The Progeny test of Friesian sires for milk traits by using the contemporary comparison method

Abstract

In this study, the contemporary comparison method (CC) of half-sibs relation was used to estimate the breeding values of Holstein-Friesian sires for 305 -day milk yield (305-DMY) and basic components of milk traits, 409 records of cows that are daughters of ten sires in eight Syrian dairy farms where used. Result of the study showed differences in the estimated breeding values(ccEBVs), where the E Sire achieved the highest value of 305-DMY trait (254.47 kg), while the B Sire achieved the highest value of milk protein percentage (MPP), milk fat percentage (MFP)and milk lactose percentage (MLP) traits (0.822 %, 0.857 %and 1.09% respectively). According to their sires, daughters of E Sire outperformed the counterparts in the 305-DMY (p = 0.001), MPP (p = 0.001) and MFP (p = 0.04) traits (5701.44 kg, 3.55%, and 3.88% respectively). According to source of farm, daughters in Farm 5 achieved the highest value of 305-DMY trait (p=0.04) and daughters in the seventh farm achieved the highest value of MPP trait (p=0.007), the values were 5403.48 kg and 3.54 % respectively. Values of heritability (h2) for the traits of 305-DMY, MPP, MFP and MLP were 0.33,0.54,0.43 and 0.47 respectively. Most of genetic and phenotypic correlations coefficients were approaching to zero except the genetic relation between MLP and MPP and phenotypic relation between MFP and MPP (0.88 and 0.84 respectively).