American Fancy Rat & Mouse Association

This article is from the Nov./Dec. 1987 AFRMA Rat & Mouse Tales news-magazine.

Inbreeding and the Rat Fancy

By John Wells, N.F.R.S., England

Contributed by Nick Mays, President, National Fancy Rat Society, England. First published in No. 40 July/August 1987 edition of Pro-Rat-a, the National Fancy Rat Society Journal.

Charles Darwin is acknowledged as the founder of the accepted theory of evolution. Summarised his theory is that within each species of wild animal, variation occurs, individuals differ in size, colour, speed, intelligence, and a multitude of other features. In nature, it is the individuals which are best suited to the environment that survive to breed and pass on their qualities to the next generation. This is called Natural Selection, by which, over millions of years, all animals have and continue to evolve to suit the changing environment.

What’s all this got to do with Fancy rats? Charles Darwin also studied domestic livestock and recognised that animal breeders by using a system of artificial selection (selective breeding), can dramatically change the appearance and/or performance of a species of an animal. Every breed of domestic livestock whether it is cat, dog, rabbit, cow, pig, canary, pigeon, mouse, or rat, has in its origins a wild ancestry. Man, by exploiting mutations and natural variation, has changed the original stock in diverse and dramatic ways. Consider the massive Shire horse, the diminutive Shetland pony, and the quick Thoroughbred racehorse. All originate from the same wild stock. Whilst the rat does not have such divergent breeds, it does have a growing number of varieties which are being developed.

If you study the history of different forms of livestock, you will find that almost without exception, inbreeding has been used in the creation and perpetuation of breeds. A classic example is the Thoroughbred racehorse which originates from just three 18th century Arab stallions.

What is inbreeding? It is simply the breeding together of related individuals, from as close as brother to sister to much more distant relations. It is often said that inbreeding produces freaks and weakling stock. Yes, close inbreeding can produce freaks or inherited diseases; because two animals are closely related, they are more likely to both carry a recessive faulty gene passed down undetected from a common ancestor. Used indiscriminately, close inbreeding will in time produce a strain of uniformly mediocre rats. The key word is selection. Only the best examples should be used for breeding. In the same way that nature selects the fittest to breed in natural selection, the fancier must select only those resembling his ideal for artificial selection.

Let me give an example of the potential advantages and pitfalls of inbreeding. The aim of the breeder of the Hooded rat is to produce a rat with markings covering the head and shoulders with a narrow stripe extending from the hood to the base of the tail. Using inbreeding, he will select those individuals which most resemble the ideal for breeding. The pitfall is that he may select for markings without considering type, size, or other features. The result may be a strain of rats excelling in markings, but with poor type or lacking size. Now, nature does not discriminate between good and bad points. It is just as easy to produce an inbred strain of poor rats (probably easier). The breeder must be able to select those animals which as far as possible excel in all parts of the standard and take care not to breed from two animals which have the same fault. Responsibility also lies with judges. Whilst judges favour well-marked small adults, there is less incentive to breed for size. Having said that, the small marked rat may win its class, but stands little chance against the long typy Cinnamon Pearl or Silver Fawn.

I believe it is important when inbreeding to keep written records. In a very small stud you may be able to keep information in your head, but time fades and distorts memories. I keep a ‘stud book’ which has several pages for each rat kept, its parentage, its qualities and faults. Record is kept of each rat’s performance at shows and record is kept of each mating, the quality of young produced, and the names of young retained. In the case of Hoodeds, I make a diagram or ideally take a photograph of markings. Each rat has a name; I name all my rats after racehorses, names like ‘Dancing Brave’ or ‘Indian Skimmer’ are much easier to remember than just numbers. After only 2 years, I am able to trace pedigrees back up to five generations. Whilst pedigree alone is not used to make pairings, by looking back on past performance of breeding methods I am able to influence my thinkings on future pairings.

Now I can imagine that some of you may be saying that this is all rather intense, “after all we only keep rats for fun.” So excuse me whilst I get up on my soapbox.

The Rat Fancy has come a long way in the last 10 years. From the early foundations laid by Geoff Izzard and Joan Pearce, we now have a Fancy which is hopefully here to stay. We are still very much a new Fancy. Our superior organization puts many longer Fancies to shame; however, we must also not lose sight of the rats. Until the N.F.R.S. was formed, rats had not to any extent been selectively bred for over 40 years. Fortunately, most of the colour mutations had survived and new ones have occurred since. Over the last 10 years, fanciers have worked on varieties and some established strains have been developed notably in Silver Fawn, Cinnamon, Pearl, and Siamese. It is still early days; I am sure fanciers will agree that even the best strains could be improved. Some varieties have had little work done and are only a little better than pet quality.

If we are to hold our heads high alongside long established Fancies like rabbits, cavies, and mice, we must strive to improve the quality and variety of rats.

In my view, we need more fanciers which would in itself mean greater competition and a resulting improvement in quality. There is out there a potential population of small livestock fanciers. If our Fancy is to grow, we must attract more of them to rats. If we are to do this, we must project an image of an enjoyable hobby with a serious competitive element. The N.F.R.S. is unique in that is has a high public profile encouraging rats as pets. You only have to see the interest in our publicity stand at public shows to realise the value of N.F.R.S. publicity and promotions. The interest created in rats can only help the future of the Fancy. As public awareness increases, potential fanciers are more likely to take up rats. What today’s rat fanciers must do is ensure that there is quality rats for them when they do. I have a dream that in the next 5 years we double the number of people showing rats—just imagine the London Championship with over 200 quality rats entered.

In answer to the critics, yes we do keep rats for fun, but whilst we do, why not make the results of our hobby of quality and worth and ensure the continued growth of the N.F.R.S..

I hope to write in a future article about Line Breeding, Outcrossing, Double Line Systems, and other breeding systems. In the meantime, I can thoroughly recommend Practical Inbreeding by W. Watmough, published by Fur and Feather, as an interesting insight into the subject. *

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June 26, 2014