Study on the Reproductive Performance of Dairy Cattle at Alpine Area in Kanweon-Do

강원도 고지 사육 유우의 번식실태에 관한 조사

The present study was conducted to examine the reproductive performance of dairy cow at alpine area. 1,515 dairy cows were managemented at above 800m of sea level around the Dea-Gwan Ryeong in Kangweon-Do. The results at this study were as follows ; 1. The average first estrus was 105.0 days after pastruation. 2. The highest percentage ofpregnancy(26.4%) and parturation(27.6%) were obtained at September to November and June to August, respectively. 3. The rate of pregnancy was 61.0%. Pregnancy rates according to insemination times of 1, 2 and 3 were 60.8, 23.5 and 9.8%, respectively and insemination time per pregnancy was 1.64. 4. Ages of first inseminatin, pregnancy and parturition of heifer were 17.9, 18.6 and 27.7 months, respectively. 5. Time of postpartum pregnancy was 133.0 days after parturition, and pregnancy period and calving interval were 279.6 and 410.3 days, respectively. 6. Six ratio of offspring was 52.1% of female versus 47.9% of male, and the proportion of twins was 0.65%. 7. The proportions of normal parturition, stillbirth and abortion were 91.9, 2.2 and 5.9%, respectively.