If my memory serves me right:
Cattle: 4 lbs grain to produce 1# meat.
Hogs: 3 lbs grain to produce 1# meat.
Poultry:2 lbs grain to produce 1# meat.
Fish: 1.5 lbs grain to produce 1# meat.
What is the ratio for rabbit?
My books, from when I home raised them in the late 70s early 80s pegged it at 4:1, but that may have improved with newer meat breeds.
OTOH, the fat, bone, and water-content ratios are much better per pound than for chicken.
I should add, that I never wanted for fishing worms, nor did I ever have better gardens, than when I raised rabbits.
I should add that the 4:1 is for pellets, not grain. The pellets are way less than half grain, and are mostly alfalfa.
"What is the ratio for rabbit?"
2 rabbits and 1 pound of grain produce 20 more rabbits ;)
Then add an extra pound of grain to make some pancakes for their heads.
1 .22 per 1.5-3.0lbs. of meat (depending upon the species}. If you git er done right!