With the busiest few weeks of calving now behind him, Dermot O’Connor can take stock of how the spring has gone so far.

Milking 200 cows near Shanagolden in west Limerick, Dermot is content that actions taken last year have resulted in a smoother spring so far this season.

The big issue last year was milk fever in cows and scour in calves. Both are a scourge.

Thankfully, milk fever is easier sorted.

In Dermot’s case he focused on four areas:

  • Reducing the dry period to a maximum of eight weeks for mature cows in good body condition score at drying off. Heifers get 10 weeks dry.
  • Feeding sweetened cal mag to cows five days before calving.
  • Increasing the feed space allocation per cow during the dry period so cows have more access to silage with minerals sprinkled on it.
  • Using free access mineral licks in sheds for more timid cows.
  • Last year, he had 20 clinical cases of milk fever which is 10% of the herd. It’s said that for every one clinical case there can be up to six sub-clinical cases which are not detected.

    So far this year, there have been two cases of milk fever. Perhaps two is too many but it’s a big improvement on last year.

    One of the knock-on effects of the high levels of milk fever last season is that calving rate is slower this year.

    When the Irish Farmers Journal visited the farm on Monday Dermot had 60% of the herd calved, which is about 10% back on where it should be.

    Dermot uses different colour tape on cows legs to determine how many days they stay out of the tank. This chart goes through what day each colour goes on and off.

    He’s putting this down to a lower than normal conception rate to first service as more cows were suffering from sub-clinical milk fever last season.

    Dermot says he normally hits 85% of the herd calved in six weeks, but that it’ll be closer to 75% this season.

    A bad scour outbreak last season created a huge amount of extra work.

    Only two calves were lost in the rotavirus and cryptosporidium outbreak, but Dermot said it put huge pressure on the farm as sick calves were being fed electrolytes in between milk feeds.

    This year, he vaccinated the cows against rotavirus prior to calving and so far so good.

    He has preventative treatment for cryptosporidium ready to go if he needs it, but is slow to use it until he feels he has to as it could be a bit hard on calves.

    Buckets for baby calves are washed out after every feed.

    All calves get whole milk for the first two weeks before the heifers go to milk replacer. The bull calves get whole milk until they are sold.

    The first bunch of bull calves will be sold this week so that will be a big relief when they go. All calves are fed twice a day and all cows were milked twice a day since the start of calving: “We’ve done once-a-day milking and we’ve done once-a-day calf feeding before and we’d be happy to go back to them if we need to.

    Calves are kept in individual pens for the first couple of days.

    “We’re fortunate to have plenty of good help around this spring so we’re in a position that we don’t need to do once a day,” Dermot says.

    While his father Tom is officially retired, he was whizzing around in the tractor feeding out silage when I was there on Monday.

    Full-time employee Jack Sheahan has been working with the O’Connors since he did his placement on the farm in 2017, while CIT student and fellow Limerick man Padraig Byrnes is doing his 15-week placement on the farm now.

    Grass

    It’s fair to say that Dermot’s main passion is grass and early spring grazing is his all-Ireland final. He had 25% of the farm grazed by Monday, while the target for that day was to have 30%.

    A total of three 24-hour periods of grazing were missed so far this spring, so in reality he has done well to get so much of the farm grazed.

    “I leave the wet spots and will come back to them later. I don’t get hung up about having to finish every field before moving on to the next paddock.

    Good recovery on grazed sections. Dermot drops the wire to create extra gaps into fields.

    “Grazing the front of paddocks is much easier in wet weather so that’s the go-to when weather is challenging.

    “I also have a few paddocks with two or three sides along a roadway so they are great in wet weather and I drop the wire along the road to create extra gaps, where needed, especially if the gap is already mucky from the autumn,” he says.

    When ground is challenging, Dermot will usually split the day’s allocation in half and when they are finished the first half, he will make a call as to whether they need to be housed, or can get the next section.

    Cows have been coming in every night at 10pm and they get a small bit of silage in the shed. As soon as weather settles, they will stay out for the full night – making full use of the dry, free-draining land.

    Average farm cover is 957kg/ha and growth rate is 8kg/day. The grazed paddocks are growing 25% faster than the farm average at 10kg/day.

    The O'Connor herd out grazing earlier this week.

    Seventy per cent of the farm has got either 2,500 gallons/acre of slurry (50%) or 23 units/acre of urea (20%).

    The remaining 30% is the part of the farm that will be grazed first and this will get 2,500 gallons/acre of slurry in the coming days.

    The second nitrogen application will go out in mid-March with everywhere getting 46 units/acre of nitrogen.

    Dermot has identified the paddocks that will be sown with clover this coming year. Combined, they make up about 12% of the farm with half being fully reseeded and the others getting oversown with clover.

    The full reseed will be disced, power harrowed and then sown with a mix of red and white clover and tetraploid and diploid ryegrass.

    While red clover isn’t ideal for grazing, Dermot says he saw it growing well on a visit to Solohead research farm last year and is up for trying it out.

    The plan is to spread little or no nitrogen on these new clover swards after establishment and to graze them at very low covers to give as much light to the clover seedlings as possible.

    Soil fertility in the chosen fields is good at index four for P and K and high pH but Dermot still plans to spread some 0:7:30 later this year to feed the clover plant.

    The fields where clover is being sown tend not to be grazed until last in autumn so there will be a low cow carried into the winter.

    Last year, Dermot spread 216kg N/ha across the milking block and hopes to come under that this year. The farm peaked at 15t/ha of grass growth in 2017 but hasn’t touched that since. This is partly because there is now less nitrogen being spread, but also because 16ha of the milking platform was purchased in 2019 and this had low soil fertility, so this is bringing the average grass growth back to 13.5t/ha.

    Herd EBI

    With 64ha in the milking block the stocking rate this year will be 3.1 cows/ha on the platform. Last year, 216 cows were milked and the stocking rate was 3.3 cows/ha but Dermot culled hard last winter to remove high SCC cows.

    Currently, the SCC is 80,000 while this time last year it was 180,000 so the culling seems to have worked.

    The herd EBI is €173 and the herd is a mix of Jersey crossbred and Holstein Friesian. Average age is 3.5 lactations and 515kg MS/cow was sold last year from a total of 800kg of meal per cow.

    After a busy few weeks, the rate of calving has started to ease and Dermot is getting more sleep. He looks after the nights and is back in the yard for around 9am while Jack and Padraig start milking and feeding calves at 7am. Married to Hazelle, they have three children, Donncha, Elyse and Oisin, so it’s a busy house and a busy yard.