Abstract: Objective: To explore the changing pattern of lactose content during mammary gland development of Holstein cows. Methods: High-performance liquid chromatography was used to determine lactose content. Results: Lactose was detectable in the mammary gland during the perinatal period, and showed an increasing trend during the lactation period, reaching a peak after 140 d of lactation, and then a dramatic decrease during the involution period, reaching a very low level after 30 d of involution. In conclusion, lactose content exhibits different levels in the mammary gland of Holstein cows during different physiological periods.

Key words: Hostein cow；mammary gland development；lactose content

摘要： 目的:研究荷斯坦奶牛乳腺发育中乳糖的变化规律.方法:高效液相色谱法测定荷斯坦奶牛乳腺发育中乳糖的含量.结果:围产期,乳腺中才出现可检测到的乳糖；泌乳期乳糖含量增高,泌乳140d达到峰值;退化期乳腺乳糖含量迅速降低,退化30d含量很少.结论:不同生理时期,荷斯坦奶牛乳腺中的乳糖含量不同.

关键词: 荷斯坦奶牛；乳腺发育；乳糖含量