Estabilshment Of Misgurnus Anguillicaudatus Families And Genetic Analysis Of Their Growth Traits

1. Comparison of growth among 48 Misgurnus anguillicaudatus families at fingerling stageAccording to the nest design, forty eight full-sib families of Misgurnus anguillicaudatus were obtained by artificial fertilization. The growth of fingerlings was measured during 6 months, and was analyzed by analysis of variance and multiple comparisons. The result showed that the differences among growth performances of the progeny of different families were extremely significant. F3, F6, F22 and F46 families with the average full length of 9.03, 9.07, 9.23 and 9.15 cm respectively at 6 months grew faster than other families significantly. F1, F6, F22, F46 and F50 families with the average weight of 3.78, 3.74, 3.85, 3.87 and 3.59g respectively at 6 months grew faster than other families significantly. It was considered that F6, F22 and F46 families were of excellent pedigree, and could be used as the basis populations for further genetic selection.2.Estimates for the heritability of total length and body weight of Misgurnus anguillicaudatus at 4 monthsThe parents of sex mature Misgurnus anguillicaudatus were employed and the method of unbalanced nest design and artificial insemination techniques were used. Twenty-one half-sib families and forty-two total-sib families of Misgurnus anguillicaudatus were obtained by the design that each male mated with 2 females. According to quantitative genetics theory, causal components of phenotypic variance were calculated with the General Line model(GLM)procedure of the SPSS software, and the heritability of some growth traits of Misgurnus anguillicaudatus at 4 months were statistically studies. The estimates of narrow-sense heritabilities were 0.57-0.62 for total length and 0.39-0.58 for body weight. Narrow-sense heritabilities of paternal half-sib were 0.57 for total length, and 0.39 for body weight. The dam components were greater, suggesting large non-additive genetic effects or common environment effects that could not be differentiated. The estimated heritability indicated significant additive variation for total length and body weight at 4 months of Misgurnusanguillicaudatus.It was suggested that the effect for improvement through selection was particularly good for total length and body weight at larva stage of Misgurnus anguillicaudatus.3.Genetic Diversity of five Misgurnus anguillicaudatus Families as Revealed by MicrosatellitesAdoping microsatellite markers to analyze 10 pairs of primers, genetic diversity of five families (F1,F22,F24,F46,F50).The results showed the number of allele at each l ocus was 1~6, the average allele number was 4; effective allele number was 1.91~5.90; average effective allele number was 2.98; average observed heterozygosity value was 0.72; the average expected heterozygosity value was 0.65. All of these five families were middle polymorphism, and the ascending order the PIC was family22, family1, family50, family24 and family46, respectively. The coefficient of strain differentiaton among the families was 0.17, and there was certain genetic differentiation existed among the five families. The clustering result showed that the family 1 and 24 shared the nearest relationship, which was the furthest to family 46.