I was recently contacted by a friend with a sick steer. She described his symptoms and I was concerned that is sounded quite serious, but I hesitated to recommend that she called a vet. Unfortunately the animal later died, which confirmed my suspicions, however we were both comfortable that she did all she could to save him.
I hesitated for a couple of reasons:
Calling a vet out after hours can be expensive, often more than the animal is worth (and I checked that this was livestock rather than a pet)
There's not always much a vet can do for sick cattle other than give antibiotics and hydration, which may not have saved him