Since joining the Northern Ireland Sheep Programme in 2019, Roy and Marilyn Mayers have made sweeping changes to the management of their lowland flock.

During a programme webinar last Thursday, Roy and Marilyn outlined how they set about making changes to their business and the lessons they have learned.

Central to making the changes work has been their willingness to measure all aspects of flock performance and act on this information.

Lambs are weighed regularly using EID software. This data reflects the milking abilities of ewes and is factored into the selection of replacements. Soils are tested regularly and grass growth is measured weekly.

Recording data can be time-consuming. Thankfully, Roy and Marilyn are well supported by their three children, Gavin, Ashley and Tanya, who all play an active role in the running of the farm.

Farm background

The Mayers’ farm extends to a 47ha grassland unit near Tempo, Co Fermanagh. While the land is in a lowland area, soils are extremely heavy and classed as SDA, with a high percentage of peat.

The flock currently consists of 200 March-lambing ewes, an increase from 160 ewes in 2019. Ewes are mainly Texel and Suffolk breeding. There were also 70 replacement hoggets lambing this spring.


In 2020, weaning percentage was 189%, with 56% of lambs sold direct for slaughter and 15% retained for breeding. The remainder were sold as stores.

“We have been trying to increase weaning percentage for a number of years.

“The introduction of Belclare breeding into the flock through rams and bought-in replacements has been a move in the right direction.

“Weaning percentage is now at a level we are happy with, so the challenge will be to maintain it around 190%,” said Marilyn.

Gross margin increased from £522/ha in 2019 to £565/ha last year (€606 to €656).

While this is a moderate increase, the land area farmed during 2020 increased by 20ha to 47ha and dilutes gross margin on a per hectare basis.

Making paddock grazing work in a sheep system

With the realisation that grassland could be pushed harder, Roy and Marilyn were keen to try out rotational grazing and introduced paddocks on-farm in 2019.

“We decided to start small with three fields, around five to six acres in size, and one group of ewes. Being new to electric fencing, we didn’t know if it would keep sheep fenced in,” said Roy.

Each field was split into three divisions using plastic posts. In 2019 and 2020, fences were set up using four strands of wire and a battery fencer. This year, fencing uses three strands of wire.

Water was supplied using an IBC with a self-filling trough attached, which could be moved from field to field.

Paddocks were introduced on the farm in 2019, starting with three fields and one grazing group of ewes. Since then, the full 47ha farm has put into paddocks. \ Houston Green

It was a low-cost setup and ewes were moved to fresh grass every third day.

“We ran around 70 ewes and lambs in the group at the start. Sheep were quick to learn that they were moving to fresh grass when we appeared in a paddock. It worked really well.

“So last year, we put paddocks across the whole farm using the same setup. Our typical paddock is now around 3ac in size and carrying 80 ewes plus lambs, with sheep moved every third day.

“When it comes to moving ewes to fresh grass, it’s simple enough. The ewes know what is happening and will happily move on their own.

“There is usually two of us and we simply lift the wire up and let the sheep under. It takes no more than 30 seconds to shift a group,” added Roy.

Temporary fencing

According to Marilyn, plastic posts are normally placed at 10m spacing on flatter fields. This keeps the wire from sagging and helps keep greater tension in the fence.

If fields are on a slope, posts are placed at shorter intervals to prevent gaps appearing along the bottom strand of wire.

An energiser is used to make sure that electric fences are working properly when sheep enter a new paddock.

The bottom strand of wire needs to be low enough to prevent lambs from slipping under. The middle and top strands need to be at a suitable height to hold back lambs and mature ewes.

Marilyn said: “We are still using battery fencers and they work well. But it is important to regularly check both ends of the wire fence to see if there is adequate current.

“When using older wires, the metal strands can be damaged, which limits current flow. We use an energiser to monitor that fences are working properly throughout the year.”


The only downside that the paddock system presented in the first few years was that the internal divisions meant some paddocks had very little shelter for young lambs in spring.

But problems with pneumonia or hypothermia were avoided by planning out the rotation carefully, especially during poor weather.

Soil and sward management

Grass is measured weekly and the poorer fields are reseeded using this data.

The entire farm is soil sampled and lime is applied regularly, given the higher peat content in soils. The aim is to keep soils around pH 6.2.

New swards are mainly perennial ryegrass, white clover and chicory.

Roy said: “The whole farm gets one bag per acre of urea in spring. After that, we rely more on clover to drive growth in reseeded swards.

“If clover is struggling to support growth, we will dress paddocks after every second grazing with nitrogen. We spread nitrogen on two paddocks at a time, rather than blanket spread.”


Improved grazing management is starting to pay off. Ewes are no longer fed purchased concentrate when turned out to grass after lambing. Creep-feeding lambs is also becoming a thing of the past.

“Last year, our feed bill was down £21/ewe (€24). Multiplied across 270 breeding sheep, it’s a huge saving.

“We are also seeing our percentage of lambs sold fat starting to rise and our aim is to kill all lambs off grass and stop selling stores,” said Roy.

Using performance records to select replacements

The whole flock is monitored using EID and a software package, providing sound physical data to make breeding decisions.

Lambs are now weighed at eight, 12 and 16 weeks of age. These weights are captured on a handheld reader and used to select flock replacements.

“Lamb performance up to 12 weeks is mostly a reflection of how much milk a ewe produces. By weighing lambs, it is easy to pick out replacements from the more maternal ewes.

“The last weighing gives a strong reflection on the performance of flock sires,” said Roy.

Lambs are tagged and recorded on the EID system from birth. To avoid the risk of infection when tagging lambs at such as early age, ear tags are dipped in iodine first.

Weight gain

Last year, ewe lambs gaining more than 250g/day from birth to weaning were kept as replacements.

As 2020 was the first year to use this selection method, the 250g/day threshold was used to avoid culling out too many lambs, but these fears were quickly alleviated.

This year, the weight limit will be set at 300g/day to speed up the rate of genetic progress in the flock, as the higher weight gain limit means greater selection pressure.

Only the female lambs from the best twin-bearing, maternally bred ewes will re-enter the flock for breeding.

Flock health planning pays off

At the outset of the programme, all of the participating farmers completed a flock health plan. It was an exercise that Roy and Marilyn were keen to complete.

Prior to the programme, there was always a small cohort of ewes that were scanned in lamb every spring, yet would turn out empty when lambing finished.

The flock has increased to 270 breeding sheep, with all aspects of flock management recorded. \ Houston Green

“We decided to blood-sample these ewes last year. It turns out there was a low-lying presence of toxoplasmosis and enzootic disease in the flock,” according to Marilyn.

“We never considered this to be an issue, as the vast majority of ewes lambed as normal. It was just a handful of ewes that seemed to lose lambs and we generally accepted this as being normal.

“Last August, we vaccinated ewes as a preventative measure and will continue to do so in future.”

Health planning and blood sampling also proved advantageous last summer when it came to lamb performance. Again, the flock always seems to hit a period of low weight gain in early summer, which would be put down to weaning of lambs.

But because of the regular weighing, alarm bells started to ring when the weighbridge showed a major downturn in daily liveweight gain during July.

Blood sampling confirmed a cobalt deficiency, which was addressed by regular oral drenching. This year, lambs will be given a mineral bolus in advance of the problem developing.

This should avoid any drop in weight gain during the summer, meaning more lambs will reach finishing weight earlier than previous years.

Ewes hit peak milk production around six to eight weeks post-lambing

The webinar also included a presentation from CAFRE sheep technologist Dr Eileen McCloskey, who outlined the role of grassland management at the college’s lowland sheep unit.

The farm grazes 200 ewes, plus lambs, on a 12ha block split into seven paddocks. Silage ground is excluded from this area, although surplus grass is baled and fed back to ewes during winter.

According to McCloskey, the grazing period from May to late July is crucial for maintaining high levels of weight gain in lambs.

“Ewes hit peak milk production around six to eight weeks post-lambing and lambs will hit 50% of lifetime milk consumption by six weeks of age.

“After this point, lambs become more dependent on grazed grass to drive weight gain.

“So, managing swards is important to provide short, leafy, digestible swards that lambs can utilise and convert.”

Sward heights

While grass is the cheapest feed to grow, it is still produced at a cost to the farmer. Good management will cut down wasted grass.

Ewes should enter swards around 8cm to 10cm in height during spring and early summer, then be removed when swards are grazed to around 4cm.

Post-weaning, lambs should enter swards at 8cm and be removed around 6cm. Grazing below this residual height means lambs will eat more stem (fibre) than digestible leaf, hitting weight gain.

Dry ewes should be used to clean out swards from 6cm to 4cm.


According to McCloskey, if lamb performance is below target, the main area of concern should be nutrition, followed by animal health.

Farmers should be alert for worm burdens from now on

If grass management is good, then parasite burdens are more likely to be problem. Farmers should be alert for worm burdens from now on.

Rather than routine worming, taking dung samples before and after dosing will determine if a drench is required and whether or not it was effective.

“Heavy worm burdens will be harder to treat in one dose, which is why dung sampling is a good idea, to determine if a follow-up drench is required.

“If lifetime weight gain drops 20g/day because of a heavy worm problem, it will take an extra week to get lambs to slaughter weight.

“If lifetime weight gain drops 50g/day, slaughter date is delayed by as much as four weeks, so it pays to have an effective treatment plan in place for parasites.”