We are lucky enough to have a great vet practice just 4 miles away. They have half their team dedicated to small animals and the other half to large animals, although they can each do the other bit if necessary. The small animal bills are always much bigger than the large animal ones, but they have to earn their money somehow, and I suppose it's the income from the small animal stuff which enables them to continue providing such good support for farmers.
We are very happy with the care all our animals have been given over the years.
Incidentally, it will save a lot to take your farm animals down to the surgery rather than get the vet out. For example, in the past we have stuck a labouring Jacob ewe in the back of the Land Rover, and come home with a ewe and two lambs, safely delivered (they would have all been lost at home). Similarly when one of our Jacob lambs broke off his horn with some skull plate attached, we took him down immediately so he was treated quickly. If we had had to wait for a home visit he might have died of catastrophic blood loss (it was quite impressive). Each visit teaches us something, so next time we can deal with that problem ourselves. I wonder if sometimes when the vet works hard on an animal but still loses it, if that isn't because the owners have tried to treat it themselves and the problem has gone on so long that it is a lost cause. The bill will be high because more complex treatment is needed than if the vet had been consulted at the beginning, but you've lost the animal anyway.