Organic beef cattle research update

David Flynn David Wall Rioch Fox Peter Doyle Marie McFadden Mark McGee Paul Crosson

Introduction

The Climate Action Plan (2024) has set ambitious targets to increase land farmed according to organic standards from the current area of 225,000 ha (5% of total farmed area) to 450,000 ha (10%) by 2030. The largest organic sector in Ireland is beef cattle production. There are an estimated 40,000 organically-farmed suckler cows in Ireland with 12,500 cattle finished for organic beef production. This indicates substantial ‘leakage’ between organic suckler cow systems and beef output. Given this level of leakage and the recent large influx of farms into organic beef systems (land area farmed organically was 75,000 ha in 2020) it is paramount to develop guidelines for efficient and profitable systems, particularly regarding the finishing phase of the production cycle.

Kildavin farm at Johnstown Castle

Kildavin farm at Teagasc Johnstown Castle in Co. Wexford is being developed as an organic spring-born suckler weanling-to-beef systems research and demonstration farm to assess a range of beef production options and develop clear guidelines for efficient and profitable organic-beef systems. The farm is in its second year of conversion to organic. Kildavin farm is 48 hectares (ha). Soil types across the farm range from reasonably free-draining brown earths to gley and other moderately-to-poorly drained soils. The farm comprises a mix of recently established multi-species swards, older permanent pasture, and two dedicated silage blocks sown with grass-red clover and multi-species swards.

Suckler-bred steers will be reared in an organic weanling-to-beef farming system and finished at three time points:

• end of the second grazing season (approximately 19 months of age)
• end of the second winter (approximately 23 months of age)
• during the third grazing season (approximately 26 months of age)

Production cycle 1

Eighty-two spring-born, early-maturing (Angus crossbred; n=24) and late-maturing (Charolais and Limousin crossbred; n= 58) weanling steers (~eight months old), were sourced and purchased directly from certified organic farms throughout Ireland, in autumn 2024.  On arrival, the weanlings were given access to a straw bed with low stocking density and fresh water and silage. Once settled, animals were vaccinated against respiratory (RSV/PI3 and IBR) and clostridial (blackleg) disease according to the herd health plan. A dung sample for faecal egg count (FEC) was taken, and they were turned out to pasture for about three weeks until housing on 4 November.

For the first winter, they were accommodated indoors on straw-bedded pens and offered either grass red-clover or multi-species silage ad libitum (without concentrate supplementation) until turnout to pasture on 27 March 2025.  During the second grazing season, all animals rotationally grazed both multi-species swards and old permanent pasture, at a target pre-grazing herbage mass of 1500 kg/ha and post-grazing sward height of 5 cm. The multi-species mixture contained perennial ryegrass, timothy, white clover, red clover, chicory and plantain. Samples for FEC were taken every 6-8 weeks during the grazing season to monitor worm burdens.

The 19-month group (n=24) were finished from pasture without supplementation at the end of the second grazing season (7 October 2025), and the 23-month and 26-month groups were accommodated indoors. The 23-month group were offered either grass-red clover silage (n=12) or multi-species silage (n=12) ad libitum supplemented with 3.5 kg fresh weight per head daily of an organic concentrate containing a mixture of barley, oats, beans and peas for a 150-day finishing period (5 March 2026). The 26-month group (n=24) were also offered grass-red clover or multi-species silage ad libitum supplemented with 1 kg fresh weight per head daily of the organic concentrate (‘store’ period) until turnout to pasture on 1 April 2026, for part of a ‘third’ grazing season. They were rotationally grazed on multi-species swards and permanent pasture for a 57-day finishing period, until 27 May 2026. Key measurements include pasture production, nutritive value and agronomy, animal live weight and carcass traits, and economic analysis of the system. Provisional results for the finishing performance of cattle from production cycle 1 are summarised in Table 1.

Table 1. Mean carcass weight, conformation score and fat score for the 19-, 23- and 26-month finishing ages for production cycle 1

Production cycle 2

Seventy-six spring-born, early-maturing (Angus and Hereford crossbred; n=38) and late-maturing (Charolais and Limousin crossbred; n=38) breed weanling steers, were purchased directly from organic farms in autumn 2025. General animal management post-purchase was similar to that outlined for production cycle 1 above.  For the first winter, weanlings were accommodated indoors (3 November 2025) on straw-bedded pens and offered either grass-red clover silage or multi-species silage ad libitum supplemented with 1.5 kg fresh weight per head daily of an organic concentrate (containing barley, peas, oats and beans), until turnout to pasture on 20 March 2026. Provisional results for the weanling growth performance during the 2025/2026 winter are shown in Table 2.

Table 2. Mean growth performance of early-maturing and late-maturing breed weanling steers offered grass-red clover silage or multi-species silage ad libitum supplemented with 1.5 kg of organic concentrates at the start of production cycle 2

Organic beef finishing study

Finishing cattle indoors is the most expensive feeding phase of beef production.  In this regard, there is a need to evaluate alternative organic finishing diets for beef cattle, particularly those incorporating lower-cost, home-grown feeds (both energy and protein sources), to minimise the importation of expensive supplementary concentrates.

Intake, growth, feed efficiency and carcass traits of late-maturing suckler steers offered one of four experimental diets over a 98-day finishing period were examined at Teagasc Grange.  The four diets were:

• Perennial ryegrass silage ad libitum + 3.0 kg barley-based concentrate dry matter (DM) per animal daily – conventional feedstuffs, ‘control’ diet (PRG + Conc.),
• Organic baled grass-red clover silage ad libitum + 3.0 kg organic bi-crop (barley + pea) grain DM per animal daily (RC + Organic Conc.),
• Organic baled grass-red clover silage only ad libitum (RC-only), and
• Organic bi-crop (barley + pea) silage ad libitum (Bi-crop).

Animals were accommodated in pens in a straw-bedded (over a porous membrane) slatted floor shed at a stocking density of 8 m² per animal.

Daily live weight gain and carcass weight was greatest for RC + Organic Conc. and lowest for RC-only, with PRG + Conc. and Bi-crop being intermediate (Table 3). Feed efficiency was best for PRG + Conc. and RC + Organic Conc., and worst for RC-only and Bi-crop. Carcass fat score was greater for RC + Organic Conc. than PRG + Conc. and Bi-crop, with RC-only intermediate. Kill-out proportion or carcass conformation score did not differ between the four diets. Financial margins were highest for RC + Organic Conc. and lowest for Bi-crop. Overall, economics of the finishing system was extremely sensitive to store cattle price and beef carcass price.

Table 3.  Dry matter (DM) intake, growth, feed efficiency and carcass traits of finishing steer offered one of four finishing diets based on perennial ryegrass silage (PRG), grass-red clover silage (RC) or Bi-crop silage.

Compiled and edited by Mark McGee and Paul Crosson, Teagasc, Grange Animal & Grassland Research and Innovation Centre, and first published in BEEF2026 – Driving Sustainable Performance, additional reading from BEEF2026 is available here.