Good hygiene at calving and a vet check before mating for beef cows that have had assisted calvings will help get cows back in-calf more quickly and improve suckler herd performance.
Any cow that has had an assisted calving, twins, or a metabolic problem such as staggers is at risk of suffering uterine damage, or developing an infection, says Sussex-based vet Kate Burnby of Livestock1st.
Stillbirths, retained cleansing, or a visible discharge also affect a cow’s ability to cycle and get pregnant again.
These at-risk cows may get back in-calf late or not at all, ending up barren. Infection can prevent fertilised eggs from reaching the uterus due to blocked fallopian tubes, or it can destroy the uterus lining and prevent implantation.
“The uterus is designed to expel anything that has entered it from the outside during the calving process.
Problems occur when an assisted calving introduces more infection.
When a cow is under the weather because she’s too thin, too fat, or stressed, her immune system won’t work properly and clean up any infection,” explains Miss Burnby.
“When the uterus is full of pus a cow won’t cycle as prostaglandin isn’t being released from the uterine wall.
Studies have shown that cows with metritis take another two to six weeks before they conceive again.”
The ideal time for a vet check is four weeks after calving, she says.
By this time, the uterus should be back to its normal shape and size.
A check at this stage is a good time to catch problems before mating.
Cows that are dirty and potential problem breeders can be treated with antibiotics or prostaglandin to clean them up and get them cycling normally again.
Herds which have more than 2% difficult calvings or where hygiene isn’t up to standard for assisting at calving may see more than average numbers of dirty cows.
Herds with more than 10% at-risk cows plus poor fertility can benefit economically from a vet check, believes Miss Burnby.
“Weigh it up against the cost of keeping an empty cow – upwards of £500/year.
Getting more cows back in-calf quickly pays for itself.
But a routine fertility check should tie in with a whole management package – a single vet visit isn’t going to answer all of your fertility problems,” she says.
Suckler producers need to be stricter on culling barren cows and watch for those which extend the calving pattern, believes SAC Vet Services’ Colin Mason, based in Dumfries.
“In a heavily subsidised industry, a cow had ample time to get back in-calf.
But producers now need to be aware of the optimum calving block and the financial losses incurred from going over it,” he points out.
Herds with both spring and autumn calving groups tend to move cows that are hard to get back in-calf between the two groups, or accept a prolonged calving period.
“But now producers need to consider the cost of feeding that cow for the extra six months she isn’t in calf,” he adds.
While incidence of metritis in beef cows is not well recorded, Mr Mason says it is related to difficult calvings.
“The more often a farmer has to stick his hand in to calve a cow, the more cases of metritis.
Aiming for a big calf increases the risk of calving difficulties and a dead calf is lost income for the year.”
Instead, Mr Mason suggests producers select sires on estimated breeding values for calving ease and shorter gestation length.
Far better to breed smaller, but viable calves that are up and drinking quickly, he explains.
“Research shows that 200-day weights are no different for these calves compared with animals that are larger at birth.”
These calves rarely show any problems with scours or neonatal illness, adds Mr Mason.