8 August 1997

Limit over-conditioned cows and ease calving

CALVING difficulties are rising due to excess condition of cows in late lactation.

Many cows have had too much grass and are overfat and producers must, therefore, restrict energy levels fed, independent veterinary consultant Tony Andrews explains. "Condition scores at drying off should be between 2.5-3. But many cows are now over 3.5 and at this score fat will have been deposited around the birth canal, reducing space for the calf and causing slower calvings."

The added pressure on the calf can starve the brain of oxygen, resulting in sluggish calves for two to three days after birth. Where pressure is intense haemorrhaging can also occur leading to death.

As for the cow, when overfat shes more prone to milk fever, her fertility and immune system are depressed and infection is likely.

Dr Andrews says its easier to reduce condition while the cow is still milking. But if cows do reach the dry period at 3.5, stocking rates must be cut back so that grass intakes are held at about 5-6kg DM/head/day. &#42