As he continues a gradual switch from autumn to spring calving, the majority of milking cows on John Oliver’s farm are currently late into lactation and “free-wheeling along”.

Farming outside Limavady, Co Derry, John was operating a tight autumn calving system in 2019, but to make better use of grass in late summer and early autumn, decided to change the calving profile to spring.

While he is switching to spring, John is not going for a low-input system, but instead will aim to produce around 7,500l per cow from 2t concentrate fed.

The switch will not be fully complete until 2023, when John’s herd will start calving around 1 February. Next year, the first cows are due on 4 January.


Following the results of a recent scanning, John has 135 cows and heifers to calve in 2022.

Of these, 105 are due in the first six weeks and 128 should have calved by the first week of April. The first 50, calving over a three-week period, are all in-calf to sexed semen.

At present, there are 109 cows milking. Given that calving began in early November 2020, the majority of the cows are late in lactation and at an average of 290 days in milk. Over half the herd has gone past 305 days.

Average milk yield currently stands at 13l, 4.57% butterfat and 3.85% protein. The parlour is set at a 0.45kg per litre above 7l, meaning cows are receiving an average of 2.7kg per head of a 16% nut.

Dry off

The first group of 10 cows have been dried off this week. These cows are either low yielders, thin cows or animals that are lame, and they will be taken to hill ground normally grazed by Blackface ewes. John reckons he has sufficient grazing on this hill land to hold 100 cows for six weeks.

Later on in the season, dry cows will be housed and offered low potassium (K) silage made from swards that did not receive any slurry, so as to minimise the risk of milk fever post-calving.

According to John’s CAFRE Dairylink adviser David Mackey, the cows in milk on the farm are currently in good condition, with a score of 2.5 to 3.

“The vast majority of the cows do not need to gain condition during the dry period, so John must monitor that carefully and avoid cows going overfat. It is probably one of the main issues to be aware of, and avoid, when switching calving dates,” he advises.

Taking out low yielders at this stage should mean that the overall average yield of the herd increases to around 18l.


Cows had been grazing full-time with no silage buffer offered during milking for the last three weeks. However, a deterioration in ground and weather conditions has forced John to house the milking herd earlier this week and start feeding silage again after having passed over around 50% of the grazing platform in the last seven to 10 days. John plans to review conditions again early next week, to assess if any further opportunities for grazing exist.

This year’s grazing season has posed its own challenges for John. The last fertiliser application (30 units protected urea/ac) was applied at the start of September. With grass growth generally behind target during the summer, he was forced to house cows at night for 10 days at the end of August. This allowed grass covers to build, and cows had been out full-time since then.

However, John farms on light soils, in a high rainfall area and his land is 300ft to 600ft above sea level, so things can quickly change.

The milking platform is currently stocked at 2.64 cows/ha, and average farm cover is around 2,150kg dry matter (DM)/ha (approximately 650kg DM/ha in ROI system). John may graze around 10ac with calves, if he is unable to turn cows out again.

Alternatively, some of the heavier paddocks may be grazed off with ewes, as previous experience suggests that if too much grass is carried over, it can negatively impact on subsequent spring growth.

Laneways on the winter jobs list

Although ground conditions are holding up reasonably well, gaps in and out of paddocks are now seeing some damage.

Laneways are also starting to become more soiled and John has seen an increasing incidence of lameness since the weather turned.

He plans to tidy up lanes this winter, creating a constant gradient on inclines, a camber in places and diverting water away on other parts to avoid the surface being washed away. The biggest issues are at bends and where lanes become wider.

Ideally, John would like to use more woodchip on lanes, but on the inclines it is easily washed away, so there is little option outside of using quarry dust.

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