We brought our cats from Australia to US about 2 years ago. That time we organised everything through our local vet and everything went according to plan. They went from Gold Coast to BNE via car, BNE-SYD-LAX (QF) spent the night, then LAX-DEN-ATL (UA) the next day. Picked them up from UA Cargo, and they were happy to see us. (Should have signed them up for the AA Challenge. They could have made Plat with this trip!!)
Coming home in 6 months time will be a different story. From research, if we do the same thing through a local vet here, it will cost us a fortune.
If your got a handle on the AQIS importation stuff and all is in place with import permits , vaccinations, and bits, then your pretty much there with getting your felines home.
They do travel in an area of the cargo hold that is pressurized. They usually travel on a Air Waybill cargo manifest with handling instructions of 'Live Animals' So they know where to put them, in the cargo.
As long as they DON'T sedate them, they will be fine. DO NOT let any vet tell you its best to sedate them. If they are sedated they cannot regulate their body temperature and this will hurt them traveling. The other problem is the sedation will not last for the whole trip so they will wake up 1/2 way through and be more terrified of the situation rather than building up a tolerance.
Not sure how the Rabies thing works for Japan, but for me, the whole amount of quarantine in Australia, depends on the 150 / 180 day rule. For every day after 150 days from the test, means an extra day in quarantine in Australia.
All cats have at least 30 days quarantine in Australia. Not sure what extends this for cats from Japan.
As shillard suggested some airlines allow you to carry on small dogs and cats into the cabin, but for pet importation into Australia, they have to be manifested and go in the cargo hold.
That's about it for now. Good luck with it all.
Im a bit worried that my cats have developed a bit of an southern American drawl, and they will be made fun of, by the other cats in the neighborhood , when we return.
Anyway.....
Rob