Animals will readily eat 15kg to 20kg of meal if given the opportunity. The consumption of excess carbohydrate-based concentrates leads to a build-up of lactic acid and a condition known as ruminal acidosis. The rumen’s microflora is a delicate balance of bacteria and microflora. When grain overload takes place, certain bacteria predominate, producing the excess lactic acid.

The speed of onset of clinical signs and severity of the condition is directly proportional to the quantity of concentrate eaten. Usually between 12 and 36 hours, the animals become wobbly, uncoordinated and appear drunk. They stop eating and become dull and depressed. The rumen becomes bloated, causing pain and grinding of the teeth. The gut draws water into it, causing scour, and the body quickly becomes dehydrated. The animals will lie down and resemble an animal with milk fever, with heads thrown against their flanks.

Diagnosis of cases is usually based on history and clinical signs – there is no time to take samples. Treatment is difficult and, in severe cases, very unrewarding. The goal is to correct the dehydration and acidosis by giving oral and maybe intravenous electrolyte solutions. Calcium and multivitamins can also be of value.

Unfortunately, even in animals that are saved, there is a considerable reduction in thrive, as the rumen remains constantly inflamed, the liver can be full of abscesses and they will often subsequently suffer from chronic lameness due to laminitis.

Prevention is most definitely better than cure in these cases. Obviously, feed bins and stores must be securely locked up.

Also when increasing the amount of concentrates being fed to cattle, this must be done on a graduated basis in order to allow the rumen develop microflora to deal with the increasing amounts of carbohydrate being eaten. The importance of good-quality roughage, such as straw, cannot be underestimated when feeding large amounts of concentrates.

Sean Coffey works at Mulcair Vet Clinic, Newport, Co Tipperary, part of XLVets, a group of practices working together to achieve a better future for agriculture in Ireland.