RRR, Sorry about your rabbits! That heat you all are getting is rediculous!
With ultralean wild meat, like others have already said - you must add fat! Pork, Beef, even schmaltz has been used. Try to keep the ratio at about 85% - 90% lean meat to 10% - 15% fat. We tend towards the leaner ratios.
We also go to the meat store intown and pick up bulk pork/beef/animal fat, it's pretty cheap.
Don't be afraid to experiment because in the vast majority of the test sausages, even the failures can be eaten or used in something else!
Vman, we tried the Bacon grease suggestion, when we experimented, we kept it and the meat very chilled while grinding and blending. And we did discover that you can have too much of a good thing in a couple of batches. Picture in your mind; sausage skins splitting, exploding bacon grease geysers! Ah, the early days of meat experiments! We now just use actual bacon, I like jowl bacon when I can get it for my sausages.
I am a bit of a bacon fanatic. (we need a BACON Smiley!)
Vman and Cg, I am a flytyer and experimented with marmot (body and tail) furs and I kind of like the buggy look it gives to my nymphs. It is not the greatest but for the cost of a .22 round, it is cheap. Marmot is basically Alaskan Rockchuck. Long and slow cooking with herbs and onions, carrots, taters and celery.
Cg, thanks for vote of sausage confidence! I am by no means a master as much I am a mad meat experimenter! Thankfully, my wife still lets me use the kitchen and still tries many of the meals I offer her.
tnoodle, I haven't tried adding pre made sausage before, heck, I never even thought of it but I may use that for some sausages later this year. A neat shortcut for flavoring some sausages - thanks.