Farmers in a five-parish area east and northeast of the parishes where the storm made its landfall Aug. 27 have probably lost 300 to 400 cattle, said Dr. Craig Fontenot, a large-animal veterinarian based in Ville Platte.
He said the swarms are so thick that the vast number of bites leave horses and cattle anemic and bleeding under their skins. The animals also become exhausted from constantly moving in an attempt to avoid the biting insects, he said in a phone interview Wednesday with The Associated Press.
"They're vicious little suckers," he said.
A photo Fontenot took Sept. 2 shows a bull's belly blanketed with mosquitoes.
He said only a few horses and no goats have died, probably because they are generally kept in stalls which can be sprayed with insecticide, while cattle may graze in 50- or 100-acre pastures.
A deer rancher lost about 30 of his 110 animals, many of which had already been sold, Fontenot said.
"He's saying its over $100,000 he lost," the veterinarian said.
Several parishes have begun aerial spraying, which has begun to thin the hordes pushed out of marshes by the storm, agricultural extension agents said in a news release Wednesday from the LSU AgCenter.
"The spraying has dropped the populations tremendously. It's made a night-and-day difference," Acadia Parish agent Jeremy Hebert said.
The insects remain a big problem in Calcasieu and Jefferson Davis parishes, though spraying has reduced the severity a bit, said Jimmy Meaux, AgCenter agent for those parishes.
Livestock deaths from mosquitoes aren't a new phenomenon. Fontenot said they also occurred after Hurricane Lili in 2002 and Hurricane Rita in 2005. Florida and Texas have had similar problems after hurricanes, he said.
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The video above is from reporting before the storm showing a Texas family's efforts to evacuate their livestock.