I have been told by my vet that it can take their colostrum from there bag that the calf needs in it's first hours after birth cause I had a yearling heifer nurse on a cow of mine before she gave birth. So my vet recommended giving colostrum at birth just to be on the safe side and everything worked good for me. At a 283 day gestation table she would of been due May 21. I think she took from AI if she is bagged up, but is 2 weeks past. Has she lost her mucus plug or having any mucus discharge with swollen vulva? I just don't think she would be bagged up already if she took from the bull being in October, especially if she had dried up after being weaned from her last calf. Either way if she had been nursed on, I would give colostrum just after birth to be on the safe side.