How a heifer rearing unit works successfully at scale

Economies of scale have allowed a contract farming business to maximise efficiency by sending replacement heifer calves from three of its dairy herds to a single, dedicated rearing unit.

Farming Partners has set up a system delivering 600 calves every spring to a heifer rearing farm at Over Garrel, near Lockerbie, in Dumfries and Galloway.

Reared by youngstock manager Sara Williamson, the calves can rotationally graze, negotiate electric fencing and walk along cow tracks to grazing before returning to their respective herds ready to calve at 22 months.

See also: 12 tips on rearing heifers to last longer

Because all three herds operate the same spring-calving, grass-based system, the heifer calves are born with just an eight-week spread in age.

This means they can be treated as one, making routine preventative treatments, feeding and tasks such as knockdown disbudding, easier.

Dedicated team

Sara says there are both benefits and challenges from rearing youngstock in such large numbers.

She operates with a dedicated team of two staff (and is on the lookout for a new assistant manager), which does not have to do any milking, or other cow-related work.

“We only do youngstock, but it can be a full day organising groups and fencing, and if we get breakouts, we can easily lose an hour,” she says.

At peak times, additional help comes from three agricultural students, and staff from the three dairy herds.

Her biggest challenge is sickness.

“If calves are inside, it can go through them very quickly; you have to be on the ball with so many calves, otherwise you could miss things.

“The same goes for managing [worm control] outside, such as taking routine dung samples.”

Shed setup

Purpose-built shed © MAG/Shirley Macmillan

The farm has two purpose-built calf sheds for rearing herd replacements, erected five years ago. Each holds 390 calves in pens of 13, either side of a central feed passage.

Every pen is split into a straw-bedded section and slatted feed passage, with calf-sized water troughs and hay racks, situated at calf height.

There is an open ridge for good ventilation plus ventilation tubes. Pens have a white board to record any treatments using a colour coding system.

Calf preparation

Up to 40 calves arrive at the unit each day in spring, having received colostrum with a Brix value of at least 22% in their first two days.

Blood tests about a week after arrival will confirm their passive transfer success from colostrum. (Beef-cross calves arrive at the same age, are housed separately, then sold at 14-21 days privately to a local rearer.)

On arrival, calves are given an intranasal vaccine for respiratory syncytial virus (RSV), iodine on navels (checked daily), and weighed.

Although they eventually return to their own herds, calves are mixed and reared according to weight gain and health status.

The key to getting so many young animals to settle in quickly is to give them plenty of bedding straw, says Sara. This allows them to snuggle down, nest and sleep.

She ensures staff are trained to be calm, and no shouting is allowed. “We also have to be very patient, as we teat-train them as well,” she adds.

Good hygiene throughout is essential – water troughs, for instance, are cleaned out twice a day to encourage calves to drink.

Feeding is based around two litres of warm (38.5C) milk replacer, given twice a day in a slick operation.

“We use a 13-teat feeder that hooks on the pen gate. We feed the youngest calves first, then the older ones, using a 50-teat trailer to mix milk and cart it.

“Once they are fully trained to teat feeding, it takes us 45 minutes to feed one shed,” Sara explains. “We watch calves drink, bed them up, clean troughs, fill racks and scoop pellets in.

“We don’t keep going in and out of pens, so we are not bringing in disease. We muck them out after five weeks, spread lime and bed again until turnout.”

Stepped-down weaning is usually at eight to 10 weeks of age, when calves have doubled birthweight and are eating 2kg a head of concentrates a day.

The diet then comprises concentrates, and straw fed in racks filled three times a day, plus straw bedding. At weaning, Sara groups poor performers together for extra feeding.

Grazing management

Grazing season finishes in October © MAG/Shirley Macmillan

Turnout is weather dependent, usually from mid- to late-April. For a transition period, concentrates and straw are offered in IBCs in the paddock.

Sara allocates a daily 3kg dry matter (DM) of grass for each calf. They graze on 24-hour moves – 12 hours if wet, to reduce trampling – with 120 calves in a group, and R2s in groups of 200.

To help with parasite control, Sara also runs a leader-follower grazing round with R1s in front.

“It’s important that we train them to graze well. We have fenced tracks, but you have to train calves to move
– we start by going in front with a snacker and a bike behind,” she says.

Housing is by the end of October in pens of 35 on slats (150 better-conditioned R1s go onto fodder beet on the run-off block).

The winter diet is 5kg DM/day of clamp silage, plus 0.5-2kg of soya or rapemeal, depending on calf weight.

Calves are housed in pens of 35 © MAG/Shirley Macmillan

In January, a mineral bolus and fluke drench are given before a second grazing season starting in April. This time, allocation is 9kg DM grass, without concentrates.

“We serve 200 heifers to natural heat and 400 to synchronised heat and get them in daily for insemination by a technician. Then we pregnancy scan at 35 days and use sweeper bulls for 10 weeks,” she says.

From September, the home farms arrive to vaccinate heifers and freeze brand them.

Sara transitions in-calf heifers onto fodder beet and baled silage on the run-off, and they return home during Christmas and New Year, ready to calve from 1 February.

Clamp silage is fed in the heifer’s first winter at 5kg a head dry matter © MAG/Shirley Macmillan

Average rearing cost

Mass youngstock rearing benefits from scale and efficiency and, although Sara is paid a daily headage rate, financial savings are shared across the partnership’s nine Scottish herds.

The average heifer rearing cost is £1,500. Yet further improvements aim to grow more grass (the farm produces 10t DM/year) and set farm-specific growth rates.

Sara has also replaced the weigh crush with a platform and electronic tags to be able to easily record weights, track growth rates, and, eventually, relate it to herd performance.

On arrival, calves weigh 35-40kg, and leave in-calf at 400kg for a crossbred, 370kg for a Jersey cross, and 430kg for a Friesian-type.

“We weigh every two weeks until weaning, then every five weeks until breeding.

The idea of the platform is that the older calves can just run across it,” she says, adding that some mature cows have now been weighed, and the plan is to base growth targets on them.