Mammary immunoglobulin transfer rates following prepartum milking

Abstract

Colostrum formation is thought to occur slowly over an extended period (4 wk) prepartum. Furthermore, colostrum formation is highly variable among cows in total volume, IgG1 concentration, and mass obtained at first postpartum milking. Recent work has suggested that a rapid transfer of IgG1 to secretions may occur if animals are milked prepartum. Our objective was to establish the concentration, mass, and mass transfer rates of IgG1 in multiparous Holstein cows (n = 11, parity = 3.6 ± 1.1) milked prepartum (−74 to −1 h) and again around 4 h postpartum. Blood concentrations of IgG1 were very low (<1 mg/mL) in 7 cows at prepartum milking and did not decline following prepartum milking. Cows showed variability in the capacity to recover total volume, IgG1 concentration, and IgG1 mass. Three groupings of cows were considered based on the time between the 2 milkings (prepartum + 4 h postpartum): long-time (−74 to −54 h, n = 3), medium-time (−25 to −17 h, n = 4), and short-time (