THE EFFECT OF ETHOXYQUIN ON TISSUE PEROXIDATION AND IMMUNE STATUS OF SINGLE COMB WHITE LEGHORN COCKERELS

The responses to supplementing the diet of Single Comb White Leghorn ( SCWL) cockerels with ethoxyquin were tested on two parameters: 1) tiss ue peroxidation and 2) immune response. In the first experiment, three concentrations of supplemental ethoxyquin (0, 500, and 1,000 ppm) wer e added to a basal diet and fed to SCWL cockerels for 6 wk. Tissue per oxidation was assessed by measuring the thiobarbituric acid reactive s ubstances (TEARS) concentration in the liver, kidney, heart, and splee n. The TEARS concentration in response to 500 ppm dietary ethoxyquin w as significantly lower in the liver and spleen tissues, whereas in the kidneys, 1,000 ppm ethoxyquin significantly lowered TEARS. In a secon d experiment, four concentrations of ethoxyquin (0, 125, 500, and 1,00 0 ppm) were added to a basal diet and fed to SCWL cockerels for 8 wk. The primary and secondary immune response were assessed by determining antibody titers to the Newcastle disease virus using hemagglutination inhibition (HI) and ELISA. The HI and ELISA titers for the primary an d secondary immune response were not significantly different from the control. Analysis of body weight, feed conversion, and organ weight re vealed no statistically significant differences between treatments, al though in the second experiment the dietary treatment of 1,000 ppm eth oxyquin resulted in significantly higher relative liver weight.