Hypomagnesaemia in sheep
Hypomagnesaemia, also known as grass tetany or grass staggers, is a condition that affects sheep, particularly during the first few weeks after lambing. This condition is caused by low levels of magnesium in the blood, which can lead to severe health issues and even sudden death. Sheep cannot store magnesium in their bodies, so they require a constant dietary supply to meet their needs. This makes them particularly vulnerable during periods of rapid grass growth, such as in the spring, when magnesium levels in pasture can be low.
Symptoms and Diagnosis of Hypomagnesaemia 🩺
Sheep suffering from hypomagnesaemia may show signs such as trembling, especially in the facial muscles, and an inability to walk or a stiff-limbed gait. They may also collapse and experience tetanic spasms, where all four limbs are rigidly extended. Unfortunately, death can occur very rapidly, sometimes being the first indication of the disease. Diagnosis is typically confirmed through blood tests showing low magnesium levels.
Treatment of Hypomagnesaemia 💊
Immediate treatment is crucial to prevent death. Affected sheep can be treated with a combined injection of magnesium and calcium, administered intravenously. This is often followed by a subcutaneous injection. Recovery can be rapid, but relapses are possible, so repeated treatments may be necessary.
Prevention of Hypomagnesaemia 🛡️
Preventing hypomagnesaemia involves ensuring that sheep have a consistent supply of magnesium, especially during high-risk periods. This can be achieved by supplementing their diet with magnesium oxide, often mixed into concentrates. Providing high-fiber diets can also help by encouraging rumination and salivation, which aids magnesium absorption. Additionally, avoiding stressful situations and ensuring adequate sodium intake can help stabilize magnesium levels.
Additional Tips
- Consider using magnesium boluses or supplementary forage to increase salivation and reduce disease risk.
- Be cautious with potassium-rich fertilizers, as high potassium levels can interfere with magnesium uptake.