Steven S. Nicholson | 4/19/2005 10:28:58 PM
News Release Distributed 5/19/04
The recent prolonged period of excessive rainfall across much of the state could lead to health problems for livestock and horses, according to Dr. Steven S. Nicholson, veterinarian with the LSU AgCenter.
"Rain scald, forage toxicity, arsenic herbicide poisoning and diseases like anthrax are a possibility," Nicholson said this week.
Rain scald is a skin infection caused by a fungus known as dermatophilus.
"Frequent wetting of the skin combined with the bites of large flies can result in numerous cases of rain scald on horses and cattle," Nicholson explained, adding that brown crusts or scabs varying in size from a dime to a silver dollar may appear on the neck, back, scrotum and legs of affected animals. The crusts, and hair, can be peeled away leaving a bright red spot, he said.
"There can be extensive sheets of these crusty lesions on calves and foals," Nicholson said, stressing, "This can be a debilitating disease in some animals."
Moving to another potential problem related to the current weather patterns, Nicholson said pasture forages can become toxic during extended wet conditions followed by hot sunny days.
"The toxins probably are fungal in origin, and from previous experience, it appears the affected forage will lose the toxin following the next rain, but hay cut when the forage is toxic will remain toxic," Nicholson said.
The toxic effect is seen as liver damage and a severe skin problem in cattle, according to the LSU AgCenter veterinarian, who said the skin condition is known as photosensitization and is secondary to liver damage.
In animals with the condition, unpigmented skin swells, turns red, looks like it’s severely sunburned and will peel. The skin of the muzzle and teats is especially vulnerable, according to Nicholson, who says affected cows may not let their calves suckle.
The LSU AgCenter veterinarian said another problem – anthrax or charbon, as it is called in South Louisiana, – might appear in livestock if the rains are followed by two or three weeks or so of dry, sunny weather.
"Livestock owners generally know if their pastures are located in anthrax endemic areas," Nicholson said, adding, "Anthrax vaccine is effective in preventing the disease, but antibiotics will interfere with the vaccine."
Since rains tend to fuel the growth of vegetation, weed control along rights-of-ways, canals, ditches and fences likely will be a priority once the rain stops. Nicholson said it is important not to use a product containing arsenic within reach of livestock and horses.
"Cattle are attracted to arsenic spills, and sprayed forages will be poisonous," the veterinarian explained.
Nicholson also urges animal owners to find out promptly why any animals are sick or dying – if such problems occur.
"Although bioterrorism is not anticipated, it is another reason for obtaining a quick and accurate diagnosis," the veterinarian said. "Private veterinary medical service and diagnostic support are available for blood tests, microbiology, pathology, toxicology and consultation."
Contact: Steve Nicholson at (225) 578-2414 or firstname.lastname@example.org