Many swine disease outbreaks occur every year and are most often related to a large number of pigs raised in the same area or facility continuously. Raising and producing a numerous amount of pigs can result in overcrowding which can then result in pigs who are disease carriers. These disease carriers can continue to infect and re-infect a swine producer’s herd. Without knowing or realizing that the hogs are infected the diseases can travel from swine farm to swine farm introducing new diseases into their swine herds which can produce more carriers.
African Swine Fever:
One of the most destructive diseases in swine known worldwide is the African Swine Fever, or ASF. ASF is a viral disease which affects both wild pigs and domestic pigs. The disease is often contracted when pigs consume uncooked food scraps and contaminated garbage or water. There are many symptoms of African Swine Fever, some of which include reddening of the ears and snout, bloody diarrhea, high fever, skin blotching and abortion frequently occurs in pregnant sows. Fatality is a very common outcome from contracting ASF. If death does not occur, the surviving pigs can carry the virus for months on end. There is absolutely no treatment or vaccine that exists for a cure of this disease.
The main prevention method for the African Swine Fever virus is to be sure that all garbage fed to pigs is thoroughly cooked. ASF is a disease that can be very contagious if it is not controlled. Those pigs that become infected should be eradicated by slaughter and disposing of the carcass by burning or burial. One positive aspect of African Swine Fever is that humans have yet to transmit it.
Porcine Reproductive and Respiratory Syndrome:
Porcine Reproductive and Respiratory Syndrome, or PRRS, is of great importance as one of the most crucial diseases to keep out of United States’ swine herds. In 1992, a Texas swine herd became infected with PRRS. The results were devastating:
• Sows farrowed five days early, with all piglets dying
• Weak, stillborn, and mummified piglet numbers dramatically increased
• Healthy unweaned pigs sickened and died
• Nursery piglets suffered up to 25% mortality
• Pneumonia increased significantly
There are two different types of PRRS-European and American-with nearly 20 variations of the virus. The virus that causes PRRS was first discovered in the Netherlands in 1991. However, evidence suggests that PRRS was not in the United States until 1986. It is now thought that PRRS is a world wide disease.
The disease is spread by pig to pig contact through mucus, excretement and semen. It is also possible to be spread by aerosol (airborne) infection. Young pigs (unweaned) are contagious for up to five weeks after infection. Older pigs are highly contagious for two to three weeks. Tests are still being done on semen to determine how long the boars are contagious. Experimentally infected boars shed the virus into the semen for up to forty-three days. Gilts artificially inseminated then developed the virus.
Aside from the symptoms mentioned above, tests are needed to know if PRRS is in the swine herd. Blood sampling and lab testing of a representative sample of the breeding stock may allow detection in a herd. On average, it takes about ten days of the virus to be present before the tests will be positive.
In order to avoid getting the disease in your herd simple steps should be taken.
• All animals entering the premises should be isolated
• Nursery and breeding facilities should be allowed to rest for two to three weeks between groups
• Sample all breeding stock on arrival and after sixty days of isolation.
Foot and Mouth Disease
Another highly infectious disease found in pigs is foot and mouth disease (FMD). Those that are affected by foot and mouth disease are cloven-hoofed animals. Although on the positive side, this disease does not affect humans or their health. Foot and mouth disease is spread by direct contact with any sort of infected animals. FMD has been around for a long period of time although the last time foot and mouth was in the United States was in 1929. In 2001, to help prevent foot and mouth disease from entering the United States the government prohibited importing animals and their products from those countries with a high risk of having foot and mouth disease.
With disease outbreaks occurring frequently every year, it is crucial to be knowledgeable of deadly or devastating diseases. Diseases can wipe out a producers yearly income as well as ruin their reputation as a swine producer. With more knowledge about possible swine disease outbreaks, a disease can be detected at an earlier stage making the outbreak less devastating.
The following links can provide access to more information on Swine:The Other White Meat!:
Health Management Tips for Disease Prevention
African Swine Fever: A Foreign Threat to U.S Hogs
Porcine Reproductive and Respiratory Syndrome
Amass, F. Sandra (2004) Procedures for preventing transmission of foot-and-mouth disease virus by people. The Veterinary Journal, 103, 143-149
Chae, C. (2005) A review of porcine circovirus 2-assoiciated syndromes and diseases. The Veterinary Journal, 169, 326-336.
Hulten, F. (2004) Evaluation of environmental and management-related risk factors associated with chronic mastitis in sows. AJVR, 65, 1398-1403.
Walker, Randy (1992) Swine: Swine Health Program. The Institute of Food and Agricultural Sciences. Retrieved from http://edis.ifas.ufl.edu/pdffiles/AA/AA080500.pdf
Olega-Perez, A. (1990) Distribution and biology of Ornithodoros erraticus in parts of Spain affected by African swine fever. The Veterinary Record, 126, 32-37.