Sludge? Help!

Rabbits Online Forum

Help Support Rabbits Online Forum:


New Member
Mar 5, 2021
Reaction score
Jamesburg, NJ
Hi everyone- I found this in my rabbit's cage yesterday afternoon. Is it urine sludge or a calcium deposit? Do I need to take him to the vet? It was only this small amount, the rest of his pee looked fine. Since then he peed a few times (sometimes only a small amount) but no more of this. He has also been acting normal (eating, drinking, playing, flopping, pooping, etc.)

We recently switched his pellets- he was on Oxbow adult rabbit food for most of his adult life, then switched to oxbow garden select for a short time, now back on oxbow adult rabbit food. The calcium content is between .35% and .75%. He eats spring mix lettuce a few times a week in a small amount but primarily eats romaine lettuce.

Any insight would be much appreciated. My little guy has been through a lot (liver lobe torsion surgery in January, stasis in June) so I am really praying this is something that will resolve itself without needing to bring him to the hospital again. Thanks!


  • 20220924_144723.jpg
    779.7 KB · Views: 0
Last edited:


Well-Known Member
Feb 23, 2020
Reaction score
I would say that if this is the first occasion then keep monitoring his peeing habits:
-Frequency, How long does he is doing his job, does he make any sound during peeing that would indicate that he is in pain or unconfortable, also check his legs whether they have any pee on it.

If any of the above or this peeing structure keeps up= vet visit.

And of course if any other serious stuff happens: not eating, unwell, blood etc...=vet

Also since I don't know what you know about Rabbits: Switching pellets is a "procedure" with Rabbits. You can't just change their pellets from one to a different one immediatley. A generic idea how you would do pellet change:
7 day procedure:
2 days 25% new pellets 75% old one
2 days 50% new pellets 50% old one
2 days 75% new pellets 25% old one
final day 100% new pellets

Then again if any belly problem happens during this time: stop feeding the new one. And of course if you are familiar with your Rabbits eating habbits this logic can be an extended one like 10 day or more if your Rabbit has a sensitive stomach.


Jenny - Health & Wellness Mod
Staff member
Sep 10, 2012
Reaction score
Utah, , USA
That does look like bladder sludge. Which will mean your rabbit will always be prone to it being a problem. As long as he's still eating and acting normal, I wouldn't think vet intervention is needed yet. I would work on diet changes and improving activity levels. For my bladder sludge prone buns, I had to reduce pellet amounts and feed low calcium veggies. And some rabbits may do better with no pellets, with just free fed good quality grass hay and low calcium veggies(and a salt lick). Also making sure your rabbit is drinking really well and staying well hydrated.

Making some changes to a rabbits environment can also be helpful. Having an environment where a rabbit routinely jumps up and down off of things, can help keep any sediment present in the bladder from settling, and keep it churned up so it's more easily expressed when the rabbit urinates(as you saw in your rabbits urine).

There are also urinary supplements that may prove helpful. I can't speak from experience using them, but the sherwood urinary supplement looks the best to me. I think it's the one I would try if I ever had a bladder sludge prone bun again.

But even though this is what I might do, if you have any doubts or concerns about your rabbits health, how your rabbit is doing, or if something is wrong, it's always best to consult with or contact your knowledgeable rabbit vet, immediately if necessary. With your rabbits preexisting medical issues, it may be a good idea to have him checked by your vet regardless, to have a urine test done to rule out a UTI and possibly xrays as well to make sure there is no sludge build up in the bladder. Certainly have it done if symptoms worsen.


Latest posts