The effects of dietary grape seed on antioxidant status in different plumage coloured Japanese quails exposed to heat stress

The aim of this study was to determine effects of grape seed supplementation to basal diet on antioxidant status of liver, kidney and heart in different plumage coloured Japanese Quails exposed heat stress. A total of 144 Japanese quails with different plumage colour at the age of 8 days old, 72 (36 females, 36 males) gray, 72 (36 females, 36 males) golden were used in this research. Birds were adapted to environment for a week. After, they were weighed and assigned to groups at the age of 15 days old. The birds were housed in heat stress (HS: 16h 34ºC, 8h 22ºC) and thermoneutral (TN: 24h 22ºC) conditions from 15 to 43. All birds fed with basal diet and basal diet supplemented with grape seed at both 100 ppm and 200 ppm doses (Control, GS100, GS200 groups, respectively). Diet and fresh water were offered ad libitum. Feed intake and body weight were determined at weekly intervals. The weight gain and feed conversion ratios of birds were then calculated. A total of six quails (3 males and 3 females) from each group were slaughtered after 43 days. Liver, kidney and heart were removed carefully for determine level of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-Px) and catalase (CAT). MDA levels of liver, kidney and heart tissues were increased in HS group compare with TN group (P 0.001). CAT activity of liver (P 0.001), SOD (P 0.01), GSH level (P 0.001), GSH-Px (P 0.001) and CAT (P 0.001) activities of kidney, GSH level (P 0.05), GSH-Px (P 0.001) and CAT (P 0.05) activities of heart were found significantly lower in HS group. Although MDA levels of liver (P 0.01) and kidney (P 0.001) were higher in golden group, heart MDA level was significantly lower (P 0.001). SOD and CAT activities (P 0.001) and GSH level (P 0.01) of liver were found higher in golden group. SOD activity of kidney was lower, GSH level and GSH-Px activity were higher in this group (P 0.001). SOD activity of heart was higher in grey group, on the other hand GSH level, GSH-Px and CAT activities were higher in golden group (P 0.001). Grape seed supplemented into diet significantly decreased MDA levels of liver, kidney and heart (P 0.001). Higher CAT activity of liver, SOD activity of kidney, GSH-Px and CAT activities of kidney and heart were obtained in control (no supplement) group (P 0.01). There were also significant interactions among main factors on MDA and antioxidant enzyme activities. It was concluded that higher thermal condition increased lipid peroxidation of the tissues and depressed antioxidant enzyme activity. Heat stress more affected to golden genotype than grey one. Grape seed supplementation played antioxidant role, especially 100 ppm dose possessed better potential.