The 2020/21 breeding season is under way on autumn-calving Dairylink farms. The aim is to get as many eligible milking cows and maiden heifers served and in-calf as quickly as possible.

A key benefit of block autumn calving is the gradual improvement it brings to herd fertility because cows that are slow to get in calf leave the herd, or at least do not breed replacements.

Phase two Dairylink participants are now seeing that after a few years of having this approach to breeding, more cows are calved down and eligible for serving by the start of the breeding season each year. It has a snowball effect on herd fertility, as tightening and maintaining a compact calving profile gets easier over time.

With more cows coming on heat in a shorter period, heats should be stronger and easier to detect, which helps fertility performance too. It is easier to get many cows in-calf over a short period of time, rather than few cows in-calf over a long period.

Block autumn calving suits several Dairylink farmers because their cows have the genetic potential to respond well to concentrate feeding. The system allows cows to produce milk from good-quality silage and concentrates over the winter. By early spring, the bulk of the herd are settled in calf and over peak lactation and are therefore well suited to being turned out to grass once ground conditions allow.

Autumn calving also allows programme participants to capitalise on winter bonus payments which are paid in November and December for Lakeland suppliers.

On the young-stock front, a tight calving block means heifer calves form a uniform group which is easier to manage throughout the rearing process. This means more heifers will be at target weights and eligible for AI at the start of breeding the following year.

Farmer focus: Stephen Wallace, Seaforde, Co Down

There are six bulls in the flask for use on Stephen and Hazel Wallace’s Holstein herd this winter. The sires were selected from the UK-based profitable lifetime index (PLI) list. The main selection criteria on Heenandale farm were indexes for butterfat, protein and fertility.

Dairylink adviser Aidan Cushnahan recommended that breeding values for butterfat and protein should be at least +0.08% each, and the predicting transmitting ability for fertility should be at least five days.

He also included a requirement for at least 100kg under the breeding value for milk. This has been set relatively low because the cows on the Wallace farm already have genetic potential to deliver high milk yields.

Also, a less strict requirement for milk allows the best bulls for milk components and fertility to remain in the mix. When Aidan’s suggested criteria was applied, there were over 70 Holstein bulls in the PLI system that were available for narrowing down further.

Stephen’s bull team is slightly bigger than usual because the sires were selected from the genomic list of young bulls. Doing this will help reduce the impact if some of the bull’s breeding indexes eventually turn out to be lower than predicted.

An overview of the new bull team for use on Heenandale farm is outlined in Table 1. Most of the sires largely tick all the selection criteria recommended by Aidan.

It is interesting to note that Stephen’s bulls still have significant breeding values for milk. It shows that placing a priority on milk components and fertility does not mean that the index for milk comes down.

AI starts

“We started serving cows and heifers on Tuesday (1 December). All breeding work is contracted out where an AI technician comes once a day to check heats, touch up tail paint and serve cows,” Stephen said.

There are 110 early lactation cows going through the parlour at present and 60 were eligible for service at the start of the 2020/21 breeding season. There are 70 cows still to calve down. The bulk of these are due over the next four to six weeks, and late calvers will be finished up by the end of March.

The milking herd is currently averaging 32 litres at 4.13% butterfat and 3.30% protein. Between in-parlour feeders and blend through the wagon, average concentrate feed rate is 11.5kg. “We are feeding a mix of first-cut and third-cut silage at the minute. This is because first-cut was good quality but was a light crop, so we want to keep a consistent feed in front of cows for most of the breeding period,” Stephen explained.

Looking at young stock, there are 16 calves off milk already and another 15 are due to be weaned this week. “Calves are fed pasteurised milk for the first few weeks and then are transitioned on to milk replacer for the rest of the time,” he said.

Weekly round-up

  • Autumn-calving herds have started serving milking cows and maiden heifers.
  • Any cows that are slow to cycle are examined by a vet on most Dairylink farms.
  • Autumn-born calves are being weaned off milk replacer.