User talk:Samantha58501

Blister Beetles Blister beetles are common throughout the United States. Several species can be found in the Great Plains during the summer months.

Adults range from 1/2 to 1 inch long and have a char-acteristic narrow, elongate, soft body with a head wider than the pronotum (see figure). The flexible wing covers are rounded over the abdomen and the color varies from black to gray to brown. Some species have a metallic sheen or they may have conspicuous orange stripes.

The larvae of the largest genus Epicauta are considered beneficial, for they feed on grasshopper eggs in the soil. Many species are found in bees' nests where they feed on bee eggs and food stored in the nest.

Problems associated with blister beetles have traditionally been in those areas where environmental conditions favor frequent outbreaks of grasshoppers. This is especially true in the relatively arid states of the west, central and northern Great Plains.

Effects On Horses, Cows etc. All species of blister beetles produce a toxic substance called cantharidin. This toxin is a well-known vesicant (blister-causing substance) that is quickly absorbed upon contact and causes inflammation and blistering of internal and external body tissues. The amount of toxin produced varies considerably between species. The ash-gray, black, striped, and margined blister beetles are a few of the more common species which produce levels of cantharidin capable of poisoning livestock. Livestock come in contact with blister beetles when they consume infested alfalfa hay. Horses are most susceptible to the toxin, while sheep and cattle are more tolerant. The reaction to the toxin depends upon the relative dose; enough ingested beetles can be lethal to any animal.

Researchers have determined the lethal dose of cantharidin to be approximately 1 milligram per kilogram of horse body weight. This means that about 200 blister beetles could have levels of toxin sufficient to kill an adult horse. In addition, an average of 5.0 mg of cantharidin has been found in striped blister beetles, which indicates that 30 to 50 adults could be potentially lethal. However, even a few beetles may cause colic in horses. Cantharidin can also be lethal to cattle and sheep. Although less susceptible than horses, they may experience symptoms if enough beetles are consumed. A laboratory study has shown that cantharidin can reduce the digestibility of certain forages. Little information or research exists addressing the effects of cantharidin on lactating dairy cows. Symptoms of sublethal poisoning include depression, diarrhea, elevated temperatures, increased pulse and breathing rates, and dehydration. There is also frequent urination, especially after the first 24 hours. If cantharid poisoning is suspected, a veterinarian should be contacted immediately.

The toxin is extremely stable. Crushing or chemically killing the beetles will not diminish the toxin's activity. Even the remains or dried juices from crushed beetles on the hay may cause severe digestive and urinary tract ailments in domestic animals.

By: Samantha58501