SYMBIOTIC ACARIASIS OF THE EAR IN DOGS. OTA- 

 CARIASIS. EPILEPTIFORM OTACARIASIS. 



Otacariasis in dogs, in packs, and less often single dogs. Symbiotes Au- 

 ricularum v. Canis. Symptoms: Shakes head, scratches ear, debris in 

 meatus, red, raw, ulcerated patches, nervousness on exertion, yelps, runs on 

 obstacles, falls in fit, is sullen, snappish or dull, stupid, deaf. Attacks get 

 progressively worse. Attacks all ages. Find parasite in cerumen. Treat- 

 ment : Syringe out with soapsuds containing 2 per cent, phenol, then inject 

 naphthalin, ether and olive oil, or carbon bisulphide solution, or lysol. 



This has been noticed especially in dogs kept in packs or num- 

 bers, packs of hounds, sporting dogs, but this is manifestly due 

 to the facilities offered for the transmission of the parasite. It 

 has also been seen in setters, pointers, terriers and poodles. 



The es,sential cause of the affection is the Symbiotes Auricu- 

 larum var. Canis, the ovigerous female of which is .46 to .50 

 mm. and the male .35 to .38 mm. in length. 



Symptoms. The dog may show a special disposition to shake 

 the head or scratch the ear, and the examination may show a 

 dirty condition of the interior of the concha, and a discharge or 

 an accumulation of scurf or debris in the external auditory canal. 

 In some cases there is ulceration or red raw patches. Usually, 

 however, the first symptoms noticed are the nervous ones. The 

 dog in the kennel appears well, and he enters eagerly on a hunt, 

 but in fifteen to thirty minutes he utters a yelp or a howl, aban- 

 dons the hunt and runs wildly, striking blindly again.st obstacles 

 and howling, and finally, after describing two or three circles, 

 falling in an epileptic fit. Soon the spasms cease, but dulness 

 remains, and hunting may or may not be resumed, according to 

 the violence of the attack. Examination of the ear shows the 

 accumulation of brownish ceruminous debris, in the midst of 

 which the activelj' moving symbiotes may be detected. 



Like all forms of acariasis the malady is progressive, the at- 

 tacks come on sooner after the dog is put to work, and are more 

 violent and prolonged, and the recovery is less perfect. The dog 

 is sullen, snappish or timid, and stupidity and deafness are not 

 uncommon. Death may occur during a fit. 



Diagnosis. From epilepsy due to other causes, this is dis- 

 tinguished by the shaking of the head and rubbing of the ears, 

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