Some dogs are cooperative and don't need to be sedated. Some won't lie still or even lie down and do need to be sedated. Personally, if I have to have a Grey sedated for xrays again I'm going to ask that they be completely knocked out. We had two Greys sedated since the first of the year and neither one of them did well on the drugs at all. It took one about 10 hours to come out of it and other about 13 hours and they were both a distressed panting mess until the drugs wore off. One of the drugs they gave them was butorphanol. The other was acepromazine. I've since heard people say they've had dogs have bad reactions to either one or both of those drugs. I won't let them use either of them again.