Most critters seen DOR (dead-in-road) in our area are possums and armadillos. DOR armadillos are seen mostly during late spring and summer months and possums from October to April.

Until about 10 days ago, when I saw two DOR possums on Wire Road, I had seen only one other DOR possum during the 20011-2012 “cool season.” Several other people I talked to also noticed a dearth of DOR possums. Coyotes are known to prey on possums and compete with possums for dead animals and persimmons as dietary supplements. I wondered if coyotes might be responsible for a decline in numbers of possums, or if a disease of some sort might be responsible.

I googled “possum disease” on my i-Pad, and several items thereto related appeared. I learned that possums rarely suffer from infectious diseases of any kind, but they are the definitive host for a protozoan parasite that can be transmitted to horses. The medical term for the disease when horses are infected is Equine Protozoal Myeloencephalitis (EPM), commonly called “possum disease.” I’d never before heard or read of the disease. It was first diagnosed in the U.S. in 1990.

The mature parasites live within the possums’ intestinal tracts and cause no harm to the possums. Immature infective stages of the parasites, sporocytes, are shed in the possums’ feces and when ingested by the horse in contaminated grass, hay, grain, or water, the sporocytes transform into stages that ultimately enter the horse’s spinal cord, where they begin dividing. Symptoms of the disease include lack of coordination, weakness and spastic behavior, lameness, airway abnormalities, muscle atrophy, and uneven gait in hind legs. Diagnosis is difficult and treatment is complicated. Improvement is seen in about 70 percent of treated animals, but fewer than 25 percent completely recover.

Prevention includes denying possums’ access to hay and grain and picking up road-killed possums found in the vicinity. The disease is not transmissible from one horse to another. Reportedly, possum disease in horses is increasing in frequency of occurrence. It is said to be common in Kentucky and according to the School of Veterinary Medicine in Missouri more cases of EPM were confirmed in 1996 than all other neurological diseases combined.

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The Republican candidates for nomination, all of them, seem determined to alienate environmentalists and public health advocates. Environmentalists do not attempt to compete with the Big Mules of the oil, gas, and coal mining industries in terms of monetary contributions to their respective campaigns, but they may be inclined to shell out some bucks to the candidate who displays a reasonable amount of environmental sensitivity during the months to come before November. And I don’t believe the GOP candidates and their backers know how many environmentalists resent being called eco-freaks, environmental wackos, overeducated tree-huggers, and other derogatory names.

I did a google search of nine environmental organizations and determined that, collectively, their memberships totaled more than 13 million. And that’s not counting the millions who support the World Wildlife Fund, Nature Conservancy, Ocean Conservancy and other international environmental organizations, a majority of whom, I am led to believe, are U.S. citizens.

I may be dead wrong in my belief that the anti-environmental positions taken by the GOP candidates are providing valuable ammunition for President Obama to use against whoever is the party’s nominee. But I know one thing for sure. All the environmentalists I know are sick and tired of hearing the GOP candidates sounding like clones of Rush Limbaugh and Sean Hannity, and they ain’t gonna take it sittin’ down!

Bob Mount is a Professor Emeritus with the Dept of Zoology and Entomology, Auburn Univ. He is also co-chairman of the Opelika Order of Geezers, well-known local think tank and political clearing house. He writes about birds, snakes, turtles, bugs and assorted conservation topics.