Pigs are particularly in need of a level of ‘biosecurity’ because they live in herds, often thousands of individuals in close proximity in closed buildings, and are susceptible to a wide range of different diseases which can either seriously interrupt growth and productivity, or at worst wipe out entire herds.
These diseases have various ‘vectors’ – means of spreading – ranging from vehicle tyres and stockman’s clothing to the odd rat, mouse or bird, and even the wind itself.
To protect our stock and our business, keeping everything performing to their economic best, every farm needs a measure of Biosecurity built into its plans.
Let’s start at the beginning. There is a range of infectious agents out there: viruses, bacteria, fungi and parasites being the principal players. They can cause a wide variety of diseases from common colds and inflammations affecting a few individuals to population threatening epidemics. They access their hosts through five ‘pathways’, these being: people (for example stockmen, reps, vets and visitors); pigs (seems obvious, but we’re thinking about individuals brought into a herd from another farm – replacement breeding stock for example); vehicles (bringing in and taking away people, pigs, feed and so on); the environment (wind / water borne diseases, extremes of temperature for example); and vermin (from the farm cat to the ubiquitous rat, and the night-time fox to the daytime starling, rook and chook).
All of these can bring disease of one form or another, and all diseases, by definition cause a negative change in the animal’s physiology, which in turn leads to reduced productivity and therefore a reduced profit (at this point many pig farmers will be laughing, as they don’t often or easily make a ‘profit’ in the UK).
‘Biosecurity’ encompasses a range of measures that can be taken to combat / prevent these pathogens from gaining entry to a very good food source (your pigs) and taking hold of your herd and business.
Three definitions with regard to pig farming would be useful here, I think:
HEALTH is a state of physical and psychological well-being that allows the pig to express its genetic potential for maximising productivity, reproductive performance and lean meat production.
DISEASE means an unhealthy disorder of body and mind, sometimes with pain and unease, that is likely to prevent the pig from exploiting its genetic potential resulting in lowered productivity.
BIOSECURITY is a set of preventive measures designed to reduce the risk of transmission of infectious diseases, invasive alien species and living modified organisms.
So what are these measures? Remembering that you can’t always see a disease, particularly at the early stages of its development; that good Biosecurity is as relevant everyday as it is when there’s a major disease outbreak; and that personal hygiene is as important around livestock as it is at home – then the following are (some of) the things that ought to be considered.
People: only allow people onto the farm who have had no contact with any other pigs for at least 72 hours (some pathogens can hang around on human skin for a couple of days, however much you scrub – and those that stay up you nose are particularly devious: maybe your nose isn’t as complex and interesting as a pig’s, but it feels familiar and a safe place to hide before you can find a nice pig to take hold of through a sneeze, cough or a contaminated breath); only allow people wearing your farm’s Personal Protective Equipment (PPE) onto your unit – the soles of shoes and boots are good transport for all sorts of pathogens wanting to get out and about; use disinfectant footbaths at the entrance c=gate, and preferably between different parts of the farm as well; keep a record of who enters, close and lock gates and keep entrances to a minimum; the ideal is a shower-in / shower-out unit, where only clean personnel wearing pig farm clothes can enter.
Pigs: try to ‘close’ the herd, allowing no other pigs inside – breed your own replacement breeding stock, only use semen from a minimal disease unit; only allow clean, empty, disinfected, vehicles up to a loading ramp away from the main stock buildings / paddocks.
Vehicles: during an epidemic, such as the Foot & Mouth Disease outbreak in the UK n 2001, all stock movements are strictly monitored / controlled, and there are disinfectant soaked sponges and wheel washed at every farm gate. Tyres are a great disease carrier!
Environment: don’t establish a pig unit within five miles of another one, especially down wind; don’t allow pigs to live in an environment that you’d feel uncomfortable in – not too hot, cold, damp or dirty; keep the perimeters intact.
Vermin: depending on your part of the world the list will be a little different to mine, but no less extensive. There are common factors, rats and cats for example, and your local version of our fox and flocking birds like pigeons and starlings. All of these need controlling, which basically means keeping them out, as all can carry something or other from a host outside your herd. At the very least good rodent control is essential!