产前挤奶对奶牛泌乳发生定量形态学的影响。

Effect of prepartum milk removal on quantitative morphology of bovine lactogenesis.

作者信息

Akers R M, Heald C W, Bibb T L, McGilliard M L

出版信息

J Dairy Sci. 1977 Aug;60(8):1273-82. doi: 10.3168/jds.S0022-0302(77)84022-8.

Abstract

The effect of prepartum milking on bovine mammary histology and milk composition was studied in five Holstein cows. One udder half was milked twice daily starting 10 days before the estimated calving date. On udder half was not milked until 2 days postpartum when all quarters were milked and two tissue samples per quarter were taken for morphological analyses. Lactose, casein, and fat concentrations differed from prepartum-milked to postpartum-milked quarters (.82, -1.44, and 3.29%). Quarters milked prepartum were more developed: mature epithelium 24.8%, immature epithelium - 8.9%, total epithelium 15.6%, stroma -24.8%, and alveolar lumen 8.5%. Most alveolar cells in prepartum-milked halves had prominent rounded basal nuclei, hypertrophied secretory vesicles, and a mixed array of lipid droplets. Cells within alveoli were morphologically similar. Secretory epithelial cells from postpartum-milked glands had irregular randomly located nuclei, indistinct Golgi, variable lipid content, and less cytoplasm. These differences demonstrate the importance of prepartum-product removal on secretory cell development and subsequent milk production.

摘要

在五头荷斯坦奶牛身上研究了产前挤奶对牛乳腺组织学和乳汁成分的影响。从预计产犊日期前10天开始，对一侧乳房每天挤奶两次。另一侧乳房直到产后2天所有乳腺都开始挤奶时才进行挤奶，并从每个乳腺采集两份组织样本用于形态学分析。产前挤奶的乳腺和产后挤奶的乳腺在乳糖、酪蛋白和脂肪浓度上存在差异（分别为0.82%、-1.44%和3.29%）。产前挤奶的乳腺发育更完善：成熟上皮细胞占24.8%，未成熟上皮细胞占8.9%，总上皮细胞占15.6%，间质占-24.8%，肺泡腔占8.5%。产前挤奶一侧乳房的大多数肺泡细胞具有突出的圆形基底核、肥大的分泌小泡和混合排列的脂滴。肺泡内的细胞在形态上相似。产后挤奶乳腺的分泌上皮细胞具有不规则随机分布的细胞核、不清晰的高尔基体、可变的脂质含量和较少的细胞质。这些差异表明产前去除产物对分泌细胞发育和随后的产奶量具有重要意义。