Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian la...Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian laying hens were investigated and the possibility of quercetin to decrease cholesterol in eggs and Low Density Lipoprotein cholesterol（LDL-cholesterol） in laying hens were explored. A total of 240 laying hens at 29-week-old were randomly assigned to four treatments, with six replicates of 10 birds per replicate. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g · kg-1 quercetin for 8 weeks. Layer performance, lipid concentration in livers, yolks and serum were measured at the end of the experiment. The results showed that laying rate had a quadratic correlation with the level of quercetin（p=0.056） and was maximized by the supplement level of 0.2 g · kg-1 diet. When the level of dietary quercetin increased, feed-egg ratio decreased. Crude fat and the total cholesterol of livers decreased by supplementation of quercetin. The total cholesterols of yolks also decreased and had a quadratic correlation with the levels of quercetin（p=0.019）. Insulin increased by supplement of quercetin. In conclusion, quercetin improved the performance and reduced egg yolk cholesterol by affecting serum hormone levels.展开更多
This trial was conducted to evaluate the effect of quercetin on egg quality and components in laying hens of different weeks. A total of 240 healthy Hessian laying hens at 29, 39-week-old with similar body weight and ...This trial was conducted to evaluate the effect of quercetin on egg quality and components in laying hens of different weeks. A total of 240 healthy Hessian laying hens at 29, 39-week-old with similar body weight and laying rate were randomly divided into four groups with six replicates of 10 each replicate, respectively. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g-kg-1 quercetin for 8 weeks. The results showed that compared with the control, broken or soft shell rate significantly decreased at 0.2 and 0.4 g.kg-1 quercetin and eggshell thickness significantly increased at 0.4 g.kg-1 quercetin （P〈0.01） in laying hens at 39-47 weeks old; yolk protein significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 29-37 weeks old; while yolk protein significantly increased at three quercetin treatments in laying hens at 39-47 weeks old; yolk cholesterol significantly decreased by quercetin in laying hens at 29-37 weeks old （P〈0.05）; yolk total phospholipids significantly increased at 0.4 and 0.6 g kg-1 quercetin （P〈0.01） and yolk cholesterol significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 39-47 weeks old. In a word, quercetin affected egg quality and components to some extents in laying hens of different weeks, the older the hens became, the better improvement they would be. The optimum level of quercetin was 0.4 g kg-1 in the basal diet.展开更多
The technology of automatic carbon tape laying for structural composite parts is introduced. The most effective form of automatic carbon tape laying technology is presented with emphasis.
The United States and theSoviet Union announced agreementin principle on September 18 ona historic treaty wiping out allintermediate-range nuclear wea-pon which would be signed at asuperpower summit this year. The 42n...The United States and theSoviet Union announced agreementin principle on September 18 ona historic treaty wiping out allintermediate-range nuclear wea-pon which would be signed at asuperpower summit this year. The 42nd session of the UNGeneral Assembly began a 3-weekgeneral debate on September 21. The US naval forces in theGulf attacked and seized anIranian ship on September 21 toprevent it from laying mines.The ship was destroyed by the展开更多
学过一点英语的人都知道英语catch hold of、take hold of、seize hold of、get hold of和lay hold of都表示“抓住”，而且有些人在表达“抓住”时会毫无区别地使用它们。事实上，它们的中文意思虽然都可译作“抓住”，但这五个“抓住...学过一点英语的人都知道英语catch hold of、take hold of、seize hold of、get hold of和lay hold of都表示“抓住”，而且有些人在表达“抓住”时会毫无区别地使用它们。事实上，它们的中文意思虽然都可译作“抓住”，但这五个“抓住”是有细微差别的，可谓各司其职。展开更多
基金Supported by Heilongjiang Provincial Government(C2016017)Harbin Science and Technology Bureau(2015RQXXJ014)
文摘Quercetin has a variety of biological activities. However, its application as a feed additive in poultry production is limited. In this study, the effects of quercetin on performance and lipid metabolism in Hessian laying hens were investigated and the possibility of quercetin to decrease cholesterol in eggs and Low Density Lipoprotein cholesterol（LDL-cholesterol） in laying hens were explored. A total of 240 laying hens at 29-week-old were randomly assigned to four treatments, with six replicates of 10 birds per replicate. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g · kg-1 quercetin for 8 weeks. Layer performance, lipid concentration in livers, yolks and serum were measured at the end of the experiment. The results showed that laying rate had a quadratic correlation with the level of quercetin（p=0.056） and was maximized by the supplement level of 0.2 g · kg-1 diet. When the level of dietary quercetin increased, feed-egg ratio decreased. Crude fat and the total cholesterol of livers decreased by supplementation of quercetin. The total cholesterols of yolks also decreased and had a quadratic correlation with the levels of quercetin（p=0.019）. Insulin increased by supplement of quercetin. In conclusion, quercetin improved the performance and reduced egg yolk cholesterol by affecting serum hormone levels.
基金Supported by Heilongjiang Department of Education(12541010)Heilongjiang Department of Human Resources and Social Security(2014-2015)+1 种基金Harbin Science and Technology Bureau(2015RQXXJ014)Academic Team Construction of Northeast Agricultural University(2014-2017)
文摘This trial was conducted to evaluate the effect of quercetin on egg quality and components in laying hens of different weeks. A total of 240 healthy Hessian laying hens at 29, 39-week-old with similar body weight and laying rate were randomly divided into four groups with six replicates of 10 each replicate, respectively. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g-kg-1 quercetin for 8 weeks. The results showed that compared with the control, broken or soft shell rate significantly decreased at 0.2 and 0.4 g.kg-1 quercetin and eggshell thickness significantly increased at 0.4 g.kg-1 quercetin （P〈0.01） in laying hens at 39-47 weeks old; yolk protein significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 29-37 weeks old; while yolk protein significantly increased at three quercetin treatments in laying hens at 39-47 weeks old; yolk cholesterol significantly decreased by quercetin in laying hens at 29-37 weeks old （P〈0.05）; yolk total phospholipids significantly increased at 0.4 and 0.6 g kg-1 quercetin （P〈0.01） and yolk cholesterol significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 39-47 weeks old. In a word, quercetin affected egg quality and components to some extents in laying hens of different weeks, the older the hens became, the better improvement they would be. The optimum level of quercetin was 0.4 g kg-1 in the basal diet.
文摘The technology of automatic carbon tape laying for structural composite parts is introduced. The most effective form of automatic carbon tape laying technology is presented with emphasis.
文摘The United States and theSoviet Union announced agreementin principle on September 18 ona historic treaty wiping out allintermediate-range nuclear wea-pon which would be signed at asuperpower summit this year. The 42nd session of the UNGeneral Assembly began a 3-weekgeneral debate on September 21. The US naval forces in theGulf attacked and seized anIranian ship on September 21 toprevent it from laying mines.The ship was destroyed by the
文摘学过一点英语的人都知道英语catch hold of、take hold of、seize hold of、get hold of和lay hold of都表示“抓住”，而且有些人在表达“抓住”时会毫无区别地使用它们。事实上，它们的中文意思虽然都可译作“抓住”，但这五个“抓住”是有细微差别的，可谓各司其职。
