Tag: sheep

Using the Calculator: focus on sheep

Posted on July 17, 2023 by - Calculator

This month we’re focusing on calculating emissions and sequestration from your sheep enterprise.

To accurately estimate the emissions and sequestration from your sheep enterprise, you will need to add data to the following sections of the Calculator:

  • When setting up the report, make sure you enter the area of grazing (grassland) as well as any non-agricultural land area and cultivated land (arable or horticultural)
  • Use the Livestock section and select sheep. Add as many entries as you need to cover your flock. So for example, you may have two breeds with different liveweights, in which case enter the ewes from the first breed with one liveweight and then the ewes from the second breed as a separate entry with their own liveweight. This will give you more accurate emissions from their enteric fermentation (gut methane).

  • To calculate the average head of livestock on farm over a 12 month period, take the number in a particular livestock category per month (so you have 12 “snapshots”) add these  together and then divide by 12. Our data collection sheet has a helpsheet for this. For lambs you may want to use the same approach for calculating average liveweight (our defaults assume a midpoint liveweight through the year for growing lambs but growth rates won’t be linear so using the snapshot approach may be more accurate).
  • “Livestock” entries capture the CO2 equivalent of the methane emissions from enteric fermentation and of the nitrous oxide (N2O) emissions from the animals’ manure over the course of the year. The Calculator asks you how this manure is managed as this has an impact on the N2O emissions.
  • You will need to account for any supplemental feeding via the Livestock > Animal feeds option – this is for brought-in feeds that were produced off-farm.
  • If you use any additional fertility sources, you will need to account for these where they have been brought-in. For manures, slurries, AD digestate, water treatment cake, lime or mineral fertilisers, use the Crops tab. For chemical fertilisers, use the Inputs tab.
  • Account for all your fuel use, electricity use, consumables, inventory items and waste produced using the relevant sections (Fuels, Materials,  Inventory, Waste).
  • We recommend getting your soil sampled and have a guide on how to do this effectively and affordably. By monitoring your soil organic matter or soil organic carbon over time you can begin to log sequestration rates in your grazed (or other) soils. Once you have two years’ worth of soil sample results, you can enter these in the Calculator under Sequestration > Soil Organic Matter (you will also need bulk density measurements and a record of the depth of the sample).
  • If you don’t have directly sampled soil data for all your soils, you can use our range of proxy values for different Countryside Stewardship and habitat classes to estimate how much carbon your soils may be sequestering year-on-year. You can also measure the length of any hedgerows and field margins (ungrazed) and enter these to estimate the carbon sequestered in them on a yearly basis.

Getting in touch

If you have any questions/comments please email calculator@farmcarbontoolkit.org.uk

Find out more

You can find all our useful calculator resources here.

This blog was written by Lizzy Parker, our Calculator Manager.

Sheep – how well adapted are your livestock for your management and environment?

Posted on July 15, 2023 by - Insights

Blog written by Rob Purdew and Hannah Jones

In the absence of sophisticated pharmaceuticals and feed blends, local breeds were historically adapted to their local environment. These adaptations included the ability to withstand weather extremes, the local pest or parasite burden, and the ability to finish on local, often low quality, forage. Local breeds, from Herdwick to Norfolk Horns, were selected for generations and identified as the most efficient livestock for their specific set of conditions.

On the cliff tops of Cornwall, highland cattle are the one of the stalwart cattle breeds for scrub management, where season long grazing results in an average 0.5kg growth rate a day. The same animal in a shed with silage and a more tailored ration will continue to grow at 0.5kg per day with much higher associated costs. Unpicking the carbon footprint integrates the sequestration potential of that scrub, soil management, no bought in feed and the added benefit of habitat provision. The animals may finish older, but as I was told once by a farmer “go for optimum not maximum”, in the scrub environment the highlands were profitable.

A recent event at Trefranck farm, showcasing the innovative work between Matt and Pip Smith with the Castle Vets and Moredun research (funded by Innovate UK) has brought another exciting perspective on sustainability, through the breeding of worm tolerance in Romney sheep. With a careful eye on welfare throughout the project, the first insights into breeding for tolerance to worm load has been unpicked.

Tolerance to worm burden is defined as the ability of a lamb to maintain weight gain irrespective of worm burden. Those lambs with the desirable genetics showed the least growth penalty in the presence of an average worm burden. A comparison of finishing time showed that there was a 10 day difference between the least and the most tolerant lambs. When extrapolated across a whole flock this represents a significant reduction in both forage costs and carbon footprint. This research is driven by the need to address the huge problem of anthelmintic resistance found in roundworms in UK sheep populations, and further incorporates guidelines on targeted selective treatment to ensure the selection of resistant worms in pastures is impeded. Good breeding, alongside good management of pasture environment and animal movement will improve welfare and reduce loss of productivity from worm burden.

Reducing overheads, and your carbon footprint can be achieved by doing the basics –  the right breed in the right environment – and doing it really well.