I have two Irish Wolfhounds. The breed is very prone to bloating. I have had in the past three of my dogs bloat. A couple of them repeatedly. (Once they have, it's easier for them to again)

Causes:

Predisposition
Activity directly an hour or so before or after eating
Age
Stress
Anxiety
Pain

What to look for.

Panting (pain)
Won't lay down
Restless
Distended Stomach (looks like they are pregnant)
Hard Stomach (feels like a basketball)
Abnormal water intake (tanking up)

What is happening?

Stomach is basically blocked. Food, water, air is trapped and will not pass. Bloat is early form of torse. If untreated the stomach will torse, or "flip over." Twisting the stomach shut at both ends. Torse will kill the tissues (no blood). It is a painful way, if untreated, to die. Bloat (savable) Torse (lethal)

What I do.

I feed my dogs about an hour after their exercise. After they eat I watch their water intake, and limit the availability. (I let them get a drink but don't leave the bowl down) I will let them out to potty, but not leave them out to play until an hour has passed. Infant Gas Relief is what my vet and breeder have told us to use. It is sold pretty much at any drug store/wal-mart. It's a liquid that comes with a dropper. If given at the onset or early stages it can stop the bloat. I take it with me on walks, romps in the pasture, and traffic stops (my name for long walks downtown because traffic will stop and gawk at my dogs) If I even suspect a problem I give them a full dropper. (Vet told me that they cannot overdose) when we get back to the house or truck they then get about 5-15 cc's of milk of magnesia. (calms the stomach and helps with discomfort)

Tubing

The "tube" is just a 3/4 to 1 1/2 polyvinyl tube. Stretch the tube from the mouth to the midpoint of the stomach following the esophagus. mark with a piece of tape. On my dogs it is about 2 and 1/2 to 3 feet. Take a half roll of tape (or any hollow thing that can hold up to a dog bite) and put in the mouth (so the dog's mouth is stuck open with a hole in the middle) and tape the jaws closed with vet wrap. Spread a dollop of lube on the tip, and feed the tube down their throat to the tape mark, be careful not to go into their windpipe. If you can't get it down or run into resistance, do not force it. (you can poke a hole in the stomach) the idea is to empty out the stomach (the food, water, and air) Suction on the tube, while moving it around a little bit. pump the stomach and remove the balloon-like pressure. Pull out the tube, take out the tape and apologize.

What the Vet can do:

Administer pain meds. Staple the stomach to the abdominal walls (stapling or suturing done during surgery, preventing the possibility of torse, but bloat can still occur) Has the knowledge and experience. Take radiographs and find out if your dog has torsed.

READ THIS:

Talk this over with your vet. I know this only from my experience. It might be different with your dogs. It is best done by a professional. I went through this three times before the vet showed me what to do. I would only attempt this if I could not get a vet, or had no choice.