Two NI dairy units were showcased in a virtual summer meeting of the British Grassland Society last Wednesday, held in conjunction with the Ulster Grassland Society and Fermanagh Grassland Club.
Brothers Wesley and Albert O’Neill milk 200 cows on 106ha at Artigarvan, Co Tyrone.
The herd is predominantly made up of Holstein and Montbeliarde crosses in an autumn-calving system.
Annual yield averaged 9,300litres/cow last year with 2.45t of concentrate fed per animal. This gives 3,800 litres of milk produced from forage, more than twice the NI average.
Crossbreeding has helped increase milk solids, which exceed 700kg/cow. Butterfat averages 4.44%, with protein at 3.35%.
Cows are currently averaging 29 litres/day after 215 days in milk, with cows fed to yield and currently receiving an average of 5.5kg of concentrate.
“Good-quality forage is at the heart of the cow’s diet and the heart of profitable milk production,” said Albert.
Swards are routinely pre-mowed 12 hours before grazing to increase dry matter intakes and control grass quality.
This includes in the first rotation, which Albert maintains helps to control the likes of chickweed, without the need for herbicides.
Swards will also be pre-mown in wet conditions where possible. Any surplus or strong grass is baled.
Grass yields and fertiliser
Grass growth is measured weekly, with the farm participating in the GrassCheck programme and typically growing 14 to 15t dry matter per hectare (DM/ha).
The grazing block is heavily stocked at 5.8 to 6 cows/ha.
“We can maintain this stocking rate with regular fertiliser applications. We effectively run two grazing blocks with day and night paddocks.
“Nitrogen is applied within 48 hours of paddocks being grazed, with two paddocks on each block dressed on each application,” said Albert.
To help maintain clover in grazing, Albert has modified his slurry tanker, with a hopper fitted
Clover is included in grazing swards, but not silage swards as the inclusion of clover makes the crop more difficult to wilt down to 25% dry matter in 24 hours.
To help maintain clover in grazing, Albert has modified his slurry tanker, with a hopper fitted that allows him to add in 3-4kg of clover seed when filling slurry.
Silage is a four-cut system, with swards reseeded after five years using late-heading diploid and tetraploid varieties.
Grass seed is sown at 18kg/acre as the brothers have found the higher seed rate gives a thicker sward bottom, with fewer weeds coming through.
Silage ground gets 2,500 gallons/acre and one week later 24-0-13. Fertiliser with phosphorus has not been used on silage ground for 10 years.
First cut is normally harvested in early May. The target is a 30% dry matter forage at 12 ME and 15% protein.
Dry cow silage is made in big bales. No slurry or potash is applied to dry cow silage and this has helped to virtually eliminate milk fever on the farm.
During the winter milking cows get two-thirds grass silage and one-third homegrown wholecrop spring barley.
The main benefit is that the cows are unable to sort the ration
Albert has moved to compact feeding, where the concentrate is put through a grinder before delivery. In the diet feeder, water is added to the concentrate, and forage then mixed in.
“The main benefit is that the cows are unable to sort the ration. We have much less acidosis, improved yields and a big improvement in milk solids,” said Albert.
Cows are fed 5% to 10% above predicted intakes with any rejected feed removed. As this feed is still palatable, it is mixed in with a diet fed to heifers or dry cows.
Offering the additional feed to milking cows has increased yield by an average of 0.75 litres/day.
Cows are bred to sexed semen, with an Angus bull used on cows with any issues or poor teat placement.
Replacement rate has typically been 18%, but has recently risen to 20%, which Albert believes is due to a mineral deficiency, and which he hopes to have now rectified.
The second virtual tour was of the 230ha grassland farm managed by Alastair Cochrane and his sons Conor and Alexander, near Portrush, Co Antrim.
The herd currently has 390 cows in-milk kept in three groups – full-time grazing; partial TMR and zero grazing; and a full-time TMR group.
Cows are yielding 9,000 litres from 2.7t of concentrate at 4.3% butterfat and 3.45% protein. Milk from forage is 3,000 litres.
Cows are crossbred using Holstein and Montbeliarde genetics, with an Angus bull sweeping up.
The herd is predominantly autumn-calving, with 300 cows calving between September and Christmas.
The grazing group were turned out to grass on a 90 acre grazing block on 1 April. By 24 April, cows were at grass full-time.
“We are grass farmers at heart. We try to make the best use of grass as we practically can, to keep as much of the milk cheque as we can for the business,” said Alastair.
When reseeding, diploid grasses are favoured over tetraploids because they produce a denser sward.
Silage is a three-cut system. First cut is normally harvested in early May.
Slurry is applied with a dribble bar. Nitrogen (N) is spread in a split application to improve utilisation with 30 units/acre, followed by 45 units a week later.
Dry cows are fed baled silage made without potash or slurry
Second cut gets 65 units/acre of chemical N and 2,000 gallons/acre of slurry. Third cut gets 50–60 units/acre of N but zero slurry is applied. Wholecrop oats are grown, ahead of a grass reseed.
The TMR consists of 10kg/day of wholecrop, 35kg of silage and 6kg of blend to yield 26 litres/day. Dry cows are fed baled silage made without potash or slurry.
Calving interval is 382 days which is well ahead of the NI average.
The herd was decimated with Neospora in 2006 with 90 cows aborting in three weeks, and 130 animals either lost or culled. Calving interval slipped out to 470 days, with cow numbers falling as low as 180.
Despite the huge challenge, Alastair weathered the storm and has gradually built the herd back up using homebred animals.