by Jette Eva Madsen.

Norwegian Forest Cats are very healthy breeding cats. Norwegian Forest Cats have no inheritable diseases. Norwegian Forest Cats are psychologically strong cats that easily handle the pregnancy, delivery, and upbringing of kittens.

We have always been very proud about our very healthy breed. It has always been a good breed for inexperienced breeders to start out with because NFC usually do not have a very complicated temper.

However as time goes by it seems as if the common belief about the health of our breed is reflecting the truth less and less since smaller defects and even serious inheritable diseases slowly appears in the breed.

Looking at the history of breeding of the older breeds of cats and the breeding of dogs and other pet-animals it is not difficult to understand why the breeders of NFC slowly get more and more defects and problems into the breed. It is however difficult to understand why new breeders like the ones of NFC have not been able to learn of the mistakes that were made by breeders of other cats and other animals.

What went wrong? - The answer is quite easy:

The breeders incredible ambitions combined with too little knowledge of health, physiology and genetics.

Ambitions is a natural and healthy trait as long as the breeders are still able to do the right things, but some breeders and exhibitors will do nearly everything in order to breed successful cats. If a cat with a smaller but invisible defect possess excellent show potential this cat will be shown and possibly breed regardless of the defect. As a result other breeders will want to buy kittens after this beautiful show cat and offer high prises for the kittens. The general breeder does not see that to breed one cat with a small problem poses a great risk to the breed. The problem in the long run is however that this happens for every breeder and if several of these breeders decide to keep a cat with a defect or problem the breed will eventually be effected seriously.

The second problem: education of breeders can be helped. The most difficult part here is the breeders that believe they know everything and therefore have no interest in reading or listening about other breeders experiences.

Being a breeder is a never ending education. Every time a litter of kittens is born new problems appear and new things are to be learned. As breeders we have a duty to deliver every generation of Norwegian Forest Cats in better condition than the condition in which the parent generation was handed over to us.

All of these defects and disease’s are inheritable. The basis for them are however very different. I will group them in tree different groups where some defects will fit in two or all groups.

  1. The defects caused by inbreeding of cats that carry recessive unwished or directly harmful characteristic in their genes.
  2. Defects related to breeding after "hyper type".
  3. Defects related to the change in habitat/surroundings of the NFC.

The defects in group 1 can be based on one gene or more genes. The one gene defects will usually have a recessive nature so that you do not see the defects on the parents. If the parents are related the chance that both share a common defect is quite large and in that case 25% of the offspring’s will be homozygotic for the defect, 50% will be carriers, and 25% will be free of defects.

The defects based on more genes is said to have polygenetic inheritance. Some traits or defects will show a gliding change from no expression to a severe fault depending on the number of harmful polygenes the cat has for this trait. Other traits with polygenetic inheritance will not be expressed before the cat have a certain number of harmful genes for this trait and there will be no gliding change. This kind of traits is said to have a polygenetic threshold mode of inheritance.

The defects caused by one gene:

  • Dermatosparaksis
  • GSD

Defects caused by polygenetic inheritance:

  • Patella Luxation
  • Umbilical Hernia
  • Heart Fault
  • Cleft Palate
  • Tail Fault
  • Swimmers chest
  • "Frog legs"
  • Typerelated faults
  • Faults related to the behaviour

A grouping of the defects and unwished traits after their basis will be like this:

Defects caused by a greater degree of inbreeding than the random breeding the cats performed in the nature:

  • Patella luxation
  • Different kind of heart faults
  • Swimmers chest
  • "Frog legs"
  • Umbilical hernia
  • Cleft palate
  • Tail fault
  • Dermatosparaxis
  • GSD

In nature it is very unlikely that two individuals carrying the same genes will ever meet because in nature the breeding usually is totally at random. The minute we start the breeding of animals we start to increase the degree of inbreeding. Even though we cannot see the same names on the pedigrees of our cats it is a fact that most of our cats have just a slightly higher degree of inbreeding than their brothers and sisters in nature. Just the fact that most of our cats will have the first TRULS amongst their ancestors if we go back far enough show that they are a bit more inbreed than they were when they roamed around in nature.

Defects caused by breeding for a certain type of cat:

  • Shorter coat
  • Narrow jaws and problems with the bite
  • Wrong placing of the eyes
  • Pig tail
  • Smaller cats
  • Slimmer cats

When we breed we have a written standard of the perfect cat. A lot of breeders will hunt this certain preferred type and along the road they will some times reach a point where the standard becomes too extreme and / or unhealthy. Most breeders will stop before this happens because they see that the type of their cats develop in an unhealthy direction. Sometimes a breeder will not discover what happens or even worse he has a lot of show success with this type of cat despite the fact that the type is too extreme and he decide to go on with that kind of cat.

Unwanted traits caused by the change in the natural habitat of the Norwegian Forest Cat:

  • Larger litters of kittens
  • Females that give birth to very big kittens
  • Females that come into heat all year
  • Cats that need help in order to mate
  • Females that need help with the labour
  • Females that need help with nursing their kittens
  • Los of hair on the outside and on the inside of the ears

When we decided to breed the Forest Cat we took on a great responsibility at the same time. In nature the rule of survival of the fittest will make sure that cats who deviate from the optimal behaviour of the breed will not be able to produce kittens and pass on their genes to the next generation.

In nature a lot of traits will prove to be disadvantageous because the amount of food is be limited, the weather is cold and wet, etc. When we breed we often have difficulty detecting this group of changes and often we are very proud of these changes mistaking them for cats being very sweet and dependant on us (problems with nursing - labour - etc.) or being extremely healthy breeders (large litters - big kittens - etc.)