Serum immunoglobulin concentrations in suckled calves and dairy-herd calves

Morbidity and mortality of the young calf represent a major cause of economic loss for beef producers. This study was undertaken to quantify serum immunoglobulin concentrations in (1) suckled calves from a single herd and sired by either Charolais or Limousin bulls out of cows that were either Charolais (n = 16), Limousin x Friesian (n = 64) or Simmental x (Limousin x Friesian) (n = 10) and (2) purchased (at auction marts) calves, from dairy herds, with unknown colostrum history and consisting of Charolais x Friesian (n = 61), Limousin x Friesian (n = 39), Belgian Blue x Friesian (n = 9) and Holstein x Friesian (n = 73). Purchased calves were approximately 28 days of age and were bucket-fed a standard milk replacer. Serum samples were collected 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 days of age. Serum immunoglobulins (IgG(1), IgG(2), IgA and IgM) were measured quantitatively by single radial immunodiffusion. The zinc sulphate turbidity (ZST) test was performed on all serum samples. The IgG(1) serum concentrations and ZST units were significantly higher in the suckled calves, with no significant differences in IgG(2), IgA and IgM concentrations, when compared with the purchased calves at 28 days of age. At 56 days of age, serum IgG(1) and total Ig concentrations were significantly higher in suckled calves than in purchased calves while serum IgA and IgM concentrations tended to be higher in purchased calves. In summary, suckled calves had higher serum IgG(1), total Ig and ZST units than purchased calves.