How to maximise the fertility of your heifers

How do you maximise fertility to get heifers to calve-in at 24 months? As a follow-on from the Youngstock; Stop the Loss Campaign, Aly Balsom speaks to a contract rearer and a farmer who rears his own to find out how they do it

Margins are being squeezed from all directions, so having that 30-month-old pregnant heifer munching on precious feed stocks and taking up valuable space is even more wasteful than ever.

It makes sense to get her growing and calving into the herd as soon as possible so she starts paying her way.

In fact, vet Hugh Thomson of Westpoint Vets in Dumfries says ensuring heifers calve at 22-24 months versus 30 months will have long-term benefits on performance.

“This younger heifer will produce three times more milk in her lifetime, mainly due to reduced culling risk,” he says.

“Research has shown that culling rate by five years of age can be 20% in 22-month-old heifers versus 70% in 30-month-old heifers.”

“A younger heifer will also have paid herself back by the time she reaches mid-way through her second lactation, whereas an animal calving at 30-months-old will only start paying for herself mid-way through her third lactation.”

Two producers have recognised the benefits of calving-in early, and give their thoughts on how they hit fertility targets:

The expanding herd

Herd expansion can mean there’s little room for error when getting heifers in calf, but how do you try and maximise pregnancy rates?

For Dumfries and Galloway producer John Gordon, a synchronisation programme has helped get heifers in-calf at a time that suits him, and allowed him to calve them into the herd in manageable batches.

“We get good batches of heifer entering the herd at the same time, which means they hold their own better,” he says.

Mr Gordon introduced the programme to Boreland of Borgue in Kircudbright about a year ago. With heifers at grass, heat detection can be a problem, so ensuring they all come into heat at the same time makes it easier for him to serve in batches.

The target is to increase the herd from 200 to 300 cows in the next year, with 80 in-calf homebred heifers due to calve-in over the next eight months. A further 50 bulling heifers are due to be served in the next two months.

With so many heifers coming into the herd, Mr Gordon believes it is crucial to get stock calving at two years and under.

“Space is an issue for us, and expansion of the herd needs to be as quick as possible, rearing as many heifers as we can,” he explains.

“Calving at 24 months or under is really important; we have found that lifetime days in milk increase and overall costs reduce.”

First services are done off a synchronisation programme, so there is no requirement for heat detection initially (see key consideration box). The programme runs as follows:

• A progesterone device is inserted into the vagina 10 days before the allotted service date
• Heifers are injected with prostaglandin on the sixth day after insertion
• On the seventh day after insertion, the progesterone device is taken out
• Heifers are served 56 hours after the device has been removed
• Achieving up to 82% conception rate with conventional semen, and averaging 65-70%.

Heifers calve from 22 months of age, with a herd average of less than 24 months, and careful management from birth means many animals are big enough to serve at 13-14 months.

“We assess bulling heifer groups regularly for size and fitness to breed – age is not really taken into account,” Mr Gordon says.

Mr Gordon cites early calf management as the foundation for ensuring heifers reach the right size at service. “Everything is scrutinised from colostrum quality, health, temperatures, weigh banding and blood sampling to assessing antibody levels,” he says.

A weigh band is used to monitor growth rates once a week until weaning and then heifers are run over a weigh scales. In total they are monitored eight to 10 times from birth to service.

“We have regular visits from our vet, and by weaning, the calves are averaging 0.9kg/day. From then, they never seem to look back,” says Mr Gordon.

And to ensure heifers are on a rising plane of nutrition prior to service, the amount of 18% protein blend is increased by 0.5kg/head/day from three weeks prior to service.

Synchronisation – key considerations

• Synchronisation removes the need to rely on heat detection
• Can be beneficial where time for heat detection is limited
• Having a group of heifers calve together creates a socially stable group
• Any returns will come in a fairly set period
• The success of synchronisation still relies on management and ensuring heifers are healthy and at the correct body-condition score
• Conception rates can be reduced by 5-10%, but when management is in place, conception rates can be as good if not better than if no programme was in place.

The contract rearer

Heifer rearer Andrew Brisbourne of Painsbrook Farm, Shrewsbury, Shropshire, goes that extra mile to ensure his heifer-rearing system is as finely tuned as possible.

From regular weighing and wither height recording, to collating bulling records from automated heat detection, coupled with three time daily visual checks, everything he does is targeted at getting stock to calve at 24 months.

Mr Brisbourne contract rears heifers for producers Rob and Steve Cope who farm at nearby Market Drayton and has up to 430 heifers on farm at one time, ranging in age from three months to 23 months.

“On average, heifers are calving back into the herd at 24.5 months,” says Mr Brisbourne. “The Copes want to maximise profit a heifer and the quicker they calve-in, the better.”

For Mr Brisbourne, regular monitoring is the crux of the system, with weights recorded roughly every time heifers move sheds.

“I monitor because it provides a better service and I need to weigh to ensure feeding is as finely tuned as possible – I don’t want them getting too fat,” he says.

Wither heights are measured when heifers arrive on farm at three months old, again when they move into the Ai group and when they leave.

“The aim is to get heifers to about 400kg by 14 months,” he says. “Generally heifers are 91kg and 88cm at three months old and 584kg and 140cm when they’re in-calf at 23 months.

“I can’t afford for them to lose too much ground if I want them to calve at 24 months,” he says. “Ideally they need to achieve 0.83kg DLWG. My last batch did 0.81kg over the 20 months they were on farm.”

Overall, Mr Brisbourne’s heifer-rearing policy is as follows:

• Animals usually arrive on farm in groups of eight to 12 and remain in this group until nine months of age
• At nine months old they move into a cubicle shed so they are trained to this system
• At 11-12 months (one month before service), they move into the Ai group so they can settle before service and get used to the ration and their behaviour can be calibrated with the automated heat detection system
• Signs of bulling are still visually observed three times a day, although Mr Brisbourne believes automated heat detection is valuable because it is difficult to know when heifers will come bulling.
• Vet visits every week on routine to keep on top of any issues
• Stock are Ai’d twice and then swept with the bull (bulls are selected by the Copes)
• Achieving 70% conception to first service, rolling average
•  In the summer, heifers are put out to grass, except for the Ai group
• A TMR of wholecrop triticale, grass silage and liquid protein is fed with varying levels of protein depending on age of stock. The younger calves also receive pellets and ad-lib hay.

Vet view:: Hugh Thomson – top tips for getting heifers in-calf

1) Calf management – ensuring heifers are on track to calve at 24 months starts from birth. Good colostrum quality and preventing disease is crucial.

2) Monitoring growth rates – regular monitoring is important to identify areas for concern. The pre-weaning stage is critical – get them through this ok and they’ll never look back.

3) Nutrition – don’t over-complicate things. Be selective about what you feed and access protein levels at key times. Ideally, heifers should be body condition score 2.5 to 3 at service.

4) Protect against infectious diseases – ensure worming protocols and vaccination programmes against key disease such as BVD are in place.

5) Synchronisation timings – when using a synchronisation programme, have clear protocols in place and stick to them. If you don’t, you won’t get the full benefits.

6) Reduce stress – ideally heifers should move to the facilities where they will be served two to three weeks prior to service. All vaccination programmes should also be finished two to three weeks prior to service.

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