Hi!
Please step in with feeding support if necessary. They have obviously not eaten much yesterday. Keep in mind that around 80% of the daily food intake should be hay, which you cannot measure by eye.
Whether that is caused by the cystitis (which can be bacterial or sterile, i.e. not reacting to antibiotics), the stress of the vet trip, the sedation or most likely a combination thereof is impossible to say. Please switch from the normal life long once weekly weigh-in to weighing daily at the same time in the feeding cycle (the weight swings around 30-40g over the course of 24 hours) in order to monitor the food intake and to be able to support feed as needed to the degree it is needed.
Weight - Monitoring and Management
Emergency, Crisis and Bridging Care until a Vet Appointment
Complete Syringe Feeding Guide
I would also strongly recommend that you start support with glucosamine, which is crucial especially if you are dealing with a sterile interstitial (i.e. non-bacterial recurring) cystitis. Bacterial cystitis is more common in the wake of the irritation/scratching of the bladder walls by stones or sludge. In sterile IC it is very much the natural glucosamine coating of the walls of the urinary tract that is affected; the coating prevents the corrosive urine from coming into contact with raw tissue. Since glucosamine is not classed as a medication but as a food supplement and since sterile IC is not well known outside vet circles that see a lot of piggies, it is usually not prescribed by vets even though it is the most effective treatment for a sterile cystitis, which has become a lot more common over the last decade.
We recommend to use glucosamine based cat bladder supplement capsules (like UK brand Feliway cat cystease; cats are the other species prone to urinary tract problems and also to feline sterile cystitis, FSC) because dosage and application is easiest with them. Simply mix the contents of 1 capsule with 2 ml of water until fully absorbed and either give 1 ml twice daily or 2 ml once daily per piggy. Always shale well before use to ensure that the glucosamine poeder is well distributed in the solution.
The effect is not instant as it takes time to build up but it really contributes to the long term comfort since in the case of a sterile cystitis you are looking at management especially of the recurring flare ups and not at a one healing treatment (there isn't any) until the cystitis is going away on its own - more in a matter of years than months. The metacam is also used in treating IC, especially the flares.
It is good that your vets have been able to close out the stones angle as urinary tract problems present with rather similar symptoms. That is a big worry off. Please conduct the full course of antibiotics and see whether that does the trick. If your piggies continue to deteriorate or if the cystitis is coming back as soon as the antibiotic has worn off, you are likely dealing with a sterile IC. Please contact the vet. IC can usually only be diagnosed by default. Continue with feeding support as much as is need to stabilise the weight. Cystitis can be very painful and antibiotics can also impact on the gut microbiome and therefore on the appetite in some cases.
