This condition is also known as parturient paresis as it occurs around calving time (parturition time). It occurs or is caused by a drop in blood Calcium level caused by extra Calcium drain from the blood into the milk at calving coupled with the inability of the cow to change her metabolism rapidly enough to keep blood Calcium level up. It is most common in breeding cows and especially older, high producing cows and again more commonly in autumn calving cows. In sheep, milk fever or lambing sickness as it is commonly known can occur at any time during the final six week of pregnancy.
It is frequently associated and triggered by stressful events such as housing, gathering for vaccination and periods of harsh weather. Therefore rather than being a simple dietary deficiency, milk fever occurs due to failure in the homeostatic mechanisms that regulate blood calcium levels. This is a condition all farmers should look out for and prevent as dry season or winter is approaching hence feed and nutrient deficit is about to come but mostly because as a farmer one needs to condition their animals well so that they have a smooth calving time without complications. Increased risk occurs with cold, wet conditions, poor nutrition prior to calving,age and breed.
– Loss of appetite
– Slight drop in temperature
– Inactive digestive tract
– Cold ear and dry muzzle
– Dull eyes, starring
– Dilated pupils
– in-coordination or unsteadiness when walking (staggers)
– slight muscle spasms/ tremors
– cow may fall down or lay down and be unable to rise
This could happen in three stages
I. Standing but wobbly.
II. Down on chest and drowsy; sick animal may be found lying on her sternum with her head resting on the shoulder.
III. Down on side and unresponsive.
If left untreated, the animal becomes comatose and dies within a day of the appearance of the first signs.
Effective treatment can be achieved if it is administered in time. Treat promptly with slow Intravenous infusion/injection of 600-800 ml of Calcium borogluconate.
Oral administration of 100g of ammonium chloride for 204 days and high calcium boluses (75g) within 8 hours of calving.
Prevent by stimulating cows calcium mobilization before calving
Feed a transition diet three weeks to calving, include anionic salts.
Avoid feeds high in potassium, sodium and calcium in the springer diets.
Increase dietary calcium immediately after calving.
Avoid fat cows at calving
Administer vitamin D injections 2-8 days before calving for cows with a history of milk fever.
Limit calcium intake during the dry period.
Preventative measures for sheep should include a suitably balanced mineral mix in the late pregnancy ration and the avoidance, as much as possible, of undue stress for ewes that are heavy in lamb.