The Fatty Acid Profile And Expression Of PPAR?,FADS2 And ME1 In Chinese Wanxi White Geese During Fattening

The fatty acid profile of muscles is an important indexes for evaluating meat quality.In this study,breast and leg muscle fatty acid(FA)profile and the mRNA expression levels of PPAR?,FADS2 and ME1 gene in muscles and liver of Chinese Wanxi White geese during fattening period was measured.The fattening period was stared at 70 d for thirty days.In the first experiment,sixty geese with similar body weight were selected with 3 replicates and 20 per replicate.In the second experiment,two hundred and forty geese were divided into four groups with 3 replicates in each group and 20 per replicate.A supplementary green forage of 0%,15%,30% and 45%(relative to dry matter)were provided to geese in each group,respectively.Five geese were randomly selected from each replicate for breast,leg muscle and liver sampling at 0,10,20,and 30 d of fattening period.Gas chromatography was used for fatty acid determination and qPCR was used for gene expression detection.1.The content of intramuscular fat in breast was 2.04%,significantly higher than that of leg muscle(P<0.0001).2.The content of C16:0in breast muscle was 22.04%,significantly higher than that of leg muscle(P<0.0001)while C18:2(18.28%),C16: 1(1.26%)and C18:1(25.38%)was significantly lower than that of leg muscle(P<0.0001,P=0.043,P=0.051).The content of SFA in breast was 39.43%,which significantly higher than that of leg muscle(P<0.0001),while UFA/SFA(1.47),MUFA(26.65%)and PUFA(30.84%)was significantly lower than that of leg muscle(P<0.0001,P=0.044,P=0.017).The content of C18:0,C18:3 and C20:3exhibited no significant difference between breast and leg muscle.3.The content of C16:1 C18:2 and UFA/SFA increased and C18:0 and SFA decreased during fattening period.The content of C16:0,C18:1,C18:3,C20:3,MUFA and PUFA exhibited no significant changes during fattening period.4.The mRNA expression of PPAR? in liver exhibited highest at 90 d and lowest at100 d(0.38,P<0.0001),while FADS2 was highest at 80 d(3.27,P=0.009)and ME1 expressed lowest at 100 d(0.43,P=0.010).The mRNA expression of PPAR? in leg muscle exhibited highest at 90 d(2.01)and lowest at 100 d(0.93,P=0.040)while FADS2 and ME1 exhibited no significant changes.There was no significant expression difference of the three genes in breast muscle.5.Green forage addition exhibited no effect on intramuscular fat content.However,the content of C18:0 and C18:3 in leg muscle(P=0.035,P=0.001)exhibited significant difference with green forage addition.The content of C18:0 increased with supplementation of green forage,and the content of C18:3 decreased with supplementation of green forage.The content of C18:3 in breast muscle increased with supplementary green forage and reached highest level in geese supplemented with 45% green forage(0.44%,P=0.017).The expression of FADS2 and ME1 in liver were lower in geese supplemented with 15%,30%,45% green forage as compared to control group(P=0.025,P=0.001).6.The expression of PPAR? increasing associated with C16:1,C18:3 and UFA/SFA content increase(P=0.004,P=0.004,P=0.021),while the content of SFA decrease(P=0.016).The expression of FADS2 increasing associated with C16:1,C18:1,C18:3,MUFA and UFA/SFA content increase(P<0.0001,P=0.016,P=0.002,P=0.009,P=0.030),while SFA and PUFA decrease(P=0.046,P=0.040).The expression of ME1 increasing associated with C16:1,C18:1,C18:3,MUFA and UFA/SFA increase(P<0.0001,P=0.002,P=0.001,P=0.001,P<0.0001),while C18:0,C20:3 and SFA decrease(P=0.007,P=0.046,P<0.0001).The mRNA expression of PPAR?,FADS2 and ME1 was significantly associated with fatty acid content in Chinese Wanxi White geese,suggested that these genes might be used as candidate genes for fatty acid selection in geese breeding.