Study On Breed Characteristics And Laying Performance Of Blue-shelled Layers

Chinese progenitor breeding layers are variety,as a country on the map poultry,eggs chain of production as important as chain of consumption.In order to meet the trend of China's egg industry development,enhance the economic development level of agriculture and rural areas,Local lines breeding has become the key to wealth.Dongxiang blue-shelled layers is the hybrid variant of the local strains,which has the nearest genetic distance with Taihe Silkies.These typical features are flexible,adaptability,strong resistance to crude feed.Ferocious cock has big eyes sparkle and optimum meat quality traits.Through systemic breeding,the local strains have higher number of gene heterozygosity that affects the egg production.Phenotypes changed obviously,and laying performance has a difference.Therefore,it is necessary to select high production and quality breeding individuals.This experimental study is object to establish individual files through traditional breeding methods,and learn about the laying performance of different phenotypes.This paper aims to ascertain growth and development rules and the phenotype factors affecting the performance of Dongxiang blue-shelled laying hens.Based on the first step,learn the structure and properties of Dongxiang blue-shelled eggs,so as to provide theoretical basis for breeding high production and quality of laying hens.The test results were as follows:1.We select 96 Dongxiang blue-shelled laying hens and 48 Dongxiang blue-shelled roosters and respectively determine the growth rate at different ages.The result shows Dongxiang blue-shelled laying hens' growth rate is 137.88%between 0 week age to 2 weeks age,then growth rate is 69.19%between 2 weeks age to 10 weeks age,and growth rate is 7.91%between 10 weeks age to 17 weeks age.The Gompertz model can accurately reflect the growth regularity of layers,which can be expressed by equation W=1192.54e-3.84exp(-0.187t)(R2=0.999).The Dongxiang blue-shelled laying cocks' growth rate is 103.67%between 0 week age to 2 weeks age,then growth rate is 62.78%between 2 weeks age to 10 weeks age,and growth rate is 30.73%between 6 weeks age to 10 weeks age.The Gompertz model can accurately reflect the growth regularity of roosters,which can be expressed by equation W=2516.56e-428exp(-0.123t)(R2=1).The 17 weeks body weight has significant correlation with other four ages body weight,and starting with birth weight,the ages increase more the greater the correlation coefficient.2.We make 120 black-cockscomb laying hens as a group,feed separately with the red-cockscomb laying hens.In addition,we select 120 Dongxiang laying hens with red cockscomb feature to a high performance group together.All of them were feed in the same stage house.The feeding trial lasted for 8 days.The red-cockscomb production rate is 67.24%,the black-cockscomb production rate is 53.98%,the high production rate is 74.30%,the low production rate is 60.19%;during the period of statistics,the change trend of egg production rate in the red crown group and the high yield group was relatively stable.The local lines' laying performance improved after breeding.A further study suggest that higher performance groups layers' eggshell colors has three types as the blue?the olive green and the brown and the respectively proportion is 76.64%,13.45%,6.71%.The result shows eggshell color is not uniform.3.With chickens in the same stages house as research materials,we compared the quality of eggs,within strain different characteristics'(red and black crest,light and green eggshell,high and low laying performance)egg weight and egg-shell weight were tested highly significant correlation relationship,the correlation coefficient ranges from 0.894 to 0.991.The egg weight has no significantly correlation with egg white weight and egg yolk weight.30.14 percent of egg weight is egg yolk and 59.61 percent of egg weight is egg white.Egg weight and short diameter has lager correlation.Therefore,the short diameter decide egg weight more than long diameter.By contrast Dongxiang laying hens' blue-shelled eggs and brown eggs,the result shows that Dongxiang laying hens has the lower index quality with egg yolk color,albumen height,Haugh unit,egg weight,yolk weight.But,The egg shell strength significantly greater than the Hy-line strains,remains the local strain characteristics.Blue-shelled eggs has the smaller egg shape index,The shape index between 1.26 to 1.30 in each experimental group,appearance of partial round.4.In the ages of 26th,27th,28th weeks,the eggs number in upper cages larger than the middle cages and lower cages,there is no significant differences;Egg weight distribution can be expressed as the middle>upper>lower.Three periods of egg weight showing a steady growth trend.Curve fitting the egg weight of each cages show that change chart with increasing trend.Results show that three distributions are not the same.Upper cages have the maximum ratio of abnormal eggs during the statistical,then middle cages have the least ratio of abnormal eggs.5.The fertilization rate reached the maximum after 2?3 days of artificial insemination,then the fertilization rate gradually decreased.The concluded is that the high production layers has better fertilization rate than the low production layers,and it's correlation requires further study.