Study On The Peproductive Performance Of Musco Ducks Supplemented With Quercetin

The purpose of this experiment was to study the effects of quercetin on the reproductive performance and egg quality of Muscogee ducks,and to provide a direction for improving the reproductive performance of Muscogee ducks and finding alternative additives.A total of 120 39-week-old white female muscody ducks and 24 male muscody ducks with healthy growth and normal laying were randomly divided into 4 groups with 3 replicates in each group and 10 ducks in each replicate.The experimental control group(basal diet)and experimental groups(basal diet +different concentrations of quercetin,in which quercetin supplemental levels in experimental groups were 0.02%,0.04% and 0.06%,respectively).The number of eggs laid in two months was recorded,and the fertilization rate and laying rate of eligible eggs were calculated.At week 0,4 and 8 of the experiment,the body weight of female ducks was weighed,and 2 females per replicate were killed,respectively.The serum was taken to measure the hormone concentration and antioxidant level,the weight of fallopian tube and ovary base were recorded,and the reproductive organ index was measured.At the end of week 8 of the experiment,duck eggs were collected and tested for egg quality within 24 hours.The results are as follows:After feeding for 1 to 2 weeks,laying rate in 0.02% quercetin supplemental group was significantly higher than that in control group,0.04% quercetin supplemental group and 0.06% quercetin supplemental group(P<0.05);There was no significant difference in laying rate between experimental groups and control groups at 3-4,5-6 and 7-8 weeks(P>0.05).The egg weight of groups supplemented with quercetin was significantly higher than that of control group(P<0.05);The yolk weight in 0.06% supplemental group was significantly higher than that in 0.02%supplemental group(P<0.05);Yolk height in 0.04% supplemental group was significantly higher than that in 0.02% supplemental group(P<0.05);The eggshell thickness of 0.04% and 0.06% supplemental groups was significantly higher than that of control group(P<0.05);The egg shape index of 0.06% supplemental group was significantly higher than that of control group(P<0.05);There were no significant differences in eggshell strength,average concentration height,Haugh unit and yolk diameter among all groups(P BBB 0 0.05).The fertilization rate of 0.04% and 0.06%supplemental groups was increased by 2.24% and 1.77% compared with the control group,but the difference was not significant(P>0.05).Compared with the control group,the hatching rate in 0.06% supplemental group was significantly increased by6.82%(P<0.05).At the 4th week of feeding,the fallopian tube index in 0.06% quercetin group and control group was significantly higher than that in 0.02% quercetin group(P<0.05);At the 8th week of feeding,the fallopian tube index in 0.06% quercetin group was significantly higher than that in control group(P<0.05).At the 8th week of quercetin feeding,the ovarian index of quercetin 0.04% and 0.06% groups was significantly higher than that of control group and 0.02% quercetin group(P<0.05).At the 4th week of feeding,there were no significant differences in the concentrations of LH,PRL,P and E2 between the groups supplemented with quercetin and the control group(P>0.05).There were no significant differences in the concentrations of LH,PRL,P and E2 among all groups at 8 weeks(P>0.05).There were no significant differences in serum MDA,SOD,T-AOC and GSH-Px antioxidant indexes between quercetin supplementation group and control group(P>0.05).At the 8th week of quercetin supplementation,SLC6A4 gene expression in hypothalamus of 0.06% quercetin supplementation group was significantly lower than that of control group and 0.04% quercetin supplementation group(P<0.05).SLC18A2 gene expression in 0.02% supplemental group was significantly lower than that in control group;There were no significant differences in the expression levels of TPH2,TH,DIO and TTR among all groups(P>0.05).There were no significant differences in the expression levels of PRL,GH,Gn RHR,GHRHR,COX-2,RLN3 and Cg A between pituitary groups supplemented with quercetin and control groups(P>0.05).Feeding proper amount of quercetin can significantly increase the eggshell thickness and the laying rate of muscody ducks.The gene expression analysis showed that quercetin could significantly reduce the expression levels of SLC6A4 and SLC18A2 in hypothalamus.