I sailed with my family and two large dogs in 2003 and 2004. Like you, we were just not willing to leave them home. I also sailed for two years from 1990 to 1992, first singlehanded with a Springer spaniel and then with my new bride and her English setter. The dogs from the first trip are gone but we still have great memories.
My wife did all of the research related to traveling with our dogs for this recent trip but I can give you some of the key points and see about having her respond as well.
First, we applied for and received what I will call "British Passports" for our dogs. The process to get these passports is tough. As I recall, the rabies test took 30 days, not continuous, but two separate exams and samples run through a facility in Ohio. At that time, this was the only place in the U.S. that could evaluate and verify the test results.
These results are sent to Vet to sign off and then State department of Agriculture must sign off. Finally, the Ddg needs to get computer chip in neck.
I hope that I have provided enough information for you to track down the method of registering your dogs for a British Passport. I did a google search and came up with this link: http://www.defra.gov.uk/animalh/quar...ion/eu_reg.htm
I am sure that a little work will provide you with a good understanding of the British or EU passport requirements and benefits for animals.
Having this paperwork allowed us to enter islands otherwise off limits to dogs. i understand that things change but here is one example of the value we got from having this passport. In 1991 we tried to get our dogs into St. Lucia. I went as far as trying to visit the house of the Vet who was in a position to approve or decline entry. He was intransigent and threatened to send us out of the country. We were told by the security guard at the marina, who came to like our dogs, that the Vet planned to incarcerate our dogs and possibly put them down. Whether true or not, we never found out - we left before dawn.
In our second trip, we presented our dogs' credentials upon checking in with customs and immigration. The government vet, a young and very friendly guy, was at our boat within the hour, signed the paperwork and said that we could travel anywhere in St. Lucia with our dogs.
So, maybe St. Lucia became less restrictive over the years. I think the passport, which was effective throughout the Bahamas and Caribbean, made the difference.
With regard to exercise, our dogs swam constantly and we took them to shore every day and night for walks and play. Although we did sail offshore, the majority of our sailing allowed for this daily routine.
Our method of training the dogs to go on deck, when offshore, is to give them a command to go from the time they are puppies. From the first day we have a puppy, throughout their entire life, when they begin to go, we say, "go to it." When offshore, the same command prompts the right reaction.
Finally, there are certain dogs not allowed on this list, so you'll need to check to see that your dogs qualify. Certain countries also do not allow certain breeds, so you will need to do some research on this topic as well.
Good luck and happy sailing.