UPDATED: Reactive or Agressive dogs in Beginner Agility!

I think it would be a good idea to ask the instructor if those dogs could be muzzled.  The instructor has a responsibility for the safety of the dogs and owners in that class.

Are they "aggressive" or just demonstrative? My dog seems feirce at the end of a leash, but given the chance, she just wants to herd other dogs, not attack them. Can you talk to the other owner and find out? Tell them, and the trainer, that you are uncomfortable about this and it's interfering with your enjoyment of the class. Work together on a solution!

If you can't do that, and the situation feels unsafe, drop the class and ask for your money back.

Growling, barking and snapping at other dogs that is what the Blue Merle one does to all the dogs.  From what I have seen with interactions that it doesn't matter whether leashed or not..they took him out of the vehicle without a leash and he was acting agressive and they had to grab him.

We have a young aussie in my obedience class that acts the same way.  Being a really adept herder, she's just super sensitive to any sort of motion.  Since she is young, she's a little fearful.  The movement gets her all worked up, and her fearfulness then manifests itself as "aggression".  She barks, lunges, and growls at all the other dogs.  It's been four weeks and she's made huge improvements.  We've also got a corgi that does it too, and he's also gotten way better.  If your instructor doesn't really know how to handle these kinds of dogs or doesn't seem comfortable with them, it's probably not going to get better on it's own or even with a muzzle.  The muzzle will protect other dogs, but the aussie won't really learn anything.  If instructor just seems to be avoiding the problem, it would probably be best that the dog get some obedience and socialization training before doing a group agility class.

Well, the instructor has the agressive dogs kept far away from each other.   My other question is how to protect my dog if one should get loose?

Here are some ideas:

Pick your dog up.
Carry a spray bottle to spray it.
Lean towards the oncoming dog, look at it sternly, point at it, and firmly declare "no!"

Oh, if it's really food motivated, thow treats to distract it!

ORIGINAL: Liesje

We have a young aussie in my obedience class that acts the same way.  Being a really adept herder, she's just super sensitive to any sort of motion.  Since she is young, she's a little fearful.  The movement gets her all worked up, and her fearfulness then manifests itself as "aggression".  She barks, lunges, and growls at all the other dogs.  It's been four weeks and she's made huge improvements.  We've also got a corgi that does it too, and he's also gotten way better.  If your instructor doesn't really know how to handle these kinds of dogs or doesn't seem comfortable with them, it's probably not going to get better on it's own or even with a muzzle.  The muzzle will protect other dogs, but the aussie won't really learn anything.  If instructor just seems to be avoiding the problem, it would probably be best that the dog get some obedience and socialization training before doing a group agility class.

Great post and right on the money.  

ORIGINAL: Firestorm

Well, the instructor has the agressive dogs kept far away from each other.   My other question is how to protect my dog if one should get loose?

If they are only "reactive", nothing is likely to happen if they get loose, except a lot of butt sniffing and maybe some posturing.  Talk to your instructor about your fear and get some advice - picking your dog up may not be the best idea.  Also, "no" means nothing to most dogs (sometimes, it's better to say "sit" LOL - at least most dogs understand that word), although a body block may do fine with some Aussies - others will be so quick they can easily skirt you (and most of the dogs alive, except BC's) to get to what they want.  You can carry Direct Stop, or a small squirt gun, but it might be better, before jumping the gun, to ask your instructor if he/she knows the how the dog behaves off leash, and if you should be concerned.  Example: my dog can look pretty scary if someone meets her on leash and gets right in her face.  She may grrr, or even air snap to get them to back off.  But, she does not puncture other dogs, can be easily called off with "leave it" "come", and is generally obedient to a human asking her to sit or lie down.
Throwing treats only works if no other dogs in the area are off leash - otherwise you may cause a fight, and guess whose dog is closest to that action - yup, yours. 

This woman did say leave it and the dog didn't listen while on leash.  I highly doubt he even went through beginner obedience.  From what I have seen between dog and owner the dog lacks basic obedience and it appears that the dog is alpha.
 
I was really hoping that those who did get into agility class would have well socialized dogs.
I have a very friendly well socialized dog.  If Harley feels uncomfortable with the dog he is sniffing he just walks away no agression at all has ever been offered.  I actually have a well mannered little dog instead of a Napolean.
I will talk to the instructor before the next class.

ORIGINAL: Firestorm
I will talk to the instructor before the next class.

Sounds like a good plan! []

Some good points being made.

I am hearing of out of control and/or aggressive behavior occurring far too often with agility dogs. []

I think part of this is due to these being trained through mostly clicker methods with little or no balance in other aspects of their training outside of the clicker and more "positive only" techniques.

Many of these dogs could probably also use some basic social skills through leadership principles in addition to their training programs.

The agility arena is also an anticapatory, drivey, excitement filled situation where the dogs are already pretty keyed up to begin with, IMO.

This woman did say leave it and the dog didn't listen while on leash. I highly doubt he even went through beginner obedience. From what I have seen between dog and owner the dog lacks basic obedience and it appears that the dog is alpha.

First of all, no dog should be in basic agility without having gone through basic obedience, but that does not imply that the dog ever actually learned a "leave it" command, nor does it imply that he is either aggressive or "alpha".  BTW, truly dominant dogs are rarely either loud or lunging.  It's the dogs that are highly aroused, excited, or scared to death that are usually lunging at the end of the leash.  The likelihood is far greater that he is one of those.  Aussies are generally not dog aggressive, though there are certainly exceptions, but they do not like dogs to get right up in their face, and many of them will warn the other dog away with a few well placed air snaps and a show of their "mean teeth".  As herders, they are not alone in this behavior, which is common to other breeds, such as Shelties, Corgis and Cattle Dogs.  My Aussie and my Aussie mix regularly tell new dogs how they must approach (with healthy respect LOL), but neither of them have never bitten a another dog at play group.

I think part of this is due to these being trained through mostly clicker methods with little or no balance in other aspects of their training outside of the clicker and more "positive only" techniques.

And, on what science do you base that????  My own experience tells me that you are way off base.  These are just a couple of examples of positive training in action.  Both of these instructors run classes in which my students participate successfully, and the dogs they train include Keeshond, Malamute mix, Shih Tzu, etc., so not even all herders.  See their dogs in action - positively!
http://www.ledgehill-labs.com/Agility.htm
http://www.fit-n-trimdogagility.com/gpage4.html

ORIGINAL: Firestorm

This woman did say leave it and the dog didn't listen while on leash.  I highly doubt he even went through beginner obedience.  From what I have seen between dog and owner the dog lacks basic obedience and it appears that the dog is alpha.

I was really hoping that those who did get into agility class would have well socialized dogs.
I have a very friendly well socialized dog.  If Harley feels uncomfortable with the dog he is sniffing he just walks away no agression at all has ever been offered.  I actually have a well mannered little dog instead of a Napolean.
I will talk to the instructor before the next class.

Aggression is overkilled. In my view, there is no thing as aggression. Reactiveness, fear, guarding, what ever it may be. It sounds like the dogs may be a bit under socialized, making the aussies AFRAID of the other dogs.

And, my border collie's worst correction she's ever gotten was a spray in the face with a squirt bottle when she was killing the cat since she didn't have her collar on and no other way to stop her hyper focusing. Other than that, she's never had a correction, except for a "no" or deep "AHHT". And she's an angel. She lover (most) people and (most) dogs, except for our trainer and a lab in our class, whose a trainer and doesn't know crap.  I think it's unfair to make assumptions.