here's my perspective.
A muzzle, is a tool, i have used them, and no stress on dog involved in wearing a muzzle if trained to wear one correctly.
You should be able to prevent the dog getting anywhere near enough to prevent a bite, with a leash.100%
Dude - you have a tiny light weight dog, not sure what the problem is with keep your dog off passers by?
So no need for a muzzle really. Unless you want to be able to day dream and not pay attention when out with dog. Which is not a great idea.
You could do two things at home. Muzzle train , by introducing it slowly and feeding the dog treats through the muzzle for quite a while before slowly putting it on. Then also have the dog on a leash near you, feeding them treats and using a clicker, (look up clicker training) until they are comfortable with the stranger. I'm sure there are you tube videos on both muzzle training and clicker training. It's a good idea to have the dog happy with a muzzle In case they need vet treatment sometime so they don't bite the vet.
I recommend any dog is muzzle trained, aggressive or not, and chihuahuas are no different. Just nevause they are small doesnt mean they should get away with behavior problems. I'm not sure if they make any for chihuahuas but basket type muzzles are best because they can still drink, eat, pant, etc.
Teaching "place" can be a big help when getting a dog calm in situations. Give them a bed or mat that us their "place" and lead them onto it, tell tem to lay down, and give the command place. At first mark and reward as soon as they lay down on their place, and then slowly add duration and eventually they will learn to be calm on their place indefinitely until you release them.
Your dog is misbehaving, there may be many reasons, some of them are given
lack of training.
lack of exercise.
lack of nutrition.
Boredom. (not having a partner dog or lonely for a long time in a day)
lack of sleep(rare)
These are the basic reasons why your dog misbehaves with you or your family members, friends & neighbors. A few years ago i also had this problem, my dog (named jimmy) used to bark at my neighbors and some of my friends. my dog was physically inactive. then I went to the nearest vet but the problem was not resolved, I also hired a pet trainer who charged me $70/day but nothing works. there was a time that I regret about having a dog at all. And then an old friend of mine discovered a course for dogs which I think it may work, but it was better than my expectation! my dog not only became well behaved he begin to follow my all commands like (“sit”,” run”,” come here jimmy”, etc). after months we together went for hiking and jimmy cooperated with me very well, it was an amazing trip.he became so well behaved, interactive & obedient that I never expected. I’m glad that I got jimmy now we are best friends.
If you can relate from this story and your dog isn’t well behaved then you should try this course (here is the link- http://bit.ly/2YMzFt9 ) I can assure you won’t regret
just copy and paste this link on your browser if it’s not working.
Have a nice evening with your fellow met.