CAFRE dairy herd preparing for turnout to grazing

Date published: 3 March 2025

Implementing and demonstrating this ethos in the CAFRE dairy herd is of key importance as it has several benefits, both economically and environmentally. Grazed grass is the cheapest feed resource available for dairy cows and will have a big impact on the amount of milk produced from forage.

Robert explains: “The herd of Holstein dairy cows at the CAFRE Dairy Centre are managed in an autumn block calving system, with 174 cows calved between mid-September and Christmas Day in 2024. The cows are housed three weeks pre-calving and remain housed once calved. Post calving, excellent quality forage is targeted to the milking cows, including 1st and 2nd cut grass silage along with maize silage, to maximise milk production from forage through optimising dry matter intakes (DMI) and to ensure cows are on a rising plane of nutrition towards peak milk yield and breeding.”

Whilst there are several benefits to an early turnout to grass, there are certain risk factors to be considered when turning out autumn calved dairy cows to grass, including acidosis and reducing fertility performance. At CAFRE turning dairy cows out to graze happens on a gradual phase, based on several criteria.

Breeding for the CAFRE dairy herd commences annually on 15December, after four weeks of breeding, eligible cows are scanned on a weekly basis. Once three weeks of scanning has been completed, thoughts turn to creating a separate group of cows which are ready to graze. The criteria for cows to enter this group include being a minimum of 50 days in-calf, cows which are below a daily milk yield of 30 litres and heifers which are below 28 litres.

Once a separate physical group is created, their diet is transitioned, essentially decreasing the amount of milk provided through the TMR diet and initially putting a proportion back in through the parlour, before decreasing it gradually over several days. Transitioning more of the concentrate feed from the TMR to in-parlour feeding also allows for quicker adjustments to be made if required due to grazing conditions.

Robert continues: “Grass measuring on the CAFRE dairy herd grazing platform commenced on 7February, with an average farm cover (AFC) of 2,136kg DM/ha, with a good grass wedge already in place due to the previous autumn grazing management.”

Once a few days of settled weather are forecast and ground conditions allow, the grazing group of cows will be turned out to graze gradually. This will mean cows going out to graze for 3 to 4 hours after morning milking for 4 to 5 days before staying out at grass between morning and evening milking, being allocated 10kg DM of grass per cow per day. This gradual transition helps to minimise any nutritional upsets and sudden reductions in milk yield.

On a typical year this group of cows will graze by day until going to grass full time in late March. Around this time the remainder of the herd will commence grazing and join the grazing cows by day, in one grazing group, before being drafted back into the shed for the night, after the evening milking. The number of cows housed at night receiving a TMR ration will decrease weekly as cows continue to meet the grazing criteria until mid-late May.

The dairy cows will initially be turned out on medium pre-grazing covers (2,400 to 2,600kg DM/ha) to acclimatise them to back grazing. Once cows are achieving the target grazing residuals, they will be moved onto paddocks with higher grass covers (2,700 – 2,900 kg DM/ha). Grass quality throughout the 2025 season will be largely determined by the grazing management over the first and second grazing rotations in the incoming weeks.

Incidents of poaching will happen occasionally when trying to get cows out to graze. With good grazing infrastructure including lanes, multiple access points, water trough availability and a flexible attitude, these incidents can be minimised. It is unlikely that lasting damage will be caused from an isolated incident of poaching, however care should be taken to avoid these areas being poached in subsequent grazing rotations.

The second grazing rotation will begin at CAFRE when grass covers of 2,700 – 2,800 kg DM/ha have re-grown on a minimum of three paddocks. Depending on ground conditions following the first grazing, cows will be moved onto to the second rotation earlier on dry days, saving the remaining first rotation paddocks for wet days.

Summary

As we look towards spring, put plans in place to make the changes necessary to prepare cows for the transition to grass and assess what grass covers you have available. An early and gradual transition to grazing will decrease feed costs, create a good grass wedge, improve grass growth and grass quality going ahead into the new season. Discuss the most appropriate option for your farm with your local CAFRE Dairying Adviser.