Wild Boars

This gives you some idea of what is involved and why hog factories might be nervous of feral hogs.

There has been little documentation of many of the diseases of feral hogs and their spread to livestock and humans. However, there are two diseases associated with feral hogs that are documented fairly well - pseudorabies and swine brucellosis. Other diseases hogs may carry are tuberculosis, anthrax and tularemia.

Pseudorabies is a viral disease of the central nervous system that can affect domestic and feral hogs and fatally affect cattle, horses, goats, sheep, dogs and cats. Wild animals such as raccoons, skunks, opossums and small rodents can also be fatally infected. Symptoms of the virus in these animals are anorexia, excessive salivation, spasms, convulsions and intense itching followed by paralysis and then death. Pseudorabies is not related to the rabies virus and does not infect people. This disease is of special concern to domestic hog owners because it can weaken pigs and cause abortions and stillbirths, thus decreasing production and profits. Once infected, the hog is a lifetime carrier and will periodically shed the virus through the mouth and nose. Transmission of the disease can be through direct contact, contaminated feed and water, ingestion of infected tissues, or contaminated trailers.

Swine brucellosis can cause infertility in boars and abortions in sows. This disease can also cause a loss of production and profit in domestic swine operations. Swine brucellosis is transmitted through reproductive discharges such as semen and afterbirth and once infected a hog is a carrier for life. The only effective way to control this disease is to test and remove infected individuals, a task impossible to do in a wild population. Swine brucellosis is contagious to humans and symptoms may range from severe flu-like symptoms to arthritis or meningitis. There is no cure for this disease in animals while humans can be treated with antibiotics in an attempt to clear the infection.

The main reservoirs of tuberculosis infection are in man and cattle, however feral hogs have been found infected with (Mycobacterium bovis) the same strain of tuberculosis found in man and cattle. Although the M. bovis strain has been detected in feral hogs, they are not very susceptible. The infection is most often contracted by ingestion of infected materials. Lesions on the lymph nodes are good indicators of an infected hog. Fortunately, due to extensive control measures, this disease is not common. Feral hogs may also carry another strain of tuberculosis, M. avis, contracted by eating dead birds. This strain is not contagious to humans.

Anthrax is a serious soil-borne disease that is most commonly associated with neutral or alkaline soils that serve as reservoirs for the organism's spores. Recognized endemic areas include portions of Texas, Louisiana, California, Arkansas, Mississippi, Nebraska, South Dakota and small areas in other states. Even within these areas, anthrax occurs irregularly and primarily when the minimal daily temperature is above 60 degrees. Although uncommon, the feral hog may become infected when feeding. Humans can contract this disease from contaminated animals or soil. The disease in humans is often fatal if not promptly treated with antibiotics.

Tularemia is not commonly found in feral hogs but they can contract it through direct contact or ingestion of contaminated animal carcasses. Ticks are a good vector as well as a reservoir and the most common source of infection for man. Persons who dress, prepare or eat improperly cooked feral hogs or other wild game are also at increased risk.

Feral hogs harbor several parasites some of which might pose problems for man or other animals. Fleas, hog lice and ticks are some common external parasites that a hog may acquire. It is thought that feral hogs do not occupy an area long enough or in sufficient numbers to get infected with large numbers of internal parasites or facilitate transmission to humans. However, internal parasites can occur in feral hogs and may include roundworms, kidneyworms, lungworms, stomachworms, whipworms, liver flukes and trichinosis. Trichinosis infections in humans are established by consumption of undercooked, infected pork. Ranchers, farmers and hunters need to be aware of these potential diseases and take every precaution to avoid infection. Livestock owners should be sure all of their animals are vaccinated, especially when there is a chance they may have contact with feral hogs. There are state and federal laws governing the transport and relocation of feral hogs. Blood tests are required by law before feral hogs can be relocated. Hunters, trappers, butchers and wildlife managers should always wear rubber gloves when handling or dressing feral hogs. Try to avoid contact with reproductive organs and blood, and wash thoroughly after contact. Hunters and chefs cooking feral hog meat should make sure it is thoroughly cooked.

Summary

Feral hogs represent many unknowns to biologists, wildlife managers, landowners and hunters, and as one biologist so precisely put it, "feral hogs are an ecological black box." Feral hogs in some areas have been credited with the perceived decline of the quail population, yet there are other areas where quail numbers are high and feral hogs are everywhere. They also receive credit for having a significant impact on wild turkey nests, various plant species and entire ecological systems. However, the actual effect hogs have on our environment remains unknown. More research and practical knowledge are needed to give us a better understanding of the feral hog and its influence on game and non-game species as well as the environment and its ecosystems. We do know feral hogs can harbor and transmit some diseases and parasites to livestock and humans. We know feral hogs can have a significant negative impact on some livestock operations through depredation and damage to facilities and fences. Farmers also share a significant portion of the damage caused by the rooting of fields and depredation of crops. Feral hogs provide excellent table fare, represent a challenging game species to pursue with weapon or dog, and compete with the white-tailed deer in some areas as the most popular animal to hunt. As mentioned, there are many pro's and con's regarding the status of feral hogs and there always will be as long as we have biologists, farmers, ranchers, hunters, and of course, the feral hog.