Recognizing and Reporting Foreign Animal Diseases
A foreign animal disease is one that does not occur in the United States and needs to be identified with the help of your veterinarian as quickly as possible.
What are the clinical signs?
Many of the clinical signs associated with foreign animal diseases are similar to those of domestic diseases routinely seen on swine farms. There are two categories of clinical signs that need to be distinguished from disease conditions that are commonly observed in pigs. These categories are:
- those that produce fever, such as Classical Swine Fever and African Swine Fever, and
- those that produce blisters or vesicles, such as Foot and Mouth Disease, Swine Vesicular Disease, Vesicular Stomatitis, and Swine Exanthema of swine.
Disease conditions with high fevers combined with other signs
For conditions that produce high fevers, such as Classical Swine Fever and African Swine Fever, there needs to be a clear distinction between these foreign animal diseases and their specific clinical signs from those of routine conditions. Some of the routine conditions that need to be distinguished from the foreign animal diseases are porcine circovirus associated disease (PCVAD), erysipelas, Streptococcosis, Salmonellosis, and Pasteurellosis.
Some of the clinical signs shown that may be common to all include:
- Red, blotchy skin
- Unusually high number of pigs with high fevers
- Unusually high number of unexplained deaths
- Unusually high percentage of extremely sick pigs
Some of the signs specific to Classical Swine Fever are:
- Irritated, crusty eyes
- Hind limb weakness
- Abortions, stillbirths, weak litters
- Tremors or convulsions in newborn piglets
Many of the signs listed above may show up quickly or be present in the pig for a prolonged period of time and fail to respond to treatment. There are numerous conditions that could cause a pig to have be nonresponsive to certain treatments and result in a loss of body condition and have stunted growth. It is important that the herd veterinarian be involved in these cases so that the appropriate samples are taken and submitted to a diagnostic laboratory for an accurate diagnosis.
Disease conditions with vesicles or blisters
Observance of vesicles or blisters is important, especially located on the mouth, snout, coronary band or between the toes of pigs. The majority of the conditions that produce vesicles on pigs should be suspected as a foreign animal disease (Foot and Mouth Disease, Swine Vesicular Disease, Vesicular Stomatitis, and Vesicular Exanthema) and reported to the herd veterinarian.
The clinical signs are extraordinary and include:
- High fever of short duration
- Reluctance to eat (off feed)
- Whole or ruptured blisters (vesicles) on the mouth or snout
- Whole or ruptured blisters (vesicles) where the skin meets the claw of the foot (coronary band) or between the toes
- Severe lameness and pain when pigs walk
- Reluctance to get up
- Abortions and death of piglets can also occur
When to report these conditions?
If there is an unusually high number of pigs showing a combination of clinical signs from the lists above and they do not seem to respond to routine treatments, the herd veterinarian needs to be contacted. Foreign animal diseases should not be at the top of your list, but should not be forgotten.
Major reasons why your farm may have a foreign animal disease
- You feed table scraps or meat products
- You have been exposed to feral hogs or other wildlife
- You have had visitors from a foreign country recently
For more information, please visit the following Web sites: www.pork.org www.aphis.usda.gov/lpa/pubs/fsheet_faq_notice/fs_ahcsf.html http://www.oie.int/eng/maladies/fiches/a_a030.htm For more information, please search for the following resources on PIG: www.porkgateway.org
House JA and House CA. Vesicular Diseases. In: Straw BE, D’Allaire S, Mengeling WL, Taylor DJ, eds. Diseases of Swine. Ames,Iowa: Iowa State University Press; 1999:327- 342.
Kleiboeker SB. Swine Fever: classical swine fever and African swine fever. Vet Clin North Am Food Anim Pract 2002;18:431-51.
Sanchez-Vizcaino JM. African Swine Fever. In: Straw BE, D’Allaire S, Mengeling WL, Taylor DJ, eds. Diseases of Swine. Ames,Iowa: Iowa State University Press; 1999:93- 102.
Van Oirschot JT. Classical Swine Fever (Hog Cholera). In: Straw BE, D’Allaire S, Mengeling WL, Taylor DJ, eds. Diseases of Swine. Ames,Iowa: Iowa State University Press; 1999:159-172