Background and history

The conditions commonly referred to as “joint ill” is more correctly referred to as an arthritis affecting one or more joints, usually in young pigs.

It is a condition seen in the young of most species and results from infection gaining entry to the blood stream at or soon after birth, circulating around the body and then settling out in the joints.

Occasionally it can settle in other parts of the body, particularly the brain, causing meningitis.

Clinical signs

• Piglets carry a leg, or reluctant to stand
• Piglet may dog sit.
• Inability to compete for a teat will mean poor or starving pigs.
• Visible and palpable swelling of specific joints occurs:
  • hock and knee are most commonly affected.

Diagnosis

This is based on clinical signs.

Causes

The cause of joint ill is bacterial infection of the piglet. The majority of cases are caused by opportunist infection from the environment with, for example, E. coli, staphylococci and streptococci. There are specific infectious agents that can produce epidemics of joint ill (and meningitis) such as strep suis type 14.

There are a number of possible routes by which the bacteria can gain access to the blood stream and, hence, spread to the joints:

• Through the navel
• Through badly clipped teeth
• Through contamination of a docked tail stump
• Through wounds or abrasions
• Through the tonsil of the piglet (especially strep suis).

Prevention

The key to controlling joint ill is firstly to improve hygiene in the farrowing area and secondly to identify and rectify the route of entry of infection.

• Teeth clipping – Teeth must be clipped singly with clean sharp clippers or ground off. Some producers stop teeth clipping in the face of joint ill problems but it must be remembered that the fighting damage that results can itself lead to joint ill!
• Tail docking – Always use separate instruments from those used to clip teeth. Ideally, use thermocautery. Tail stumps can be dipped or sprayed with iodine immediately after docking.
• Navels – Navels should be dipped in iodine at birth.
• Use of dry disinfectants in the farrowing pens can help but are not a substitute for a failure to wash and disinfect or to keep the pen clear of sow faeces. Do not allow sows to spend more than 5 days in the farrowing crate before farrowing.
• Where tonsillar penetration is suspected, and in particular with strep suis 14 infection, prevention can be achieved by:
  • Routine treatment of piglets at birth with long acting penicillin or amoxycillin.
  • Treatment of the sows in the farrowing area with appropriate antibiotics, either by inclusion in the feed or by top dressing onto the feed.

Treatment

Early individual antimicrobial treatment is essential if a recovery is to be made. The medication used should be tailored to the needs of the farm and laboratory testing of the cause(s) may help. In general, penicillin, ampicillin or lincomycin are likely to be effective. Use of pain killers (e.g. ketoprofen) may also be indicated as this condition can be very painful.

Treatment should be continued for at least 3 and preferably 5 days.

Failure to respond and evidence of burst abscesses from joints should lead to culling. In rare cases an early problem with joint ill can contaminate the end of the bone and affect the growth plates with the result that later in life (e.g. at three months) spontaneous fractures occur.