The Analysis Of Some Egg Traits With The Software Major-gene Plus Polygene Mixed Genetic Model

In this study, Suqin green-eggshell layer black feather pure lines and single cristaWhite Leghorn acted as parents to constructed resource population, we measured the eggquality in the period of first egg laying,32,36,40,44,48,52and56-week-old of thegeneration F2in the resource population, the purpose of this study was to analysis thechange regular pattern of egg quality in the whole laying period;On the other hand, weused the software major-gene plus polygene mixed genetic model SEA-G4F2whichcame from Nanjing Agricultural university to analysis some egg traits, in order to exploretheir genetic regular pattern, and provide the bases of QTL mapping,genome-wideassociation analysis and molecular marker-assisted selection, and provide some academicguidance for the breeding of Suqin green-eggshell layer.the main results were as follows:1) The results of egg quality variation were: eggshell color L generally showed agrowth trend in the whole laying period, but a and b of eggshell color were showed adownward trend; egg weight、yolk weight and eggshell weight had a obvious variation inthe whole laying period, all of them had a growth trend; the change of eggshell strengthand Haugh unit in the whole laying period were generally became more and more smallwith the increase of age; the variation of egg shape index and eggshell thickness in thewhole laying cycle were tiny; yolk color and albumen height had a complex variation,the change of yolk color from first egg laying to32-week-old was diminution,32to36-week-old was became more and more large,36to40-week-old had a downward trend,after the40-week-old generally had a growth trend; the variation of albumen height fromfirst egg laying to40-week-old was became higher with the increase of age,40to48-week-old had a downward trend,48to52-week-old became more and more higher,the change regular pattern after52-week-old was a downward yrend.2): The model of40-week-old egg numbers was model E, namely two pairs ofadditive-dominance-epistatic major-gene plus additive-dominance-epistatic polygenemixed genetic model, the heritability of major-gene was0.215.3): The results of the first egg laying traits which were analysed by major-gene pluspolygene mixed genetic model were: the model of the age at first egg laying was E,namely two pairs of additive-dominance-epistatic major-gene plusadditive-dominance-epistatic polygene mixed genetic model, the heritability ofmajor-gene was0.2506; the best model of the weight at first egg laying was model E-1,which named two pairs of additive-dominance-epistatic major-gene plusadditive-dominance polygene mixed genetic model, the heritability of major-gene was0.6328, and this indicated that the weight at first egg laying was mainly controlled bymajor-gene.4): The results of the40-week-old egg quality traits which were analysed bymajor-gene plus polygene mixed genetic model were: the models of all the eggweight,eggshell color a,eggshell weight,eggshell strength,Haugh unit and egg indices were model E, namely two pairs of additive-dominance-epistatic major-gene plusadditive-dominance-epistatic polygene mixed genetic model, their heritability ofmajor-gene were respectively0.4307,0.9262,0.1233,0.1321,0.1471and0.1413, theheritability of polygene of egg weight and eggshell color a were0.0254and0.0055, thepolygene heritability of the other traits were0; the optimal model of eggshell colorL,b,albumen height,yolk color and yolk weight were model E-1,which was two pairs ofadditive-dominance-epistatic major-gene plus additive-dominance polygene mixedgenetic model, their heritability of major-gene were respectively0.4991,0.7377,0.1932,0.358and0.2105, the polygene heritability of the other traits werealso0.