Influence of Certain Environmental Factors on Birth Weight in Angus, Charolais, Hereford and Their Crossbred Cattle

Angus, Hereford, Charolais종(種)과 그 교잡종(交雜種)의 생시체중(生時體重)에 미치는 환경요인(環境要因)의 영향(影響)

This study was conducted from 1974 to 1977 at Chedong Animal Farm in Che-Ju to determine the effect of sex of calves, birth year and season, breeds and crossing methods on the birth weight of cattle. A total of 1020 calves from Angus, Charolais, Hereford breeds and their crossbred were used for the study and least square methods was applied to analysis the data. Birth weight of male calves was 1kg heavier than that of female. Highly significant differences were obtained in the effects of birthyear on the birth weight, i.e. the cattle born in 1976 and 1977 was 0.9 and 0.2kg heavier in birth weight than those born in 1975. The cattle born in 1974, when the farm was established, was 1.7kg lighter than those in 1975. The calves born in the spring and the summer was 0.6 and 0.3kg heavier in birth weight than those born in the winter. The calves born in the fall was 0.9kg lighter than the calves born in the winter. In birth weight, Charolais breed were 0.4kg heavier than those from Hereford breed. Angus breed were 1.1kg lighter than Hereford. The crossbred between Charolais and Hereford breed were 1.5kg heavier than the Hereford. The birth weight of calves from Angus and Hereford crossbred and Angus and Charolais crossbred were 0.6 and 0.4kg lighter, than Hereford breed respectively.

본(本) 연구(硏究)는 1974년(年)부터 1977년(年)까지 4개년간(個年間)에 걸쳐 제주도(濟州道) 소재(所在) 제동목장(濟東牧場)에서 사육(飼育)된 Angus, Charolais, Hereford종(種)과 그들 교잡종(交雜種) 총(總) 1020두(頭)에 대한 자료(資料)를 최소자승법(最小自乘法)을 통(通)해 통계분석(統計分析)하여 자우(仔牛)의 성(性), 출생년도(出生年度), 출생계절(出生季節), 품종(品種) 및 교배방법(交配方法)등이 자우(仔牛)의 생시체중(生時體重)에 미치는 영향을 추정(推定)하였다. 1. 생시체중(生時體重)에 대한 성(性)의 효과(效果)는 숫송아지가 암송아지 보다 1kg 더 무거웠다. 2. 출생년도(出生年度)의 효과는 1%수준(水準)에서 유의성(有意性)이 인정(認定)되었으며 '76, '77년도(年度)의 생시체중(生時體重)이 '75년도(年度)보다 0.9kg 0.2kg 더 무거웠고 목장개설(牧場開設) 초년도(初年度)인 '74년도(年度)는 '75년도(年度)보다 1.7kg 가벼웠다. 3. 출생계절(出生季節)의 효과(效果)는 봄과 여름에 출생(出生)된 송아지가 겨울에 출생(出生)된 송아지보다 0.6, 0.3kg무거웠으며 가을에 출생(出生)된 송아지는 0.9kg 가벼웠다. 4. 품종(品種)과 교배방법(交配方法)의 효과는 Charolais 종(種)이 Hereford종(種)보다 0.4kg무거웠으며 Angus종(種)은 1.1kg가벼웠다 Charolais종(種)과 Hereford종(種)의 교잡종(交雜種)은 Hereford종(種)보다 1.5kg 무거웠고 Angus와 Hereford 교잡종(交雜種), Angus와 Charolais교잡종(交雜種)은 Hereford종(種)보다 각각(各各) 0.6, 0.4kg 가벼웠다.