MOHRSBy Robin Rysavy, DMA, in consultation with Noella Allan, DVM
A common problem often seen in rabbits is the presence of Psoroptes cuniculi (ear mites). These tiny parasites, a member of the arachnid family (includes spiders and scorpions), can cause intense suffering and illness if left untreated. Their life span is approximately 21 days. Psoroptes cuniculi are non-burrowing, and chew and pierce the skin in the ear canal. Sometimes a rabbit caretaker will notice the accumulation of multiple layers of a thin, brown flaky crust on the inside ear of a rabbit. This crust is generally composed of mites, mites feces, skin cells, and inflammatory cells. Often a secondary bacterial infection will develop, which can extend to the middle and inner ear causing torticollis (head tilt) and ataxia (staggering or jerky, uncontrolled movements). In addition, with a severe infestation, the mites may extend to the head, neck, and other parts of the body. These mites cause intense itching, and often rabbits will scratch and shake their heads, which can lead to further trauma of the affected area. Diagnosis is made by a rabbit veterinarian examining some of the debris from the ear canal under a microscope. Also these mites (and/or mite movement) can usually be seen with the naked eye through an otoscope.
Untreated Fur Mites
The treatment most effective is a series of three to four subcutaneous injections of ivermectin at a dose of 400ug/kg, given at 2 week intervals. Ivermectin does not kill the mites eggs, but when used repeatedly at the apporpriate intervals and dosage, it will kill the new generations of mites as they hatch. All rabbits in the household should be treated (even if they are asymptomatic), as these mites are easily spread through direct contact with the affected rabbit, ear debris, or bedding. Psoroptes cuniculi can live for up to 21 days off the host, and will usually contaminate the environment as well when the layers of crusts in the ear dislodge. Therefore the area should be thoroughly cleaned.
Some of the newer topical parasite products such as Revolution claim to be effective against mites, but with the topical treatment, we did not see as good a “kill” as with the ivermectin. Any secondary ear infection should be immediately treated with the appropriate antibiotic (systemic and topical).
SnowPea’s Story
The Missouri House Rabbit Society in Kansas City was asked to take Snow Pea in as a foster bunny by someone who agreed to bunnysit for her original human caretakers while they went on vacation. Upon their return, they declared they did not care about Snow Pea anymore, and decided to abandon her.
The Missouri House Rabbit Society in Kansas City was asked to take Snow Pea in as a foster bunny by someone who agreed to bunnysit for her original human caretakers while they went on vacation. Upon their return, they declared they did not care about Snow Pea anymore, and decided to abandon her.
After getting Snow Pea on Sunday, January 12, 2003, Lori Key (MO HRS Fosterer/Educator)
immediately noticed the brown crust in her right ear, and made an appointment with one of our wonderful rabbit savvy veterinarians. Although Snow Pea was given ivermectin and taken to the vet a couple of days after her rescue, by the following morning she was exhibiting signs of torticollis (head tilt). She was taken back to the vet and put on the appropriate antibiotics.
Untreated Ear Mites
Unfortunately, symptoms persisted and full blown head tilt was the result. Although this could have been a tragedy, this story has a happy ending. Snow Pea, through the expert veterinary care provided by Dr. Jill Sandler, Dr. Brock Exline, and Dr. Pam Truman (acupuncture vet), and with the tender loving care she receives daily from her human “mommy” Jennifer Habernal, continues to improve.
Her road to recovery has been a lengthy one though. This condition began 10 months ago. She received her first acupuncture treatment three weeks after being diagnosed with “head tilt”. The acupuncture sessions continued once a week for ten weeks. Snow Pea is still currently on systemic antibiotics. It is only recently that her head is beginning to tilt less, and her balance is good enough for her to romp through the room where she lives. With continued acupuncture booster treatments, and keeping a close eye on her ears for any more infection, it is expected that Snow Pea will make a full recovery. Her head may never be completely straight, but this will not hinder her from enjoying life to the fullest, and being unconditionally loved by her “mom”.