By Jack Bosworth, Director, FJ Bosworth & Sons. Published 26 August 2023.
I hope everyone is well.
Ammonia emissions have become something of a hot topic in the pig industry in recent years, and our family farming business is actively exploring what we can do to reduce any negative contribution we are responsible for.
What is already certain, and what is not
We already know that we will need to cover our slurry stores by 2027 as part of the Government’s Clean Air Strategy, announced back in 2019.
What we do not know is how much ammonia is being emitted, or where in the process the bulk of it is being lost.
DEFRA has gone for the obvious answer: reduce losses from storage. The question I keep coming back to is whether it would not be more beneficial to reduce losses at an earlier stage, namely in the livestock housing itself. Tackling it there would mean:
- Better air quality and health benefits for the animals.
- Reduced odour inside the buildings.
- Losses reduced at the earliest possible point, straight from the pig.
A trial we are looking to run
I have been speaking to a company that produces an in-feed product derived from seaweed, which claims to reduce ammonia in pig slurry by over 50 per cent.
We are looking to complete a trial measuring ammonia levels in our buildings before and after feeding the product. The economics, on paper, look manageable:
| Inclusion rate | Cost per two-tonne mix |
|---|---|
| 0.5 kg per tonne | £9.00 |
| 0.75 kg per tonne | £13.50 |
Those are real, finite costs against an outcome that, if it stacks up, could be material.
What I would actually like to know
Honestly, I would be very interested to see what data is available on the difference in ammonia emitted from an uncovered slurry store versus a covered one.
Of course, different types of cover will have different impacts on losses. Our existing above-ground stores were certainly not designed to support the weight of a cover over the top, so I imagine we would have to fit a floating cover. I am not willing to take my chances on whether the structure is “maybe strong enough” for anything heavier.
The question for policy
If we can demonstrate better control and better reductions of ammonia via an in-feed product than via covering slurry stores, then I have to ask: why is it not listed as an alternative?
Particularly when you are reducing losses at an earlier stage of the cycle.
Perhaps the answer is that an in-feed product is harder to police, while covering stores is an easy-to-follow, easy-to-measure rule. The easy way is not always the best way.
Why this is also a financial question
The best answer is probably to do both: cover the stores and tackle the emissions at source through the diet.
As we all know, though, pig farmers have been through some incredibly tough financial positions since the Clean Air Strategy was announced in 2019. So the honest question is whether that is actually viable when producers are not getting any more for the positive contributions they are already making.
A serious conversation about emissions has to include a serious conversation about how it is paid for. Otherwise we will get the answer that is easiest to enforce, rather than the one that is best for the environment, the animals, and the producers being asked to deliver it.
About the author
Jack Bosworth is a fourth-generation farmer and Director of FJ Bosworth & Sons, an arable and pig farming business at Spains Hall, Willingale, Essex. The farm has been in the family since 1919, and Jack farms alongside his father Stuart Bosworth, who was named Farmers Weekly Pig Farmer of the Year in 2011. The business is Red Tractor assured and runs an integrated farm-to-fork model, with home-grown cereals milled on site using solar-generated electricity. In 2024 the business won the National Pig Awards Sustainable Farming Award.
You can follow Jack’s articles on fjbosworth.com, or get in touch via the WhatsApp link on the site.
Fourth-generation farmer at Spains Hall, Willingale. Runs the contracting team and writes most of what appears here.