Strange question about inbreeding

ustwoandthekids

Member
5 Year Member
Joined
Dec 22, 2012
Messages
141
Bit of a strange question but do tortoises have to be non related to breed like other animals? (Not something I'm planning on doing just wondering)
 

ustwoandthekids

Member
5 Year Member
Joined
Dec 22, 2012
Messages
141
But would the babies have problems like other animals do like deformities etc? Reason I wondered was round my area there is not many different breeders that sell the same species and as many people buy pairs so chance of interbreeding
 

russian/sulcata/tortoise

Well-Known Member
5 Year Member
Joined
Aug 6, 2014
Messages
8,458
Location (City and/or State)
Northern California, bay area
But would the babies have problems like other animals do like deformities etc? Reason I wondered was round my area there is not many different breeders that sell the same species and as many people buy pairs so chance of interbreeding
i think it takes a couple of generations of inbreeding to create any real problems.
 

Tom

The Dog Trainer
10 Year Member!
Platinum Tortoise Club
Joined
Jan 9, 2010
Messages
63,439
Location (City and/or State)
Southern California
It would take more generations for there to be problems than it would for mammals.

And btw, tortoises should not be housed in pairs.
 

Yvonne G

Old Timer
TFO Admin
10 Year Member!
Platinum Tortoise Club
Joined
Jan 23, 2008
Messages
93,432
Location (City and/or State)
Clovis, CA
Inbreeding doesn't cause deformities. What it does is strengthen any poor qualities running in the line. So if your tortoise has a tendency to have knock knees and you breed him to his sister, the resultant babies will have more of a chance of having knock knees. Inbreeding enhances the chances of certain weakness that might be present.
 

G-stars

Well-Known Member
5 Year Member
Joined
Jul 11, 2014
Messages
1,889
Location (City and/or State)
Southern California
It would take more generations for there to be problems than it would for mammals.

And btw, tortoises should not be housed in pairs.

Can you explain why it would take more generations for tortoises than mammals?
 

Tom

The Dog Trainer
10 Year Member!
Platinum Tortoise Club
Joined
Jan 9, 2010
Messages
63,439
Location (City and/or State)
Southern California
Can you explain why it would take more generations for tortoises than mammals?

Nope. Just what I was taught by professors who know a lot more than I do. They explained it well, but those details escape my ever aging mind. I'm sure it would be easy to research and find more solid info.

Just for fun, it would take even longer to see any issues from inbred insects, like roaches. I recall the statistic that it would take 99 generations, or more, to see any sort of genetic abnormalities from a single pair of roaches. Add a third roach of either sex and it jumps to 999 generations or more. I can't back any of this with scientific citations. As I said, its just what I remember from school so many years ago.
 

ustwoandthekids

Member
5 Year Member
Joined
Dec 22, 2012
Messages
141
I personally wouldnt keep in pairs anyway but often see them for sale as babies in pairs!! I have 4 different species of tortoises all kept separate but was just something I've always wondered
 

G-stars

Well-Known Member
5 Year Member
Joined
Jul 11, 2014
Messages
1,889
Location (City and/or State)
Southern California
Nope. Just what I was taught by professors who know a lot more than I do. They explained it well, but those details escape my ever aging mind. I'm sure it would be easy to research and find more solid info.

Just for fun, it would take even longer to see any issues from inbred insects, like roaches. I recall the statistic that it would take 99 generations, or more, to see any sort of genetic abnormalities from a single pair of roaches. Add a third roach of either sex and it jumps to 999 generations or more. I can't back any of this with scientific citations. As I said, its just what I remember from school so many years ago.

Interesting. I wonder if that's a reptile thing and not exclusive to tortoises.
 

G-stars

Well-Known Member
5 Year Member
Joined
Jul 11, 2014
Messages
1,889
Location (City and/or State)
Southern California
So I looked around and found that mammals tend to travel further to mate. While reptiles can handle and cope better with inbreeding because they don't travel as far and the same with insects.
 

Tom

The Dog Trainer
10 Year Member!
Platinum Tortoise Club
Joined
Jan 9, 2010
Messages
63,439
Location (City and/or State)
Southern California
So I looked around and found that mammals tend to travel further to mate. While reptiles can handle and cope better with inbreeding because they don't travel as far and the same with insects.

The explanation I got had to to with the simplicity of their DNA in comparison to the complexity of mammal DNA. It was not based on proximity to potential mates.

I would love for someone with a correct understanding of these things to come along and explain it well for us all.
 

G-stars

Well-Known Member
5 Year Member
Joined
Jul 11, 2014
Messages
1,889
Location (City and/or State)
Southern California
Yes I read that too. From what I understood reptile's and insect's DNA isn't as complicated as mammals DNA. Part of that was because of how much older reptiles and insects are compared to mammals. Some of the oldest living creatures on earth have the simplest DNA makeup.
 

N2TORTS

Well-Known Member
5 Year Member
Joined
Feb 21, 2010
Messages
8,803
I know there are lots of opinions on this but…………Look at Locality Island animals ...talk about inbreeding?
Inbreeding increases the chances of recessive traits being expressed. If no deleterious ones are carried (entire pop. is homozygous for a trait, or the recessive trait does not affect the animal adversely) inbreeding has little effect...look at lab mice and guppies for example.
Deleterious genes are typically rare in populations, especially lethal ones. The idea that inbreeding will automatically lead to some gross defect is misleading. Certainly the risk is increased but the possibility is still small. Poor nutritional or environmental conditions can also be enhanced as risk factors when paired with a line bred mutation. Does anyone really believe that the only role melanin plays in the body is to create dark pigmentation in the skin? Mutations that disrupt metabolic pathways (such as amelanism) can potentially lead to other developmental outcomes aside from the obvious ones we see and are breeding for.

Genetics 101 simply= that the first result of inbreeding is inbreeding depression or the lowered fitness of individuals within a population. A lot of inbreeding depression is masked by captive conditions where animals do not face the rigors of the wild. Further, we create our own form of inbreeding depression by ensuring that all animals in a clutch or litter survive to reproduce. In the wild, typically 90% or greater would die in the first season, removing the weaker genes. This has been well proved and established in other stocks of animals, fish for example- in fish hatcheries where salmon and steelhead raised in raceways have a lowered fitness even 2 generations out. I really don't think inbreeding affects the animal other than producing some interesting morphological traits. Although with tortoises this is a long journey to prove out with the first 7-10 years –just reaching a young breed able adult in the Redfoot world.
Inbreeding can and is mostly done to bring out certain traits that aren't normally expressed in a population, or to combine certain traits which make them more desirable in the hobby. With some species/forms, new specimens just aren't available.
Another good analogy “Population structure and Inbreeding from pedigree analysis of purebred dogs”
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2390636/

In my own Hypo program and 10 years later .....I have yet not inbred any of my animals , simply for the fact I don't need to prove out any recessive gene I'm looking for. (why you see variance between the 3 adult Hypos .....all non related ) I have only kept 2 out of the many Hypo's hatched here at the Cove' ......and a good 10 years down the line to see if "that" particular gene proves out .
 
Last edited:

ZEROPILOT

REDFOOT WRANGLER
Moderator
Tortoise Club
5 Year Member
Platinum Tortoise Club
Joined
Jul 16, 2014
Messages
29,068
Location (City and/or State)
South Eastern Florida (U.S.A.)/Rock Hill S.C.
Great question...And one that I could NOT answer. None of my torts are related, but it would have bothered me to interbreed. The cast of the movie DELIVERANCE comes to mind with tiny fiddle playing tortoises. Frightening.
 
Last edited:

New Posts

Top