Effects Of Light Color On Growth Performance Of Cherry Valley Meat Duck

This experiment was conducted to determine the effects of different light color on growth performance,organ index,the antioxidant capacity,serum biochemical index,hormones and melatonin receptor gene expression in small intestine and microbial diversity of cecal chyme,in the 1～21 age Cherry Valley Ducks,the aim is to provide a reference for the setting of light conditions in the early stage of intensive cultivation of cherry valley meat ducks.Single factor randomized design was used in the experiment.One-day-old 300 male cherry valley meat ducks were randomly divided into five light groups,red light(631 nm),yellow light(586 nm),green light(518 nm),blue light(460 nm)and white light(380-780 nm)by using LED light.There were 6 replicates in each group and 10 ducks in each replicate,the experiment period was 21 days.The light intensity was 10 Lx at the height of ducks’ heads and scheduled for 24 h of light.This experiment studied the effects of light color on the growth performance of Cherry Valley meat ducks from 1 to 21 days,including terminal average weight,average daily feed intake,average daily gain,and feed/ gain ratio;the effect on the breast muscle rate,leg muscle rate,organ index,relative length of the intestine and relative weight of the intestine;effects of different light colors on plasma biochemical parameters of meat ducks,including glucose,total protein,albumin,globulin and albumin/ globulin ratio;effects on plasma lipid metabolism of meat ducks,including total cholesterol,total triglycerides,high-density lipoprotein And low density lipoprotein;effects of different light colors on plasma and liver antioxidant indexes of meat ducks,including catalase,total superoxide dismutase,glutathione peroxidase,total antioxidant capacity and malondialdehyde;effects of different light colors on plasma hormones and cytokines in meat ducks,including growth hormone,IGF-1,melatonin,leptin,adiponectin,insulin,IL-2,IL-6,TNF-α and IFN-γ;effects of different light colors on melatonin and its receptor gene expression in the small intestine of meat ducks;effects on microbial diversity of cecal chyme.Experimental results show that:(1)In the red and white light groups,the average end weight,average daily feed intake and average daily gain of cherry valley The blue light group had the lowest feed/gain ratio,the highest in the white light and red light groups,and was significantly higher than the blue light group(P<0.05),but there was no significant difference between the red light group and the yellow light and green light groups(P>0.05).(2)Different light colors had no significant effect on chest muscle rate and leg muscle rate of 1～21 day old Cherry Valley meat ducks(P>0.05).Different light colors had no significant effect on the heart,liver,kidney,thymus,spleen,bursa,gizzard and glandular stomach indexes of meat ducks(P>0.05).The pancreatic index of the white light group was significantly higher than that of other light color groups(P<0.05),different light color had no significant effect on intestinal relative length and intestinal relative weight of cherry valley meat ducks aged from 1～21 days(P>0.05).(3)Different light colors had no significant effect on plasma glucose,total protein,albumin,globulin and albumin/globulin of Cherry Valley Ducks aged from 1 ～ 21 days(P>0.05),There was no significant effect on plasma low density lipoprotein,high density lipoprotein and triglyceride(P>0.05),The content of triglyceride in plasma of white light group was significantly higher than that of red light group and blue light group(P<0.05).(4)Different light colors had no significant effect on plasma GSH-Px,MDA and T-SOD of 1～21 day old Cherry Valley meat ducks(P>0.05),the white light group CAT was significantly lower than the yellow light and green light group(P<0.05),the white light group T-AOC was significantly lower than the yellow,green and blue light groups(P<0.05).Different light colors have no significant effect on liver CAT and T-AOC of meat ducks(P>0.05),the white light group liver GSH-Px is significantly lower than the yellow,red and green groups(P<0.05),T-SOD was significantly lower than that of yellow light,green light and blue light group(P<0.05).White light group MDA is significantly lower than blue light group(P<0.05).(5)The content of plasma growth hormone was the lowest in blue light group,and there was no significant difference between blue light group and white light group(P>0.05).The plasma levels of IGF-1 and leptin in meat ducks in white light group were significantly higher than those in blue light group(P<0.05),The plasma levels of melatonin and adiponectin in cherry valley meat ducks in white light group were significantly lower than those in blue light group(P<0.05),there was no significant difference in plasma insulin content between white light group and blue light group(P>0.05).The plasma cytokines IL-2 and IL-6 of the white light group were significantly higher than the blue light group(P<0.05),there were no significant differences in TNF-α and IFN-γ between white light and blue light(P>0.05).(6)Different light colors did not significantly affect the melatonin content in the jejunum and ileum of 1～21 day old meat ducks(P>0.05),the content of melatonin in the duodenum of the red light group was significantly higher than that of other light color(P<0.05),the content of melatonin in the blue light group was the lowest,significantly lower than that in the white light group(P<0.05).There was no significant difference in the expression of melatonin receptor genes mel-1a,mel-1b and mel-1c in the duodenum and jejunum of meat ducks between the white light group and the blue light group(P>0.05),the Mel-1A and Mel-1C in the ileum of the white light were significantly higher than those of the other light color groups(P<0.05),The expressions of Mel-1A,Mel-1B and Mel-1C in the ileum of the white light group were significantly higher than those of the blue light group(P<0.05)..(7)The white light group increased the relative abundance of Bacteroides in the cecal chyme at various classification levels,and the blue light group increased the relative abundance of Alistipes.To sum up,under the conditions of this experiment,red light can promote the growth of meat ducks and the content of duodenal melatonin,and has no adverse effect on the plasma biochemical and antioxidant capacity of meat ducks.The growth performance of meat ducks in blue light group is the lowest,and the relative abundance of intestinal Alistipes is improved.