Grain poisoning in livestock
Jillian Kelly, District Veterinarian, Coonamble
Grain poisoning is number one on my list this week, with lots of cases around the district.
Many animals are on high cereal grain diets, many eating wheat. Wheat is one of the highest risk grains for poisoning as it is a small grain (so large surface area for rumen bugs to act) and it is high in starch.
Grain poisoning occurs when the starch is broken down rapidly by rumen bugs, which causes the pH of the rumen to drop. Acid producing bugs love this drop in pH so they flourish, while the good bugs die off. This perpetuates the problem with even more acid production, which spills over into the blood stream causing clinical signs and eventual death.
Animals that are introduced to grain slowly are given time for their rumen bugs to adapt and deal with the acid production from the starch digestion, and they will be fine on grain rations. While this has been done in many cases, the recent stormy weather has been playing havoc with appetites and we have seen grain poisoning in mobs of grain that have been eating grain for months.
Interestingly, when a storm approaches and the barometric pressure drops, ruminants appetites decrease and they go off their feed. They also won’t eat much while the storm hits, preferring to take shelter instead. Once the storm passes and the barometric pressure returns to normal, they rebound eat (larger amounts, after a period off feed) and grain poisoning occurs.
Signs of grain poisoning are lameness (sheep and cattle get laminitis or foundered), abdominal pain (hunched up, grunting, head twisted to the side), scouring and large amounts of grain in the faeces. So check your mobs daily, be mindful of self-feeders and if there is any disruption to animal behaviour, such as stormy weather, close the feeders down a bit or provide plenty of hay.
For advice on animal nutrition, please talk to your local District Vet.