Watch: boosting cattle performance with high-quality swards

Grazing management is a huge challenge at this point in the season. Generally speaking, grazing swards will have produced around 70% of the annual growth by early to mid June.

Once the sward has produced seed heads, growth rates will stall for a three- to four-week period before kicking off again in mid- to late summer.

However, this period of low grass growth can be shortened by removing grass that has turned to stem and headed out.

The ideal scenario is to graze out the sward with dry autumn-calving cows or dry ewes, but this is not possible on some farms. The second option is to top the field. A grass mower will do the same job as a purpose-made grass topper.

The idea is to cut the sward down to 3cm to 4cm to leave a fresh sward base to regrow. After topping, apply 25 to 30 units of nitrogen to stimulate grass growth.

Advantages

One of the main advantages of topping grass in June is it will increase sward quality in the next rotation, which usually coincides with the breeding season.

Where suckler cows are grazing high-quality grazing swards, their dry matter energy intake is increased, which has a positive effect on both milk production and fertility.

If cows are left to graze off paddocks of long, stemmy headed-out grass in June and July, then milk production and fertility will be negatively affected, as the cow is taking in less energy with every bite.

Where there is a heavy cover of grass to be topped, you can let cattle back into the paddock for a brief 12- to 24-hour period to clean up grass that has been mowed. They will reduce the amount of dead grass left to decay on top of the sward.

Week in review

Tightening calving spread is top priority

Breeding is under way on our farm, with the stock bulls going out to cows on Saturday 13 May.

Cows are running in two groups, each with a Limousin stock bull. The first group consists of 30 cows with March-born calves at foot. At least half of these animals have now been covered by the bull. The second group consists of 15 cows, which are mainly April-calving animals, and 11 heifers. This group will be increased to 25 cows and 18 heifers over the coming weeks.

The 11 heifers were synchronised using CIDRs and inseminated on Monday 15 May. They will be watched closely over the weekend for any signs of repeat breeding activity.

CIDRs were inserted on Friday 5 May and removed one week later on 12 May, followed by fixed time AI on the Monday.

I did this last year and it worked out well, with 70% conception to AI.

I have another group of 11 maiden heifers and I’m thinking about pulling out another six animals for synchronising and breeding.

Late calving

There are still 10 cows to calve this year, which is far from ideal, but we had a big slip in the calving pattern last year.

Calving in June does not suit my farm system. I finish young bulls at 13 to 14 months of age, so this year’s June-born calves will be too light at housing to take through to finish next June.

Any heifer calves born in this group will not be old enough to keep for replacements next year, as they will be less than 12 months old when breeding starts. At the minute, I am weighing up my options for late-calving cows. I have set a target of calving 60 cows next March and April. This spring, we calved 50 cows during the same two months.

Options

It will be a challenge to pull these cows forward. The only positive is that there are four cows in this group that I am planning to cull. They will be fattened once they have been weaned in autumn, leaving six for breeding.

Late-calving cows will be put on to top-quality grass and run with the bull until early August. They will be scanned around 30 days after the bull is removed. If they are empty, they will be fattened.

My cows are mostly purebred Limousin. When properly fattened, they can hit 350kg to 400kg carcase weight, which gives them a good cull value.

To replace them, I could bring in a few extra in-calf heifers from a herd with a known high-health status that are due to calve in early March. I will make the final decision at scanning time.

First-cut silage complete

Silage was mowed on Tuesday and harvested on Wednesday of this week. I had hoped to get silage harvested last weekend, but the forecast predicted heavy rain for Saturday so I held off.

In hindsight, I should have gone ahead with silage, as we received little to no rain. There is around 55 acres of silage cut, which includes two grazing paddocks with heavy covers.

We did cut five acres of grazing last week and made 13 bales. This has brought our grazing rotation back down to around eight days, which is a bit tighter than recommended.

High utilisation

However, cows are moving around the grazing block comfortably and grass utilisation is high.

I spread 25:5:5 on grazing ground that was cut for silage and on grazed paddocks, so there should be a boost in grass growth over the next fortnight, increasing grazing days ahead.

Around 25 acres of silage ground is being closed up straight away for second cut, so there will also be some silage aftermath available for grazing.

High-quality grass like silage aftermath will help to boost energy intake in later-calving cows, bringing them back into heat quickly.

Silage cost

First-cut silage is yielding around 9t/acre of grass on a freshweight basis. We sprayed Forefront to kill docks and it checked grass growth slightly.

Silage ground got three bags/acre of 24:6:12 (£285/t) and the cost of making silage is usually around £50 to £55 per acre, depending on fuel costs.

Adding in £5/acre for spreading fertiliser and £10/acre for weed control, total costs would be around £117/acre. At 9t/acre, this would make first-cut silage cost around £13/t.

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All reports from the BETTER farm NI programme