How can I get my dog to stop lunging and jumping at other animals?

I rescued a Black Lab didn't realize she was underweight till we went to the Vet 2 yrs later my little girl is close to 100 I weigh 118, get a picture of it, she does jut what yours does I got a gentle leader about 1 yr ago, she doesn't like it and sometimes as we're walking she throws herself on a lawn and runs with her head on the ground trying to get it off and she does, I slip it back on, it is wonderful they can bark, sniff, have a treat it work like a horses halter and there is no choking, I don't have to use it all the time now, I put it in my pocket and it she starts to take me airbourne I drag out the gentle and say ANNIE GENTLE LEADER!!! She looks back and comes back to a nice little trot and I don't even have to put it on her

All three - great answers. I have Pitbulls and my son also. I have walked 5 of them with pinch collars and I'm only 5'2", not very big or strong.That's about 290 Lbs. of dog. I always have complete control once the dogs get the idea. I've never tried the Gentle leader halties but a lot of people swear by them. See if a pet store will give you one or both for a trial period and see what works for you. Talk to someone who has classed, explain your problem. They may be willing to help you. Meanwhile try all the other things suggested.

There are two things that I think you could try.

The first thing that you could try is to make other dogs/animals a positive thing. Whenever he sees them, immediately start giving your dog an extremely tasty treat (such as a small piece of chicken) before he has a chance to start getting excited, lunging, or whining. You said that you could get him to sit when another dog is approaching. Do that, and then start handing out the treat to keep him focused on you. Make him realize that when he sees another dog/animal, he should turn to you and be rewarded. This should also take his focus off of the dog/animal.

The second thing that you could try is to turn him away and walk him in another direction as soon as he starts trying to lunge at something. If you have trouble handling him, I understand this may not be easy. I would suggest going to your petstore and checking to see if they have any collars, harnesses, or head collars that may give you better control. If you have a friend or family member that is willing to help and has a dog (that won't jump and get excited to encourage his behavior), you could try meeting them somewhere and practicing. Let your dog approach them and their dog, and as soon as he starts getting excited and starts jumping or whining, turn him around and walk in the other direction. Once he has the chance to calm down, try to approach a second time. As soon as he starts jumping and whining, turn him around and walk away. It may take a while for him to get the idea, but he should catch on.

You said that your dog has never instigated a fight. That is a good sign. However, if you start to feel that his behavior is aggressive, I would advise not using the methods I mentioned and getting a dog trainer to help you.

Good luck to you and your dog! I hope you find something that works for you!

Jessica, I completely agree with Nelson's advice. Some dogs do best with a pinch collar and if used correctly they are not cruel at all. I am currently working with a great trainer in the St. Louis area and we use a pinch collar. Nelson is correct when he says the collar mimics the mothers corrections and when an alpha dog is keeping the peace within the pack. I wouldn't try to train with a pinch collar without some instruction though. I would suggest getting into obedience classes now, don't wait until you gain some control over your pup, now is the time to get started.
If you want one-on-one training I highly recommend my trainer, Pat Patterson at the Delta 9 K9 Academy. Pat worked for the DEA and Illinois State Police for many years training tracking and drug sniffing dogs. He has great insight into dog behavior and can also help us humans to understand how dogs think. If you're interested in getting his number just leave a message back here on your post and I will make sure I get it for you.

Best of luck. And remember, an obedient dog is a happy dog.

Sounds like a real rambunctious dog that may need a pro, but I have some advice that may work in the interim. You may need "one on one" instead of a training class with other dogs if you decide to get a trainer.

Exercise before training is important and you should keep training treats with you first.

I would start with a pinch collar. Some people may disagree, but the pinch collar just mimics mom's gentle correction when the dog was a puppy. Likewise, the pinch collar mimics the correction that an Alpha male performs on adolescent males that get out of control. A quick tug will give your dog the message that you are in charge.

Next training: do not let your dog walk ahead of you. Keep the leash short and step in front of the dog as you walk (your back to the dog). You can practice this indoors in a narrow hallway or corridor, so he can't attempt to run in front. I use the command "back" and my little monsters know that I want them behind me. I continue stepping in front and when the dog continues the behavior, I block his way and stand quietly. It takes about a day and all of my foster dogs "get it" after a while. Some respond in minutes.

I find that when the dog knows that I am the front man, then all other training becomes easier. Weimararners are great dogs, but need to expel a lot of energy during their formative years.

Good luck. I am sure that you will get great advice from other zootooers, and you should do what is comfortable for you.