Clinical signs

They commonly arise from fighting particularly when sows are grouped at weaning. Initially there is a break in the skin which leaves a scar followed by swellings beneath. Abscesses can also arise as secondary infection to other conditions such as swine pox, PRRS, pneumonia or tail biting and if they become widespread throughout the body, the result may be emaciation followed by death or condemnation of the carcase at slaughter.

Diagnosis

This is based on the clinical signs of abnormal swellings under the skin especially with overlying scars. To confirm the diagnosis, feel and press the swelling to ascertain if the contents are fluid or solid and whether they are beneath the skin or deep seated. To examine the swelling more closely, restrain the pig by a wire noose or by heavy sedation (stresnil 1ml/10kg), and sample the contents. This is carried out using a 10ml syringe with a 18mm 16 gauge needle attached. The needle is inserted at the lowest soft point of the swelling and fluid withdrawn. If it is an abscess a white, yellow or green substance of either a watery or a cheesy consistency will appear.

Similar diseases

Haemorrhage into the tissues from a recently ruptured blood vessel or a haemorrhage of long standing is the only condition likely to be confused with an abscess. In such cases either pure blood or a very thin blood stained liquid will be withdrawn. Such pockets of blood are called haematomas and if they have been present for a long time a clot will have formed, in which case only serum or a clear liquid will be withdrawn.

Treatment

• This is aimed at draining the pus. Sometimes it will occur naturally after the abscess bursts but most require lancing or opening surgically. To do this make an incision approximately 15-20mm long at the lowest point particularly where it is soft and fluctuating. A sharp scalpel blade with only 15mm exposed is inserted into the abscess in a downward movement to open it up. Carry this out only when the sow is restrained. A quick controlled movement of the blade will cause little pain, far less than trying to infiltrate a local anaesthetic. The pus should be squeezed out and the interior washed using a syringe and sterile saline solution. Such a solution is made by adding 5 grams of salt to 1 litre of previously boiled water. The wound must be kept open for at least 3 or 4 days or until all the pus has drained out, otherwise the abscess may reform.
• See lancing an abscess or haematoma chapter 15.
• Most of the organisms that cause abscesses in the pig are either penicillin or oxytetracycline sensitive.
• If the area is badly inflamed, squeeze into the hole an antibiotic cream (a cow mastitis tube is ideal) containing penicillin/streptomycin, oxytetracycline, amoxycillin or ampicillin.
• Treatment should be given by intramuscular injection - if the area is inflamed or the sow is ill.
• Medicines that could be used include; Penicillin/streptomycin daily for 3-4 days, Amoxycillin long-acting (LA) every other day, Oxytetracycline (LA) every other day, Penicillin (LA) every other day.