- Lowering the number of difficult calvings improves cow and calf health.
- Measuring calving traits like gestation length, birth weight, and stillbirth rate are easy tools to monitor calving issues.
- Calving ease scores are effective in monitoring calving difficulty on farms.
Problems during calving can delay dairy cows reaching peak production and may impair the ability of a cow to calve again.
- First lactation cows that have a difficult time giving birth may have increased labor and veterinary costs.
- There is an increased probability the cow may not survive.
- Calves that are born with difficulty are more likely to be stillborn or develop a digestive or respiratory disease.
Why record calving traits?
While good management practices may help minimize calving problems, recording calving traits may also be valuable.
- Consider genetic evaluations for calving ease of potential service sires especially for mating virgin heifers.
- Using different sire breeds may reduce costs associated with difficult births.
- Recording birth traits on the farm can help producers improve cow and calf health and reduce financial loss.
Calving traits to record
- Gestation length: the date of successful insemination subtracted from the date of calving.
- Birth weight: measured within 12 hours of birth.
- Stillbirth: recorded as the calf either living or dead within 24 hours of birth.
Gestation length and birth weight usually are connected. Cows with a longer gestation length usually have heavier calves at birth. The breed of cows has an impact on calving traits as well.
- ProCROSS breeding uses Montbéliardes, which makes for heavier birth weights than Holstein.
- Grazecross calves have Jersey traits, which means they are usually lighter than Holstein calves.
Calving ease score
Calving ease is another important tool to measure the success of reproduction programs. Calving ease is measured on a five-point scale, each number corresponds with the level of difficulty required to birth the calf.
- Calving ease score 1: quick, easy birth with no assistance.
- Calving ease score 2: over two hours in labor, but no assistance.
- Calving ease score 3: minimum assistance, but no calving difficulty.
- Calving ease score 4: used obstetrical chains.
- Calving ease score 5: extremely difficult birth that required a mechanical puller.
Stillbirth and calving ease scores may be entered in any dairy management software program for tracking individual dairy herds.
Reviewed in 2020