I thought that you feed pellets to the size of one ear, greens to the size of their heads and hay to the size of their bodies as a rough guide?
Here is the problem with spinach. The oxalic acid will bind Calcium/Magnesium/other minerals together, thus will make them insoluble. Therefore, it reduces the possibility of using them in the bone structure. The calcium content might get stuck in the bladder and cause bladder stones.
Spinach is a big source of beta-carotene (provitamin A) which is so important for body development. It also provides a high content of other vitamins (C, E, K etc) and minerals (Calcium, Iron, Magnesium, Folic Acid, Potassium etc) which are required for a healthy rabbit. However, besides these beneficial elements, spinach also contains oxalates, unhealthy in significant quantities.
Oxalates are not poisonous substances like pesticides or toxic plants (eggplants, potatoes, and tomato plants). Oxalates are naturally-occurring food toxins (organic acids) that can hinder your rabbit’s urinal tract, and produce itchiness in the skin or mouth if eaten in greater quantities. Still, you should definitely not avoid it when feeding your house rabbit. The good, the spinach offers, is greater than the bad, though.
So, if your rabbit eats spinach regularly, oxalates can become toxic.
roughly rabbits should have greens in a ball size of their head and hay completely unlimited (but it is said they'll eat their body size a day, I think its much more tho?). pellet is debatable but the general advise is a tablespoon per KG of body weight.
buuuuut some greens you shouldn't feed a lot of, and ideally the greens you give them should be mixed rather than just one specific type. spinach is high in oxalates as J&B said, so its suggested to feed minimally:
from https://rabbits.life/can-rabbits-eat-spinach/ - and many other sources quote the same, so its best to err on the side of caution. Kale is another that has the same issue of spinach.
but really the majority of herbs/greens you feed a rabbit have limitations. I think the safest is basil & possibly mint as it seems to have limited issues. coriander (high in calcium), dill (same as above), rosemary (can cause bloating in large amounts) etc. its why its vital for a rabbit to have a varied diet in terms of greens, feed too much of one and you're asking for trouble. herbs are the safest usually, with limited sugar and water content (in comparison to carrot or, lettuce for instance). most recommend to feed 3-5 types of greens per week and mix it up, spinach is one of those that should only be fed once or twice a week ideally.
in answer to OP, probably not a lot of spinach can be fed in all honesty as it could cause further issues. I hope he picks up soon
Oh poor Dex. Is he eating hay?
I don't know about quantities but have read to feed "sparingly" as its high in oxalates. I hope you can get something else to tempt him
I agree with this .Can you pick him a handful of grass each day, surely he won't turn his nose up at that. I have always fed Spring Greens with no problems.
roughly rabbits should have greens in a ball size of their head and hay completely unlimited (but it is said they'll eat their body size a day, I think its much more tho?). pellet is debatable but the general advise is a tablespoon per KG of body weight.
buuuuut some greens you shouldn't feed a lot of, and ideally the greens you give them should be mixed rather than just one specific type. spinach is high in oxalates as J&B said, so its suggested to feed minimally:
Thank you