He sounds fine to me. Like I said hay and grass should make up 90% of his diet. I wouldn't give him cucumber or any other watery veg it can cause the runs. I give my 2kg rabbit a handful of pellets at night and the netherland dwarf gets half of that so depending on your hand size and the size of your dwarf a handful may be too much with the hay and veg diet. For an idea of veg I give mine a handful of mixed leaf stuff like spring greens, spinach and kale, I give carrot as a treat more than a main veg as its very high in sugar. As a rough guide I'd say unlimited supply of hay and/or grass, decent amount of veg (not too much to give him the runs but say a handful a day, introduce any new veg slowly), about an egg cup full of pellets in the evening for a dwarf but it does depend on his size, do you know his weight? At the top of this section theres a thread with a list of plants and foods that are safe and unsafe for rabbits, its worth having a read so you know what to give.

As long as he's pooing and peeing normally I wouldn't worry, you may find that with more veg he will drink less, again don't worry too much as it just means he's getting water from the veg.

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