Effects of maternal nutritional restriction and cold stress on young calves: absorption of colostral immunoglobulins.

Fifty-seven newborn calves delivered from heifers fed rations either adequate or restricted in protein or metabolizable energy were housed in cold (1 C) or normothermic (21 C) environmental chambers for 3 days to determine the effects of maternal nutritional stress and cold exposure on ability of the animals to absorb colostral immunoglobulins (Ig). In general, the serum Ig concentrations in the newborn calves from dams fed rations restricted in protein or metabolizable energy and the concentrations in sera of the respective calves from dams fed adequate protein or metabolizable energy were similar throughout the 3-day period of observation. Likewise, the serum Ig concentrations in the cold-exposed calves were similar to those in the calves kept at normothermic temperature. An exponential increase in mean serum concentrations of IgM, IgG1, and IgG2 occurred between 3 and 6 hours of age; the values continued to increase, but at a slower rate after 6 hours and reached a peak by 12 hours of age. Then, IgM and IgG2 decreased until 48 hours, after which time they increased, but IgG1 varied only slightly from the peak at 12 hours and then increased. With one exception, data indicated that neither the maternal dietary restrictions or the cold exposure imposed on the calves caused significant (P greater than 0.05) differences in absorption of colostral Ig when compared with that of the respective calves from dams fed adequate diet or the calves kept at normothermic temperature.