The first cows will start calving on John Oliver’s farm near Limavady, Co Derry, at the end of this week. There are 20 cows due to calve down by the end of August and another 35 will have joined the milking herd by the end of September.
John has tightened his calving profile and brought the start of calving forward, so that more cows will be able to produce milk from autumn grazing for longer. He has also invested in improving grazing infrastructure to help extend the grazing season by constructing new laneways, installing more drinkers and adding extra entry points to paddocks.
With more cows calving down in shorter time, John has been getting calf accommodation organised so that it is as labour-efficient as possible.
The plan is for calves to be put into individual pens for the first three days. The pens were purchased last year and are made from PVC boarding and plastic slats. This means there will be no labour requirement with bedding and the pens should be easy to wash and disinfect between calves.
The main calf house has been re-arranged this year so that each pen holds 15 calves instead of five. The new setup also means each calf has 2.5m2 of space, compared with 2m2 last year. A walkway has access to each pen and the bigger groups should mean it takes less time to feed calves using teat feeders.
Calves will be fed twice a day, with each calf getting 850g/day of milk replacer. A scoop has been marked which holds enough milk replacer to cover five calves for one feed. This will be made up to 2l-2.5l/calf.
Drinkers have been installed in each pen and creep-feeders will be used to give calves access to concentrates once they enter the group pens. A stack of straw bales will be put in each pen and bedding comes from the top bale. Calves will also be able to eat straw from the bottom bale, which removes the need for filling racks in each pen.
John can streamline the calf-rearing process with larger groups because the compact calving block means that calves should be fairly uniform. In some herds with a spread out calving profile, the range in age and weights of calves means large groups in calf sheds would not be possible.
The tight block also means that although the calf house will be busy during autumn, John will have most calves weaned off milk replacer by January and they will be ready for turnout once conditions allow in February.
Dry cows
There were 37 late-lactation cows still milking on the Oliver farm when we visited last Friday. Cows are averaging 12l at 3.96% fat and 3.68% protein from 1kg of concentrates.
Dry cows are currently batched into three groups, depending on how close they are to calving. The far away group is grazing hill ground which starts at the edge of the milking platform. This ground is mostly used for grazing John’s 100 Blackface ewes, but rough grasses on the hill provide adequate forage for cows post drying off.
After 30 days, dry cows are moved into a different part of the hill and are supplemented with 1kg of rolled barley and 200g of minerals for around three weeks. As cows get close to calving, John moves them down to small paddocks beside the yard and he tries to calve cows outside if conditions allow.
Colostrum protocol
He usually lets calves get colostrum by sucking the cow. If a calf is slow to suck the cow they are brought into the calving pen, where a new headlock gate can be used to help get the calf to suck.
This protocol probably stems from John’s days in suckler beef farming, before he converted to dairying. However, he maintains that calves that suck the cow have a better immune status than calves that receive colostrum through a tube or bottle.
Last year, some calves were zinc sulphate turbidity (ZST) tested where a score above 20 units is generally considered as adequate colostrum immunity. John said calves that were tubed had lower ZST scores than calves that sucked the cow, with the highest recording a score of 40 units.
Late calvers
The bull was kept with the milking herd longer than initially planned this year, and 10 cows that originally scanned empty are now due to calve down in late December and January.
John was planning to sell these cows as springers because they are calving later than he wants for his block autumn-calving system.
However, improvements to soil fertility mean John is growing more grass and he wants to increase overall farm stocking rate above 2.0 LU/ha.
Ideally, he would like to buy in 10 cows or heifers that are due to calve in the next few weeks and then sell off the late-calvers as springers or fresh-calvers around Christmas. However, slurry storage and housing space is tight, and John won’t be able to keep both newly bought in cows and later-calvers for a few months over the winter. He is now considering keeping these late-calvers and selling them after their next lactation as culls.