Target Condition Score At Calving

Calving is the most important time to have the cow in the correct condition. Achieving the correct condition score for the system of production will:

1. Maximise ease of calving and minimise if not eliminate difficult calvings and potential calf mortality etc.
2. Maximise colostrum quality and quantity to maximise calf health and productivity.
3. Maximise the subsequent fertility of the cow due to an easy calving. This will ensure no damage to the cow’s reproductive tract which coupled with maintaining her appetite etc will ensure she comes back in season rapidly post calving and settles quickly to the bull.
4. All of these critical advantages will be achieved at a reduced cost by carefully utilising the cows’ reserves of body fat to reduce her winter feed requirements.

What is needed at calving?

If cows are too fat or too lean calving difficulties will increase. With cows in too good a condition, above a condition score of 3, the problem is due to the excessive fat the cows are carrying. This begins to be deposited in the pelvic canal, narrowing the space available for the calf to be born. In addition fat is increasingly laid down as intra-muscular fat in the cow’s muscle. This reduces the efficiency of the muscles needed to push the calf out so cows tire very quickly before they have given birth.

The problem in very thin cows, below a condition score of 1, is many will go off their feet permanently and be too weak to give birth so they eventually die, even though a perfectly viable calf might be produced by caesarean section.

In general the leaner the cow the easier she will calve with perhaps the ideal being between a condition score of 1½ to 2. But to ensure the cow gets back in-calf again quickly then the leaner the cow at calving the better her feeding needs to be after calving to ensure she is gaining weight as rapidly as possible ie flushing her.

In comparison cows in better condition at calving, up to a condition score of 3, will get back in-calf rapidly even though they might be losing some weight ie fed a lower quality/cheaper ration post calving. (Providing of course that they also had an easy calving.)

Target calving condition scores

Autumn calving – 3 

The target for autumn calving herds is to have the cows fit at calving to reduce the amount/cost of feed needed to take them through the winter. In particular calving them in good condition allows the cows to lose a small amount of condition, around a loss of 0.25 kg per day, and still be highly fertile. The system is however dependent on having easy calving cows mated to easy calving bulls. Where some calving difficulties are expected the target calving score should be reduced accordingly.

Early spring calving – 2½ 

This is defined as herds where mating starts at or within 2 or 3 weeks of turnout. With little or no time on spring grass to regain condition, cows need to be in reasonable condition when mating starts at the end of the winter to maintain high herd fertility, and in particular achieve a compact calving period. Calving cows in February at a score of 2½ will also avoid the need for extremely high energy intakes post calving which would otherwise be required to improve their condition ready for mating, if they had been leaner at calving.

Traditional/late spring calving – 2 – 2¼ 
These are herds where mating starts at least one month after cows have been turned out. Energy intakes on ad-lib good quality spring grass will improve cow condition by more than half a score in just one month, effectively flushing them and maximising fertility. This allows full advantage to be taken of maximising ease of calving and minimising winter feed costs. It is however essential to closely monitor the condition of the herd to ensure cows are not below a condition score of 2 at calving to avoid the risk of downer cows.

Basil Lowman, basil.lowman@sac.co.uk