TM is right and it is the other way round, rabbits can carry bordatella which is not a problem to them but fatal to the guinea pig.

To me as a guinea pig owner it is all well and good getting a companion for Julian but what about the pig being lonely? Guinea pigs are highly social and need company - so to be kind you must get 2 guinea pigs.

Rabbits can kill pigs with a kick, either outright or by causing fatal internal damage. I have unfortunately been at the vets when the result of such an incident came in - the pig was gurgling and suffocating because it had been kicked breaking some ribs and puncturing a lung. Needless to say that will haunt me forever and the pig was put down. The kick probably won't be on purpose but as the rabbit Binky's about or moves normally.

The diet is also a problem - guinea pigs cannot eat rabbit food, also they need a lot of fresh veg daily, the amounts which would give a rabbit diarrhoea.

I completely disagree with risking guinea pigs lives by keeping them with/letting them play with rabbits (one kick is all it takes). A rabbit cannot communicate with a pig like it can another rabbit (and vice versa).

I have been told by other rabbit keepers that there is a great debate over whether rabbits need company. Personally when you think wild rabbits live in colonies I think with enough space rabbits can only be happier in the company of another rabbit with which to do "rabbit things" with