韓牛 牝牛의 Body Condition Score가 繁殖形質에 미치는 影響

Abstract

Data from five Hanwoo breeding farms were collected to analyze the effects of parity, season, nutrition and reproduction on body conditions of heifers and cows and to analyze the relationships of body conditions with reproductive performance and body growth. Analytic models included farms and parity which were run through SAS to estimate least squares means and correlation coefficients between traits - body condition scores(BCS) of 1(very emaciated) through 9(very obese) scale at service and at calving, calving interval, days to rebreeding, gestation length, number of services per conception. Overall averages were 4.55 for BCS at service, 5.42 for BCS at calving, 406.7days of calving interval, 287.7days of gestation length, 66.2days from calving to first service and 1.78 times of services per conception. Number of services per conception was 1.50~1.74 times for the cows of BCS 5 or under and 2.00~3.00 for those of BCS 6 or higher. Body weight of calves from cows observed averaged 23.3kg at birth and 70.7kg at weaning. 57 percent of cows showed BCS 4~5 at services while 46 percent of those showed 5~6 at calving. Estimated phenotypic correlation coefficients of BCS at service with BCS at calving, calving interval, gestation length, number of services per conception were low but positive: 0.16, 0.26, 0.08 and 0.06, respectively. Phenotypic correlations of BCS at calving with calving interval, gestation length and number of services per conception were estimated to be also low and positive: 0.10, 0.13 and 0.10, respectively. However, phenotypic correlations between calving interval and gestation length, and between gestation length and number of services per conception were negative but low as -0.11 and -0.13 each.