Ammonia Treated Straw Less Effective This Winter?

We are beginning to get calls regarding spring calving cows on ammonia treated straw.  The symptoms reported are low appetites and very solid dung like bricks.  This is the classical signs of rumen compaction due to the rumen microbes having insufficient energy and protein to reproduce.  The result is straw remains undigested in the rumen and gradually builds up until eventually the animal dies.  Unfortunately as the animal is effectively “stuffed” it does not appear to be hungry.

If you have stock on ammonia treated straw with little or no supplement and they are showing these symptoms then immediately supplement them or more precisely the microbes in their rumen.  Suitable supplements would be 2 kg of a high protein urea based syrup per head per day or 2 kg of a 50:50 rapeseed meal and barley mix.  With the cow having to meet nearly all the requirements of her calf from her own body reserves it is essential to get the rumen working ASAP.  To achieve this for the first 2 or 3 days the supplement should be fed twice daily ie a total of 4 kg per day.

The reason for ammonia treated straw being less effective this winter is almost certainly due to the tremendous weather at harvest last autumn and straw being extremely dry.  For ammonia treatment to be effective it is essential the straw is damp.

If you have any concerns please consult your local nutritionist or vet.

Basil Lowman, basil.lowman@sac.co.uk