Cytoplasmic inheritance and maternal effect in degree of some genetic resistance of the reproductive disease in Holstein cattle


At the Nasr Dairy Cattle Station , United Company for Animal Resources (50 Km South of Baghdad ), over period from 2005 to 2007, 750 Holstein cow were randomly picked out from the herd .The aim of this study was to investigate the role of cytoplasmic inheritance ,maternal effect of the genetic resistance of reproductive disease of mastitis (M1) , metritis (M2) and retained placenta (R), and to estimate of heritability by various methods. The SAS program was used for statistical analysis. Components of variance for the random effects in the employed mixed model was estimated by using the Restricted Maximum Likelihood procedure(REML). The heritability of the M1 , M2 and R were 0.29, 0.35 and 0.26 respectively by using heritability estimate by half-sib whereas decreased to o.23, 0.24 and 0.19 respectively at the estimate by half-sib with adjusted of maternal effects, while these estimates were 0.34 , 0.36, 0.36 respectively at the estimate by regression (daughter dam). The variance of maternal effect in M1, M2 and R were 412.66, 6565.17, and 319.33 respectively , but the variance of cytoplasmic were 22.54, 9.886 and 2.82 respectively.