Effect of induction of parturition on immunoglobulin content of colostrum and calf serum

Abstract

Thirty-four pregnant crossbred beef cows were injected with prostaglandin F 2 alpha (PGF group, n = 11), dexamethasone (DEX group, n = 11), or saline (control group, n = 12) on Day 270 of gestation. Immediately after calving, all colostrum was milked from each cow. A sample was taken, and the remainder was fed to that cow's calf within one hour of birth. Serum was collected from each calf at 0 and 24 h of age. Immunoglobulin G (IgG) content of colostrum and serum was determined with commercial radial immunodiffusion plates. The data from four PGF cows that did not calve until after 140 h post injection were excluded from the results. Mean (± SD) volumes (ml) of colostrum were 2086 (±1148.4) for the PGF group, 1336 (±583.7) for the DEX group, and 2404 (±1140.7) for the control group. Mean (± SD) concentrations (mg/dl) of IgG in colostrum were 6017 (±3351.2) for PGF, 10285 (±5370.7) for DEX and 10766 (±5098.3) for the control group. Mean (± SD) total quantities of IgG (g) in colostrum were 133.9 (±120.03) for PGF, 134.1 (±96.67) for DEX and 235.6 (±147.22) for the control. IgG concentrations were very low or were not detectable in serum of all calves prior to administration of colostrum. Mean (± SD) concentrations (mg/dl) of IgG in serum of calves at 24 h of age were 1469 (±905.8) for calves from PGF cows, 1819 (±1289.8) for calves from DEX cows, and 3317 (±1888.2) for calves from control cows. Calves from control cows had significantly more IgG at 24 h than calves from PGF cows or DEX cows (p<0.05). Calves born to cows induced to calve early may be at an increased risk of failure of passive transfer and so should be monitored for IgG concentrations.