The number of first calvers that make it through to their second lactation is a critical figure in evaluating the success of the management of newly calved heifers.
That’s the view of leading Cheshire-based vet and independent dairy herd consultant Neil Howie, who says adopting a specific management protocol for newly calved heifers – rather than turning them straight into the main herd after calving – has both a long and short term influence on a heifer’s health, production and fertility.
“There are a host of reasons why newly calved heifers benefit from a separate management regime. But just what that regime should be and how long it should last depends on the facilities that are available on the farm and the standard of the stockmanship,” says Mr Howie.
“If dairy farmers are aiming to calve heifers at under 30 months we’ve got to remember that these animals are still growing; trying to produce a lot of milk, and need to get in-calf again. They are metabolically different from the mature cows in the herd by having to do those three things at the same time while being a younger animal.
“So if you accept they are different to cows surely they demand a housing and feeding system that recognises that difference.”
Vet Neil Howie’s blueprint for first calvers
- Have individual calving pens that are well bedded
- Make sure then pens are close to the area where they have been prior to calving
- Move heifers to a post-calving transition area after 24-hours, providing the heifer is steady on her feet and eating
- Transition area to be bedded (preferable to cubicles), but with very close attention to hygiene to avoid environmental mastitis
- Transition diet – easy on protein but the best quality fed and forage available –starch-based energy source
- Make sure cows have adequate trough space and easy access to clean water
Mr Howie recognises the provision of separate accommodation and management for a specific heifer group is often the biggest hurdle for milk producers.
“To do this without creating other challenges within the management system on the farm remains the question most dairy farmers have to address,” he says.
On units where providing specific management for newly calved heifers is being considered, one of the most relevant questions concerns the length of time this needs to be applied.
In some herds freshly calved heifers may be run separately for a period of weeks until such time as they are considered to be settled into their lactation and over the stress of calving. In other herds the decision may be taken to run the first calf heifers as a group for their entire first lactation.
“Having a larger transition area is one way of providing a system for newly calved heifers which means they could stay in there for the whole of the first lactation.
“They could, if necessary, share this accommodation with freshly calved cows and because the transition ration for a mature cow is similar to that for a growing heifer the feeding regime would be straightforward.
“The level of stocking within this accommodation needs to be at 80% of the feed space available to ensure heifers can feed at the trough without competition. It’s something of a compromise, but at least it means these heifers don’t have to cope with the hierarchal stress they would encounter if moved immediately into the main herd.”
Mr Howie says injury is one of the biggest threats to newly calved heifers moved into the main herd immediately after calving. “Calving is a bruising experience and even if they’ve experienced cubicles previously it’s still a challenging environment when there are bully cows to cope with.
“Even just finding and competing for feed where they have never found it before can lead to a significant risk of physical injury. They are often too stressed to lie down with all the issues that has on their welfare.”
The stress imposed on newly calved heifers that are forced to cope with the rigours of the main herd has significant repercussions on health, performance and fertility, believes Mr Howie.
“There is massive evidence that metabolic stress and physical stress in the first three to four weeks after calving has a huge negative effect on fertility.
“If heifers are successfully managed through the first 30 days after calving and are metabolically well and physiologically well they are undoubtedly more likely to reproduce when you want them too.”
Mr Howie asks: “How many farmers know how many of their first calvers actually calve again? How many heifers calve down again within the average calving interval of the herd?
“These are critical figures that reveal so much about the management of freshly calved heifers.”
‘Grouping is an essential part of herd management’
Having run his newly calved heifers in a specific group for almost seven years, Cheshire milk producer John Allwood is convinced it’s an essential part of his herd management.
The 500-cow herd at Huntington Hall, near Chester, is split into two groups – one on a 45-litre ration and the other on a 35-litre ration. All first-calf heifers are run in the 35-litre group.
The milk-sold herd average is just under 11,000 litres, but heifers currently make up 42% of the herd.
“We’re feeding the heifers for 32 litres and the rest of their ration is for growth,” says John Allwood, who aims to calve his heifers at 24 months.
The 35-litre diet comprises grass silage with an energy blend, protein blend, wheat straw, Trafford Syrup, Trafford Gold and minerals.
Heifers coming up to calving are moved into the close-up dry cow group – one of two groupings for dry cows. They stay in this pre-calving group for four weeks and are then moved into a calving box at the onset of calving.
Usually within three hours of calving each heifer is moved to the transition sand cubicle area, where newly calved cows are also housed.
“We ketone test all cows and heifers as they calve so, assuming they have no high ketone levels and are hitting 30 litres, we’re ready to move them into the 35-litre heifer group.
“They stay in this group for the entirety of the first lactation and are dried off from there,” says Mr Allwood.
He says he likes his heifer system, because it ensures the freshly calved heifers are in a socially stable environment.
“They aren’t being challenged by larger cows so they have every opportunity – both nutritionally and socially – to develop to their full potential. Running similarly sized animals together removes confrontational issues and we don’t get heifers knocked about by bigger cows.
“We aren’t overcooking their rumen as we do with a 45-litre cow diet; the ration they are on is tailored to match their output and their liveweight gain.”