The occurrence of calving difficulty varies between seasons and properties.
Calving difficulties (dystocia) can contribute heavily to production losses.
Between 50 and 60 per cent of calf losses are due to difficult calving.
Less noticeable losses due to calving difficulties include delayed return to heat, poor conception rates, and increased labour, veterinary and medicine costs.
Many calving difficulties can be avoided by doing the following:
- Mate heifers and small cows to easy-calving bulls. The bull’s Estimated Breeding Value (EBV) will provide a useful guide;
- Ensure heifers have reached their critical joining weight, join heifers for a maximum of six weeks, and maintain optimal nutrition during pregnancy to ensure that heifers are well grown at calving; and
- Monitor body condition score (BCS) and target calving cows and heifers to be in BCS 2.5-3.0 at calving. This should not vary by more than 0.5 BCS during pregnancy.
It is important to keep in mind if a certain cow fails to conceive or has problems calving, there is a good chance she will repeat this later in her life.
When assisting cows at calving, make sure you provide adequate time for a cow or heifer to calve prior to interfering.
However, monitor closely as early intervention can help prevent a difficult calving and calf deaths.
It is crucial you recognise your limitations and level of competence and be prepared to call for veterinary assistance when it’s required.
For further information, contact your local veterinarian or Agriculture Victoria veterinary or animal health officer, or in NSW your Local Land Services.
— Dr Jeff Cave
Agriculture Victoria district veterinary officer