I am always amazed at the level of research into the health of our dogs currently undertaken by UK universities. Here is an extract, from Dogslife, an organisation I support: The world’s oldest cancer (found in dogs) Scientists in the UK have recently decoded the DNA of cancer cells and compared them to the DNA of over 1,000 dogs and other canids, and estimated that the cancer may have dated back as far as 11,000 years. A very rare form of cancer called canine transmissible venereal tumour was evaluated. This tumour is believed to have originated in a single dog many years ago, and can still be found in dogs today across the world (although it is incredibly scarce). It is thought that the ancient dog in which the disease first developed was similar to a husky; scientists were able to identify that the dog was a breed similar to a wolf, probably had a grey-brown or black short straight coat, pricked ears, and was of medium size. For many years, the cancer only occurred in a secluded population of dogs. However in the last 500 years, the cancer has spread globally which is possibly due to dogs being taken with their owners when they have explored the world by travelling overseas. The cancer is passed on through mating, and the genome of the original ancient dog which first developed the cancer still survives today in the cancer cells it spawned. Most cancers are not transmissible, but this rare type of dog-transmissible cancer is spread sexually and causes genital tumours. The tumours usually regress within a few months, and previously infected dogs then have immunity. The tumours rarely spread to other parts of the body. Scientists have been able to date the dog-transmissible cancer’s origin to 11,000 years ago by decoding the genome of the cancer and studying the types of mutation present (which act as a “molecular clock”). Two tumours were sampled: one from a pure bred American Cocker Spaniel from Brazil, and one from a random-bred Australian Aboriginal camp dog. Amazingly, despite millions of genetic changes over time, the cancer has survived (although it is exceptionally uncommon) making it the oldest living cancer known in the world. By studying the genome of this type of dog cancer, researchers will be able to find out more about how this type of cancer becomes transmissible It is quite common for dogs to eat their own stools or those of other animals (this is termed “coprophagia”). Other species do it because it is an easily digestible source of protein or vegetation, but for pet dogs there is not always a specific explanation for this behaviour and it can be difficult to stop. Coprophagia may begin if dogs are hungry or do not have enough variety in their diet. By feeding them more times throughout the day (including 45 minutes before a walk), gradually adding variety to their diet and giving them things to chew, the condition may subside. In experiments dogs have also developed the habit due to a deficiency in dietary vitamins, although this would be a highly unlikely cause if dogs are fed a balanced diet. Dogs may just be curious about the taste, or like it, so by spraying something onto it that tastes unpleasant (which has been approved by your vet) dogs will be deterred from ingesting it. If dogs have been punished for going to the toilet in the wrong place, they may be eating it to avoid being told off. Furthermore, if a big fuss has been made when they have eaten it, they may think it is something of value and try and repeat the process before the material is cleaned up. Bitches that have had a litter of puppies and cleaned up after them may have coprophagia because they are continuing to clean up even after the pups have left. In puppies and young dogs, coprophagia may have begun because puppies have copied their mother’s behaviour and then continue to clean up. Some puppies may have started to play with and eat poo as something to do, and this behaviour has continued into adulthood. Lack of stimulation and exercise can lead to coprophagia so by treating boredom, dogs may stop. Overcoming coprophagia begins with recall training. This is best conducted in an area with no stool present so there is nothing to distract the dog. Once the dog is well trained in returning to its owner on demand, the recall command should be used out on walks as soon as the dog starts to look for stools, to lure them away from it, then praise and a treat given for coming back when called. By continuing to distract the dog away from the stool, they should begin to learn that they get a better reward if they come back to their owner instead. Some dogs may continue to eat matter when the owner isn’t looking. While this won’t harm the dog, it is very important to make sure their worming regime is kept up to date. Roger
Re: Animal Research Very interesting. Thank you Rodger. As you say it is amazing how much research is done for animals (thank goodness) and amazing the information that is now available through DNA .
