Since joining the Dairylink programme in 2018, a key focus for Stephen and Hazel Wallace has been to tighten up their herd into an autumn calving profile.
Milking around 200 cows on Heenandale Farm outside Seaforde in Co Down, the bulk of the herd is now being calved between September and December.
To date this autumn, around 75% of the herd has calved, and with sexed semen used, there are 100 heifer calves on the ground, along with six Holstein bulls.
The remainder of the calves are beef bred.
The last of the stale cows were dried off towards the end of November, with all dry cows now inside and on a diet of round bale silage and 2kg per head of a dry cow blend.
The silage was grown specifically for dry cows, so there was no potassium (K) applied to the sward in the form of fertiliser or slurry.
Over the last few weeks, Stephen has been recording heats in calved cows ahead of breeding, which started on 1 December. It means the first cows will calve around 10 September 2022.
Sires have been selected using the UK Profitable Lifetime Index (PLI), with each sire required to have a Predicted Transmitting Ability (PTA) of at least 100kg for milk, 0.08% butterfat, 0.08% protein and a positive fertility index.
Bulls selected for this season include Denovo 3150 Generate, Bomaz Platt, Pine-tree Butch, Bomaz Episode and Denovo 3159 Gander.
When it comes to getting autumn-calving cows in calf, nutrition is key, points out CAFRE Dairylink adviser Judith McCord.
“In early lactation, nutrition plays a significant role in getting cows to cycle, express normal heats and conceive when mated. We want to get enough energy in to avoid excessive negative energy balance or metabolic problems such as ketosis, but at the same time, not end up with issues linked to digestive upsets, etc. It is a careful balance in high yielding dairy cows,” Judith says.
The Total Mixed Ration (TMR) on the Wallace farm currently includes both first and/or second-cut silage, fourth-cut silage, along with 7.5kg per cow per day of a concentrate blend (see Table 1).
The TMR is formulated to support maintenance plus 25l, with heifers on maintenance plus 21l. Outside of any minimum and maximum feed rates, additional concentrate is then fed at 0.4kg per litre above these levels in the parlour.
Post calving, cows on the Wallace farm build up from 2kg of concentrate in the parlour on day one, to 8kg by 28 days-in-milk.
From day 28, cows are fed to yield to a maximum of 10kg per head, with the minimum feed level set at 4.5kg per head out to day 100.
For heifers, they build up from 2kg at calving to 6kg per head by 28 days-in-milk. From day 28, heifers are fed to yield to a maximum of 8kg, with the minimum feed level also set at 4.5kg per head out to day 100.
As shown in Table 2, the first-cut silage is reasonably good (ME of 11 MJ/kgDM), while the second cut is excellent (11.8 ME). Both silages are in the same pit.
A second pit contains fourth-cut sitting in front of third-cut, which is yet to be analysed. The fourth cut was harvested in unsettled conditions, so it is quite wet, and that has driven the intake value below 100.
The proportions of the different cuts of silage within the TMR are likely to change as the winter progresses, although the plan is to ensure that the first/second-cut silage is included throughout.
The overall estimate of crude protein in the diet (both forage and concentrate) is 16.3%.
Around 40 of the earliest born calves this autumn have now been weaned, and were estimated to be eating around 2kg per head of concentrate by the time milk was fully withdrawn.
Stephen and Hazel feed fresh milk to calves, passed through a pasteuriser. The pasteurisation process should be effective at eliminating the disease challenge from the likes of salmonella and E. coli, and means that waste milk is not discarded on the Wallace farm.