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Abstract A total of 2396 records of 673 of one commercial Holstein Friesian herd raised in Domiatta government were collected from 1999 to 2004 in the first five parities. Genetic, phenotypic correlations and breeding values for productive, reproductive and somatic cell count (SCC) traits were analyzed by using single-trait and multi-trait animal model analyses of each productive and reproductive, examined traits jointly with SCC. Traits studied were total milk yield (TMY) (kg), milk yield in months Ml, M2,M8, days in milking(DIM)(day), SCC in months SCC1, SCC2,SCC8 (cell/ml), age at first calving (AFC)(month), number of inseminations per conception(NSC)(inseminations) and days open (DO)(day). Means of TMY, DIM, Ml, SCC1, AFC, NSC and DO were 6715.5 kg, 319.8 days, 16.3 kg 505.2 xlO3 cell/ml, 28.3 months, 1.97 services and 144.5 days, respectively. Also, means of M2, SCC2, M3 and SCC3 were 18.6 kg, 464.1 xlO3 cell/ml, 19.03 kg and 376.2x103 cell/ml, respectively. Estimates of heritability of TMY, DIM, Ml,SCC1, AFC, NSC and DO were 0.34, 0.22, 0.10, 0.04, 0.20, 0.02 and 0.02 by single-trait, and were 0.40, 0.20, 0.24, 0.10, 0.27, 0.05 and 0.26, respectively by multi-trait. Estimates of heritability of M2, SCC2, M3 and SCC3 were 0.06,0.06, 0.04 and 0.05by single-trait, and were 0.20, 0.10, 0.21and 0.11, respectively by multi-trait. Genetic correlation between SCC and milk productive traits were positive and ranged from 0.09 to 0.33. Estimates of genetic correlation between SCC and reproductive traits were also positive and ranged from 0.11to 0.35. Standard deviations and rang of breeding value for multi-trait analysis were higher than single-trait analyses for all studied traits. Correlations between EBV of all animals were positive ( from 0.26 to 0.9) between all studied traits except between DO and each of TMY, Ml and M3 were negative (-0.205 to -0.016). |