I received the bacteria culture information from a client having sporadic severe scours problems among a small number of young calves. Previous cultures of "as-fed" colostrum had bacteria counts varying from almost no growth to well over 100,000 cfu/ml.
We agreed to sample several batches of colostrum like this:
1. Directly from collection bucket immediately after milking colostrum.
2. Directly from refrigerated nursing bottle.
3. Directly from nursing bottle with warm colostrum just before feeding the calf.
1. All the collection bucket samples were reasonably low - under 5,000 cfu/ml.
2. All the refrigerated nursing bottle samples were still under 20,000 cfu/ml.
3. Wow! Warm colostrum samples were all over the place. The lowest under 10,000cfu/ml with the highest too numerous to count (TNTC) - estimated at 250,000cfu/ml.
What was going on? I discovered that their protocol called for the worker that found a cow in labor to put two refrigerated bottles of colostrum into a water bath to warm. The objective was to have warm colostrum ready to feed about the time the cow delivered the calf.
Part of the time this protocol worked just fine. The cow's labor was reasonably short and the colostrum did not sit warm waiting to be fed very long. Part of the time this protocol did NOT work just fine. The cow's labor was longer than predicted and the colostrum sat and sat and sat and grew more and more and more bacteria until it was bacteria soup.
We agreed that while it was a good idea to feed colostrum promptly after birth the urgency was not so great that there was time to warm the colostrum after the calf was born.
The revised procedures seem to be working better. The number of calves with very severe diarrhea has dropped to nearly zero.