Living with disease? Pig genetics, welfare and use of antibiotics

This paper explores the dilemma between different ethical ‘goods’, presented by the pressure to reduce the use of antibiotics in pigs, to ensure continued human benefits, at the same time as needing to maintain the health and welfare of the animals. More specifically, can we move from ‘preventing’ disease to ‘living with’ disease in pigs, by selecting for more disease resilient pigs? Interviews and focus groups with 67 pig farmers, vets and advisors suggests that selecting for disease resilience, while desirable, is more complex than appears at first, and needs to take account of the contexts. A number of other factors need to be taken into account: will it reduce the economic performance, the impact on behavioural traits such as tail biting, the relationship between infection and the density of pig farms in an area, what other options are available for a particular disease? Classical selection for improved disease resilience may be thwarted by pathogens mutating to overcome any resistance. Removing the action of one pathogen may also open the door to another. If, on the other hand, pig farmers are to live better with disease, genetics can provide one means of increasing resilience and can be complementary with biosecurity and use of vaccines. The UK pig industry has already reduced the use of antibiotics considerably. How low can these be reduced further without incurring harms to animal welfare? To what extent can the benefits to humans justify harms to animals, given that the link between antibiotic use in animal agriculture and the emergence of antibiotic resistant bacteria in humans is contested and where clarity is yet to emerge? This analysis suggests that framing the question merely as a matter of biology of disease resilience misses many key issues. However, this analysis does not ask the question whether intensive pig production, whether indoors or outdoors is justified, let alone if eating pig meat is right.