Acidosis of the Rumen

Acidosis of the Rumen

Introduction

Rumen acidosis is a fast killing disease in ruminants that is caused by overeating with grains or ground feed.

In English, acidosis of the rumen is also called lactic acidosis, carbohydrate engorgement or rumen impaction.

Cause

When cattle, goats or sheep accidentally gain access to large amounts of grain or concentrate feed and eat too much of it the rumen contents turn acid, which can rapidly kill the animals.

Signs and Symptoms

After eating ground feed first signs appear faster than after ingestion of whole grain.

Visible signs appear more or less in the following order:

1. Bloat
2. Pain and kicking against the belly
3. (Sometimes animals that have eaten a lot of grain start drinking a lot of water)
4. No more feeding or ruminating at all, no rumen contractions
5. Staggering or not moving
6. Lying down and unable to rise, completely dull
7. Shallow rapid breathing
8. High temperature up to 41°C (esp. on a hot day)
9. Diarrhoea, liquid, sour smelling often with undigested grain visible

The larger the amount of grain ingested the more severe the acidosis is going to be. A cow or goat can die already at early stages of the disease. In cattle the time between overeating and death is 1 to 3 days, in goats it can be as short as 3 hours. Cattle may improve and then relapse 2-3 days later. Survivors may also go lame or abort (2 weeks later). - Overeating on grain is especially dangerous in animals that feed on pasture and do not normally receive grains or concentrate feed. In pastured animals 10kg of grain ingested over a short time is enough to kill a cow and 1kg can kill a goat.

Diagnosis

The most important is to react promptly when detecting a suddenly severely diseased animal and suspecting overeating with grain. Immediately confirm whether animals on the farm have had uncontrolled access to and eaten large amounts of grain or ground feed.

Treatment

Animals with milder acidosis and that are still able to stand and walk should be given magnesium hydroxide (400-500gr/cow, 4-5gr/goat) in warm water through the mouth (or by stomach tube). After giving the solution, massage the flank to mix the magnesium hydroxide with the rumen contents. If a vet is quickly available he can administer a 5% sodium bicarbonate solution and electrolytes intravenously. – In animals that show signs of recovery give only good quality hay and no grain at all for 3-4 days.

Severely affected animals may die any moment and should be slaughtered to salvage the meat.

Most animals that relapse after showing temporary improvement also die.

Prevention

Store grains and concentrate feed safely and out of reach for livestock. When supplementing animals with grain start by giving small amounts of grain in the evening after animals return from grazing and gradually increase the amount over two weeks.