Pokie inbreeding?

Jacobchinarian

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Aug 2, 2010
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I know with most spieces it will result in horrible defects but since they live communally sometime does that mean that it is ok for pokies to inbread.
 

Philth

N.Y.H.C.
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LMAO!!!!!

This thread will self distruct in.. 3...2...

PIG-
haha, I'll take the bait....

I'd say alot of sp. in the hobby are inbred, with little side affects.

Later, Tom
 

JimM

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I don't know of any hard data demonstrating that repeated inbreeding will not result in problems.

Personally, if mom and dad were not related, I'd do it for one generation.
After that I'd bring in new blood.
 

Scorpendra

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The thing about inbreeding is that it's more likely that certain (otherwise hidden) traits will be expressed, since both parents have a copy of that specific gene to pass on to offspring. It becomes bad when these traits could lead to a disease or some malformation. This is why purebred dogs are a huge mess.

I doubt the effect of this on arthropods is documented too well....as with many other things. But I have a gut feeling it's more of a concern for vertebrates.
 
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syndicate

Arachnoemperor
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I know with most spieces it will result in horrible defects but since they live communally sometime does that mean that it is ok for pokies to inbread.
Any sources for where spiders inbred have resulted in horrible defects?I know of none!I also know for a fact that a large portion of captive bred spiders in the hobby are often frequently inbred and completely healthy ;]
-Chris
 

MichiganReptiles

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I agree that there is probably quite a bit of this going on in the hobby already. For example, I bought my male and female G. pulchra from two different people and found out later they are sac mates.
 

JimM

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Any sources for where spiders inbred have resulted in horrible defects?I know of none!I also know for a fact that a large portion of captive bred spiders in the hobby are often frequently inbred and completely healthy ;]
-Chris
There are plenty of sources documenting defects in other genera. I know that with fish you may not see any health issues, but color starts to suffer as soon as F2. We know inbreeding theraphosids causes no easily detectable or visible defects to a certain point. What about 10 generations down the line? 15? 20?

I don't know that anyone has done the work. It's logical (and safe) however to conclude that sooner or later you'll run into problems. SO, I think it's best to er on the side of caution and avoid inbreeding when possible/ practical. That way if someone gets some slings from you, and they breed, then it's the first time. (unless your separate sources can be traced back to the same lineage, something that happens enough)

Bottom line, IMHO, they should only be inbred out of necessity, (while working hard to find new blood) rather than plain laziness, which happens often enough.

Find a NICE female, find a brilliant male of differing bloodline - those are the T's you breed.
 

WARPIG

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The problem we as hobbyists run into is that our breeding stock is limited at best. What I raise here in NJ may be the relative of a MM I get two years down the road from across the country to mate with her.

New blood, how can we tell???

IMO inbreeding will, over time hurt the blood lines.

PIG-
 

syndicate

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defects to a certain point. What about 10 generations down the line? 15? 20?
I'd say there's most likely quite a few species present in the hobby that have been inbred 10-15 generations by now with no signs of defects ;]
I also wouldn't be surprised if inbreeding occurs in the wild.
-Chris
 

JimM

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The problem we as hobbyists run into is that our breeding stock is limited at best. What I raise here in NJ may be the relative of a MM I get two years down the road from across the country to mate with her.
Yep - I've tried to trace blood, it get's difficult very quickly.
 

JimM

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I'd say there's most likely quite a few species present in the hobby that have been inbred 10-15 generations by now with no signs of defects ;]
I also wouldn't be surprised if inbreeding occurs in the wild.
-Chris
I'm positive inbreeding happens in the wild, but that's different from line breeding for multiple generations with no new blood. :)

You may be right about the 10-15 generations thing too Chris - who knows.
As well you may be completely right about it having zero effect, I have no idea.

You also might take one of those "F15" tarantulas and be shocked at how much larger, or more colorful a wild individual looks next to it. Who's to say that one original female wasn't on the small side, or on the drab side..or had less blue than some other examples from the same locale?

Maybe when making sure (as best you can) that you're not inbreeding, all you're doing is making yourself feel like you're doing a better job. Maybe you're actually doing some good. I can't make a claim that I know the answer to that. BUT, I do know what I see in other genera.

I just think it's better to err towards the latter just in case. :)
 

Enki40

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"The Tarantula Keeper's Guide" - Revised Edition
Pages 295 & 296


Pedigrees And Inbreeding

"We simply do not know what effects inbreeding will have on a population of tarantulas. We do know that other, more familiar animals like dogs and tropical fish cannot be inbred to any large degree before serious defects become obvious and the population eventually loses its vigor and ability to breed at all. The population geneticist explains this by saying that this reduces the genetic variability below a critical level.

There is at least one hint that tarantulas are little different from other animals in this respect, however. In 1998, Mr. Rick C. West related the results of experiments in inbreeding two species of tarantulas (a Phlogiellus species from western Malaysia and Grammostola iheringi from northern Argentina) in a posting to an Internet arachnid forum. In both species, inbreeding caused severe deformities, difficulty molting, and reduced size after only one or two generations. Based on his experiences, we may safely say that inbreeding is to be strictly avoided except in the most extreme circumstances.

Others have pointed out, however, that many insects and other creatures reproduce parthenogenetically generation after generation with no apparent adverse effects. In this case, the genetic variability is reduced to zero in the population, and the species seems to survive, even thrive, anyway.

There are many differences between the two examples given (e.g., vertebrate versus invertebrate, sexual reproduction versus asexual reproduction, the intensity and type of selective culling or natural selection on the populations) that cloud the issue, and their relative importance cannot be properly assessed. For lack of definitive data, these authors assume a very conservative stance and recommend strongly against inbreeding, knowing full well that this opinion will be open to severe debate and possible criticism.

It is beyond the scope of this book to deal fully with the topic of inbreeding, its consequences and remedies. The enthusiast is referred to books on the subject in the genetics, agriculture, and animal-husbandry sections of a university library. We give here only a few basic guidelines.

A pedigree should be maintained for each individual to be used for breeding. This is merely an itemization of the tarantula's ancestry, if known, and a list of the individuals with which it has mated and produced offspring.

Under no circumstances should any individual tarantula be allowed to mate with any relative closer than second cousin (defined as the children of the children of their aunts or uncles). Periodic attempts should be made to breed the members of one breeding stock with completely unrelated members from the stock of another enthusiast. Ideally, the other enthusiast will also be maintaining pedigrees and be able to verify that the individuals in question are not closely related. This is particularly important as the tarantula-breeding hobby develops and the web of crossbreeding becomes more complex.

These rules may be violated under extreme circumstances. One such case might be where an enthusiast possesses the only surviving captive individuals of an extremely rare species, perhaps all being siblings from one or a very few eggsacs. This situation is probably a lot more common in captive-bred tarantulas as than most enthusiasts appreciate. Especially in this case, every effort must be made to secure additional, unrelated breeding stock.

Another case where limited inbreeding might be allowable, if not advantageous, is the circumstance where a hobbyist is attempting to develop a hereditary line of tarantulas that displayed certain desirable features such as a remarkable color pattern, the absence of urticating bristles, or excessive size. The human race has done this innumerable times with other domestic animals and as the hobby progresses there is no reason to doubt that we will do it with tarantulas as well."
 

Spiral_Stairs

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I was always under the impression that nature sort of had its own built defense against inbreeding in tarantulas. And that was simply that the males always grow and mature significantly faster than the females do. So how is it possible for inbreeding to occur in the first place?
 

captmarga

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Studying equine (horse/donkey/mule) genetics, I am always doing research on breeding. In spiders, I would think you would see a greater number of bad eggs, and some malformed adults. Bad genetics (deadly recessives) do try and take out the embryo first.

With parthenogenic reproduction, you are literally talking about clones, so you don't have additional recessive traits entering the picture. As long as the base female has a good gene set, her daughters will as well. It's not really even inbreeding at that point, it's truly cloning.

I agree, try and introduce outside if at all possible, for as long as possible. If it's a rare species, there is going to be some inbreeding in the captive population.

In the donkey pedigree world, we tell people they should NOT in-breed unless they know for certain it hasn't been done in the last 5 generations. This can't be certain if there isn't a written pedigree to fall back on. With a pedigree, you can look and see all the crosses, without, you have no idea if three generations back there was not a father/daughter mating on the top side and again on the bottom side. I *have* seen a real donkey pedigree that had zero male diversity in the entire pedigree. Consanguinity at it's worst.

I won't be breeding any of my spiders unless I get a rarity, and then I will try and record who they come from. Time for pedigree programs for T's?

Marga
 

Lorum

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I was always under the impression that nature sort of had its own built defense against inbreeding in tarantulas. And that was simply that the males always grow and mature significantly faster than the females do. So how is it possible for inbreeding to occur in the first place?
Well, that is completely false. Females can grow and mature faster than males, and they can be mated with their brothers (sac mates). Of course, that doesn't mean we should do it.

Even if it were true that some males tend to mature faster than females (I don't certainly know how much of this is true, and if it applies only to certain species or it's general; I would be very pleased if I could read a scientific article about it), you can "control" their grow-rate. It depends on feeding regime and temperature, more than anything (IMO).
 
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tanalos

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Sep 4, 2010
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Pokie inbreeding

Ok I'm sold!
I want to submit a grant to the government for a 5-year executive study on breeding Pokies. Part of the grant obviously goes to my research on the perfect beer, pizza, movie combination (which I did with ROTC scholarship) but being paid to study and breed Pokies....think about it {D
 
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