Batching heifers boosts fertility
At Park Hall Farm, Tarporley, Cheshire, batching heifers into social groups has improved herd productivity and enhanced business performance.
Herd expansion forced the farm team to reassess their heifer management two years ago. Previously, heifers were brought into the bulling shed at the point of service and were AI’d straight away, explains dairy farmer Neil Roberts.
“It was probably a bit too much of a change and because of that, conception rates were being compromised,” he says.
As a result, Mr Roberts decided to change his system. Heifers are now batched at weaning and are slowly moved through a six-stage system in groups of 25 to ensure a smoother transition into the milking herd.
Step-by-step ration
Heifer calves are transferred from the calf house at two months of age into loose housing and are put on to a ration of ad-lib straw and starter nuts to maximise growth rates.
At 3.5 months they are then moved up a pen and on to a revised ration of ad-lib straw and 2kg a day of protein nut and are introduced to a TMR.
By five months they are transferred on to a full TMR ration until they calve, but move three more times within their groups into new pens before they reach 12 months.
“At 12 months of age they are transferred to cubicles and every single heifer gets a bolus and a heat-detection collar. Then they are left for four to five weeks before we serve them,” explains Mr Roberts. This gives them time to settle in.
Services
After this they are each served with a straw of sexed semen to maximise replacement rates. After two services to sexed semen if heifers are still not in calf they are served with conventional beef semen.
The conception rate is critical because of the cost of semen and the productivity lost when a heifer falls behind the target calving period. As a safety net, a pedigree stock bull is run with the heifers to keep calving interval and age at first calving tight.
“We PD between 34 and 40 days and then they go into new in-calf heifer cubicles and a little bit more straw is incorporated into the TMR to give more rumen fill.”
In total, heifers are given a maximum of eight chances of getting in calf before they are culled out of the herd.
Although this may seem quite a lot, Mr Roberts says heifers rarely reach this stage. Attention to detail combined with regular PD’ing and AI’ing every three weeks ensures heifers calve at no later than 28 months.
Batches
Heifers are assessed visually for group uniformity before being moved up with their batch into the new pen and any smaller heifers are left behind to catch up on growth.
Soon, the farm will be installing a new weigh crush, which can weigh heifers to give a more precise evaluation of performance.
“Consistency within the group for both size and growth is key. This should be achieved by hitting intake targets. But weighing will give us a true guidance to see if we are hitting these targets.
“It takes time to adapt to a different system; by batching them, animals are kept within the same social group and we only change their environment, which limits stress and improves conception rates.”
Managing heifers more effectively to ensure heifers calves at 24 months has paid dividends. So far, conception rates have improved by 11% to reach 72% (in 2011). Age at first calving has been reduced by 4.2 months to 24.1 months. Mr Roberts says it has also improved efficiency and reduced costs.
Benefits
“We are calving quicker so we get an extra calf and it reduces feed costs because heifers are putting milk into the tank quicker. Plus an additional four months of milk a heifer equates to a lot more milk in the tank,” he adds.
He says it also ensures heifers have a good start to be able to compete with the rest of the herd.
So far, the aim to increase the herd by 10% year on year by breeding replacements each year at 24 months of age is well on target.
But with expansion comes the need for additional space. To accommodate growing numbers of youngstock Mr Roberts plans to move them into a new shed, which will provide 130 new rubber-matted sawdust cubicles. Mr Roberts believes this level of cow welfare acts as the foundation stone in building healthy heifers, which are able to withstand management capabilities and calve at 24 months. “It costs so much to rear heifers that cow welfare is a no-brainer,” he says.
The benefits of calving at 24 months
- Younger heifers produce more milk in their lifetime
- The culling rate by five years of age can be 70% in heifers calved at 30 months old, compared with 20% if they are calved at 22 months
- A young heifer will have earned her keep by the time she is midway through her second lactation
- An animal calved at 30 months won’t have paid herself back until midway through her third lactation.
Figures provided by vet Hugh Thompson, Westpoint Vets, Dumfries
Park Hall Farm facts
- Milking 420 pedigree Holsteins, with 330 followers
- Yielding an average of 11,000kg a cow a year
- Year-round calving
- Age at first calving: 24.1 months
- Mastitis rate during first lactation: 5-10%
- Heifer conception rate: 72%
For a range of technical advice, facts sheet and farmer case studies on best practice heifer rearing, visit our Youngstock: Stop the loss campaign page
Find out how a heifer rearer and dairy farm undergoing expansion are ensuring heifers calve at 24 months
Read how diet and correct service timing can help get heifers in calf