Practical implications of conversion to organics on hill sheep farms

The appropriate system of sheep production on hill farms is farm specific. It depends on factors such as the quality and amount of enclosed green land available along with the harshness of the hill grazing environment on the farm.

Damian Costello, Teagasc Sheep Specialist, and Elaine Leavy, Teagasc Organic Specialist, outlined the factors hill sheep farmers have to consider with organic conversion.

A number of non-organic farms on the Teagasc Sheep BETTER farm programme, where sufficient improved ground is available, are successfully running both a dedicated hill flock alongside a crossbred flock. At an adjusted stocking rate, this system is also feasible for organic farms. The extent and quality of enclosed green ground on the farm will determine if finishing organic lambs to slaughter is economically viable.

Breeding policy

As with all sheep systems, a defined breeding policy puts you firmly in control of the ewe breed that will make up your flock into the future. The target should be to breed replacements from within the flock. However, in an organic system, with a derogation from the OCB, up to 20% ewe replacements (that have not previously lambed) can be bought in from non-organic sources. Rams may also be sourced from nonorganic breeders. As previously mentioned, land type will have a bearing on whether cross breeding a proportion of the ewe flock is an option. Table 1 below outlines how current productivity of a hill flock should be considered when making this decision.

Table 1: Potential breeding strategies for hill flocks at different levels of output

The merits of the various hill breeds and strains are often debated among hill sheep farmers. Studies carried out as part of the Teagasc Sheep BETTER farm programme have found that there were more significant performance differences within the individual breeds and strains than there were among the various breeds and strains of hill sheep. Ultimately, each farm should choose the breed best suited to their hill environment and strive to breed for improved flock performance. As progress is made in performance recording among hill breeders, choosing high genetic merit sires will improve the flock over time. Where crossbreeding to produce lambs for slaughter is part of the farm system, rams that are high genetic merit on the Terminal Index will produce lambs that grow faster and be quicker to get to market.

Grazing management

The aim should be to graze the hill flock on the hill for the maximum time possible each year at a stocking rate that will neither lead to overgrazing nor undergrazing. For organic hill sheep farms, commonage can be grazed by sheep once they are properly hefted. It is important to manage the enclosed green ground or improved grassland for optimum grass production to be used at key times such as mating, either side of lambing or lamb finishing.

Maintain productivity of improved grassland

• Soil analysis and applying lime to optimize pH is the first step, where land type and terrain is suitable and safe to travel with machinery;
• If farmyard manure and/or slurry is available, they should be applied to maintain/build P & K indices as per soil analysis;
• Where the stocking rate and output in terms of number of lambs produced justifies it, reseeding suitable areas including incorporating white and red clover into the sward will fix nitrogen naturally. Studies have shown that with a grass and 20% clover sward, there is potential to fix from 100 to 250 kg of nitrogen (N) from the atmosphere, with the greatest potential where no chemical N was applied to the sward as is the case in an organic system;
• It is critical to have the fencing infrastructure to allow rotational grazing and to correctly manage these swards post establishment;
• The control of problem weed species is restricted to physical and mechanical means such as topping. It is also advisable to avoid poaching and rutting with machinery as this can promote weed seed germination.

Flock nutrition

The main component of the diet in an organic hill sheep system is grazed forage. The aim is to produce the entire forage requirement on farm. On hill farms where silage or hay form part of the late pregnancy feeding regime, the production of high quality silage offers the opportunity to reduce the level of expensive organic concentrates required by ewes pre-lambing.

There are organic concentrates available for supplementary feeding in late pregnancy in the form of premixed nut/ration at a guideline cost in 2023 of €850-950/t. In line with organic standards, lambs must feed on maternal milk for at least the first 45 days of life. If any ewe has excess colostrum, collecting and freezing in suitable quantities (200ml initial feed for 4kg lamb) is advisable. This can be fed to lambs where mothers have inadequate colostrum supply. Surplus lambs should be cross fostered where possible.

Currently there is no organic certified colostrum substitute and lamb milk replacer on the market. Where maternal milk is not available, non-organic milk replacer may be fed to lambs. These lambs must be clearly identified by tagging and must be marketed as non-organic lamb. The system of indoor finishing of lambs requires good husbandry and is challenging for organic lambs given that at least 60% dry matter of the diet must be from roughage. This applies post weaning and does not apply to the diet of lambs up to weaning. Where supplementary concentrates are required to finish lambs, the preferred option is to supplement at grass.

Organic sheep housing

The traditional practice of out-wintering hill sheep suits organic production once it is within cross compliance requirements. There are hill farms that house some or all of their flock for a period of time. When housing sheep organically, there are specific space requirements as outlined in Table 2. At least 50% of the total floor areas must be solid, that is, not of slatted or grid construction and available to stock at all times. Nonorganic straw is permitted to be used for bedding.

Table 2: Organic sheep housing floor area requirements (net area available to each animal)

Flock health plan

When a farmer undergoes conversion to organic status, in consultation with a veterinary surgeon, a flock health plan is prepared. The plan will take farm history into account and will outline how the farmer will tackle health issues in the future while conforming to the organic farming standards. The withdrawal periods for medicines/treatments are longer for organic animals - at least double the withdrawal as indicated by the manufacturer. Some meat processors have markets that require up to three times the standard withdrawal period.

The areas addressed in a typical flock health plan for hill sheep would include the following:

• A closed flock to reduce the risk of introducing disease;
• Control of stomach worms in lambs using techniques such as mixed grazing with bovines and grazing lambs on pastures with lower parasite burden after weaning;
• Measuring faecal egg counts regularly to identify parasite burden and if there is a requirement for treatment;
• Appropriate timing of shearing and removal of soiled wool to lessen the risk of blowfly strike;
• Preventative treatments such as pour-ons for blowfly and other external parasites are allowable, as are dipping products except for those containing organophosphates;
• For lameness, the use of zinc sulphate or copper sulphate in appropriate foot bathing facilities. The use of formalin based footbath solution is prohibited;
• Plan liver fluke control strategy based on farm history. If possible, secure liver reports from factories post slaughter as an indicator of levels of infection. Where practical, avoid grazing high risk areas during the autumn/winter period. Treatment is permitted with veterinary consultation;
• Vaccines are permitted where farm history indicates that they are required.

Marketing organic lamb

It is important to make contact with other organic producers and meat processors about potential markets. Currently in Ireland, there is one main processor of organic lamb. A premium of 15% above the conventional price is usually achievable. On farms where finishing lambs is not possible, they may be sold as stores.

To access the full proceedings from the National Hill Sheep Conference, click here.