Blister Beetle: The Invincible Insect

The menace of Blister beetles is alarming. These centimetre long, brightly coloured insects have been known to create problems for us humans, our livestock as well as other insects apart from the extensive damage they do to our crops and plantations. They belong to the family of Meloidae, a plant-feeding group of insects.

These pesky little blister beetles get their common name from the fact that when they come in contact with our skin, they cause red, painful blisters on them. These blisters are the result of the presence of a chemical, cantharidin, which is a defence toxin present in the beetles. This toxin is very dangerous to cattle like horses, sheep and cows and can also be fatal in higher concentrations.

Their main diet source are cultivated plants. Crops like alfalfa, potato, beetroot, tomato and corn are among their most preferred. They gorge on the leaves of plants and cause loss of crops due to defoliation. They are generally found near the perimeters of plantations and croplands, greedily munching on the leaves and tender flowers. Because of their tendency to attack in groups, the damage incurred after an attack by blister beetles is huge and reclamation of crops is extremely difficult.

What makes these beetles extremely tricky to control is that, even after they are dead, their toxins remain active. This makes the use of pesticides against them fruitless because dead blister beetles are just as dangerous as live ones. If animals accidentally end up eating or coming in contact with the dead beetles, they can be severely injured. Horses are especially sensitive towards catharidin with only as much as 4-6 gms of dead beetles being lethal for them, if ingested. The extent of damage caused to the animals can range between short-term poisoning, difficulty in digestion and even death. This is dependent upon the amount of catharidin consumed. Also, because of their potent toxins, they do not have any natural predators that can be introduced to control the insects in the case of an infestation. This makes blister beetle pest management strategies extremely difficult to draft.

The reporting of such incidents, though rare, are very horrifying.

Small, toxic beetles kill 14 horses on Wisconsin ranch
Monday, January 13th 2020, 11:58 AM CST

Steady rains over the summer in Wisconsin caused Cindy Kanarowski-Peterson to purchase six semi-tractor trailer loads of hay from South Dakota and Wyoming farms after the hay at her ranch became unusable. After thinking her problems were solved, disaster struck.
  As the Wisconsin State Journal reports, 14 of her horses were killed by blister beetles. The blister beetle is a bug, that when crushed, secrets a deadly toxin. The beetles also sickened another 100 horses on the ranch. With the infestation making that hay unusable, the ranchers are looking all over the region to keep their 110 horses fed.
  Kanarowski is attempting to warn other ranchers about the dangers of blister beetles. The ranch has an insurance policy of loss of harvested hay due to a fire or tornado, but it does not cover blister beetles.
  Initially, Kanarowski thought the first cases were just colic, but as the problems grew she began to think it was bad grain. Once two of the horses were necropsied they were found to have holes in their stomachs, which is what caused their deaths, according to a local veterinarian. The horses who survived have a good shot at making a full recovery.
  Kanarowski set up a GoFundMe campaign with a goal of $50,000 to keep her horses fed and the veterinarian bills. As of Monday, 454 people have donated nearly $24,000 to the campaign.

Blister beetle infestation in North-eastern Colorado

Large swarms of three striped blister beetles were reported from Phillips County in northeaster Colorado.  Adults emerge from the soil throughout the growing season (May through September), but periods of peak activity vary with the species. Most species are more abundant in July and August. After emergence, adult blister beetles are strongly attracted to alfalfa and other blooming hosts. Adult feeding generally is not significant enough to warrant intervention. However, the presence of blister beetles in fields at harvest, particularly those species that feed in swarms or aggregations, is a concern for producers.
    Blister beetles are a serious concern for hay producers and livestock owners because they produce a defence chemical called cantharidin that is toxic to livestock. Although most deaths associated with cantharidin consumption are reported in horses, cattle and sheep also are susceptible. Symptoms of cantharidiasis include blisters on the tongue and in the mouth, colic, diarrhoea, blood or intestinal lining discharge in stools, and problems with urination or bloody discharge in urine. If blister beetle poisoning is suspected, contact a veterinarian immediately.
    The cantharidin content of blister beetle species varies and thus the risk of livestock losses varies with the type of blister beetle and the size of the animal. Moreover, male blister beetles have a higher concentration of cantharidin than females. Modern hay harvesting practices (e.g., hay conditioners) are believed to have increased blister beetle mortality and to trap blister beetles in hay.
    In addition, cantharidin oil is released when adults are crushed and can contaminate hay even if the adult blister beetles are not present. Wheel traffic over mowed forage, crimping and cutting activity are the primary factors responsible for blister beetle mortality at harvest, whereas raking and baling have been shown to dislodge dead beetles from hay. Visual inspection of baled hay to detect blister beetles is difficult and will not reveal the presence of cantharidin oil.

Though these bugs might seem undefeatable, it can still be combatted very effectively! CTech Corporation has the perfect solution for tiresome pests like blister beetles and countless others. Termirepel™, our green insect repellent will help to drive away the beetles from your gardens, thus eliminating the fear of its toxin being present anywhere near your precious crops or livestock.  

Termirepel™ is an eco-friendly, non-toxic, non-hazardous, non-carcinogenic, non-mutagenic insect and pest aversive. It repels the undesired insects by employing temporary mating cycle hindrance and disrupting its feeding. This happens because the product triggers an extremely unpleasant reaction in the insects who try to eat it and leads to temporary discomfort. When consumed, Termirepel™ blocks vital hormones required for reproduction in the insects. This leads to temporary infertility in them. The insects remember this uncomfortable feeling and associate the smell and taste of the product, leading them to develop an aversion to the product and stay away from everything that is treated with it.

Termirepel™ is available in the form of a spray, liquid concentrate, lacquer, wood polish additive, and masterbatch.

The lacquer form can be applied on fences and wiring around the farms and gardens, thus cancelling the possibility of an infestation. Polymer incorporated with the masterbatch can be used to make containers for storage of produce after harvesting, to prevent infestation after harvest. Films amalgamated with the masterbatch can also be used to cover the plants and crops.

All of these applications will drive away the insect far away from your farms and you can rest assured knowing that there will be no beetles or their toxins anywhere around your farm, produce or livestock.   

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