Effects Of Dietary Supplement With Phy-Sterol Esters On Production Performance,Egg Quality And Serum Biochemical Indexes Of Quail

Synthesis of Phytosterol esters（PSE）by esterification and transesterification of phytosterols and fatty acids,which can be converted into sterols and fatty acids in the body.The physiological functions of PSE were similar with phytosterols and fatty acids.Moreover,PSE have higher biological than phytosterols in some aspects.Quail has higher laying rate and the egg enriched nutrients,such as vitamins and minerals which considered as healthy nutritious food,while the cholesterol levels in quail egg in higher.In recent years,the quail industry has developed rapidly in China.It was urgent to reduce cholesterol content and improve quail egg quality through nutritional strategies regulation.Therefore,the objective of this study was conducted to investigate the effects of different levels of PSE supplemental on quail production performance,egg quality,blood biochemical indicators and nutrient utilization efficiency.A total of 110-d old,1 400 healthy quails were randomly divided into 5 group,each group with 7 replicates,with 40 quails in each replicate.A corn-soybean meal basal diet supplemented with PES at 0,150,300,450 and 600 mg/kg,respectively.Seven days were allowed for adjustment to the conditions,and then measurements were taken over 42 days.The results are as following:（1）compared with the basic diet,the laying rate increased 2.68%,4.31%,3.84%and5.12%when supplemented 150,300,450 and 600 mg/kg PSE,respectively（P<0.05）,the linear and quadratic regression equations for the PSE supplementary levels and laying rate are:Y=0.0064X+86.703（R²=0.821）and Y=-0.00001X²+0.0142X+86.118（R²=0.927）,respectively;no influence was observed feed to egg ratio,average daily feed intake and egg weight among 5 treatments（P>0.10）.（2）supplement with 150 mg/kg of PSE increased（P<0.05）the yolk weight of quail eggs by 10.6%and 8.86%than 0 mg/kg group on the d 21^stand d 42^nd,respectively;The quadratic regression equations for the PSE supplementary levels and yolk weight on d 21^stand 42^ndare:Y=-0.000002X²+0.0011X+3.5531（R²=0.406）and Y=-0.000002X²+0.0009X+3.5654（R²=0.424）,respectively;the proportion of egg yolk increased by 8.11%and 6.4%（P<0.05）.Egg shape index,eggshell strength,egg weight,egg white height,eggshell color,Haugh unit,eggshell thickness and egg yolk index for the quail eggs in 21^stday（P>0.10）and42^ndday were not influenced by PSE（P>0.10）.（3）Compared with the control group,supplementary with 150 mg/kg,300 mg/kg,450mg/kg and 600 mg/kg PSE,digestibility of dry matter increased 24.02%,36.59%,41.65%and 49.72%（P<0.05）,respectively;digestibility of organic matter was greater 26.95%,40.43%,45.90%and 54.69%（P<0.05）,and the total energy utilization efficiency increased13.25%,19.73%,22.83%and 28.28%（P<0.05）,respectively.The apparent digestibility of crude protein with 300 mg/kg,450 mg/kg,and 600 mg/kg PSE increased 33.46%,37.57%,and 52.62%（P<0.05）,respectively;apparent digestibility of ether extract increased 7.76%,9.76%,and 12.89%（P<0.05）,respectively;Calcium apparent digestibility increased 21.88%,31.93%and 50.31%（P<0.05）,respectively;apparent digestibility of phosphorus increased when supplemental 600 mg/kg PSE group than 0 mg/kg PSE group（P<0.05）.（4）Supplement with 300 mg/kg and 600 mg/kg PSE reduced the total cholesterol of quail eggs by 23.4%and 235.8%,respectively（P<0.05）;the linear and quadratic equations between PSE and total cholesterol shows following:Y=-0.0005X+0.5258（R²=0.801）and Y=-0.000001X²+0.0003X+0.4676（R²=0.959）.（5）Compared with the control group,supplementary with 300 mg/kg and 600 mg/kg PSE increase serum TG（P<0.05）.Serum TC content decreased with the increase of PSE addition level（P<0.05）.Adding 300 mg/kg and 600 mg/kg PSE reduce the content of HDL-C by 12.0%and 22%,respectively.（6）Compared with the control group,serum T-SOD improved 108.57%,106.7%,135.24%and 89.52%（P<0.05）when supplementary with 150 mg/kg,300 mg/kg,450 mg/kg and 600 mg/kg PSE,respectively;CAT increased 23.13%,28.36%and 65.67%in 150mg/kg,450 mg/kg and 600 mg/kg group（P<0.05）;GSH-Px was improved 9.3%when supplementary 600 mg/kg PSE than control group（P<0.05）.No difference was observed on MDA and T-AOC among treatments（P>0.10）.（7）Compared with the control group,no significant influenced was observed on the contents of liver LDL-C,TG,CAT,T-SOD,MDA and T-AOC（P>0.10）;the liver TC content reduced 20.99%supplementary with 150 mg/kg PSE（P<0.05）;supplementary with 300 mg/kg,450 mg/kg and 600 mg/kg PSE increased the liver GSH-PX enzyme activity by45.44%,27.83%and 27.83%,respectively（P<0.05）.In summary,PSE supplemental could increase the apparent digestibilities,laying rate,yolk weight and antioxidant properties of quail,while reducing the cholesterol content in quail eggs.Considering egg yolk weight,cholesterol and egg production rate,we suggested supplementary with 150～300 mg/kg PSE in the diets of egg quail.