Please step in with syringe feed top up and watering as soon as your guinea pig is losing its appetite. Switch from weighing weekly to weighing daily at the same time to monitor the food intake; 80% of it is hay, which you cannot control. Your home care is as important as any medical care in getting a piggy through a rough patch.
Take the time to read our very detailed, step-by-step guide. We have included tips on what you can do with what you have at home or easily available from a pet shop, supermarket or pharmacy (mushed up pellets and 1 ml syringes without needles as well as probiotics and some extra vitamin C to help boost the immune system for 2-3 weeks).
Complete Syringe Feeding Guide
First Aid Kit For Guinea Pigs
URI is perfectly survivable if it is seen and treated promptly by a vet and if you keep your piggy going with syringe feed support while the going is rough. The need to breathe comes before the need to drink and only thirdly the need to eat. Antibiotics are additionally appetite killers as they impact on the gut bacteria as well as the respiratory bacteria, which is why the first few days can be quite a struggle until the meds kick in and the breathing is freer. It is the seeing a vet promptly, the not support feeding and watering that are often at the root of failure.
There are some other problems that can cause non-bacterial respiratory infections or pneumonia, which are much rarer but can often not be treated well (bordetellosis, transmitted by rabbits or dogs with kennel cough or pneumoccocal infections "atypical pneumonia" which usually hit out of the blue and which your piggy doesn't have, so please don't panic!)
If your guinea pig's upper airways are full of mucus, please ask your vet for a mucus-thinning product (UK: bisolvon powder). If the lungs are fluid filled, ask for a diuretic to help drain them. Easing the breathing as quickly as possible is vital for guinea pigs, as they are then more interested in food and can fight their illness much better.
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