中国乳业Issue(8)：81-87,7.DOI:10.12377/1671-4393.25.08.13
乳肉兼用牛发情期牛乳中孕酮与乳汁成分的变化
Changes in Progesterone and Milk Composition Traits in Dual-purpose Cattle During Estrus
摘要
Abstract
[Objective]To investigate the changes in progesterone and milk composition traits in dual-purpose cattle during estrus,reveal their regulatory mechanisms,and provide a scientific basis for optimizing breeding management.[Method]Sixty-five healthy dual-purpose cattle were selected.Progesterone concentrations during the estrous cycle were measured using enzyme-linked immunosorbent assay(ELISA),while milk fat rate,milk protein rate,and lactose content were determined with a fully automatic milk composition analyzer.The associations between progesterone and milk components were analyzed via linear mixed models(LMMs),multiple regression,and analysis of covariance(ANCOVA),with parity and lactation stage evaluated as regulatory factors.[Result]Progesterone exhibited significant dynamic changes during estrus,peaking at 48 hours pre-estrus and sharply declining on the day of estrus.Milk fat and protein rates fluctuated synchronously,showing strong positive correlations with progesterone(r>0.30,p<0.05).Lactose content varied minimally,with no significant association to progesterone(r<0.1,p>0.05).The progesterone-milk fat correlation was 23.60%higher in second-parity cows than in multiparous cows,with the strongest correlation observed during mid-lactation(r=0.42,p<0.01).[Conclusion]Progesterone significantly influences milk fat and protein synthesis by regulating mammary gland metabolic activity,with effects modulated by parity and lactation stage.These findings provided a critical time window and scientific basis for targeted nutritional interventions and reproductive management.关键词
乳肉兼用牛/孕酮动态变化/乳汁成分/发情期Key words
dual-purpose cattle/progesterone dynamics/milk composition/estrus period引用本文复制引用
张德敏,李强,宋磊,周青,胡洪杰,张淑二,刘育含..乳肉兼用牛发情期牛乳中孕酮与乳汁成分的变化[J].中国乳业,2025,(8):81-87,7.基金项目
山东省乡村振兴科技提振行动计划(2024TZXD024) （2024TZXD024）
山东省农业良种工程(2024LZGC019) （2024LZGC019）
