Targeted use of dairy sexed semen and Aberdeen-Angus sires is helping one spring block-calving herd make the most of everything produced on farm.
Concerns over low conception rates usually put spring block-calving herds off from using sexed semen, but Shropshire dairy farmer Tim Downes has proved performance needs not suffer.
Fertility is the linchpin to the system at The Farm, Shrewsbury, where Tim and wife Louise run 480 organic cows across two units.
With cows calving in a 12-week block from February 15, the business can ill-afford for cows to slip out of the calving pattern; hence why they have previously only dabbled in using sexed semen on heifers.
However, their breeding strategy underwent a marked shift this season, following farm results from Cogent showing their SexedULTRA 4M product could achieve conception rates similar to conventional semen, due to double the amount of cells per straw.
As a result, this is the first year Mr Downes has had the confidence to used sexed across cows and heifers.
Having taken the leap, ‘the proof has been in the pudding’, with cows achieving 60% conception to sexed semen and heifers nearly 70%.
Results are similar to previous years on 34conventional semen. However, performance took a hit because of the hot summer, so rates are likely to be even better next year.
Mr Downes says: “In previous years, we have not embraced sexed semen wholly, as grazing discussion groups have been sceptical of conception rates, but I think it is coming now.
“As a product, we have put a fair bit of faith in it, and the results have proved fairly well.
“Signs are very positive and I do not think we would move away from it.”
The main reasons for using sexed semen centre around making the most of everything produced on-farm. Sexed semen enables the business to breed its own replacements from the most fertile cows and limit the production of lower value, pure dairy bull calves.
Aberdeen-Angus can then be put on the rest of the herd to produce animals to be sold as 12-week-old calves or finished for Dovecote Park/Waitrose.
The fact calves have to be fed on whole milk as part of their OMSCo milk contract has been another factor in ensuring everything produced has a high value, as Mr Downes explains.
“Our main reason is the economics of feeding milk to Friesian bull calves, which there is a market for, but it is only a select organic market that might not cover the costs of the milk going in.”
"We will go from strength to strength using sexed at the start of the season"
This season, sexed semen was used on cows and heifers for the first three weeks of service, which began on May 15. Cows and heifers are served at the same time to ensure there is plenty of fresh colostrum around at calving.
Mr Downes says: “We put Irish Friesian on everything and used a blanket approach for the first two to three weeks to sexed semen; predominately to allow us to have replacements born at the earliest opportunity so they have a chance to grow to calve at 24 months. And they will be the most fertile animals.”
Most stock will get one chance to sexed. However, a handful of cows that have had health or fertility problems in the past will go straight to beef.
Cows not conceiving to sexed will then be AI’d with Aberdeen-Angus two or three times and a sweeper bull will then assist where needed. Heifers will just have sexed, then a sweeper bull.
The team use a combination of tail paint and a collar-based automated heat detection system on cows.
The automated system helps pick up less obvious heats and will auto-segregate animals due for service at milking, while tail paint and visual observations add an extra layer of accuracy. Scratch cards are used on heifers.
This is just one example of how the business is focused on optimising herd fertility. Routine vet checks pre-service, to ensure cows are cycling and prepared for mating, are also seen as important.
Staff training is held in high regard too, with Shropshire Farm Vets used to train up the team on heat detection. Everyone is also responsible for recording heats, with any problems and three-week service eligibility noted on a fertility spreadsheet in the office.
Fertility is also top of the list as part of bull selection. Bulls are first selected on profitable lifetime index or economic breeding index (used on Irish bulls). Spring calving index is also considered.
The herd is a mix of Norwegian Red, New Zealand Friesian, Dairy Shorthorn and Fleckvieh crossbreds. In order to make the most of SexedULTRA 4M, the Downes have opted for Irish Friesian genetics this year, which includes Kirkby Premier, Kirkby Jupiter, Clondrohid Black Lightning and Jean Jo Absolute. Oakchurch DeAdmiral was then used as the Aberdeen-Angus sire.
Mr Downes says: “We aim to produce a cow that suits an organic system in terms of conversion of forage, ability to walk well and be resistant to disease. Stature is important. We do not want very tall or small cows. They need to eat plenty of forage and walk.”
Moving forward, Mr Downes is committed to using SexedULTRA 4M. Usually, he would expect to get about 50:50 Friesian steers and dairy cross Aberdeen-Angus calves.
However, with more animals in-calf to Aberdeen-Angus this year due to targeted sexed semen use, there should be a greater number of higher value beef calves on the ground next spring.
More ‘normal’ summer temperatures should hopefully also boost conception rates next season.
Mr Downes says: “The likelihood is we will not get the heat again which caused us some issues, so I think we will go from strength to strength using sexed at the start of the season.”