The need to lift overall output is a common theme across both sheep and beef enterprises in the project. When we talk about output, we are talking about the total number of kilos of lamb/beef produced each year.

While we measure output, and indeed gross margin on a per head basis (output/ewe or GM/ewe), as it is the easiest measure to compare, we really should be looking at output or GM on a per hectare basis as well. That way we can compare different enterprises across the farm. If we decide in the morning to take the area the sheep usually utilise and grow spring barley this year instead, what will be the difference in output and gross margin per hectare across the two systems?

People may say that it is one and the same thing, and to a large extent this is true. However, at higher stocking rates there is a tipping point whereby increasing the stocking rate further will reduce output/head yet may still increase output/hectare. The main point is that to run a successful business farmers need to have a handle on their figures.

Scanning rate

One of the first figures you hear people quote when you ask about their sheep enterprise is their scanning percentage. While this is a vital and extremely useful piece of information that aids in the management during the last few weeks of pregnancy, it tells me nothing about the overall performance of the flock.

Having a scanning rate in the high 190s or low 200s is often seen as the measure of a successful enterprise. Unfortunately this is not true. Knowing your scanning rate is like buying a lottery ticket, yes you are in with a chance of winning big, but your numbers haven’t been called just yet.

I would much rather hear farmers quote their weaning percentage, weaning weight and percentage of lambs finished off pasture alone. These figures are true measures of the overall performance of a sheep enterprise.

There is little point in scanning at over 200%, feeding to this scanning rate pre-lambing and only realising 130% of the lambs at the other end of the production system. You are feeding lambs that you will never sell. While there will always be losses between scanning and weaning, these can be minimised through improved management. While scanning at 200% is brilliant if you can wean 185-190%, the truth is that currently most farmers would be much better off scanning at 170% and weaning 160%.

Weaning percentage

Weaning percentage is the number of lambs weaned per ewe that went to the tup. This figure can be made look quite good by calculating it across in-lamb ewes alone. For an accurate measure, however, the total number of females exposed to the tup must be included.

As discussed in a previous article, weaning should be taking place when lambs are 12 to 14 weeks old. At this stage less than 20% of the lamb’s daily intake is from the ewe’s milk, with the other 80% coming from pasture.

Therefore, the lamb is in direct competition with the ewe for the best available grazing at this point. By weaning the lambs and allowing them access to the best grazing, daily liveweight gain will increase.

The ewe’s daily grass requirements will decrease by 20% as she is no longer lactating and can be used to mop up poorer-quality forage after priority stock have finished.

Every 0.1 increase in lambs weaned/ewe is worth over £7/ewe. By concentrating on weaning percentage rather than scanning percentage, we can make a significant impact on gross margin per ewe. Therefore, moving from the national average figure of 1.3 lambs/ewe to an achievable 1.6 lambs/ewe will result in an increase in output of £21/ewe – across the whole flock this soon becomes a substantial figure.

Improving the numbers

So how do we make these 0.1 lambs/ewe increases? First of all we need to find out where the losses are occurring. Are there too many barren ewes at scanning time? Are there issues with ewe body condition at the time of going to the tup? Ewes that are too thin or too fat going to the tup will have a reduced litter size. Having body condition correct at critical times in the year can make the whole production system run much more smoothly.

If scanning is satisfactory, are there a large number of losses between scanning and lambing time? Are you vaccinating for clostridial diseases, toxoplasmosis or enzootic abortion? Again, how was ewe body condition managed between scanning and lambing and was nutrition correct pre-lambing? Remember, 70% of lamb birth weight occurs in the last seven weeks of gestation. Is fluke a problem in ewes?

Lambing diary

While keeping a detailed lambing diary may be a bit of an extra effort during what is an already busy period, once the dust settles on the lambing season this information is vital to make improvements in years to come.

Our focus group provides farmers with a lambing diary that can be printed out and brought to the lambing shed. This is a simple sheet that records the number of ewes that lambed on a certain day, whether they were singles, twins or triplets, the number of lamb deaths per <24 and >24 hours and a comments section to write in cause of death (where known).

Going through the lambing diary with the farmers post-lambing, it’s amazing the lessons that can be learned. We will all remember a few cases of lambs being lost for whatever reason, but there is no way we can remember each death and adding up the losses attributed to each cause of death will likely flag a problem that you didn’t know you had.

All this information is useless unless you use it to put a plan in place for the following year. Sitting down with your vet and discussing the findings is always a good place to start and can help form the basis of a flock health plan.

Weaning weight

For the focus farms we have set a target weaning weight at 12 weeks of 30kg (21kg for hill flocks). To achieve 30kg at 84 days old, twin lambs need to be gaining just over 290g/day.

This is an achievable figure provided the ewe has plenty of milk in early lactation, ie pre-lambing nutrition was correct and she is getting to good grass post-lambing.

Using rotational or paddock grazing will ensure ewes and lambs have constant access to grass of the highest quality that will drive milk yield in the ewe and, therefore, daily live-weight gain in the lambs.

At around 8p/kgDM, grazed grass is the cheapest feed we can supply to our stock. Compare this with grass silage at 12-14p/kgDM and concentrate feed at anywhere from 22p/kgDM+, it is easy to see why grazed grass needs to make up the majority of the diet. People may think that grass needs to be supplemented, however in early spring, and right through the summer months, grazed grass is more than adequate to meet both energy and protein requirements of all classes of livestock.

The more lambs you can get out of the system from grazed grass alone, the higher your gross margin will be. What proportion of your lamb crop are you currently getting finished from grazed grass alone? Do you have a large carryover of lambs at the turn of the year? What can be done to get more lambs out of the system earlier?

While this spring farmers are seeing excellent prices for lambs, how many years in the last 10 have such prices been achieved? Also, how much extra DM of feed has a lamb slaughtered in February consumed compared with one-off grass in August?

In all likelihood, the prices being achieved this spring are very much needed to cover the feed additional costs.

On some of the focus farms there was a large number of lambs still on-farm at the turn of the year. The problem with this is that, while they were been supplemented with feed, they were also moving around the farm in the winter months, eating up every bit of grass available.

A knock-on effect of this was that it left a shortage of grass for ewes both pre-tupping, through the winter and in early spring post-lambing. This led to ewes being in poorer condition at lambing time than desired, which meant lower milk production in the ewes in the subsequent year and, therefore, there were going to be even more lambs on-farm the following winter.

To get out of this cycle, some of the farms decided to sell whatever was left on farm come mid-November store. Others put lambs on neeps to get them off grass fields and increased concentrate feeding.

This decision will pay off in the long-term, with ewes getting more priority through the winter months – managing body condition more closely and improving grassland management throughout the grazing season.