| 摘要: |
| 用不完全γ函数拟合了西安市奶牛群189个泌乳期的泌乳曲线,并应用最小二乘法分析了产犊月份、年份、胎次、干奶期、产奶量及畜群对泌乳曲线参数与性状的影响。研究结果表明,产犊月份、胎次及干奶期对泌乳曲线形状均有显著影响;产奶量仅影响泌乳曲线的相对位置;产犊年份与畜群对泌乳曲线无任何明显影响。研究发现,以干奶期为60～90d、在冬季或春季产第四胎的乳牛泌乳量最高。 |
| 关键词: 乳牛,泌乳曲线,不完全γ函数 |
| DOI： |
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| AN ANALYSIS OF FACTORS AFFECTING THE LACTATION CURVE IN DAIRY CATTLE |
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Wang Jinliang
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| Abstract: |
| The incomplete gamma function is used to generate lactation curves for 189 lactations of Holstein cows from Xian Dairy Herds. The effects of freshing months, freshing years, conception numbers, dry periods, milk production and herd on the lactation curve parameters and traits are analyzed by the least square. Results show that freshing months, conception numbers and dry periods affect the shape of lactation curves significantly, and that milk production only affects the relative position of lactation curvesj and that freshing years and herds have no significant effect on the lactation curves. It is found that the highest milk production is the 4 th conception of cows in winter or spring seasons with a dry period of 60-90 days. |
| Key words: Dairy cattle,lactation curve,incomplete gamma function |
