It is a bit of a coin toss I think. Some nurse cows seem to take to their jobs rather readily. Some may require coaxing. Hobbles may be needed or maybe hold in place/stanchion, with a rear leg tied ,till she gets the idea. Sort of like what you might do with an ornry milk cow (at least to you get fed up and send her down the road). The trick is to get them to bond if at all possible. Try to work out a routine, as we know, cows like routines. I do not know if I was just plain lucky or the cow had a sense of humor but I wiped a nurse cow down real well with a bath towel then rubbed the calf all overl with the same towel. I was trying to transfer some recognizable smell to the calf. Anyway, the calf didn't miss any meals. I have read of folks skinning a stillborn calf and layin the hide on an orphan calf...same basic idea I suppose. Good luck.