How to read pig signals to detect disease early

Pig producers who learn to read the body language of their herds will improve performance and reduce antibiotic use, according to a leading pig specialist.

Bob Stevenson, a vet who has taken a special interest in pigs, encourages keepers to be aware of key physical signs – signals – that indicate when a pig is unwell or unhappy.

See also: Male pigs grunt less in poorer conditions, study finds

Pigs often disguise their true signs and symptoms of illness because they are group animals.

“If they show obvious signs of illness, they become a weaker animal in the eyes of the group and tend to get bullied,’’ Mr Stevenson explains.

“As such, pigs have an ability to pretend that everything is OK when it is not. Therefore there can be a lot of misunderstanding about whether they are in pain.

“By observing and working out what is normal behaviour, it is often possible to identify if a pig is ill even before the animal shows this itself.

“The aim is to catch pigs that are one-degree ill, not five degrees under when it is too late in the day.’’

Much of this should be done when a pig is not aware that it is being watched. “Quiet observation is crucial – the whole essence of gleaning is that you haven’t disturbed the pigs,’’ Mr Stevenson suggests.

Benefits

Tuning in to a pig’s signals enables early detection and a move away from a just-in-case approach to antibiotic use. And a healthy and happy pig will always perform better.

By observing early signs, prompt action can be taken to separate the animal from the rest of the herd or to treat in situ. “Observe, mark as necessary and take action,’’ Mr Stevenson recommends.

“If a pig is separated there is a risk that it will be attacked when reintroduced, so if the illness is moderate, the best approach maybe to treat in the group. But if a pig has a nasty infection, separation will outweigh everything else. It also takes away the competition for food and water.’’

Mr Stevenson outlines six tips for observing pig signals:

1 Coughing and sneezing

Any coughing or sneezing over and above what is considered normal are strong indicators of whether a pig is ill or its environment is poor. Mr Stevenson advises farmers to count the number of coughs and sneezes in 30sec periods.

Listen before you open the door to the housing. Counting gives a measure of what is normal and what isn’t. If lungs are in excellent order and there are no underlying respiratory diseases that prevent lungs from coping with the burden of dust particles, the normal clearance cough will be very occasional. In a group of 10 pigs you may get a couple of coughs, but not persistent spasms.

2 Sound

Listen to the pig’s voice to see if they’re anxious or stressed. Listen to the volume, the pitch, and the repetition. If that voice has changed, it could be a signal of pain.

3 Movement

Watch for the way they are moving, look at the way the pigs are rising, and how they sleep. “The way pigs lie will provide information about the temperature in the pen. If too cold, pigs are likely to huddle and pile. If too warm, pigs are likely to lie apart from the others.’’

4 Appearance

A pig’s appearance is also good barometer of their health and well-being. To detect dullness in pigs is quite an art, says Mr Stevenson. Signs include a pig with its head slightly down, incorrect posture or persistently limp tails.

5 Smell

Use your nose to pick up on diahorrea or a poor environment.

6 Air flow

“If you wear glasses and they steam up in the housing, perhaps there is not enough air? The tendency is to keep pigs in a very warm environment because they grow better, but that can lead to pneumonia.’’