What Factors Influence Reproduction Beyond the Voluntary Waiting Period?17 June 2014
Reasons for infertility in cattle are hugely varied, although new research has narrowed down the causes.
The team at the Dairy Cattle Reproduction Council writes that Swedish researchers recently investigated the factors affecting a reproductive performance indicator at the cow level adjusted for herd reproductive management strategy—in this case, the voluntary waiting period. The study, published in the April Journal of Dairy Science, found that the chance for pregnancy was lower for:
- Cows with severe problems at claw trimming compared with cows with no problems at trimming (only for second- and higher-parity cows)
- Cows with a record of reproduction-related disease (For example, metritis, endometritis, etc.)
- Cows of second- and higher-parity with records of dystocia compared with cows with no record of dystocia
- First-parity cows in the group with the highest milk yield compared with first-parity cows in the group with the lowest milk yield
- Cows of third- and higher-parity in the group with the lowest milk yield compared with cows in higher yielding groups
- Cows with a twin birth compared with cows with a single birth
The researchers also noted that the chance for pregnancy decreased when the milk fat-to-protein ratio increased and as the somatic cell count increased. They concluded that factors that are known to affect reproductive efficiency also affect the chance of cows being pregnant 30 days following the voluntary waiting period.