How much kale should I be feeding my rabbit. He is a 3.5 pound dutch. I've heard it is high in calcium...
You'll hear a lot about kale being high in calcium, spinach high in oxalates, and so on. Kale
is high in calcium, relative to some other green vegetables - but it's important to realize that it isa relative thing. If you look at the tables for percentages of various substances in vegetables, they'll vary - but remember that those tables are for dry weights. Green vegetables are mostly water, so the actual amount of calcium in kale, while higher than in, say, lettuce, still isn't a huge amount in absolute terms.
I discussed this with the vets at Cornell when I had my first rabbit, Scone MacBunny, in the Exotics Clinic for a bout of stasis years ago. They said if he likes kale it was perfectly OK to feed him kale, and in fact that's what they used to entice him into eating again once he'd been rehydrated. It was only late in his life that they had me cut out the kale, because Scone had started having problems passing off the calcium in his urine as he did as a younger bun.
Unless your vet advises you otherwise, or the rabbit develops kidney stones, I wouldn't worry about eating reasonable amounts of kale as part of a mixed diet.