last night while my guinea pig was eating his veggies & hay he was making this low almost farting kind of noise. I picked him up and put him close to my ear and it defiently sounds like his breathing is causing this noise. when listening carefully i also kind of heard a slight whistling noise. after he stopped eating he eventually stopped the noise. I have never heard him make this noise before. then today he seemed fine, he was just sleeping like usual so I went to clean his cage and gave him fresh hay and pellets. so he went to eat it and he started making the noise again. it doesn't happen 24/7 so I don't get how it's his breathing because he has to breath all the time lol. so I really don't know. but I am almost positive it's his breathing. it almost sounds like it happens mostly when he is eating. he is eating, drinking, and pooping normally. no difference in behaviour. He also is kind of over weight. I do try to limit his amount of pellets I give him, but he is chubby. the problem is that I cannot afford going to the vet right now. the only money I can put towards a vet at most would be 40 dollars and that most likely isn't even enough to just get the vet to see him. Please help me and tell me what you think. some things on the Internet are saying that it could possibly be a respiratory infection but I really don't know, he doesn't have any other symptoms of it from what I have witnessed. please help me, I am so worried