Correlations of Genic Heterozygosity and Variances with Heterosis in a Pig Population Revealed by Microsatellite DNA Marker |
J. H. Zhang, Y. Z. Xiong, C. Y. Deng |
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Abstract |
Correlation of microsatellite heterozygosity with performance or heterosis was reported in wild animal populations and domestic animal populations, but the correlation with heterosis in a crossbreeding F1 pig population remained uncertain. To explore this, we had random selected and mated Yorkshire횞Meishan (F, n = 82) and their reciprocal (G, n = 47) to F1, and used the two straightbreds as control groups (Yorkshire = 34, Meishan = 55), and observed the heterosis of birth weight (BWT), average daily gain (ADG) and feed and meat ratio (FMR). Two Kinds of measurement-individual heterozygosity (IH) and individual mean d 2 (lg value, ID) were used as index of heterozygosity and variance from 39 microsatellite marker loci to perform univariate regression analysis against heterosis. We detected significant correlation of IH with BWT in all of F1 (F+G) and in F. We observed significant correlation of ID with ADG in all of F1(F+G), and with FMR in all of F1(F+G) and in F. There was significant maternal effect on heterosis, which was indicated by significant difference of means and distribution of heterosis between F and G. This difference was consistent with distributions of IH and ID, and with difference of means in F and G. From this study, it would be suggested that the two kinds of genetic index could be used to explore the genetic basis of heterosis in crossbreeding populations but could not determine which is better. |
Keywords:
Pig; Heterosis; Microsatellite; Individual Heterozygosity; Individual Mean d2 |
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