Top five tips and grazing targets for March

In the Teagasc Dairy Newsletter for March, we read about the top five tips for the month from Joe Patton, Head of Dairy Knowledge Transfer, as well as March grazing targets.

1. Milk recording: record within 60 days of the first cow calving. For example, if the first calving took place on January 25^th, record by March 25^th. This will help to identify and address problem cows early. Check for repeat offenders and assess how effective your dry period treatment programme was.
2. Early turnout: maiden heifers need to be at target weight for breeding (290-330kg for JEX, FR, HOFR) for maximum fertility performance. Early turnout of light heifers to grass along with 2kg of concentrate will deliver a gain of >1kg per day to facilitate hitting target weights.
3. Vaccination: recent advice suggests moving vaccination dates to during the dry period; however, if vaccinations need to be completed for 2023, it is recommended to have them done at least one month ahead of breeding. Remember, maiden heifers need to get two shots, so factor this into your scheduling.
4. Assess body condition: cows that lose >0.5 body condition score (BCS) in early lactation have reduced reproductive performance. Condition score now to identify thin cows that should be put on once-a-day (OAD) milking to improve condition. Late-calving cows (March 25^th onwards) should also be milked OAD if you wish to retain them for the 2024 milking year.
5. Pick your AI bull team for breeding: Teagasc Breeding Week takes place from March 20-24^th and will cover identifying your breeding goals, identifying AI sires and using Sire Advice to allocate sires to help you achieve your goals, along with lots of other information on all things breeding.

March grazing targets

Grazing has gone well during February. Many farmers on dry land will have reached the 25-30% target grazed by March 1^st. The aim is to have about 65% of the farm grazed by St Patrick’s Day, according to the spring rotation planner.

Regrowth levels have to be tracked on the farm from mid-March. The primary time for an increased level of grass growth will be the third and fourth weeks of March. Look at the paddocks grazed early – this will tell you what grass recovery has taken place. There will need to be four to five paddocks with a good level of grass recovery to gain knowledge as to when the second rotation can begin in April.

For those who measure grass, the average farm cover should not drop below 550kg DM/ha at any time during the first rotation, otherwise grass growth will be compromised. Follow grass growth rates on the PastureBase Ireland website: www.pbi.ie.

Ground conditions

As long as ground conditions are adequate underfoot, grazing can take place. When ground conditions are difficult, practices have to be put in place to keep grass in the diet of the cow without causing serious damage to the land. These practices include:

• Grazing for a few hours after each milking;
• Using different entry and exit points to paddocks;
• Grazing low covers of grass in difficult grazing conditions;
• And, using grazing techniques that minimise damage to land.

Fertiliser/slurry

It is important to keep grass growing on the farm. Grass will need to recover after grazing and be ready to graze again in the first half of April; therefore, nitrogen (N) fertiliser and slurry need to be spread. The target is to have about 60 units/acre of N (slurry N and fertiliser N in total) applied to most paddocks by early April. This N target can be achieved through a combination of slurry (about eight units N/1,000 gallons) and fertiliser.

These articles were first published in the Teagasc Dairy Newsletter - March 2023