The Evolution of mammary glands at different stages in Sarda dairy ewes: preliminary results

The significance of cytological evolution of alveolar cells explains differences in milk yield that resulted in a different shape of lactation curve. In this paper, investigation of cellular background for this pattern was studied morphometrically in mammary gland of dairy ewes prior to lambing to involution. The ratio of epithelial to the luminal area was greatest at 7 days from lambing, it diminished on day 30 and 60 of lactation and it increased thereafter on day 150 of lactation and on day 7 of involution. The evolution of mammary tissues shows a clear decrease in stromal mass from prepartum until 60 DIM. Structural changes of mammary tissues during late pregnancy, lactation and dry off, can be used as a basis to estimate the evolution of the number of secretory cells in dairy ewes.