When applying fertilisers such as superphosphate and basic slag this spring, remember to make sure animals don't ingest fertiliser with the pasture. Manufacturer's warnings and recommendations must be heeded because every year someone is caught out and loses cows.
Often the problem occurs because the owner has arranged the top dressing of the entire farm and the grazier is not informed when it will happen. As a result there is no way stock can avoid taking in fertiliser.
The animals actually die from damage to the kidneys and the abomasum or fourth stomach. It often looks as if affected cows have milk fever. Sometimes there is diarrhoea.
It's very important to wait until all the fertiliser is washed off the leaves of the grass before grazing. It is best not to top dress all the farm at the same time, in case there is no rain immediately after spreading. Keep a few breaks ahead of the herd clean until a decent rain has washed the grass clean.