We’ve got a couple of hogs in with harvest mite infestations now.
Harvest mites attack animals (and humans) during their larval period, which is the only stage that attacks animals. These larvae are present on vegetation and are active during the day, especially when it is dry and sunny. When they come into contact with any warm blooded animal they swarm on and congregate in areas where there is little hair and the skin is quite thin. This usually occurs especially towards the end of summer.
The larva feeds by thrusting its small hooked fangs into the surface layers of the skin, and then injects a fluid to break down the cells. The liquid food resulting from this process is sucked back into the digestive system of the larva. It will inject and suck for two to three days at the same site until it has increased in size three to four times. The larva then drops to the ground to complete its life cycle. It descends into the soil and after about six weeks becomes an eight-legged nymph and then an adult which eats plants and small insects. Eggs laid by the adult in the spring and summer hatch into the six-legged larva (known as harvest mites) and the cycle starts again.
When larvae inject fluid into the skin, this can cause a severe skin reaction in sensitive individuals leading to painful itchy patches of raw skin.
We treat against these mites with a topical application of a miticide.