Waste from pork production mosaic
This photo shows faecal waste from intensive farming to produce pork.
Learn more...
PORK
From bacon sandwiches to sausage rolls, pork remains a staple of the British diet.
In 2021, each British citizen consumed an average of 21.1kg of pork, equivalent to 1400 rashers of bacon!
Although this might sound like a lot, pork consumption has actually declined over the past five years. In 2016, the average UK citizen consumed 24.9kg of pork each year, or 1600 rashers of bacon.
Many scientists see this decline in pork consumption as a positive change for our health and the environment.
It has been recommended that the UK aims to reduce its meat consumption by a further 30% over the next decade.
Photo by Andrew Molyneaux on Unsplash
Photo by Wright Brand Bacon on Unsplash
But this decline in pork's popularity has not been replicated the world over.
In China, the world's largest consumer of pork, the amount of pork eaten per person is projected to increase 4% between 2021 and 2022.
Intensive Farming
The term 'intensive farming' is used to refer to farming practices with "high biological and economic productivity" resulting from a "low input of labor, feed, and space per animal".1
Despite a decline in demand for pork products in the UK, the number of intensive pig farms is believed to have grown by 7% between 2017 and 2020.
60% of UK pigs are farmed intensively.
HOG FAECAL WASTE
Many intensive pig farms use slurry-based housing systems. Pigs are fed a diet that causes them to produce liquid faeces, which falls through slats in the floors to be collected in lagoons.
This waste is rich in nitrogen, meaning that it can be used as crop fertiliser.
However, only 17% of the nitrogen found in pig slurry is available to be taken up by crops.
Before the slurry is even applied to the field, 70% of its nitrogen content will be lost into the atmosphere as ammonia.
High levels of atmospheric ammonia can cause problems for rural communities. Not only does the gas have a pungent odour, but prolonged exposure can cause damage to the lungs and digestive system.
What happens to the nitrogen that is not lost to the atmosphere or taken up by crops?
Nitrogen from slurry is liable to drain into groundwater, rivers, and lakes. Excess nitrogen in watercourses acts as a pollutant by causing the overgrowth of algae, also known as 'algal blooms'.
Algal blooms strip watercourses of their oxygen and can result in the mass death of fish.
In 1995, the rupture of a hog faecal waste lagoon in Caroline (USA) contaminated 22 miles of river, causing an algal bloom and polluting the water with high levels of faecal bacteria.
Photo by Brian Yurasits on Unsplash
[1] Maes, Dominiek GD, Jeroen Dewulf, Carlos Piñeiro, Sandra Edwards, and Ilias Kyriazakis. "A critical reflection on intensive pork production with an emphasis on animal health and welfare." Journal of animal science 98, no. Supplement_1 (2020): S15-S26.
Built with Shorthand
