This article first appeared in the March 2020 Pig World Building Supplement under the title of “Taking Our Share of The Burden”.
AM Warkup’s Nick MacIvor assesses the balance between productivity and environmental concerns
We live in interesting times, according to industry veteran Nick MacIvor, now a consultant for AM Warkup. There is a national post-election and post-Brexit ‘let’s grasp the opportunity’ attitude, but this does not appear to extend to livestock producers, especially in the face of the high-profile anti-meat agenda at the start of the year. The way forward ‘seems to be confused’ at present, he suggests.
“There are also mounting environmental issues facing mankind and the more serious-minded individuals realise that waiting for the others to blink first is no long term solution. Livestock farming has to shoulder its share of the problem and at worst be aware of that responsibility and at best do something about it,” he said.
“All production processes have unwelcome but inevitable impacts on the environment. It is the success of managing these impacts which makes the processes acceptable and viable for the-long term. Livestock production is one of these.
“There is conflict, and whilst it may seem that is rooted in the peddling and attempted imposition of lifestyle choices, it stems much more from the clash between the need for protein to feed a rapidly rising world population set against the imperatives of developing carbon neutral production systems, whilst maintaining the wellbeing of the animal being farmed: a complex multi-faceted conundrum.”
Mr MacIvor highlighted the importance of accurately measuring the scale of the issues producers face – illustrated by an example currently playing out in the pig industry. Around 25 years ago, an attempt was made to measure emissions from pig buildings, with results used to calculate values used in ammonia modelling.
But while building designs and practical pig farming have moved on, those values have not. Recent measurements, currently being repeated for verification, indicate that emissions from modern pig buildings could be as low as 50% of the original figures, on a like-for-like basis. “If, as is expected, this is confirmed then at least one of the mountains we face could prove to be only half as high,” Mr MacIvor said.
Another mountain he highlighted is the demand for cheap food and the clash with the costs involved in reducing environmental impacts.
There are, however, ‘significant’ gains to be made in several areas in pig production. “It is believed that given ideal conditions there is as much as 40% production potential in the pig alone still to discover. You may say, in practical terms, that that is impossible to achieve – but all units leave un-utilised or lost potential on the table.”
In Scotland each year a monitor pig farm is chosen and studied, with all aspects recorded, analysed and discussed by producers and specialists all co-ordinated by Quality Meat Scotland.
Mr MacIvor said: “It is significant that each of these farms, typical examples of the majority of pig businesses, show a marked improvement in performance during their periods in the spotlight.
“As I write, Richard Longthorp is on Countryfile emphasising the importance of training in agriculture. A knowledgeable and engaged workforce is of paramount importance and measurable value.
“In order to achieve these goals we have to provide the infrastructure, new or updated, and the time to record and benchmark performance, implement improvements and provide the training, both on farm and off, and career structures which reward excellence.”
The industry is currently in a cycle that favours either the improvement or replacement of finishing accommodation, which Mr MacIvor said was ‘understandable’ given that it takes six times as much feed to finish a weaned pig as it does to get it there – with associated environmental impacts similarly weighted.
“It is therefore not surprising that technology has favoured numbers and survivability pre-weaning and efficiency and environment post-weaning,” he said.
“The win sought here is to improve these two whilst lowering environmental impacts. As has already been mentioned there are other factors working in our favour. Lower than expected building emissions can be added to more targeted feeding regimes, accurately feeding the pig its dietary energy requirement, which will ease short-term pressures for radical change.”
Change will inevitably have to be faced, so apart from those already mentioned, what is available to help?
Air cleaners, using either chemical or biological (or both) filters are an expensive but effective method of removing both gases and some odour from piggery exhaust air, he added. Fitting these systems usually requires design or structural alterations to the building.
The need to exhaust the air in one area, the side or ends, requires some ducting, especially in larger buildings. In addition, there are running costs to factor in. Some jurisdictions currently allow partial cleaning to lower, rather than eliminate emissions, resulting also in lowered costs.
Slurry acidification prevents the release of ammonia and other greenhouse gases. The system is, like air cleaning, expensive to install but has the benefit of a financial return on investment.
The retention of ammonia in the slurry, both during storage and spreading, not only increases its value as a natural fertiliser, but gives it an enhanced cash value. In addition it eliminates it from the attention that is going to inevitably be focused on the release of stored gasses during slurry spreading or incorporation.
Cooling stored slurry below slatted pig buildings is new to the UK, although well tried and tested elsewhere. Reducing the temperature of slurry reduces emissions and produces heat in the form of hot water. If the waste heat is used commercially, then the process will attract RHI (renewable heat incentive) payments which can be set against capital costs. Most typically the resultant hot water is used to heat pads in farrowing houses and floors (or rooms) in weaner houses. The generation of this heat is a low carbon process and could have other implications for UK pig farming in the near future.
There is a trend over time to lower stocking rates and this could be accelerated if entire tails become a requirement. At times, finisher buildings could struggle for heat and the slurry below could become a handy source. In hot countries, the cold side of the process is used to cool floors in service areas and boar pens. UK pig farming is already experiencing summer temperatures where cooling would be of benefit.
Slurry cooling is relatively easily retrofitted in most slurry tanks and even if not currently required, the incorporation of the cooling tubes in slurry tank bases could future proof new builds.
Another option, also easily retro-fitted, is electronic particle ionisation (EPI), charged particles, ranging from coarse particulates to gas molecules and pathogens, in the air within the building that stick together and either drop out of the air or adhere to walls and other earthed surfaces and stay there.
Once the room is de-stocked the ventilation is switched off and the prewash soakers switched on. The ammonia rich dust is washed into the slurry which is disposed of in the usual way. During occupation the dust levels in the air are significantly reduced giving much better air quality benefiting pigs and humans.
Mr MacIvor added: “It may seem counter-intuitive but adversity actually stimulates both change and progress. Building and equipment manufacturers have, and will, always play their part.
“The products and the technology are available. As ever any business requires sensible, informed and sustained investment with improving facilities run and exploited by properly trained and well-motivated people. We will always respond to our customers’ requirements enabling them to overcome problems and find solutions to meet their aspirations, hopefully helping to create the profitable businesses so vital for the future.”