Lameness is a common cause for culling sows second only to reproductive failure. Cases can occur at any time during the dry period or in lactation. Increased unplanned culling for lameness increases the non productive sow days so reducing the litters per sow per year. Often problems involve first parity or second parity animals before they have reached the most productive part of their life. Sows culled for severe lameness have to be shot on the farm because they should not be transported.
Lameness is prevalent in growing pigs with levels ranging from 1 to 5%. If more than 2% of pigs are recorded lame per month further investigations are necessary.
Lameness can account for significant losses in growing pigs either because the pigs are unfit to travel on welfare grounds and require to be destroyed, or they are part or totally condemned at slaughter. Early identification of lame animals and their removal to hospital pens for treatment is a vital part of the control and healing process.
Symptoms
Sows
- Pig off food.
- Sometimes fever.
- Reluctance to stand.
- Swollen joints / Fractures.
- Evidence of other diseases.
- Loss of balance.
- Arthritis.
- Dog sitting position.
- Not accept boar at mating.
- Pig shows pain / discomfort.
Piglets
- As for sows.
- Shivering.
Weaners & Growers
- Pig may be off food.
- Sometimes fever.
- Reluctance to stand. Difficulty moving.
- Swollen joints / Fractures.
- Evidence of other diseases.
Causes / Contributing factors
The common ones *
- Arthritis caused by bacteria. *
- Back muscle necrosis – a stress related disease.
- Bursitis.
- Bush foot. *
- Cuts or breaks in the skin related to sharp projections.
- Damage to nerves.
- Erysipelas. *
- Fighting.
- Foot-and-mouth disease and swine vesicular disease in those countries where they occur.
- Fractures. *
- Gl?ssers disease.
- Haematomas.
- High stocking densities.
- Laminitis (inflammation of the tissues attaching to the hoof).
- Leg weakness or Osteochondrosis. *
- Mycoplasma arthritis. *
- Myositis (inflammation of muscles).
- Nutritional deficiencies.
- Osteitis (inflammation of bone).
- Osteochondrosis (degeneration of bone growth plate and cartilage).
- Osteomalacia (softening of bone, calcium and phosphorus deficiency).
- Osteomyelitis (inflammation of bone and bone marrow).
- Osteoporosis (weak bones, imbalance of calcium and phosphorus).
- Penetrated sole.
- Periostitis (inflammation of the membrane around bone).
- Poor floor surfaces. *
- Porcine stress syndrome associated with the halothane gene.
- Separation of the head of the femur.
- Separation of the muscle from the pelvis.
- Split horn (poor hoof quality).
- Tail biting (see vice – abnormal behaviour). *
- Torn muscle and/or ligament. *
- Trauma. * (Stocking density and mixing are the two major factors that precipitate traumatic disease).
Diagnosis
This is based on the clinical signs.