Deaf dogs kind of come in three types (I'm not being sarcastic -- I'm being serious here).
1. Like Peter, an 'albino' dog (all white) is typically born deaf. All dogs are born deaf (yep, it's true) -- just like they are born blind (which is why the eyes don't open for a couple of weeks). It is the color pigment cells in the ears that help the neural transmitters for hearing mature -- and if the dog is all white (or predominantly white) on one or both sides of the head the ear on that side of the head may never develop hearing.
A dog that is born deaf has no frame of reference for words. So you have to train them with signs and you take advantage of that inate dog thing that 'notices' and picks up on dog body language as communication (ears, eyes, tail, body tension, etc.) -- and you build on that.
THEY DO BETTER WITH OTHER DOGS. They realize they are different -- truly they do. And another dog will often become their 'ears'. BUT if you train them, they excel at anything scent oriented. It can be difficult to tell when a dog IS deaf because they become so adept at reading scent -- you may walk into a room and they'll turn to you simply because they SMELLED you coming. A squeaky toy may absorb them simply because they sense the puffs of air when it squeaks - not that they 'hear' it.
However -- breed groups have been slow to embrace placement of such dogs because they DO startle easily and can wake "on guard" expecting danger. So you have to be VERY careful about **how** you wake them up so they don't get scared.
Because I've read so extensively on deaf dogs I know all this, and because I've had the other two types I understand it. I've not a lot of perosnal experience with dogs *born* deaf. But I wouldn't be afraid of one ... not in the slightest. But it's a LOT of socialization and a TON of training.
2. An animal who is elderly and has "lost" its hearing -- this dog has a frame of reference with sound -- it's a sense they "Lost" rather than a sense they never had. So it's far more difficult for them in a way.
I always teach ALL my dogs some sign as well as all verbal cues-- from the instant they enter my house. It's far easier when they age and go deaf (OR blind).
I'm going to say that an aged dog that loses a sense can be more fearful and it takes training to counter that. The tips and tricks I'll type at the end of this are helpful for all dogs, but I think the aged dog needs the most support emotionally -- they can LEARN to function with out that sense -- but you have to teach them and show them that you'll help them replace that sense with other "input".
3. The third category is one most folks don't think of -- a dog who becomes "suddenly" deaf -- thru an accident or surgery. We had a cocker who had 'bad' ears his whole life with us but because of a series of bad vets, horrible allergies and an undiagnosed deep bacterial infection ultimately after we'd had him 3 years (and he was 5 then) he had to have bi-lateral ear ablations on both ears which literally removes the entire ear (inner, middle and outer) leaving just the ear 'flap' -- he looked like he was from FAO Schwartz -- lift up the flap of his ear and nothing 'there'. Just skin.
But it was fun -- I'd do it again in a heartbeat. Because he had a frame of reference for language and 'words' -- once he acclimated he LOVED sign. He learned about 75 human sign language signs. He lip read (oh yeah he sure did!!). And ... if he didn't particularly WANT to do what you were telling him to do, he was particularly adept at looking at the ceiling and finding it extremely *interesting* ("Hmmm, I'm a poor little deaf dog and I think she's talking to me but gosh, I can't HEAR her ... nice ceiling ... wow ... nice clouds ... hope she's done soon cos I really don't WANT to 'come' now!!";)
He was smart, he was the BEST therapy dog ever ... LOVED deaf kids (cos they knew his 'language';), and well, it was one cocker who loved kids ... period.
AFTER the ear removal he became insatiable -- he wanted to know 'the sign' for EVERYTHING. It was cute -- he took an almost perverse delight in knowing something the other dogs didn't know. Like the ASL (American sign language) sign for "dinner" is the same as "food" or "supper" or "eat". So when I'd call them for breakfast or dinner and I'd use the 'words' "Come Eat!" I'd use the sign for "come + food"
But then when David and I would go out to dinner at a restaurant, when I put them in their crates I'd tell them we'd be back, just going out for dinner -- which became the signs for "back + soon
and "mom+dad + go + food".
Yep -- nailed!! He'd look at me like "Hmmmm, soooooooooo Mom -- is there going to be a white box in OUR future??? Leftovers????" And the others hadn't figured out "going out to dinner" was necessarily the same as them eating.
TIPS and TRICKS:
Scents -- I would work with ANY deaf dog on scents (and "tracking" is ideal for them). But you can use essential oils to a great advantage with them -- an aged dog who has always loved to chase a ball but who is too blind to 'see' or can't hear it 'drop'? Put a drop of peppermint oil on HIS toys ... and he can find it when you toss it.
You wake up a deaf dog more by scent than touch ... waving you hand gently on front of their face so they catch your scent can help and you touch them gently petting them to wake them up rather than anything sudden.
Touch and vibration -- you can easily train a deaf dog to 'come' from several rooms away by tapping a broomstick on the floor and teaching him to 'come' that way. You have to be consistent -- a certain number of taps or a certain specific 'cadence' can develop meaning (kind of like Morse code in a way)
They can learn to know you are coming (and WHO is coming) simply by the feeling of their steps via vibration.
Companionship -- deaf dogs pretty much always do 'better' with other dogs. They can develop quite a complicated give/take from each other. Muffin relied on Foxy to really 'hear' something BUT Foxy (and **all** the dogs in my house) always deferred to Muffin as the 'watch dog' -- why? Because the 'deaf dog' had such an incredibly well-developed sense of smell that he was NEVER EVER wrong.
One day he was in the living room and suddenly barked and ran to the bedroom. He came back to the living room and 'got' us -- there was something we needed to KNOW in the bedroom. It was night -- he got us to the bedroom and barked one loud WOOF at the window.
So my husband went out with a flashlight to 'find' the intruder -- found nothing. But Muffin was still in a "sit" staring intently at the window. After David made sure there was nothing awful out there (and Muffin wasn't acting like "intruder alert" -- it was quite puzzling -- it was as if he was just TELLING US something he thot we'd want to know?? hmmm) -- finally we turned on the lights and ....
RIGHT IN THE CENTER OF THE WINDOW ... was a *tree frog*!!!
He sure as heck didn't 'hear' it -- but he DID smell it apparently. He knew it wasn't 'dangerous' -- but thot we oughta know apparently. But it truly drove home to us how incredibly sensitive their noses can be.
With a deaf dog you always train to build their confidence and to build that communication link between you and the dog and between that dog and the other dogs in the home. You really have to remember they 'think' a bit differently ... and if it's a dog deaf since birth, you have to remember they don't understand 'words' at all. It's all verbal cues.
You also have to remember A LOT -- particularly when out in public -- that other dogs won't know *your* dog can't hear. So that low rumble of warning a dog might give to 'warn' another dog? YOUR dog won't hear that and is at risk.
A deaf dog is NEVER EVER **not even once** off leash in unknown unsecured area. They can't hear traffic. They can't hear a predator ... and they can't hear you.
This isn't meant to discourage you ... not at all. I'd do another deaf dog in a heartbeat. I'd do a deaf-from-birth dog too -- it's just never happened for us yet.