For the love of you pet: Venomous arthropods
By Shana Bohac
July 24, 2014 at 2:24 a.m.
There are many bites and stings that can have serious affects on our pets. Bumblebees, honeybees, wasps and ants are the arthropods that pose the most medical risks.
Bees live in colonies or hives and will aggressively defend the nest as a group. When triggered, bees release an alarm pheromone that attracts other members of the hive. Bumblebees are found in hives of 200 or so members, whereas honeybee hives are comprised of more than 100,000 members.
There are also African "killer" bees that are much more aggressive than the average bee. They will actually pursue a "threat" more aggressively and for extended distances (miles).
The venom from a bee is delivered by a stinger. The stinger actually detaches from the body and kills the bee. Venom is injected into the victim within one minute.
Local, clinical signs of a bee sting include a wheal, which is a red, swollen mark with a central red spot. In many cases, there will be swelling, itching and pain. Systemic signs depend on the number of stings and whether the animal is allergic to bee stings. Allergic death or anaphylaxis can occur from a single sting if the animal is allergic to the venom.
Severe envenomation can result in acute renal failure, muscle breakdown, inflammation of the optic nerve, liver dysfunction, difficulty breathing, clotting abnormalities and death.
In dogs, it has been found that less than 14 stings per kilogram of body weight results in a good chance of survival with proper medical attention. In dogs stung between 14 and 24 times per kilogram of body weight, the patient is considered to be in critical condition and requires aggressive medical treatment. Greater than 24 stings per kilogram of body weight typically results in significant complications, organ failure and, unfortunately, death.
Wasps or yellow jackets can be aggressive alone or in conjunction with a hive. Hive numbers are usually much lower than bees. Venom delivery is via a sting; however, the stinger is not released, and the wasp does not die; therefore, it can sting multiple times.
Local signs are similar to bee stings and include redness, swelling and itching. Systemic signs can include anaphylaxis, acute renal failure, coagulation disorders, swelling of the brain, liver toxicity and muscle breakdown. Medical attention is needed immediately in order to reduce the risk of severe complications.
Ants are colonial and will therefore attack in a group if the victim is near the nest. Ants actually bite the victim and then sting to inject venom. Ants can inject venom up to 20 times with one bite. Local signs develop within three minutes and begin with the formation of a wheal. Vesicles develop within 24 hours and can rupture and cause an ulcer.
Systemic clinical signs can occur in severe cases and include seizures, coagulation disorders and muscle breakdown. Medical attention is required immediately if a severe allergic reaction occurs.
Dr. Shana Bohac has a veterinary practice at Hill crest Animal Hospital in Victoria. She works on both small animals and equine patients. Submit questions to firstname.lastname@example.org.