The effect of pre-partum milking on the transfer of immunoglobulin into mammary secretion of cows.
The significance of local effects associated with mammary involution on transfer of immunoglobulin and especially on the selective transfer of IgG1 into mammary secretion of cows approaching parturition has been determined. This was carried out by measuring the changes in the concentration of IgG1, IgG2, IgM and IgA in serum and mammary secretion of 5 cows in which two mammary glands were milked continuously (twice daily) during the period preceding parturition, while the other two glands were allowed to undergo normal involution. In the secretion of unmilked glands of all cows there was a substantial increase in the concentration of IgG1 as cows approached parturition. In contrast, the increases in the concentration of IgG1 and in the selective index for IgG1 of milked glands were either virtually non-existent (1 cow) or generally reduced in magnitude and delayed in time of onset (4 cows). It is clear from the results that continued milking of a mammary gland throughout pregnancy tends to maintain milk production in the milked gland and at the same time reduces the massive selective transfer of IgG1 into secretion of that gland.
D000818:Animals; D002417:Cattle; D003126:Colostrum / Q000032:analysis*; D005260:Female; D007070:Immunoglobulin A / Q000032:analysis; D007071:Immunoglobulin A, Secretory / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007136:Immunoglobulins / Q000032:analysis*; D007743:Labor, Obstetric; D007774:Lactation; D011247:Pregnancy; D011270:Pregnancy, Animal; D013997:Time Factors
D007070:Immunoglobulin A; D007071:Immunoglobulin A, Secretory; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins