Knight C H, Peaker M
Q J Exp Physiol. 1984 Apr;69(2):331-8. doi: 10.1113/expphysiol.1984.sp002809.
Mammary development was assessed in lactating goats using a combination of biopsy (for analysis of nucleic acids) and udder volumes (for determination of gross size). Single biopsies were shown to be highly representative of the composition of the whole gland provided that they were taken from carefully selected sites. Results indicated an increase in both milk yield and the size of the mammary cell population ( DNAt ) over the first three weeks of lactation. Yield, but not DNAt , continued to increase until peak lactation at around week eight. As milk yield fell between weeks eight and twenty-three the size of the cell population also decreased; beyond week twenty-three and until week thirty-six DNAt stabilized but yield continued to fall. It is concluded that the first part of the increase in milk yield during ascending (early) lactation in goats can be attributed to proliferation of secretory cells, but subsequently there is an increase in the amount produced by each cell. Likewise, declining lactation is initially characterized by a loss of cells, and yield per cell falls later.
利用活检（用于核酸分析）和乳房体积测量（用于确定总体大小）相结合的方法，对泌乳山羊的乳腺发育情况进行了评估。结果表明，只要从精心挑选的部位取材，单次活检就能高度代表整个腺体的组成情况。结果显示，在泌乳的前三周，产奶量和乳腺细胞群体大小（DNA总量）均有所增加。产奶量持续增加，直至第八周左右达到泌乳高峰，但此时DNA总量不再增加。在第八周和第二十三周之间，随着产奶量下降，细胞群体大小也随之减小；在第二十三周之后直至第三十六周，DNA总量趋于稳定，但产奶量继续下降。由此得出结论，山羊泌乳初期（上升期）产奶量增加的第一阶段可归因于分泌细胞的增殖，但随后每个细胞的产量增加。同样，泌乳量下降最初表现为细胞数量减少，随后每个细胞的产量下降。
