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Veterinary student researches wild hogs
MISSISSIPPI STATE -- All veterinary students learn about swine, but one dual-degree major at Mississippi State University is gaining insight from a wildlife perspective.
Camille Harris, a 1995 graduate of the Mississippi School for Math and Science in Columbus, plans to earn her doctorate in veterinary medicine next May. She will earn a master's degree in veterinary sciences with a minor in wildlife the following year. For her master's thesis work, she is studying the blood and tissues from wild hogs in Mississippi to determine viral and bacterial diseases they may carry. She is also looking for specific parasites.
"My main interest in wildlife is in the aspect of invasive species -- those that are not native to the area -- and the impact they can have on an area and native species," she said.
Harris' research has enabled her to interact with wildlife agencies, private landowners, hunters and university personnel outside the College of Veterinary Medicine.
"One of the most exciting aspects of my study has been the opportunity to work with wildlife biologists. Whenever diseases like chronic wasting disease in deer populations come up, the cooperation between agencies is going to be the key to their control," she said.
Harris' work is under the supervision of Dr. Lora Ballweber, associate professor with MSU's College of Veterinary Medicine. Two of the main diseases they are watching for are brucellosis, a bacterial disease, and pseudorabies, a viral disease.
"Brucellosis and pseudorabies are monitored at the federal level in domestic animals as we try to eliminate them in the United States," Ballweber said. "Once out of the domestic populations, it will be essential that we avoid reintroducing the diseases from wild animals."
Among the diseases and parasites they are monitoring, several are zoonotic, or can be transmitted from animals to humans. Some of those problems include trichinosis, cryptosporidiosis, giardiasis, leptospirosis and toxoplasmosis.
"For humans, these diseases and parasites can cause diarrhea, birth defects or abortions," Ballweber said. "They can be transmitted through improperly cooked meat or by swimming in water where hogs have been."
Mississippi has several different ecological zones. Ballweber said they are studying to see differences in diseases from one zone to another and from one season to another. They also are analyzing ticks collected from wild hogs for the presence of diseases such as Rocky Mountain spotted fever and Southern Tick Associated Rash Illness, which is called STARI and is similar to Lyme disease.
Rich Minnis, assistant research professor in MSU's Department of Wildlife and Fisheries, is leading the effort to collect the samples for Ballweber and Harris. He began an in-depth study of Mississippi's wild hog populations in 2002. Three things Minnis and other researchers knew before they started their project were that hogs multiply rapidly, carry diseases and can cause extensive crop and property damage.
"We knew some areas have exploding populations, but didn't know why other areas did not. We knew they are prolific, but didn't know specifics about their reproductive cycles," Minnis said. "The answers to those questions will be the key in managing wild hogs and protecting human and animal populations in the future. Our No. 1 concern is disease transmission. Wild hogs can carry 30 diseases, some that can transmit to humans, domestic animals or other wildlife."
Minnis has been trapping hogs across the state, primarily in undeveloped lands near rivers. Significant populations are in the north Delta area beside the Mississippi River, in South Mississippi and in Noxubee County in east central Mississippi.
"If we have had wild hogs in 82 counties, and that is probably true, why are their numbers exploding in some areas and not others?" Minnis asked. "We plan to study their habitat's impact on them and also their impact on the habitat."
By studying their ecology, Minnis said he hopes to determine the time in their breeding cycle to harvest the animals when it will have the greatest impact on their numbers.
"Because hogs are so prolific, you need to take 75 to 80 percent of the animals in an area to keep a population in check," Minnis said. "Since they have two litters each year, we are not sure how important seasons or other issues are for hunting considerations."
The recreational potential is another consideration for Minnis. As numbers grow rapidly in some areas, the need for effective hunting will increase.
"We tend to know where they are during the hunting season, but we need to know where they go during the summer or when they experience habitat changes from issues such as floods or droughts," Minnis said. "Future research will involve placing radio collars on some Delta hogs to help monitor where they are and to increase our ability to harvest others in their group. We will be able to see what they are eating that may be in competition with other wildlife, such as acorns or turkey eggs."
Eventually, research will turn to the economic impact of wild hogs. On the negative side, hogs cause significant damage to grain and forage crops across the state. If they carried a disease to a commercial hog operation or other livestock industry, the results could be disastrous.
"As awareness and interest grow for hunting wild hogs, the positive economic impact will increase as well," Minnis said.
Contact: Dr. Lora Ballweber, (662) 325-1345