Hello, I am Dr. B, a licensed veterinarian and I would like to help you with Bubbles.
I do apologize that your query has not been answered before now, but different experts with different expertise do come on at different times. I have just arrived online now, have read your question, and must say that I share your concern about Bubbles.
Now I am less concerned about the sleeping (since this is just a non-specific sign that he feels unwell) but I am very concerned about the lack of feces because you are correct that this could be a sign that he is starting with GI stasis or that there may be a GI obstruction leading to stasis. If he had the diet chance (once he was taken in) and was castrated three weeks ago, these may not be related. Still the fact remains that no matter the cause, if we have a rabbit who may have compromised GI function is a rabbit then we need to be very proactive with and get back on track asap. Especially since Gi stasis is one of the few true rabbit emergencies. So, if you think he is not producing feces, and/or eating less and drinking less, then it would be prudent for him to be seen by his vet before this can progress any further.
Just to note, some of the other signs we can see with gastric stasis:
Now in regards XXXXX XXXXX "why" he is lethargic, showing a decline in fecal production and possibly appetite and thirst can be a little trickier. There are of course a range of primary issues we must consider (ie Gi disease, dental disease, respiratory infections, etc), and this is something that a full physical exam by your vet will be able to shed light upon. The vet will be able to listen to his guts, check him temperature, and have a general evaluation of what underlying trigger might be ailing him.
Depending on the vet's findings, they can address the underlying trigger and initiate treatment. To keep the guts moving and get them back on track, often these cases need pain relief, pro-motility drugs, +/- antibiotics. If his signs are severe, he may need to be hospitalized. Or if you are able to provide diligent supportive care at home, they may advise you on how to syringe feed Bubbles.
Typically, rabbits in this situation need to be hand or syringe fed (usually hourly) to continue nutrition input to meet their body's requirement and keep his guts moving to prevent/address stasis. To support him, it is worth getting a vet to dispense a critical care feeds that you can syringe feed the bunny. A very good product for this is Oxbow’s Critical Care feed (http://www.oxbowanimalhealth.com/vets/products/critical_care) or Recovery Diet and most vets will be able to provide this to you. This is a highly nutritious herbivore feed that can be easily made into a slurry for syringe feeding. And it is much easier to use then trying to create a balanced critical care diet at home.
Now be warned that if you do undertake syringe feeding him, then this can be a challenge (we all end up with rabbit food on us when we are syringe feeding rabbits). To administer it in as stress free means as possible, I would advise having a peek of this guide (HERE) since a video is worth at least a thousand words. If he is quite resistant to being fed, then do watch the end of the video for 'towel wrapping' him to keep him snug and secure while you are feeding him.
In regards XXXXX XXXXX if he is severely dehydrated then the vet might give sterile fluids under his skin. Otherwise, you can try tempting him with pedialyte (fruity flavors are best tolerated), Lectaid (the vet can dispense this) or diluted Gatorade (50% diluted with water) in a pinch. These will help replenish electrolytes and get some glucose into his system. If he isn't keen on it, you can give pedialyte via dropper of syringe. A typical dose for animals is 4.8mls per 100 grams of body weight per day (obviously divided over all day drinking). This is his maintenance rate and it is a good starting place for supporting him against dehydration.
Overall, lack of feces is a very serious situation for a rabbit and this needs to be addressed immediately. Therefore, I would advise that he should see his vet immediately. They will be able to treat him for this and advise you on how to administer critical care diet and nurse him through this situation. Overall, prompt treatment and supportive care are the best things we can do to get this under control and give this little one the best chance of recovery and getting back to himself.
If you don’t already have a rabbit vet, and wish to find one near you, by checking here (http://www.rabbit.org/vets/vets.html).
I hope this information is helpful.
If you need any additional information, do not hesitate to ask!
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