Every week I make a note of weight (and if theyve gained or lost any). I check teeth, ears, eyes, bum, bits, skin ect. I even right down when nails and spurs are done. As soon as there's anything out of the ordinary or I'm not sure of I make a note and keep an eye on it for the next week. If it's something requiring immediate attention then I will not wait.
I keep a record of when they go to the vets and what for as well as what they prescribed inc dosage.
I'm just a bit OTT though and have had animals respond badly to certain meds. Sometimes in an emergency it's best to know what, when and who as sometimes it's a rush and vets need background quickly especially when it's not a vet you don't usually see.
My vets seem to appreciate the knowledge and remembering important information given by them. When I went to the vets after a castration on my Basil, they literally asked me 'have you read up on the different methods?' followed by 'its a refreshing to to have someone who knows procedure and the aftercare. Makes things easier'. I imagine after having a few difficult clients or just a long day, it would be. Remember, vets are only human and treat creatures that can't tell them what's wrong. So knowing your piggies normal, and noting when things start drifting can really help with diagnosis especially if it's a gradual type of thing.