostasis, possibly leading to misinterpretation of experimental results.