Dairy management: Grass, milk recording and maiden heifers

Grazing: Unbelievably good grazing conditions continued this week, but milder and wetter conditions are set to move in from the weekend. For many farmers that have over 70% of the farm grazed, they will be glad to see a bit of softness return as this will boost grass growth. Many farms are on a knife-edge for grass and risk running covers down too low before the second round commences.

Average growth rate for the last week was 16kg DM/day, which is lower than expected and behind the five-year average. The predicted growth for the coming week is in the high 20s, which is about normal for the end of March. Most farmers won’t start the second rotation until there is about 1,200kg on the first few paddocks on the second round. Typically this will happen sometime between 1 and 7 April on “early farms”. Whatever area is left on the first round needs to be rationed out equally between now and then. If the area and the amount of grass in the area isn’t enough for the herd then fill the gap with meal and silage. Reassess the situation every five or six days. The minimum average farm cover you would like to see is 500kg DM/ha by early April.

Milk recording: The number of cows that have been milk recorded so far this year is back about 14% compared to the same period last year. Early milk recording is important to assess how successful the dry period is at clearing up existing infections and preventing new ones. With the widespread use of selective dry cow therapy, this information is important. Waiting until all of the cows are calved will be too late as new infections will have been picked up since calving. I see the two biggest milk recording organisations are now offering Genocells service from 1 April. This is a bulk tank milk test that can tell the SCC of each cow, within a range. To take part, all cows in the herd must be genotyped and ?still need to be milk-recorded.

The milk recording companies say four recordings are required per year to get an accurate Genocell result as the volume of milk produced by each cow is important. One of the biggest drawbacks for me is that the cell count range is set at 0-50k, 51 to 199k and 200 to 249k, and so on meaning it won’t be possible to make decisions on sealer only dry off just by looking at Genocells. Ultimately, it isn’t a replacement for milk recording, rather it provides additional information. It costs €3 per cow per test for 2025 and the expected turnaround time is seven days.

Maiden heifers: In about a month’s time, maiden heifers in the southern counties will start to be served. It’s a timely reminder to get them out to grass, on a settled plain of nutrition and get them thriving before breeding starts. For those planning to use fixed time AI programmes, it might be a good idea to check that heifers are cycling before enrolling them on an expensive programme. Heifers have to be cycling for the fixed time programmes to work. Heifers need to be at 60% of their mature liveweight for breeding at 15 months. For most heifers, this is between 330 and 350kg liveweight.