suckless

adj

1. (not-comparable)That does not suck or suckle.

   “‘No, I’ll not touch it: but it looks melancholy, does it not, Ellen?’ ‘Yes,’ I observed, ‘about as starved and suckless as you: your cheeks are bloodless […]”

   “Tube feeding is not as quick an emergency measure as the dextrose injection nor as long lasting in its energy boost, but is most useful for getting milk into the stomach of a suckless lamb.”