how humans talk to dogs
Researchers have recently found that puppies reacted positively and wanted to play when researchers in France played them a tape of phrases like, “Who’s a good boy?” spoken in a high pitched way. However, the international team of researchers found that adult dogs ignored this kind of speech.
When we talk to dogs, we often speak slowly in a high-pitched voice, similar to the way we talk to young babies. The researchers think this way of talking may be our natural way of trying to interact with non-speaking listeners, but it makes no difference to adult dogs when we speak to them in this way.
Deafness in pets
There are three types of deafness in pets
- Congenital i.e. The animal is born deaf
- Sudden acquired – some illnesses/ poisons/ can cause deafness in an adult animal that has previously had normal hearing
- Gradual age-related acquired – this is most common, and is nearly always seen as pets grow older
Older pets tend to adjust to the gradual onset of deafness so it is generally not a huge issue: they just become slower, less active and less responsive as part of the ageing process. In contrast, congenital deafness or sudden acquired deafness has a profound effect, and owners need to be careful to ensure that their pets’ quality of life does not suffer as a consequence.
Congenital deafness in pets
The most common cause of deafness in pets is linked to absence of pigment in the body i.e. It’s seen in all-white dogs and cats with blue eyes. These animals are unable to produce pigment of any kind in their body. Coat colour and the colour of the back of the eye are both caused by pigment-producing cells, known as “melanocytes”. If the genes to produce these cells are absent, a white coat and blue eyes are the consequence.
Hearing is made possible through a layer of specialised cells in the inner ear. These “hearing” cells originate from the same stem cells as pigment-producing cells. Therefore if an animal has no pigment in its body, it is likely that it will also be deficient in the specialised “hearing” cells, and it is likely to be deaf.
Some white animals have odd-coloured eyes (e.g. one blue, and one green), and often they will have hearing on the same side as the coloured eye, but deafness on the side of the blue eye.
Some white cats with blue eyes may have a smudge of dark grey fur on the top of their heads, almost like a dusting of soot. These cats clearly have some pigment cells, and are less likely to be completely deaf.
It is surprisingly difficult to assess hearing in a young animal. There are all sorts of tests that can be carried out: calling them, knocking on windows, blowing whistles or spraying aerosol cans. Unfortunately, even kittens and pups with normal hearing tend to ignore these things, and deaf animals can be very sensitive to vibrations, or they may have excellent eyesight that allows them to seem movement at the fringes of their vision.
There is a definitive test for hearing in animals, but it is not widely available. The so-called Brainstem Auditory Evoked Response (BAER) test involves connecting electrodes up to the skull, and measuring the electrical activity in the brain. With normal hearing, electrical spikes are seen when a sound is made beside the ear. This test provides a good, objective way of checking the hearing in one or both ears. Unfortunately, the test is not available in Ireland.
In most cases, if deafness is suspected, a vet will carry out simple observational tests: if an animal is deaf, their owner needs to be given careful instructions on how to make sure that their pet is safe throughout his life.
Up until now, if an animal was born deaf, nothing could be done to help its hearing. However, in the past decade, vets have implanted cochlear implants into dogs, which can restore hearing. At the cost of €20000 per ear, the cost is prohibitive.
So most people learn to adapt their pets’ lives to the lack of hearing. The most important aspect is safety: they cannot hear hazards, including cars and other animals, and they cannot hear their owner calling them. So in most cases, deaf cats cannot be allowed outside, and deaf dogs cannot be allowed off the leash.
It is possible to train dogs to respond to hand signals: google “training deaf dogs” to find out more.
On a related theme, I saw a piece online this week where a teenager has invented “wearable technology” gloves that have sensors that allow them to detect hand movements. He has written software which allows the movements made during sign language to be translated into verbal speech which can be played on a smart phone. This is not related to veterinary but it is fascinating, nonetheless. Perhaps one day similar technology will help us understand pet body language.
Questions from listeners
- My 3 year old Cavachon is licking her paws incessantly, particularly the front right. We’ve changed her diet to Royal Canin Hypo Allergenic, no more little “tit bits” and she’s been on a course of cortisone also but to no avail. What can we do?Kathryn
- We have a lab and a German shepherd who both live inside and have skin problems we give them steroids but is there anything else we can give them.
- Our two year old cat hasn’t been eating her usual amount for the past few days, the vet said she’s healthy otherwise – why might she be off her food? She’s nibbling, but not eating full meals.
- I recently bought a doghouse for my dog while me and my partner are at work. It was an expensive house but the dog won’t go into it ?. What do you recommend? James in Westmeath
- We have 18 month Lab X – it loses its ‘coat’ twice this last year – is it OK? Dog is very partial to legs of furniture – any simple ‘cures’ for this? Thanks – Richard Clondalkin.
- My 3 year old shih tzu cross,is quite well behave when out walking off the leash. But recently has started barking at other dogs as she runs in front of them as if in a controlling manner. What is this and can I stop it?
- Pat, my dog had fibromas removed before Xmas. Brought him back to get stitches out and it was so traumatic for him. We have found some stitches that weren’t removed. Do we need to bring him back or what will happen.
- I have a lab and a mutt. Just wondering if a walk on a lead is as good as a free run? Helen
- My 6 year old cat (who has no miaow) periodically holds down her left ear, and seems to clean it often. My vet checked it, and said everything looks fine, but I’m concerned still. It doesn’t seem to cause her pain yet as she is holding it down, I feel it could be?