At 4:30 pm, being impatient at not hearing back from the vet, I called the surgery.
They told me that I could collect Freya if I wished but that she was still recovering from the sedative and that it might be better to leave her until the morning. Obviously, I would prefer to have her back with us, even if drowsy, but the important consideration was what is best from Freya.
After discussion, we left it that she would stay at the vet’s overnight to recover and that I would go to the surgery at 9:30 tomorrow morning to speak to the vet and collect her.
They said the blood was fine and there was “no sign of anything sinister”. That is good news, although it is slightly attenuated by not having any idea why Freya is not eating. Leaving her overnight also gives them a chance to get a urine sample: maybe that will provide a clue.
Tomorrow I will hear in detail what the vet has found out and, best of all, bring Freya home.
Thanks for your good wishes which are much appreciated.