I'm sure I've written somewhere (but I can't find it) about my son's dog who was terrified/terrorized by the mere thought of having her nails clipped, due to a bad experience. She was so vicious due to fear that we couldn't get any vet to clip her nails without being anesthesized. Long story short....I spent about 4-5 days desensatizing her to the point where I could do a little token trimming and just gradually progressed to where she was completely okay with it. And then we moved onto a Dremel, which was a piece of cake. She really prefers the Dremel. But that must be studied thoroughly before you do that because it can be very dangerous.
That said, basically....break things down as many times as you can into as many smaller steps as you can make. In other words, you might sit on the couch with him and a bowl of ice cream and show him the clippers. Feed a spoonful. When he is comfortable seeing the clippers, stroke his feet and nails with your finger or hand. Feed a spoonful of ice cream. (or other highly tasty treat) Hold hands while you watch the movie. LOL.
Next day, do the same as you did before, only add in one more little baby step. Stroke his nail with the clippers. Feed. Praise. Do a little and stop while the goings good, while he's happy. Don't do more.
Next day, do all that which you did before, but now add a few more nails to stroke and maybe tap with the clippers. DO NOT CLIP YET. Make a big fuss...have a party, give wonderful treats for small progresses.
When and IF he's comfortable with the previous steps, try shaving off or clipping off the tiniest smiggen of a nail....JUST ONE NAIL. Reward and call it a day.
You get the idea. Baby steps. Reward for small successes and take your time. If the dog walks away, let him. Don't use force of any kind. If he wants ice cream or steak, he'll come back and let you do a little something in exchange. Slowly up the ante.
Make sure the clippers are sharp.
Something I wrote for someone else, but its on the Dremel.
Plan on taking a week or so to condition your pup to the Dremel. Clicker training is very helpful for this, but if you aren't using a clicker, you can still use the concepts. Here's what I did...or an aproximation of it:
Day 1...several times a day, lay the Dremel on the floor. Don't turn it on. If the dog so much as looks at it, say, "yessssss" and give a treat. Use tiny, tiny tid bits of hot dog or string cheese...something really yummy. Repeat if he looks at it again. Then don't treat for that. Wait. See if he'll take a step closer. "yessssss" and treat.
Day 2....Repeat day one and build on it. Once the dog is getting closer to it regularly, stop rewarding for that and wait. Wait until he sniffs it. "Yessss!" Treat and make a fuss.
Day 3...
Hold your dog in your lap on the floor and hold the Dremel in one hand....not turned on. "Yessssss" and treat/affection. See if you can touch his nail with it not turned on. Make a fuss and treat. Do this for just a minute or two several times during the day.
Day 4...
Then turn it on while holding it in your hand. "yessss" and treat/fuss over him if he comes close to investigate. Don't try to do anything overt to him with it. Just sit and hold it while it's running. Build on that. See if he'll come closer and sit in your lap while you're sitting on the floor. If not, turn it off and see if he'll get on your lap. Treat. Turn it on low speed so it's not too loud. "Yessss" and Treat, treat, treat and praise. If he's not too worried, you can try one light brush against the tip of one nail. Treat/praise. Try one more if he's fine with it and call it a day. Don't push it. You want to end when he's had a positive experience and not gamble that one more nail might be too much for him.
Day 5...
Repeat what you did on day 4 for a few sessions and depending on his acceptance of it, move forward a little bit. Do a couple of nails or a whole paw. Do another paw the next day. Never use any force or let the dog become frightened of it. You may have to go more gradually since you've already tried it but went a little too fast. You'll need to convince the dogs that it's worth it to get nails done.
My male Chihuahua doesn't exactly love getting his nails done, but goes along with it. He does however, guard the Dremel and will curl his lip and give off a little growl if another dog so much as walks past it when it's just sitting on a low table or floor. He's associated it so strongly with a party and high, high value treats, which with this dog is an obsession in itself.
Remember not to apply pressure with it and to do little, quick brushing-like sweeps...just 3 or 4 and move onto the next nail. You can come back to the first nail after you've finished the others on that paw. Too long or pressure can burn the heck out of them. If puppy has any pain associated with this, it can sabotage all your training efforts. You probably already know this. I presume you found out when you got the Dremel, but I thought I'd throw that in anyway.
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