Most of us would suspect deaf and blind dogs have different behavioral traits than dogs with good hearing and vision? Not so, research finds they are very similar to dogs with normal hearing and vision.
No one knows exactly how many dogs have hearing or vision problems. Congenital deafness and/or blindness occur in several breeds. In some cases this is related to coat colors — for example, the double merle gene in Australian Shepherds is linked to deafness and blindness — and at other times not, as with inherited cataracts in many breeds. Very little is known about how dogs with inherited or acquired vision or hearing disorders behave, which was the motivation for this study by Valeri Farmer-Dougan of Illinois State University.
The results showed many similarities between dogs with a hearing or vision impairment (HVI) and those without. This shows that HVI dogs can make good family pets. In fact, the non-HVI dogs were rated as more aggressive and more excitable than those with HVI. There were also some differences in specific behaviors: non-HVI dogs were more likely to chase rabbits, and eat feces (or roll in it), whereas the HVI dogs were more likely to bark too much, lick a lot, or chew unsuitable objects.
The scientists say, “The increased chewing, excessive barking, and increased self-licking reported in the HVI dogs may be due to differences in sensory input compared to non-HVI dogs. Indeed, all the excesses in behavior appear to be self-stimulatory in nature.” Because they asked owners about any other health issues, they do not think health is the cause of this difference. Instead, they think the dogs are making up for the lack of input from their ears or eyes with behaviors that engage their other senses.
This suggests owners of dogs with hearing or vision problems should make an explicit effort to make sure their dog has enough sensory input. The researchers suggest enrichment with toys, including vibrating toys, Kongs, and chew toys, as well as training sessions to engage the dog’s brain. Many such dogs can also attend agility or obedience classes.
The survey was completed by the owners of 461 dogs. The hearing-impaired and vision-impaired dogs (HVI) were considered as one group since there were no differences between them. Ninety-eight dogs were deaf or had a hearing impairment, 32 dogs were blind or partially-sighted, and 53 dogs were both deaf and blind (183 dogs in total). The remainder was a comparison group of dogs without such impairments.
The survey asked owners questions about the breed, training methods used, and information about any disabilities the dog had.
Blind and deaf dogs are excluded from many rally and obedience programs (with notable exceptions). The authors say, “Given that no evidence was found for increased aggression, it seems that HVI dogs could successfully participate in these additional socialization opportunities. Opening up these opportunities would increase the available activities for HVI dogs. Increased opportunities for training and competition increase the general health and well-being of all dogs.”
The authors conclude that, “Through cooperative partnerships between veterinarians, behaviorists, and owners, HVI dogs can be excellent and well-loved companion dogs.” These results will be especially helpful to owners and potential owners of dogs with hearing or vision impairments.
Sources: Canine Inherited Disorders Database