Researchers in the UK recently studied the effects of calving ease on the fertility and production of 50,000 first lactation Holsteins and their 10,000 Holstein heifer calf offspring. The study had two main objectives:


Estimate the effect of a difficult calving on the subsequent first lactation production.


Estimate the effect of a difficult birth on the calf as a mature animal.

Based on these objectives, researchers reported the following results in the November 2011 issue of Journal of Dairy Science:

Cows requiring vet-assisted calving required 0.7 more services to conceive, needed an additional eight days to reach first breeding and had a 28-day longer calving interval.

Milk losses were significantly higher in cows with calving difficulties, producing approximately 4.4 pounds less milk per day than cows without calving difficulties.

Calves born as a result of a difficult calving produced 1,565 pounds less milk in their first lactation compared to calves born without difficulty, showing a lifelong effect of difficult calvings.

Click here to read the Journal of Dairy Science abstract.


Source: DCRC January 2012 newsletter