Milk fever (or hypocalcaemia) in cows
- Milk fever in beef and dairy cows occurs most often in high producing older cows within 48 hours of calving, but it can occur several weeks before or after calving.
- Ironically predisposing factors include high calcium or phosphorus in the diet in late pregnancy.
- Feeding acid or anionic salts in the weeks before calving can help prevent the disease.
- Affected cows are often just found down, characteristically with the head swung round beside the body.
- Early signs can include reduction of appetite with a preference for roughage, a drop in milk production, reluctance to move and after a few days ‘drunken’ behaviour, walking in circles aimlessly, with vigorous licking, great anxiety and trembling.
- Commonly, dairy cows develop a mild form of the disease, in which the only signs are a drop in milk production and infertility problems. This has recently been called the “sad cow syndrome”.
Milk fever (or hypocalcaemia) in ewes
- In ewes, milk fever occurs in older ewes in the weeks around lambing (from 6 weeks before to 8 weeks after lambing).
- The disease is often brought on within 24 hours of a sudden stress. This might be yarding, transportation, forced exercise, very bad weather or insufficient feed.
- Sometimes a sudden change of feed, eg a move to lush pasture, will trigger outbreaks.
- The signs are restlessness, trembling, staggering, depression and recumbency.
- It is characteristic to find ewes down on their chest (rather than on their side) with their hind legs extended out behind them, and head down and extended forward.
- There may be a discharge from the nose, they may become bloated and they usually abort dead lambs.
- Affected ewes may just be found dead.
- Treatment of milk fever is by injection of calcium solutions at the first sign of problems.