The 2021 grass growth season has been hugely variable for many farmers.

There have been periods of lower than normal grass growth, followed by short bursts in growth and drought-like conditions for some to add into the mix.

Current grass growth supplies continue to vary across farms depending on location, stocking rate and the potential growth response in swards.

Drafting variability

There is also variability at farm level in drafting progress.

Some farmers who took advantage of the higher prices and kept lambs moving at lighter weights or supplemented lambs targeting getting a higher percentage away at higher prices are typically on track or ahead.

Others limited by poor grass growth rates are running behind.

Attention in early and mid-season lambing flocks should be now turning to ensuring there is a sufficient supply of grass to prepare ewes for breeding.

Teagasc targets

Teagasc targets for a mid-season flock lambing from the start to mid-March are to have at least 45% of lambs drafted for sale by mid-August, rising to 70% by mid-September.

Ewe lambs selected to be retained for breeding should be included in these figures. It is also worthwhile assessing lambs remaining on farm to explore your options.

Finishing or marketing plans will vary depending on the weight of lambs. As such lambs should be weighed and this information used to formulate the most suitable options for your flock.

Where lambs are on target and performing satisfactorily on a high-quality grass diet, then there may not need to be any changes made.

If lambs are falling well behind target and it is likely to result in them competing with ewes for grass supplies at mating, then action needs to be taken.

If grass supplies are positive and you are starting to supplement to underpin performance in the weeks ahead, then feeding 0.3kg to 0.5kg, with access to good-quality grass, will generally more than suffice.

However, this depends on grass quality and the type of lambs being fed. For example, it may be beneficial to offer higher supplementation to ram lambs with a good frame that are short on flesh for faster finishing.

Group similar lots

It is advisable to go through lambs and group into similar lots, with a better response to be gained from supplementing lambs that are closer to finishing.

When grass supplies are tight, do the sums and decide if supplementing or selling into a lively store lamb market is the best option.

There is little point in slaughtering light, poorly finished lambs with kill-out, carcase grade and price all taking a major hit

Reports continue of lambs being killed underweight and underfleshed.

There is little point in slaughtering light, poorly finished lambs with kill-out, carcase grade and price all taking a major hit.

This is the case in a normal year and should gain even more credence in 2021 with the strength of the store lamb market and prices on offer.

Finishing options for hill lambs

For many hill flocks operating on tougher terrain, weaning is likely to have only taken place recently or is imminent. Establishing a finishing or marketing plan for lambs should be high priority if this task has not already been completed.

Similarly to lowland flocks, the main concern on hill flocks should be to ensure sufficient grass is available for the ewe flock, with any surplus grass utilised in an optimum manner for adding value to lambs. The starting point in this practice is weighing lambs and grouping them by weight. This will also help to assess flock performance.

Grouping lambs into four weight categories – less than 25kg, 25kg to 30kg, 30kg to 35kg and greater than 35kg – will be sufficient for most flocks.

For flocks on farms with a high percentage of improved or green grazing and possibly utilising crossbreeding in a percentage of the flock the target should be to have in excess of 80% of lambs weighing in excess of 25kg.

On harder hills where ewes with a lower mature weight are running there could be in the region of 30% to 40% of lambs weighing less than 25kg.

Options available

The weight category in to which lambs fall will influence the options available;

Less than 25kg: These lambs are typically a longer-term prospect and a question which needs to be asked is what growth potential is present. Ideally these lambs need to be grazed on until late in the year or early 2022 and allowed to develop a frame before finishing. The caveat to this is where lambs do not have potential to reach French weights and a light lamb market outlet is available for carcases between 12kg and 16kg.

25kg to 30kg: These lambs are a similar prospect to that described above. There is likely to be more scope with these lambs to bring them to heavier carcase weights but the economics of this route are also based on allowing lambs to develop a frame before transferring on to an intensive finishing diet. Transferring lambs on to an intensive finishing diet before they have been allowed to develop a frame will only result in lambs finishing at a light carcase weight or risk going overfat.

30kg to 35kg: These lambs could be transferred on to a finishing diet but a shorter period at grass would pay dividends in lowering finishing costs. It is also a good option to introduce supplementation at grass where the ultimate plan is to finish lambs indoors.

35kg upwards: This group of lambs possibly have the best array of options available to them. Where good-quality grass is available they can be retained on grass in a bid to achieve cheap weight gain while the feasibility of supplementing heavier lambs to bring to a level of finish suitable for slaughter is improved with a shorter finishing period. These lambs are also a good option to sell live as the heavier liveweight will improve returns.

To sell live or finish?

The strength of the live trade for store lambs is providing a real option for farmers to build this outlet into their plan for marketing/finishing lambs. Farmers should weigh up the live trade and use typical values for the type of lambs on farm to feed in to finishing budgets. The Teagasc store lamb calculator which can be found at will provide a good blueprint.