05-10-2009, 05:37 PM #1
Brother/Sister breeding and other inbreeding..good or bad?
I dont know much about genetics with dogs. I do know that close breeding in humans can lead to a whole host of problems. Ive heard mixed things about close interbreading of dogs and wanted to know other people's opinions about the matter. is it alright? what can go wrong? are they more prone to health problems or less? What got me wondering was a close brother sister breeding of some of Tom Garner's pups. I know he has a good reputation and breeds really good dogs. I am considering getting in touch with him next spring about a dog. Here is a link to what I am talking about.
is this ok to do?
05-10-2009, 05:42 PM #2
I'm definitely no expert but I would be concerned because it does not look like there was only one brother/sister breeding but that the pups produced were from mulitple sibling breedings, meaning that the parents, and grandparents were bred the same way...
That'd be my concern, I think one sibling breeding in the line would be fine but I would be worried because it's happening repeatedly in the same pups ped so close in generations.
He's one of the few people I'm not too worried about that in. I've seen his dogs and he can get away with breeding real tight like that because he knows what he's doing and he has the gene pool he's working with cleaned up pretty well. He seems to know what recessive traits will come into play with what breeding.
PROS AND CONS OF INBREEDING
Copyright 1996, Sarah Hartwell
Adapted, with permission, from Cat Recourse Archive and edited by Dog Breed Info.
Inbreeding is the mating together of closely related dogs, for example mother/son, father/daughter and sibling/sibling matings. For breeders, it is a useful way of fixing traits in a breed - the pedigrees of some exhibition dogs show that many of their forebears are closely related. For example, there is a famous cat by the name of Fan Tee Cee (shown in the 1960s and 1970s) appeared in more and more Siamese pedigrees, sometimes several times in a single pedigree, as breeders were anxious to make their lines more typey. Superb specimens are always much sought after for stud services or offspring (unless they have already been neutered!) having won the approval of show judges.
However, inbreeding holds potential problems. The limited genepool caused by continued inbreeding means that deleterious genes become widespread and the breed loses vigor. Laboratory animal suppliers depend on this to create uniform strains of animal which are immuno-depressed or breed true for a particular disorder e.g. epilepsy. Such animals are so inbred as to be genetically identical (clones!), a situation normally only seen in identical twins. Similarly, a controlled amount of inbreeding can be used to fix desirable traits in farm livestock e.g. milk yield, lean/fat ratios, rate of growth etc.
NATURAL OCCURRENCE OF INBREEDING
This is not to say that inbreeding does not occur naturally. A wolf pack, which is isolated from other wolf packs, by geographical or other factors, can become very inbred. The effect of any deleterious genes becomes noticeable in later generations as the majority of the offspring inherit these genes. Scientists have discovered that wolfs, even if living in different areas, are genetically very similar. Possibly the desolation of their natural habitat has drastically reduced wolf numbers in the past crating a genetic bottleneck.
In the wolf, the lack of genetic diversity makes them susceptible to disease since they lack the ability to resist certain viruses. Extreme inbreeding affects their reproductive success with small litter sizes and high mortality rates. Some scientists hope that they can developed a more varied gene pool by introducing wolfs from other areas into the inbred wolf packs.
Another animal suffering from the effects of inbreeding is the Giant Panda. As with the wolf, this has led to poor fertility among Pandas and high infant mortality rates. As Panda populations become more isolated from one another (due to humans blocking the routes which Pandas once used to move from one area to another), Pandas have greater difficulty in finding a mate with a different mix of genes and breed less successfully.
In cats natural isolation and inbreeding have given rise to domestic breeds such as the Manx which developed on an island so that the gene for taillessness became widespread despite the problems associated with it.
Apart from the odd cat jumping ship on the Isle of Man, there was little outcrossing and the effect of inbreeding is reflected in smaller-than-average litter sizes (geneticists believe that more Manx kittens than previously thought are reabsorbed due to genetic abnormality), stillbirths and spinal abnormalities which diligent breeders have worked so hard to eliminate.
Some feral colonies become highly inbred due to being isolated from other cats (e.g. on a remote farm) or because other potential mates in the area have been neutered, removing them from the gene pool.
Most cat workers dealing with ferals have encountered some of the effects of inbreeding. Within such colonies there may be a higher than average occurrence of certain traits. Some are not serious e.g. a predominance of calico pattern cats. Other inherited traits which can be found in greater than average numbers in inbred colonies include polydactyly (the most extreme case reported so far being an
American cat with 9 toes on each foot), dwarfism (although dwarf female cats can have problems when try to deliver kittens due to the kittens' head size), other structural deformities or a predisposition to certain inheritable conditions.
The ultimate result of continued inbreeding is terminal lack of vigor and probable extinction as the gene pool contracts, fertility decreases, abnormalities increase and mortality rates rise.
Artificial isolation (selective breeding) produces a similar effect. When creating a new breed from an attractive mutation, the gene pool is initially necessarily small with frequent matings between related dogs. Some breeds which resulted from spontaneous mutation have been fraught with problems such as the Bulldog. Problems such as hip dysplasia and achalasia in the German Shepherd and patella luxation are more common in certain breeds and breeding lines than in others, suggesting that past inbreeding has distributed the faulty genes. Selecting suitable outcrosses can reintroduce healthy genes, which might otherwise be lost, without adversely affecting type.
Zoos engaged in captive breeding programs are aware of this need to outcross their own stock to animals from other collections. Captive populations are at risk from inbreeding since relatively few mates are available to the animals, hence zoos must borrow animals from each other in order to maintain the genetic diversity of offspring.
Inbreeding holds problems for anyone involved in animal husbandry - from canary fanciers to farmers. Attempts to change the appearance of the Pug in attempts to have a flatter face and a rounder head resulted in more c-sections being required and other congenital problems. Some of these breeds are loosing there natural ability to give birth without human assistance.
In the dog world, a number of breeds now exhibit hereditary faults due to the over-use of a particularly "typey" stud which was later found to carry a gene detrimental to health. By the time the problems came to light they had already become widespread as the stud had been extensively used to "improve" the breed. In the past some breeds were crossed with dogs from different breeds in order to improve type, but nowadays the emphasis is on preserving breed purity and avoiding mongrels.
Those involved with minority breeds (rare breeds) of livestock face a dilemma as they try to balance purity against the risk of genetic conformity.
Enthusiasts preserve minority breeds because their genes may prove useful to farmers in the future, but at the same time the low numbers of the breed involved means that it runs the risk of becoming unhealthily inbred. When trying to bring a breed back from the point of extinction, the introduction of "new blood" through crossing with an unrelated breed is usually a last resort because it can change the very character of the breed being preserved. In livestock, successive generations of progeny must be bred back to a purebred ancestor for 6 - 8 generations before the offspring can be considered purebred themselves.
In the dog fancy, breed purity is equally desirable, but can be taken to ridiculous lengths. Some fancies will not recognize "hybrid" breeds such as the white or Parti-Schnauzer because it produces variants.
Breeds which cannot produce some degree of variability among their offspring risk finding themselves in the same predicament as wolfs and Giant Pandas.
Such fancies have lost sight of the fact that they are registering "pedigree" dogs, not "pure-bred" dogs, especially since they may recognize breeds which require occasional outcrossing to maintain type!
IMPLICATIONS OF INBREEDING FOR THE DOG BREEDER
Most dog breeders are well aware of potential pitfalls associated with inbreeding although it is tempting for a novice to continue to use one or two closely related lines in order to preserve or improve type.
Breeding to an unrelated line of the same breed (where possible) or outcrossing to another breed (where permissible) can ensure vigor.
Despite the risk of importing a few undesirable traits which may take a while to breed out, outcrossing can prevent a breed from stagnating by introducing fresh genes into the gene pool. It is important to outcross to a variety of different dogs, considered to be genetically "sound" (do any of their previous offspring exhibit undesirable traits?) and preferably not closely related to each other.
How can you tell if a breed or line is becoming too closely inbred? One sign is that of reduced fertility in either males or females. Male dogs are known to have a low fertility rate. Small litter sizes and high puppy mortality on a regular basis indicates that the dogs may be becoming too closely related. The loss of a large proportion of dogs to one disease indicates that the dogs are losing/have lost immune system diversity. If 50% of individuals in a breeding program die of a simple infection, there is cause for concern.
Highly inbred dogs also display abnormalities on a regular basis as "bad" genes become more widespread. These abnormalities can be simple undesirable characteristics such as misaligned jaws (poor bite) or more serious deformities.
Sometimes a fault can be traced to a single male or female which should be removed from the breeding program even if it does exhibit exceptional type. If its previous progeny are already breeding it's tempting to think "Pandora's Box is already open and the damage done so I'll turn a blind eye". Ignoring the fault and continuing to breed from the dog will cause the faulty genes to become even more widespread in the breed, causing problems later on if its descendants are bred together.
In cats, one breed which was almost lost because of inbreeding is the American Bobtail. Inexperienced breeders tried to produce a colorpoint bobtailed cat with white boots and white blaze and which bred true for type and color, but only succeeded in producing unhealthy inbred cats with poor temperaments.
A later breeder had to outcross the small fine-boned cats she took on, at the same time abandoning the rules governing color and pattern, in order to reproduce the large, robust cats required by the standard and get the breed on a sound genetic footing.
Inbreeding is a two-edged sword. On the one hand a certain amount of inbreeding can fix and improve type to produce excellent quality animals. On the other hand, excessive inbreeding can limit the gene pool so that the breed loses vigor. Breeds in the early stages of development are most vulnerable as numbers are small and the dogs may be closely related to one another. It is up to the responsible breeder to balance inbreeding against crossings with unrelated dogs in order to maintain the overall health of the line or breed concerned.
PROS AND CONS OF INBREEDING DOGS, Inbreeding Dogs
05-10-2009, 06:50 PM #6
thanks for that Marty, very informative. Heres a hypothetical question for you. Would you want or purchase or even take, if given, a dog from the Garner litter whos had such tight brother sister breeding above? Do you think that those dogs will have less vigor or have other problems?
Last edited by mandreweav; 05-10-2009 at 06:52 PM.
As long as you A. know what you are doing and B. Cull HARD I don't see a problem with it.
I've made a breeding like this myself and have no problem's, I feel myself not over two time's of back to back inbreeding is fine, keep going and you'll get retarded dogs... Garner know's what he's doing though ;)
My brother x sister breeding and as tight as I'll go...
ONLINE PEDIGREES ::  :: AKA X FINALE
Last edited by Marty; 05-10-2009 at 07:04 PM.
05-10-2009, 07:05 PM #9
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- Apr 2007
- pssst......Right behind you
I agree with NC and Penn on this. I have 2 VERY inbred pups.
Last edited by Cynthia; 05-10-2009 at 07:08 PM. Reason: Spacing
05-10-2009, 07:09 PM #10
if it is a very experienced breeder who has studied the genetics then it can be ok jakes mom and dad are half siblings
PROS AND CONS OF INBREEDING DOGS, Inbreeding Dogs
There is nothing wrong with dog inbreeding as long as the breeder understands the genetics and is a dedicated breeder and will cull dogs that have issues. NOTHING WRONG at all. You just need to have knowledge on this type of thing, thus you will not breed dogs from the inbreeding that are unsound.
For example, you inbreed a brother and sister. They have a litter of 10. 3 of the offspring are GREAT. But the other 7 have some issues. So you DO NOT BREED the 7 that have issues. But you breed the 3 that have no issues. Then this offspring you get 5 sound dogs and 6 unsound dogs. So you cull the 6 unsound dogs. And you breen the sound dogs. And eventually if you keep doing this and being dedicated, you will have more sound dogs then unsound dogs and then no unsound dogs if you keep doing it -- repeating the process from the litter and those dogs will have very very similar genetic traits..
In short: Theres nothing wrong with inbreeding as long as the breeder is dedicated and knowledge on this subject.
Search inbreeding on this forum . I remember I made a thread about this a while back. Screaming eagle posted good info regarding this. He even tought me that humans that inbreed can be perfectly normal.. its a misconception
Last edited by Jelet; 05-10-2009 at 08:04 PM.
05-10-2009, 08:02 PM #12
Preciate the input guys. I figured he knows enough about what he's doing to not produce inferior dogs from health riddled parents and I know hes got the best interest for the breed at heart. Ive seen some closely related breedings, just not that close so it just struck me as strange i guess. Honestly I still dont know if i would purchase a dog that closely bred, I would have to see how some of those dogs turned out.
05-10-2009, 08:12 PM #13
Last edited by mandreweav; 05-10-2009 at 08:16 PM.
check this out.
Pharols use to have babies with there sisters and the kids came out fine. But they didnt do this for a long time so they didnt run into problems. if u keep on inbreeding and inbreeding and inbreeding, then you will end up with problems. im not really sure on the human inbreeding but i do know you could have babies with your sister and the children can be perfectly fine. But i think if they keep on inbreeding for a long time with there kids doing it with there children ect. then u end up with problems.
Last edited by Jelet; 05-10-2009 at 08:21 PM.
05-10-2009, 09:46 PM #15Diamond Member
- Join Date
- May 2007
If you know what you are doing, then it can turn out great. If you don't, it can be really bad.
05-11-2009, 03:24 AM #16
tom garner obviously knows what hes doing and produces great dogs and im sure if he thought the dog was right then it would be just that. but the main thing that would be in the back of my mind would be the dog developing something later on in life as unlikely as it might be. its probably no more likely than any other dog to develop something but i just would probably not choose that litter if i were to ever get a dog from him. If they turned out to be superior specimens to start with i would definetely give it some serious consideration.
05-11-2009, 07:39 AM #17Diamond Member
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- May 2007
TG is definitely one who knows what he is doing, and you are more likely than not to end up with a great dog.
05-22-2009, 02:53 PM #18Junior Member
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- Apr 2009
- where i want
depends on how true the blood is understand. to tight it will start to slow down. most folks realy have know idea as to why there breeding so tight other then to say they have a certain % of blood. TRUTH be told you breed good dog to good dog. breeding blood gives you "german shepherds " no matter what so called " famous " dog your inbreeding on.
05-28-2009, 02:42 AM #19
05-31-2009, 03:21 PM #20
I don't know about the dog world. But in the horse world, when closely related horses are bred and the resultings foal is nice. It's considered "Line breeding" if the resulting foal is less than desirable, it's considered "inbreeding"
Sometimes it works, sometimes it doesn't. Do you want to take the chance?
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