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Having switched over to exclusively spring calving in 2021, the milking herd on Frank Goodman’s Carrickmacross farm is coming near the end of their lactation.
There are 102 cows going through the parlour. The herd was housed full-time on 1 November to allow covers to be built on the grazing platform ahead of the spring.
With the first cows due to calve from 1 February 2022 on, these animals will be among a group to be dried off at the end of this month.
There are some thinner cows in the milking group, and Frank intends to give them an extended dry period, but in general he is happy with the body condition score (BCS) of the herd.
Previous on-farm research in Northern Ireland (NI) has highlighted the importance of having cows at a target BCS of 2.75 to 3 at drying off. Cows that are over fat (BCS over 3) at calving eat less post-calving and mobilise more body tissue. This can lead to various health problems, and lower fertility.
Alternatively, the study showed that thin cows at drying off (BCS under 2.5) are more likely to be culled within the first 60 days of a subsequent lactation.
However, perhaps the main conclusion from the work was that it is very difficult to get cows to gain body condition during the dry period, even if concentrates are offered over the entirety.
So it is important to dry cows off in the target condition score for calving.
Extra feed
According to Dairylink CAFRE adviser Michael Verner, where cows are below target BCS in late lactation, farmers should consider offering an extra 2-3kg of a high-energy concentrate at this stage.
“But the feed must be targeted at individual cows. Other cows won’t need it at all, so it is not a policy that should be applied across the herd. When we talk about inefficiency in concentrate feeding on farms, it often comes down to over-feeding of late-lactation cows,” says Michael.
On the Goodman farm the intention is to feed first-cut silage plus 1kg per head of straw to dry cows. In the last six weeks pre-calving, these cows will also be offered 1kg per head of a specialist dry cow nut.
With good records in place, Frank is also in a position to operate selective dry cow therapy. Any cows with an average SCC of under 150,000, and no cases of mastitis in the past three months, will not receive antibiotic dry cow tubes, and instead, just teat sealant will be administered.
Current diet
Ahead of drying off, Frank is currently feeding an average of 3.2kg per head of a 16% protein dairy nut.
Despite being housed full-time since the start of the month, cows are still being offered zero-grazed grass, along with approximately 22kg per head of baled silage. With a limited land block of 12ha around the yard, Frank has zero grazed an outside land block since the spring, with cows kept inside at night. He tries to cut grass when it is dry, although at this stage of the year, it is increasingly marginal whether it is a good use of his time.
All youngstock are still grazing, and will probably be housed in early December.
Silage
Once bales are used up, Frank will move over to his main pit of first-cut silage. He also has a good crop of maize silage taken off 10 acres. The intention is to start feeding maize at a rate of 5kg per head from the start of March 2022.
However, Frank is also considering increasing the area of maize grown in 2022, which would mean it is available as a buffer year-round.
“Offering 5-10kg of maize silage that has a dry matter of 30%+ could especially have a role in the spring when conditions can be up and down, and when grass protein is at its highest level,” suggests Michael Verner.
“We can get protein levels in spring grass of over 20%, which is more than the cow needs. The low protein and high starch in maize will definitely help to counter that,” he adds.
Calving
Looking ahead to the spring, Frank expects to calve down 112 animals, including 36 heifers.
Breeding began on 24 April, with cows served exclusively using AI. Heifers were inseminated for six weeks and then a bull was introduced, but according to Frank, the bull had little work to do.
Cows have been pregnancy tested and the herd has a slightly high empty rate of 14%, although with the number of heifers coming through, there was scope to ignore any late breeders.
Empties will be culled along with older and poorer performing cows.
Milk solids produced per day is a key measure used by Frank when identifying culls.
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