If your bun is suffering from a physical blockage, don't feed him w/ anything water or food. You need to get your bun to a real rabbit specialist vet, and a surgery would need to be done to remove the blockage of the intestine or perhaps the tube method will work on sucking the gas out.
Look around at your house, is your bun chewing on the furniture or the carpet?
Is there any bloat? if his stomach is suffering from bloat, then you need your vet to use the tube idea to suck the gas out first
Or if it is just a little bit of gas, you can get 2 ml of infacol every few hour just as a pre-caution.
If there is no bloat, and if your bun hasn't eat for more than 12 hr., then force feed your bun
1) Get some non-meat baby food, use a syringe to suck up the baby food, get a cup of hot water, dump the syringe in the hot water for 2 min., now the syringe is warm, so you now syringe feed the baby food to your bun.
Every 1Kg of bunny weight, get 100 ml of food inside him per 24 hr.
OR
2) Get some blackberry or raspberry, smash it via juicer. You need about 6 oz. Get some hay stem, cut the stem in 1 mm length, mixed it w/ the
blackberry. Put the mixture in a 35 ml syringe and force feed your bun. Your bun need the fiber to survive.
You need to force feed your bun via syringe.
Your bun would also need metacam, as they won't eat because they are in pain.
metacam dosage (make sure you use the :
dosage (in ml) = wt. in KG x 0.1 / 1.5 PER 24 hr.
for e.g., if your bun is 2.5KG then
dosage (in ml) = 2.5 KG x 0.1 / 1.5 = 0.17 ml
You can use metoclopramide:
For a large 5 - 6 KG bun, 3 ml every 8 to 12 hr.
For a small 2 to 3 KG bun, 1.2 to 1.4 ml every 8 to 12 hr., depends on how serious it is
The important question is, does your bun eat hay? If he doesn't eat hay, then the good news is:
this problem is cause by lack of fiber, just force feed w/ the above and sub-Q fluid will be fine
the bad news is, this will happen again due to lack of fiber
if you can get sub-Q fluid, then give 25 to 30 ml, 3 times every 24 hr., you need to super-charge your bun with fluid
The absolute best spot is the loose skin just behind the neck. See diagram
it's a very simple task:
1) You hold down the bun
2) lift the loose fur 2 inch from the back of his neck, now you form that empty air "pocket" from the diagram above
3) push the needle in, if it's a small bun, push in approx. just over 0.5 inch
4) release the valve from the NaCl tube
5) You'll notice the drip keep on coming from the valve
6) when done, turn off the valve and pull the needle out
P.S. When you buy the tube/valve kit, ask for the Macro Kit, the macro kit allows the NaCl to drip much faster into the body
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if you don't have sub-Q fluid (NaCl bag), then get him as much liquid as possible, force feed water more often, juice can also encourage your bun to drink more