A nationwide study of colostrum revealed that 45 percent of all samples had a total plate count of greater than 100,000 colony forming units (cfu) per ml, a level associated with calf illness. Only 23 percent of refrigerated samples had less than 100,000 cfu/ml. This may be compared to fresh samples that had 67 percent under 100,000cfu/ml.
In his latest issue of "Calving Ease," Sam Leadley with the Attica (N.Y.) Veterinary Associates looks at three suggestions to put the breaks on bacteria growth in colostrum:
- Alternative #1: Feed the colostrum before these environmental bacteria have an opportunity to grow. When bacteria are introduced into colostrum they do not begin to grow immediately. A short period of time, bacteriologist’s call this the “lag phase,” is needed for the bacteria to modify their new environment in order to reproduce. Thus, if colostrum is fed roughly within one - half hour after it is collected the bacteria wi ll not yet have had time to replicate.
- Alternative #2: Lower the temperature of the colostrum. The general relationship is that generation time (time to double) gets longer as the temperature goes down. For example, at cow body temperature coliform bacteri a in colostrum double in about 20 minutes. At 60° this doubling or generation time is about 150 minutes. At the setting of most refrigerators (40°) generation time is over 24 hours.
- Alternative #3: Consider using a food - grade preservative. An economical choice is potassium sorbate. The most practical form for on - farm use is a 50 percent solution.