When you say they got worse on septrin, do you mean the respiratory symptoms got worse? How bad is their breathing now? Has the vet checked for pneumonia and associated fluid in the lungs? If it is present have they considered prescribing a diuretic to get rid of the fluid and help ease their breathing?
I have to say that I too am becoming increasingly concerned at the amount, types and doses of different antibiotics (abx) that have given to these young piggies over the last 4 weeks. Aside from side effects for the pigs themselves this is a sure-fire way to select for antibiotic-resistant bugs. This is why my vets hardly ever prescribe antibiotics (even for a URI) until they have the results of a culture to identify both the bug concerned and its sensitivity or resistance to the various types of abx in use today. In the event of an emergency they will often now opt for doxycycline as a first choice, because we know for a fact (from cultures) that most of my piggies carry baytril and septrin resistant bugs. Baytril is however still a very effective abx, especially for younger piggies with URI's that have not had time to build up/be exposed to resistant bugs as will happen over the years..
Antibiotics should be given for a MINIMUM 7day course - no stopping and starting, and if the infection is a stubborn one the dose should be continued without a break for a further 7 days.We know antibiotics can affect guinea pig gut motility (which is normally already present because of the illness/reduced food intake) and supportive care, in the form of syringe feeding and gut motility meds, should be part and parcel of any treatment regime for a poorly pig. Gut motility issues should NOT of themselves be a reason to stop a course of antibiotics within the first 7 days unless there is an extreme reaction by the pig (which can occur in some cases) in which case the drug should be withdrawn in favour of an alternative.
Looking at the drugs they have been given so far and pickup on some points from earlier posts:
- Baytril is OK to give guinea pigs that are 12 weeks old. It has been reported to interfere with cartilage development in young rabbits and dogs.....which is why care is normally exercised on whether to prescribe to pregnant/lactating sows and their pups.. It is a bactericidal antibiotic - ie it kills the bugs outright. It has a broad spectrum and is the only licensed antibiotic for guinea pigs.
- Septrin contains two drugs one of which is bactericidal but the other is only bacteriostatic - ie it prevents the bugs multiplying further but doesn;t kill them outright. Like baytril it has a broad spectrum of activity and is normally second choice to baytril for guinea pigs but is unlicensed. If they got worse when just on septrin it is difficult to understand why athey are still being prescribed it.
- Tylosin is a very specialised bacteriostatic antibiotic that is normally used to treat mycoplasmas and is not very effective against bacteria.....however according to the 7th Edition (2007) of the British Small Animal Formulary
it specifically states Tylosin is not recommended to be given to guinea pigs.
It really does depend on how serious the respiratory symptoms are in your piggies at the moment and how long this latest phase of combined baytril/septrin administration has been going on for. in terms of what the next steps should be
1) I would certainly suggest talking to the vet on whether the tylosin should be withdrawn immediately because it is contraindicated in guinea pigs. (unless of course the most recent edition of the Small Animal Formulary has now cleared it for use with guinea pigs)
2) I would suggest that the next step forwards is to try and identify the bugs causing the problem by taking nasal/throat swabs and sending them away for culture.
Normally my vets would exepct to wait for two weeks before taking a sample in order for the abx to get out of their system in order for the culture to be meaningful,However in your case, that is not an option and, it would be hoped that the bugs causing the problem are still present in reasonable quantitiy given the continuing symptoms so can be cultured and identified despite the abx they are currently on.
3) If there has been no improvement (or even worsening) of the respiratory symptoms then an additional option (so you don;t have to wait for the culture results) is to try an alternative antibiotic
at an effective dose for a sufficient period of time. Doxycycline would be a MUCH SAFER alternative than tylosin to treat suspected mycoplasma and it is also a broad spectrum against other bacteria hence why my vets are more inclinced to use it s first response..
Marbocyl (similar to but stronger than baytril) could also be an option but given that baytri has not been effective at wiping out the bugs they may very well prove resistant to marbocyl as well as it comes from the same fmily of abx.
Finally there is azithromycin - this is used successfully for stubborn URI's and abcesses in piggies - but very few vets wish to prescribe it. It is not however effective against mycoplasmas.
4) Lastly I think it is absolutely essential that you continue to consult with one single vet of your choice - the most cavy savvy one - and not see any others in the practice to ensure continuity of care.
I am not a vet or veterinary nurse - but I am a microbiologist with PhD in infection and immunity and long term guinea pig owner who has worked with my own very cavy-savvy exotics vets over the years and treated many different types of infections in my own pigs - many of which were multi-drug resistant on culture. If your vets wish to talk to other vets about the alternative abx mentioned above, - then I suggest they be referred to Simon Maddock at Cat and Rabbit clinic Northampton on use of azithromycin and marbocyl......and Rob Reynolds/Celine La Rochais at Seers Croft in Horsham on use of doxycycline.
I am so sorry that what started as a not uncommon inconvenience in piggies bought from a certain chain of pet stores (but that should have been easily resolveable with an appropriate dose/selection of abx first time round) has turned into a complete nightmare for you, your piggies and your family. I admire and support your determination to get them the best treatment and hope the information above will help you achieve that.
Fingers and paws are all firmly crossed here in the Pebble household.
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