Submitted to: Poultry Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/11/2001
Publication Date: 9/1/2001
Citation: CHENG, H., DILLWORTH, G.A., SINGLETON, P.B., CHEN, Y., MUIR, W.M. EFFECT OF GENETIC SELECTION FOR PRODUCTIVITY AND LONGEVITY ON BLOOD CONCENTRATIONS OF SEROTONIN, CATECHALAMINE AND CORTICOSTERONE OF CHICKENS. JOURNAL OF POULTRY SCIENCE. 2001. V. 80. P. 1278-1285. Interpretive Summary: Cannibalism and aggression are major behavioral problems that cause suffering and death of birds and reduce income of poultry producers. Genetic selection has been shown to be a vital tool for overcoming the problems and improving birds' well-being. Present data showed that genetically selected birds with high or low group productivity and survivability differently altered regulation of their hormonal balance. The changes of hormonal levels were correlated to their coping abilities to domestic environments and displaying of well-being. These data suggest that the changes of blood concentrations of hormones can be used as indicators by producers and scientists to evaluate birds' well-being.
Technical Abstract: A line of White Leghorn birds selected for high group productivity and longevity resulted in reducing cannibalism and flightiness in multiple- bird cages. Improvements in survival may have been due to changes of physiological homeostasis. The objective of the present study was to test the hypothesis that genetic selection for high (HGPS) and low (LGPS) group productivity and survivability also alters regulations of neuroendocrine homeostasis. Blood concentrations of dopamine, epinephrine, norepinephrine, and serotonin were measured using a HPLC assay. Blood corticosterone levels were detected using a radioimmunoassay. LGPS birds had significantly higher blood concentrations of dopamine and epinephrine than the HGPS birds (P<0.01, respectively). The blood concentration of norepinephrine was not significantly different between the lines but the ratio of epinephrine to norepinephrine was higher in LGPS birds (P<0.01). The blood concentration of serotonin was also significantly higher in LGP birds compared to HGPS birds (P<0.01). In contrast, HGPS birds tended to have a higher level of blood corticosterone (1.87 +/- 0.19 vs. 1.49 +/- 0.21 ng/ml, P=0.08). The results suggest that selection for group productivity and survivability alters the bird's neuroendocrine homeostasis, which is correlated with bird's coping ability to domestic environments in the presently selected lines.