Maximising returns from growing heifers

Phil Kinch from Buscot Wick Farm, along with independent nutrition consultant Hefin Richards, explore the principles of maximising growth of the growing heifers.

What determines heifer rearing “efficiency”?

• Age at first calving is a fairly easy metric – average gives a starting point, but you also need to look at the percentage that fall within a target acceptable range. The average could be 24 months but there may be some animals calving very young to make up for animals which are slipping through and calving much later.
• In a block calving herd, the priority is to get animals calving at the start of the block. This ensures the calves in two years’ time will also be calving at the start of the block. Additionally, if there is any slippage in fertility in subsequent lactations, animals will remain in the block.
• Mortality and culling – how many heifers that are born make it into that first lactation and beyond?
• Reproductive performance – this is critical in a block calving herd. When you hit the day where you want to get animals in calf, it’s imperative that most get in calf in that first 3 week window. Heat detection, preparation, service technique, consistency of diet will all play a part.
• Target weight at service and calving – the danger of focusing on age at first calving is that it can sometimes compromise the performance of those animals because they’ve calved younger, but we’ve compromised on liveweight at first calving. This will have an impact on production and potentially survivability. It’s very important when calving at around 24 months that you’re hitting target weights right the way through the process, at service and when calving.
• Cost from calf to calving varies tremendously. Generally block calving herds costs are somewhat lower, possibly because calves and heifers are reared within tightly aged groups so it’s easier to target nutrition and manage it more closely rather than a moderately-sized all-year-round (AYR) herd where there tends to be a bigger spread at every stage. Variation largely between farms depending on performance, mortality, and cost of managing the feeding, housing and handling those animals from calf to calving.
• Milking herd performance and survivability into lactation 2 plus - we tend to look at heifer rearing efficiency beginning when the calf is born and ending when she enters the milking herd, in reality if we do that we may be missing a trick because if we have compromised milking herd performance and survivability that is not economically. To really assess the heifer rearing programme, we need to look at how those animals go on and performance and survive within the herd.

Key areas for improvement across all herds

Heifer rearing and performance of heifers is a key performance indicator for block calving herds

Use sexed semen on heifers and earliest cows bred

• Allows a greater number of heifer calves born earlier in the block – need to calve in at 24 months not 22.5

Achieve good early DLWG

• Has a big impact on lifetime performance
• Health, nutrition, environment – higher cost per day but higher feed conversion efficiency (FCR) and lifetime gains
• Colostrum management
• Good quality calf milk replacer or milk and good intakes
• Good quality starter with quality protein and good intakes

Post-weaning transition

• Maintain quality starter intake to maintain 0.8kg/day +
• Grouping – take every opportunity to even up heifer group when weighing, regroup according to size and performance
• If feeding TMR, look at protein supply and energy sources, minerals and vitamins are important, look at overall cost as cheapest option may not be the best nutritionally

Weigh and adjust feeding and management at all key stages

Key stages of heifer rearing

New-born to weaning

• Colostrum intake – critical for performance, health and survivability
• Milk/CMR – quality of quantity of product fed needs to be fit for purpose
• Daily light weight gain (DLWG) – the gold standard measure to assess if you’re achieving what you need to be
• Weaning weight – gives us a good indication of how effective the calf rearing regime is
• Health – a lot of this comes back to colostrum intake and management over the first few days; respiratory health is a challenge especially in autumn calving herds

Weaning to pre-breeding

• The aim is to achieve smooth transition through weaning
• Target starter intake to maintain DLWG
• Adjust feeding to introduce more forage – but don’t rely too much on forage too soon
• Maintain target DLWG on forage-based diet depending on:
  • Forage quality – forage analysis to give an indication if it’s delivering what we need it to and allows you to balance and supplement diet if necessary
  • DM intakes – feed space, feed hygiene, availability, comfort of eating, making sure space is adequate as animals are growing
  • Concentrate use – targeting around forage quality and feeding something suitable, e.g. if forage is low in protein, feed a high protein concentrate
  • Grazing management – in block calving herd there are two good grazing opportunities before heifers calve; weather conditions and grass availability will impact level of growth through the grazing season

Heifer rearing costs

• Costs generally lower for block calving herds as calves are managed in groups – age of calving is more tightly managed
• As age at first calving increases, cost of heifer rearing increases – first thing to look at if heifers are costly on your farm
• As time spent at grass increases, cost of heifer rearing decreases

Why and when should I weigh heifers?

Why?

• To identify strengths and weakness in the system – what areas are working and what needs further attention
• To identify average and range of DLWG – average allows you to see if system is predominantly on track, range will identify animals that need managing differently
• To aid decision making on management
• Group or sub-group management decisions – whole group may need additional feed if weights on average are below target
• Performance vs cost decisions – if you are ahead of target, you may be able to reduce costs

When?

• At birth – gives a starting point for each individual animal
• Weaning – gives an indication of how successful the calf rearing stage has been
• (6 weeks post-weaning – tells us how good we are at managing weaning process)
• Turnout – gives us a barometer of winter-feeding regime
• (Mid-season – valuable particularly in autumn block-calving herd to make sure we’re still on track)
• Housing – relatively close to breeding stage, could be combined with pre-breeding
• Pre-breeding, Turnout – once in calf, (Mid-season), Calving

Calf and heifer feeding regime at Buscot Wick

• Calves only picked up once a day so rely on cows feeding suckled colostrum – although this year have been trying to tube at least 2 litres of high-quality colostrum into replacement heifers
• Following this, calves are kept in groups of 7/8 and fed non-pasteurised whole milk from day 1-5 in Wyedale feeders
• Calves are moved onto calf machine circa day 5 and fed high quality milk replacement (Volac Blossom 23%/18%) up to day 65, have access to chopped straw and high-quality cake during this time
• Post wean, calves are moved onto Dairy TMR (with 2kg calf starter cake initially) until turnout
• During mid-late spring, calves are turned out to pasture in one group, and are later split into two groups later in summer
• Weather permitting, everything is housed mid/late October to get them used to the TMR pre-mating, and start serving mid-November
• Heifers are given one service of sexed semen, another service of conventional semen then bulls put in
• Stay on heifer TMR until turnout in April, usually stay in one group for management ease until 2-3 weeks pre-calving when they are put with the mature cows and moved onto a transition diet

Key weight targets for Buscot Wick

• Minimum target to double weight by weaning but aim for 2.5x by weaning – potentially delay weaning a little further to give animals chance to reach 100kg
• Turnout around April – aim to reach 220kg by this time to give a good, well-grown heifer to go out to grass – animals will be fairly robust to graze and achieve good grass intakes
• Achieving this is down to a smooth transition off milk through weaning, good nutrition, good housing, and good health through the first winter
• From turnout to housing, achieving DLWG of 0.75 on average will give a 370kg heifer at housing
• Look to maintain 0.75-0.85 DLWG through winter on heifer TMR to have a 500kg + animal by turnout and a 600kg animal by calving
• At 12 months, animal should be 50% of mature weight at a minimum and 90% of mature weight at calving

Recommendations to improve heifer rearing at Buscot Wick

Invest in suitable weighing and recording software to identify areas to improve performance or reduce costs

• It’s critical to hit these targets to software would show a big return and help improve management and efficiency of heifer rearing as well as milking herd performance

Review colostrum protocols – assess colostrum status of heifer calves

• Relying on suckling is a bit risky especially in early season when there are a lot of heifers calving down with heifer calves – bearing in mind how critical colostrum intake is
• Could get some blood tests done to assess current colostrum status and formulate a plan based on this

Investigate impact of bovine respiratory disease (BRD) on performance of individuals

• Worth looking backwards at animals that have failed to perform in milking herd –either failed to breed or didn’t grow well – and seeing if there is a link between individual cases or BRD in the rearing phase
• Come up with a strategy with the vet to manage this – vaccinations, managing housing, etc.

Review suitability of milking TMR (high starch, protein quality) on first winter – convenience vs performance/cost

• High performance milking diet – be careful having young heifers on this diet ad lib.

Group based on LW and DLWG

• Identify and support poorer performers to pull them back into line and ensure the maximum number of heifers hit target

Assess grazing based on DLWG – mid season weight gives time to correct to pre-breeding

• Might be adequate for 60-70% heifers so may be easier to manage the smaller, later-born 30% different to pull those into line

Post breeding – target higher DLWG for late season born, early season calving heifers

Ensure that transition/fresh cow nutrition strategy is in place in time for earliest calving animals

• Variation in cow size, dominant cows will generally beat first lactation heifers in critical transition time
• Look at transition in terms of space, facilities and nutrition