Ewes face danger of milk fever

Waimarino Bulletin, Volume 1, Issue 16, 20 September 1983, Page 16

Ewes face danger of milk fever

With lambing underway in the Waimarino, the danger of ewes getting milk fever is greatly increased. Ewes are most at risk two weeks before and two weeks after lambing. Untreated ewes will die within 6-36 hours of going down. Milk fever, or hypocalcaemia, is a disease of pregnant and lactating ewes and also occurs in cattle. Milk fever comes about when the calcium level in the blood falls below normal. This , happens when the demands for calcium are-so great that not enough can be absorbed through the gut or reabsorbed from the bone. Stress situations, such as a break or change in diet, a sudden change of feed, temporary starvation, droving or yarding all increase the demand for calcium. Some plants such as green cereal crops and sorrel also

depress blood calcium levels. Affected animals are usually found sitting with their legs underneath or behind them. Early cases may simply show a stilted gait. Mild bloat may be present and there is commonly a greenish-white nasal discharge. Milk fever symptoms similar to sleepy sickness and the nasal discharge are the sure identifiers of milk fever. A calcium injection is the simplest way to treat milk fever. Affected ewes should recover within about 30 minutes of this treatment. Calcium solution is an irritant so the needle must be sterile and the wool should

be cleared around the area to be injected. Carelessness at this stage could cause an abcess, Ministry of Agriculture and Fisheries animal health division recommends the following precautions against milk fever. First, avoid putting ewes in stressful situations especially in the high-risk period around lambing. Second, restrict access to sorrel and green cereal crops. If this isn't possible, keep a close eye on sheep on these crops. Third, seek veterinary advice if large numbers of sheep develop milk fever or if they fail to respond to treatment.