preventing inbreeding

krystal

Arachnodite
Old Timer
Joined
Jul 18, 2002
Messages
381
with thousands of spiderlings hatching from eggsacs, and with those thousands of spiderlings being sold / traded / given away, i was wondering how you breeders out there make sure your female isn't mating with her brother who has been kept in cooler temperatures (thus slowing his growth speed to inadvertantly match a female), or if your male isn't drumming outside his sister's burrow (because she was kept at warmer temps to speed her growth rate up). is it just a luck of the draw situation? or is there really that much of a difference between the rate in which a male and female mature (regardless of temp, etc)?

to clear up the simple stuff: i know males grow faster than females, therefore they mature faster. i'm also aware that the male doesn't have long to live after his final maturing moult. in addition, elements such as temp, etc... contribute to the speed in which males and females grow. just wanted to clear this up because i didn't want any posts saying, "inbreeding is impossible because male brothers die before the female sisters mature" or something. unless, of course, that is the end-all truth.
 

safetypinup

Arachnosquire
Old Timer
Joined
Feb 17, 2003
Messages
118
Inbreeding is definitely possible, and unfortunately sometimes it occurs regardless of the breeder's best efforts to prevent it. In a sibling-to-sibling mating, many times there is a low hatch rate, and often spiderlings are born "inferior" and die well before maturity. However, in some cases, none of this is evident for some reason, and these "inbred" babies thrive and grow normally. Statistically speaking, inbreeding *must* occur in the wild with varying frequency, despite nature's efforts to keep it from happening, so, unless a breeder can be supplied with meticulous data on both parents, it is a "luck of the draw" situation in many cases.
Hope this was the information you were looking for. Let me know if you need more info. :)
 

jezzy607

Arachnodemon
Old Timer
Joined
Dec 29, 2002
Messages
707
If I was to worry about inbreeding, I would think son X mother is more likely to occur than brother X sister. But, at least the son only shares 50% of his genes with his mother, assuming the mother was outbred with the father. I hope that made sense.
 

Wade

Arachnoking
Old Timer
Joined
Aug 16, 2002
Messages
2,933
I often wonder if the apparent "failure to thrive" syndrome seen in inbred spiderlings may be a result of breeding females at too young of an age. Smaller-sized females may simply be unable to provide the nutrients to developing eggs, resulting in inferior offspring. In order to successfully breed sibling to sibling, females may be being bred at an earlier stage than they normally would. It's possible that in the wild these females would skip until after the next molt, but when confronted with a male in close quaters (a cage) they can be induced to mate. If the keeper carefully manipulates the temps so males mature much slower, he/she may be able to compensate for this effect.

This is just speculation, and I'm not trying to suggest inbreeding is a good idea. The only time it should really be considered is if a species is in danger from dissapearing from the hobby alltogether. I suspect many of the spiders in the hobby now are from inbred, but apparently healthy, stock ( A. geniculata anyone?). Also, if new ones like P. metallica are to become established in captivity, inbreeding will likley be nesessary.

Wade
 
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