Another thought-
did she just wean a BIG calf recently. its stressful for a heifer to raise a nice calf, breed back, and grow all at hte same time, but it must be done if she wants to stick around. Sometimes heifers will abort or have a weak second calf if the first calf isnt weaned in plenty of time for her to recover before number 2.
I have pulled RP out before at feeding time when cows were distracted with hay but if it doesnt come right out i leave it alone. although not recommended to pull it, a lot of times they jsut step on it and rip it out anyway..you might try tying it into a knot as dun has suggested many times before and let gravity work it on out. whatever you do, do not get the smell on your hands, i repeat, DO NOT get the smell on your hands!