The Effect of Pasteurization of Colostrum on Absorption of Immune Globulins by Calves

total protein intake. The estimated percentage of ruminal bypass of feed protein was only slightly higher in cows fed extra-heat SBM compared to the control group (28.8 vs 27.8 percent). Therefore, based on these data and those in the feeding trial, it appeared that the extra-heat SBM (PDl-IO) used in this trial was not heated extensively enough during processing to make it a high bypass feed protein source. Nevertheless, the values obtained on percentage of feed protein bypassing the rumen of cows consuming a 60 percent concentrate ration at the rate achieved in this trial are of interest. These data will be useful as reference points for future trials in which extent of degradation of different sources of feed protein will be estimated.