Monday, March 25, 2013

They Do Great Until I Wean Them
 
Well, back in USA at the Attica Vet Clinic.  But my head is still in HaverfordWest, Wales at the farmer meeting last Friday.
 
Six different farmers appeared to have the same problem. Their calves were growing well until they were weaned. Then at weaning they seems to stop growing or maybe even lose weight.
 
What did they have in common? Three were spring block-calving herds that fed nearly ad lib milk up to 8 to 10 quarts of milk a day. Three were continuous calving herds with automatic computer feeders feeding at least 8 quarts of milk powder a day. The calves were getting a lot of nutrients from milk!
 
All six had observed that while in full milk ration their calves began eating starter grain only when four or five weeks of age. And, even then, they did not eat much grain.
 
We spent a few minutes reviewing the processes of rumen development. 
  • special microorganisms are needed in the rumen to ferment a mixture of water and grains thus digesting both proteins and carbohydrates. 
  • how the fermentation of grain (or very young grasses) releases butyric acid leading to the growth of rumen papillae.
  • rumen papillae development takes roughly three weeks from when regular grain consumption begins - this provides enough surface to absorb nutrients. 
Then we talked about how they weaned their calves off of milk.  The block-calving herds either stopped milk feeding rather abruptly in either one or two days. The computer-feeder herds had a three or four-day step-down weaning period.
 
The bottomline in all six cases is that not enough time was provided on a reduced milk-feeding program before weaning to provide for increasing amounts of grain intake leading to adequate rumen papillae growth. As a group we tried to come up with several practical ways to cut back on milk feeding volumes. 
 
Great group of farmers. Great Welsh lamb meat pies for lunch. Yum.    

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