For all districts
Abscesses in goats
FIRST PUBLISHED SEPTEMBER 1981
By C.M. Bunn, Regional Veterinary Officer, Bendigo
What is an abscess?
An abscess is a local collection of pus within a tissue or confined space in the body. Abscesses are usually produced by the seeding of a tissue or a space by bacteria. Occasionally if an irritant substance is injected an abscess will form.
Pus is composed of large numbers of white blood cells produced by the animal in response to the foreign material. Acute abscesses are firm and hot swellings. As they become chronic the swelling becomes harder.
Abscesses in goats may be due to many causes. The most important is the bacteria Corynebacterium pseudotuberculosis, which results in the condition known as 'cheesy gland' or 'caseous lymphadenitis' (CLA).
This is a chronic disease associated with abscesses forming in lymph nodes. It is insidious and will slowly spread throughout a herd. In Australia it has been reported as becoming more widesprad in the last few years. A prevalence of 5% has been reported in feral goats slaughtered in a New South Wales abattoir.
The main clinical sign is the development of noticeable swellings in the head, neck and shoulder regions. Abscesses vary in size from the size of a ping-pong ball to the size of a grapefruit.
The pus is either a thick, greenish, soft material or it is in layers of dried cheesy material (cheesy gland). There is generally a thickened capsule surrounding the abscess. Occasionally abscesses can appear on the surface of the udder, and have been reported to reach up to 80-120 mm in diameter.
Generally cheesy gland causes no apparent ill effects. However, it may spread to involve the lungs and other internal organs, with subsequent ill-thrift and even death.
The organism is known to be able to survive in cool shady areas for up to 18 months. Transmission is by contact. The most common method is by contamination of wounds, particularly during shearing. Goats browse on trees and shrubs. Branches, bark, thorns, and awns of seeds penetrating the mouth cavity or damaging the skin around the head, are the reason why so many lesions are seen in the head and neck area in goats compared with sheep.
Treatment involves opening the superficial abscesses and allowing them to drain. The abscess should be flushed with suitable disinfectant (one part of chlorhexidine in 10 parts of hydrogen peroxide is recommended) and then treated with locally applied antibiotics (for example, preparations to be inserted into the udder).
No abscess will heal unless the pus has been removed. It is a waste of time to treat animals with antibiotics unless the abscess has been drained.
Goat producers can prevent or reduce occurrence of cheesy gland by avoiding injuries to goats and practising good sanitation. All wounds should be washed with disinfectant, pus should be disposed of and not left on the ground, and all equipment should be well washed and disinfected.
Sequential shearing should be practised, with the youngest goats being shorn first to prevent the spread of disease from older to younger animals. Recent developments indicate that an effective vaccine may soon be available. (Is now available - Ed.)
Abscesses due to other causes
Other organisms can cause abscesses in a variety of locations. Most are bacteria that are opportunists; that is, they present normally in the goats' environment and enter through an injury.
The table shows the common types of abscesses that occur in goats.
As in the case of cheesy glands, treatment of all abscesses involves opening the abscess, disinfecting the area, providing adequate drainage, removing all foreign
material (such as grass seeds) and applying antibiotics locally.
Prevention depends on good hygiene and reducing the chances of injury.
© 1981 Vic. Dept. Ag.