The Teagasc research project 'Growing Resilient Organic Farming Systems (GROFarmS) has trialled finishing hill lambs on organic forage-based diets.

Teagasc research officer, Dr. Frank Campion recently shared some early results from the indoor lamb-finishing study.

As part of the trial, Scottish Blackface male lambs were assigned to one of three treatments over the winter of 2024.

The aim of the trial was to evaluate the impact of different finishing diets on lamb performance, environmental outcomes, and economic viability.

The lambs entering the trial had a starting weight of 29kg.

Split in three equal groups, the lambs were assigned to one of three feed treatments:

Grass silage + 500g/head/day of concentrate;
Red clover silage + 500g/head/day of concentrate;
Wholecrop silage (barley, oats, peas) + 500g/head/day of concentrate.

All silage was fed in bale form, and the concentrate was composed of organic barley, oats, and peas.

For the hill lamb finishing study, lambs were managed under fully organic conditions, with straw lie-back housing.

Throughout the feeding period, lambs were weighed fortnightly and drafted for slaughter at 44kg liveweight with appropriate fat cover.

Commenting on the findings, Dr. Campion said: "Initial findings from the first year of the study suggest that overall performance across all treatments was lower than we would have envisaged.

He highlighted that: “Despite its higher cereal content, selective browsing proved a challenge when feeding the wholecrop silage and its inclusion as a diet did not lead to increases in average daily gain.

“Additionally, due to the wet summer experienced in 2024, we did note some palatability issues with our red-clover silage, highlighting the importance of achieving adequate preservation at ensiling," the researcher added.

Although still early days in the experiment, with repeated trials planned for this coming winter, Dr. Campion noted that initial findings available in the table below point to the need for starting live-weights to be higher for hill-lamb-finishing, as well as that feed intake is emerging as a key driver of performance.

The table below shows the initial findings from the organic hill lamb finishing study:

Commenting on the data above, the researcher said: "Further data collection and repeated studies will aim to identify optimal diet formulations and management practices that support organic hill lamb performance."