Hybrid Vigor

[Salzer mtn]

I've read most of the old post that has this word in it but i still have some questions about hybrid vigor. What does a dog act like that has lost it's hybrid vigor ? What does a dog act like that has hybrid vigor ? One person said the dog has high energy, does that mean the dog is hyper ? From what i read one of the reason breeders of closs linebred or inbred dogs make a out cross is to bring back in hybrid vigor, and from what i read it is best to out cross to another line of similar traits and line bred or inbred dogs. So another question is if i make this outcross of my linebred or inbred dogs because i want hybrid vogor to another line of linebred or inbred dogs, what if the outcross line needs hybrid vigor, will the combination of both lines produce hybrid vigor anyway ?

[hookset]

Hybrid Vigor is not a single trait. It simply means that the outcross (hybrid of two separate strains of something...) will usually be healthier, or some traits may be appear more pronounced. They way I explain it is...breed two highly bred dogs, and you have to be careful with worming, shots, etc. to ensure healthy pups.
Now look at a neighborhood roaming mutt. That motley old mutt can breed with another motley old mutt and receive not worming vaccinations and have healthy pups. The pups are never wormed or given shots, but as long as they have a food source, the whole litter is usually raised healthy. Not always, but more often than not.

Hybrid Vigor in a beagle, what you're referring to, is linebred or inbred dogs are bred for certain traits. Over several breedings, the bad traits are concentrated along with the good traits (they may become loose or tight mouthed, the pups may start getting smaller, etc.). An outcross in this situation brings a new line of those traits, which hopefully will override the poor traits built up as a result of the linebreeding. These traits are there, whether someone tells you that they've "bred them out" or not. What you're hoping, and is often the case, is that the poor traits become recessive to the dominate traits of the new cross. The Hybrid SHOULD be more healthy and the more important traits should become more dominate if the cross is selected correctly.

Clear as Mud?

[bwe007]

hybrid vigor in domestic dogs is a complete falsehood. not only does it not exist in outcrosses. it doesn't even exist in seperate breeds. examples include labradoodles, puggles, yorki-poos, muts, etc. unless you are crossing wolves to domestic dogs you're not going to get any such thing as hybrid vigor. this is not my opinion but cold hard facts.

[hookset]

this is not my opinion but cold hard facts.

Not to be rude... but I'm calling B.S.

[Dr. Chris]

Yes, a better word for it is “Heterosis”.

Heterosis, or hybrid vigor or outbreeding enhancement, is the increased function of any biological quality in a hybrid offspring. It is the occurrence of a genetically superior offspring from mixing the genes of its parents.

Hybrid vigor refers to the increased hardiness and other desirable qualities arising from the crossbreeding of genetically different animals, especially breeding those that have been inbred each within their own line, together. For several years now the benefits of hybridization are well documented in many areas relating to livestock and agriculture.

In the dog world, however, hybrid vigor is debated and challenged, particularly by show breeders. “The myth of Hybrid Vigor” and a few more articles have been written and circulated among “thoroughbred breeders” to discourage the breeding of “different breeds” in order to create a new breed. Such as the Labrador and Poodle to create the “Labradoodle” or the Beagle and Pug to create the “Puggle”...etc... It has financially “hurt” the thoroughbred dog business, especially now that the AKC is starting to recognize many of these breeds. But they can’t change science or what many have been doing for years.

When you examine the history of domesticated dogs, specific breeds were the eventual result of mated pairs of dogs with desirable traits or lack undesirable of traits. When the desired dog is attained, it became the breed. A hybrid dog, commonly called a crossbreed or crossbred in the breeding of animals, is taking this process a step a further by breeding two purebred dog breeds together. But the same can be accomplished within the same “breed” if they are from two totally different unrelated “bloodlines”. The resulting offspring often results in a healthier, stronger animal with desired traits. This effect is called Hybrid Vigor, or called heterosis, which is increased vigor or other superior qualities arising from the crossbreeding of genetically different animals.

“Heterosis” is the opposite of “inbreeding depression”, which occurs with increasing homozygosity. The problem is that it can be a two edged sword, particularly in terms of the selective breeding of domestic animals. When a hybrid is seen to be superior to its parents, this is known as hybrid vigor. When the opposite happens, and a hybrid inherits traits from its parents that makes it unfit for survival, the result is referred to as “outbreeding depression”. Typical examples of this are crosses between wild and hatchery fish that cannot adapt in wild settings. Also, the cross of a domesticated dog with a wolf that does not have the “wild instinct” to survive in the wild. This is only an issue between domesticated and wild animals.

The concept of heterosis is also applied in the production of commercial livestock. In cattle, hybrids between Black Angus and Hereford produce a hybrid known as a "Black Baldy". In swine, "blue butts" are produced by the cross of Hampshire and Yorkshire. Other, more exotic hybrids such as "beefalo" are also used for specialty markets. Within poultry, sex-linked genes have been used to create hybrids in which males and females can be sorted at one day old by color. Specific genes used for this are genes for barring and wing feather growth. Crosses of this sort create what are sold as Black Sex-links, Red Sex-links, and various other crosses that are known by trade names. Commercial broilers are produced by crossing different strains of White Rocks and White Cornish, the Cornish providing a large frame and the Rocks providing the fast rate of gain. The hybrid vigor produced allows the production of uniform birds with a marketable carcass at 6–9 weeks of age. Likewise, hybrids between different strains of White Leghorn are used to produce laying flocks that provide the majority white eggs for sale in the United States.

Hybrid Vigor is very real, it does and can work and has been used for years in dogs, Hybrid livestock and even agriculturally in hybrid corn etc...

[bwe007]

In biology, hybrid has three meanings.
-The first meaning is either the offspring of two different species, or of two different genera.
-The second meaning of "hybrid" is crosses between populations or cultivars ("cultivated varieties") of a single species. This second meaning is often used in plant breeding.
-The third meaning is in molecular biology.

if my understanding is right and all dogs are of the same species how can they have hybrid vigor if they are not hybrids like mules, ligers, etc.

[hookset]

When lines of beagles become so specialized, you are basically getting different "strains of beagles". Northern harehounds, southern beagles, Patch bloodlines, specialty beagles (miniatures, dwarfs, etc.). They have been bred to a specific purpose. Technically, an "outcross" may be a more exact term, but the hybrid theories still apply. Whether the outcross comes back to bite you or not can only be seen after the breeding. I know of several hunters who have crossed a good line of beagles with miniatures (bred to be lapdogs) trying to get smaller dogs. I didn't agree with what they were doing because I believe that hunting stock should be bred to hunting stock. They were happy with the results, I wouldn't have fed them. In that reguard, the definition of "vigor" may have been stretched, but to them they achieved the desired results.

[Boilermaker]

I'm not familiar enough to speak about dogs yet, but you can see hybrid vigor in corn. When a male strain (tassled) is crossed with a female strain (detassled), the result is a plant that grows much taller and has a much larger ear than either of the parents ever were. I can see how this could happen with beagles when two distinctly different lines are crossed.