Progesterone and Corticosteroids in the Initiation of Lactation in the Sow

Publisher Website
Google Scholar
Abstract
The concentration of lactose in the mammary secretion from individual glands of 2 sows increased significantly (P < 0.01) between 0 and 24 h after parturition. In 6 sows studied during the perinatal period there was a negative correlation (r = -0.80; P < 0.02) at parturition between the concentration of progesterone in the blood and the concentration of lactose in the mammary secretion. The increase in concentration of lactose in the mammary secretion after parturition was related to the timing of the decline of plasma progesterone to low levels. The initiation of lactation occurs within 24 h of parturition in most sows. The hypothesis that progesterone withdrawal acts as the trigger was examined. Neither the changes in corticosteroid binding globulin nor the changes in total corticosteroids were temporally related to the initiation of lactation. A circadian rhythm was observed for total corticosteroids in the blood of 3 out of 9 lactating and pregnant sows, while no circadian rhythm was observed in progesterone of the 4 pregnant sows. The disease complex mastitis-metritis-agalactia was discussed.

This publication has 2 references indexed in Scilit: