Serum immunoglobulin concentrations in suckled calves and dairy-herd calves

Morbidity and mortality of the young calf represent a major cause of econom ic loss for beef producers. This study was undertaken to quantify serum imm unoglobulin concentrations in (1) suckled calves from a single herd and sir ed by either Charolais or Limousin bulls out of cows that were either Charo lais (n = 16), Limousin x Friesian (n = 64) or Simmental x (Limousin x Frie sian) (n = 10) and (2) purchased (at auction marts) calves, from dairy herd s, with unknown colostrum history and consisting of Charolais x Friesian (n = 61), Limousin x Friesian (n = 39), Belgian Blue x Friesian (n = 9) and H olstein x Friesian (n = 73). Purchased calves were approximately 28 days of age and were bucket-fed a standard milk replacer. Serum samples were colle cted on day 0 (day of arrival) and on day 28 after arrival at the research centre. Serum samples were collected from the suckled calves at 28 and 56 d ays of age. Serum immunoglobulins (IgG(1), IgG(2), IgA and IgM) were measur ed quantitatively by single radial immunodiffusion. The zinc sulphate turbi dity (ZST) test was performed on all serum samples. The IgG(1) serum concen trations and ZST units were significantly higher in the suckled calves, wit h no significant differences in IgG(2), IgA and IgM concentrations, when co mpared with the purchased calves at 28 days of age. At 56 days of age, seru m IgG(1) and total Ig concentrations were significantly higher in suckled c alves than in purchased calves while serum IgA and IgM concentrations tende d to be higher in purchased calves. In summary, suckled calves had higher s erum IgG(1), total Ig and ZST units than purchased calves.