국내 Holstein종 젖소의 경제형질과 착유량에 따른 소득의 유전모수 추정

Abstract

Korean Animal Improvement AssociationABSTRACTThe data including milk yields, fat and protein percent for 628,395 heads collected by National Agricultural Cooperative Federation, 15 type traits and final score for 62,262 heads collected by Korea Animal Improvement Association, which were born in 1998 to 2004, and net profits calculated from milk price and raising expenses of individuals were used to estimate genetic parameters. The highest positive genetic correlation, 0.81, was shown between body depth(BD) and loin strength(SR). Genetic correlations between body depth(BD) and udder depth(UD), front teat placement(TP) and front teat length(TL) were '0.23, which were lowest among the linear type traits. Furthermore, medium level of negative genetic correlations were shown the milk yield with milk contents rate traits. Mostly low level of positive genetic correlations were shown between the milk traits and linear score traits except milk yield and stature. Most of the genetic correlations of between the linear score traits and net profit were low level of positive or negative genetic correlations. Among the genetic correlations, body depth(BD), angularity(DF) and rear attachment width(UW), and final score(FS) with net profit were high as 0.17, 0.17, 0.18 and 0.18, respectively. Finally all of the genetic correlations between net profit and milk traits were positive and higher than the linear traits with positive genetic correlations. The results of this study suggest that net profit has been related with the linear traits, such as body depth(BD), angularity(DF) and rear attachment width(UW) traits, and furthermore, milk traits including yield and contents rates influence positively and greatly on net profit. (Key words :Milk yield traits, Linear type traits, Net profit, Genetic parameter, Genetic parameter)