Most people will not even notice this particular organ as - apart from a well known maintenance behaviour - most dogs keep it well under control; but there is no prize for guessing why their breath can have such an evil smell at certain times.

Our young Tudor is different because he is easily the most nervous dog I have ever encountered. We first noticed his glandular prowess after he had just met his first horse. The creature had ambled by in a flatulently peaceful manner and pretended that Tudor was just another puff of air. Tudor, on the other hand, had never seen anything quite like this in his life before. He barked furiously, hid his tail and then tried to get away as fast as possible. This rather clever escape plan that was instantly foiled by the power of the human voice. There was a peculiar smell, but in our ignorance we blamed the horse.

When the three of us drove off in the car, the smell became unbearable. We gave each other accusing looks and exchanged humorous and/or insulting remarks, until the origin of the new aroma became obvious, because Tudor started to deal with its source.

I don't think this particular gas has ever been scientifically analysed, but I wouldn't be at all surprised if it didn't turn out to be something like H2SOstink.

It is difficult to describe this whiff adequately. Imagine a very ancient fish that has hidden at the bottom of an over-used sewer and died there of fright. All of its relatives have come to the wake and have expired as well. You turn up a week later to study their remains - you smell them before you see them. This image just about begins to describe the astonishingly pungent pong that can fill a house in seconds. When it is trapped inside a car no amount of open windows, high speed or even removal of the offending collie will shift it. Since this first adventure Tudor has released his panic smell every time he gets seriously frightened. He is not very discriminating in this: a loud noise, a sudden visitor, a strange animal, the postman - anything is yeast to this particular fermentation process. What is worse, we can't think of a way to stop it. If we praise him, he will stink the place out in order to do us a favour, if we tell him off, he will do the same thing because he feels frightened.

As far as we can make out there is nothing that can be done. Dogs are distant relatives of skunk like creatures and our Tudor seems to be the missing link. I forget how often we thought that he had finally grown out of the habit, only to be suddenly reminded that he had just spent his time perfecting a more pungent brew.

So be it, the pup is well worth it!