We have found through scientific methods and observation the adverse affects of pain on our pets. I remember when vets didn't bother with painkillers for routine surgeries such as desexing and teeth scaling. Since then, we have discovered that management of pain throughout the course of surgery and thereafter reduces anaesthetic risks and speeds up post-surgical recovery.

It has always amazed me the tolerance for pain that some animals exhibit. For example, it is very common to find a rabbit with a broken leg, its fractured bones protruding through the skin, happily eating and exhibiting normal behaviour despite its severe disability. It shocks me even more how many owners refuse treatment because of the cost and the apparent pain tolerance these animals are showing. These owners think that since the animal is still eating and drinking, it can't be in that much pain.

How wrong they are. This high pain tolerance is a trait that improves animals' survival chances in the wild. It is common knowledge that despite the ferocity of carnivores like the great cats of the African plains, they will select easy prey rather than confront larger, healthier targets, such as adult wildebeests. This helps the carnivore conserve energy and minimise the chances of injury during the hunt.

So what can a sick or lame animal do to minimise it being singled out of the pack for carnivore food? They keep their pain hidden for as long as possible, until the pain causes an unmanageable disability or is resolved. This strategy may be fine in the wild, but with pets it hinders the owner's ability to detect the problem earlier and initiate timely treatment.

Fortunately for our four-legged friends, they are not as good at hiding pain as they think they are. Many of my better clients are hypersensitive to any changes in their pet's normal behaviour patterns, and they often present their pets to me before any overt symptoms are visible. One thing I have learned over the years is to trust the client's intuition, because they have gone to all that trouble to seek medical advice during their busy day, and nobody wants to visit the doctor unless they have to. It does make the consultation more challenging because of the lack of obvious symptoms or diagnostic paths. But lo and behold, with persistence, we often are able to find something to work on during the course of a general consultation.

A memorable example was a lady who came in with a Pomeranian. It was clear to her that the dog was not well. But all we had to go on from the medical history was something vague the owner said. It went something like: 'I don't know exactly what is wrong with her, she is just not eating with the same passion as usual, but she still eats and is keeping her weight.' On the examination table, everything checked out normally. The dog had seen several other vets for the same problem and the woman was advised to observe her pet for longer.

Which seemed reasonable to me, given the lack of clinical findings. The dog was again bright and alert and a thorough body check, including a full blood biochemistry, had revealed nothing. Normally we would have stopped the investigation there due to the lack of evidence. But the distraught owner insisted that there had to be something wrong, so we performed an ultrasound of the abdomen, not knowing what we were looking for.

On the ultrasound I found a small, circular shape in the small intestines. I told the owner in no uncertain terms that the small shape in question could be just some undigested material on its way out, or it could be just an ultrasound error. There wasn't enough evidence for surgery, so I told the owner to come back in two days to see if the round shape was still there - and it was. So we decided after much deliberation about the risks of surgery to open her abdomen to have a look. It turned out to be a malignant intestinal tumour. My great aunt recently died from an intestinal tumour because, typically for this type of tumour, it was discovered too late.

In the dog's case, the surgery saved its life, all because of a very observant owner.

I remember when vets didn't bother with painkillers for routine surgeries such as desexing.