[IX-29-13_14] 遺伝・育種 (IX-午前)

[IX29-13E] Genetic study for pregnancy rate in Japanese Black cows

^○Setiaji Asep^1,2,3, Oikawa Takuro^1,2 (1.Kagoshima Univ., 2.Univ. of the Ryukyus, 3.Diponegoro Univ. Indonesia)

The aim of the study was to estimate genetic parameters of pregnancy rate at three parities of cows, to estimate repeatability and genetic correlations with other female reproductive traits. The reproductive traits included: pregnancy rate (PR), gestation length (GL), interval from calving to first insemination (CF), days open (DO) and calving interval (CI). Data across multiple parities were analyzed using a multi-trait model and using a repeatability model. Averages of the reproductive traits are 0.68%, 289.30d, 73.25d, 102.55d and 392.07d for PR, GL, CF, DO and CI, respectively. Estimated heritabilities using multi-trait model were ranging from 0.021 (PR at fourth parity) to 0.072(CF at fourth parity). Genetic correlations between traits among parities were high (from 0.882 to 0.988). Estimated heritabilities using repeatability model were ranging from 0.022 for PR to 0.059 for CF. Low repeatability estimated for all traits. PR showed close genetic correlations with DO and CI, and moderate genetic correlations with CF and GL.