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Post by Deleted on Jan 30, 2012 10:29:37 GMT -5
Even if you know what you're doing with breeding domestic ferrets, there is still guesswork when pairing mates- Ferrets are bred young (before their genetics are fully "played out and breeders do not have the option to genetically test their ferrets prior to breeding.
Last I heard(years ago at the IFC symposium "Forum at the Fort"), the Black-footed ferret reintroduction effort was initiated with a single breeding pair. The initial breeding pair and all offspring have been fully genetically mapped. All this information is kept in a database, and all breedings are fully analyzed in advance of any mating. AT the time of the Symposium, there was only one known genetic mutation introduced into the population - I cannot recall the nature of the mutation, but it was completely irrelevant to the health/longevity of the species. Things may have changed since I attended the symposium, but it's encouraging to see the care that has gone into the BFF reintroduction program.
The bottom line on all this is that either accurate genetic mapping and natural selection are the only "fail-safe" breeding "controls" we have. That leaves a LOT of guesswork and tracking of all off-spring over generations of breedings to understand the quality of a genetic line. All too often, high demand for the offspring of a big show-winner results in the spread of a bad gene to the lines of many other breeders. Outcrossing/inbreeding/line breeding can all introduce problems.
Again, breeding to establish a "clean" genetic line is extremely difficult, even with genetic mapping. Without genetic mapping, breeding requires a LOT of time and patience to "prove out" a genetic line- it take generations of breedings, tracking the health status/cause of death, etc. of all offspring).....As I've always said, "there are NO guarantees".
-jennifer
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Post by Deleted on Jan 30, 2012 12:27:53 GMT -5
Well said. Thanks for that Jennifer
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Post by Deleted on Feb 8, 2012 1:41:36 GMT -5
This is an incredibly intelligent thread and forum. I love it. Thank you all. "Breeding" has a bit of ill-favor here in the states because of the 'melting pot' mindset and social education along those lines. That said, I love that the necessity for care and consideration of which traits need to be kept and which ones should be weeded out by proper breeding, has been so well and truly expressed here. You cannot get rid of these terrible birth defects and congenital traits (extra legs, parts, etc) without knowing that they do/do not exist in the pairs that you mate. These traits have to be isolated in the critters (breeding stock) that you have so that those 'bad' genes can't be passed on. It's just how it works. Mother Nature does the same thing by killing the critters that can't survive. I hope I haven't killed, beat, and made into Alpo this particular horse.
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Post by Deleted on Feb 8, 2012 9:11:35 GMT -5
I'm just curious as to the effect of inbreeding in ferrets are? I know amongst various other species, inbreeding to some extent can be beneficial & in others it can be quite a lethal practice. I've read quite a lot on the topic in other species as such, but haven't been able to find anything that is particularly informational. I'm no scientist, biologist, vet etc. I'm just a phlebotomist (for humans) with a lot of time on my hands. When I'm bored at work I love to read/browse the Ferret Genetics group on Yahoo and the Ferret Health List (also on yahoo) you would probably really enjoy those. From my reading inbreeding can cause dwarfism, intellectual set backs annd if I understand correctly, Angora ferrets came from inbreeding as well (correct me if I'm wrong, guys) as for benefits, I know of none. As I said I love the previously mentioned sites and I bet you would too, I'm sure I'm forgetting things (lol) so I definitely recommend you check those out
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Post by Sherry on Feb 8, 2012 11:48:49 GMT -5
I believe angoras were simply a mutation that was encouraged, the same as our fancy colours.
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Post by Heather on Feb 8, 2012 14:38:52 GMT -5
Ahhh, the study of genetics...to line breed, inbreed or outcross...such a dilema Ok, an angora is a ferret without an undercoat. It only has a guard coat. It is a mutation. Colour variations are a mutation but different colour variations are different mutations. "In the embryo melanoblasts, the precursors of pigment cells (melanocytes) arise in the neural crest and migrate to their destination (do we see a problem here...think about it). Normally, they are able to reach all parts of the body and the skin will receive it's full complement of pigment cells. Pigment cells produce pigment by a complex chain of chemical reactions. The pigment in these cells is confined to organelles called melanosomes. The melanosomes are transformed into growing hair to give it colour. Mutations can affect the migration of these melanosomes". (the Coat Colour Book, the genetics of coat colouration in the domestic ferret) There are 3 major mechanisms that can effect the pigment process. This is what we call dilutes. This resulting process affects lusosomes...these are found in most cells, especially in leukocytes (white blood cells), liver and kidney cells. This leads to an increased susceptibility to bacterial infections due to an impaired immune system, an increased tendency to bleed due to platelet granule defects, kidney disfunction. Dilute coat colours might be pretty but life is often shorter. Neither of these conditions are caused by line breeding, but by breeding for a specific purpose. Could line breeding be part of the issue possibly but it isn't "the" issue. You could get the same results plus more problems by continually outcrossing....why because you're breeding a mystery every time, except for your purpose. You've no idea as to what you're playing with, except that you're breeding for a coat type and colour. Each one of the "types and colours" comes with it's own genetic mutations because that's what they are. There are only 2 true colours..sable or poley and albino. None of the other colours would survive in the wild if it wasn't for man's interferrance. That part is simple. Does it answer your dilema about breeding coarse...not really that's why it's often a good idea to have a mentor who's been in the process for awhile before throwing two ferrets together. If you continually breed the same line with no outcrossing or fresh blood you will get problems (but you will know what your problems are going to be )If you continually outcross you're going to get problems but you're never going to know where they come from and worse you're never going to know how to get rid of it. ciao
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Post by joan on Feb 9, 2012 13:12:40 GMT -5
Heather, that's an excellent explanation of why the dilute colors have weaker immune systems. You should post that on the Genetics Group and cite your references. Sukie questioned that years ago when I posted to that effect when I could not provide any research to back it up since I only had 30+ years of observation and anecdotal evidence. That also explains why the NCD genetics which are responsible for the vast majority of white marked ferrets (at least in the US) have resulted in serious health problens and shorter lives for so many of these ferrets.
When I decided I wanted to breed ferrets, I chose to bred the medium to dark sables with full pigmentation from a background free of the fancy colors, I did so because I'd seen the genetic defects and health problems in breeds where the genetics of dilute color and the NCD white markings were either not understood or were ignored because the buying public wanted such colors.
I also chose to linebreed and inbreed my original stock so that I would know the genotype of my breeding stock, what problems (if any) were there and who the carriers were so that they could be eliminated. When I brought in an outcross several years later, I then did close breedings with the offspring for the same reason.
As Heather pointed out, continual outcrossing makes it impossible to know where the resulting genetic and health problems are coming from as it spreads the genetics of all the problems throughout the breeding population until two carriers are mated. By that time, it's likely that 80% or better have those genetics and it will be next to impossible to breed them out.
It's bad enough when only one genetic problem or disease is involved, but far worse when there are multiple problems which most or all of the breeding stock carry. At the present time, ferrets have adrenal disease, insulinoma, early and late onset lymphoma, various types of cardio disease, and kidney disease to be concerned about. If the carriers of the genetics which result in these diseases were removed from further breeding by the commercial and private breeders (which will never happen), there would most likely no dilute or white marked ferrets left to breed from.
It isn't even a question any more whether these fancy colored ferrets will develop one or more of these diseases. It's now a matter of which one(s), how early, and how long they can be kept alive after the disease(s) develops. Ferrets should live at least 7-10 HEALTHY years, and most sables and albinos from backgrounds free of the fancy colors do so. As the deleterious genetics of the fancy colors are doubled and redoubled on, their life spans have become shorter as they develop these diseases at increasingly early ages...and ferrets have developed the reputation of a very expensive pet to keep due to their high medical costs.
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Post by Deleted on Feb 9, 2012 13:46:24 GMT -5
Very interesting posts!
I have a question - my girl Trixie is a champagne. I thought I read somewhere that champagnes resulted from a cross of albino and sable (Trixie has ruby eyes, so this made sense). Trixie has always been very healthy, she's rarely gotten sick. Are dilutes that result from albino x sable also at risk for the same health issues?
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Post by joan on Feb 9, 2012 14:11:34 GMT -5
The champagne (sandy in the UK) is thought to be a double dilute of sable. Since she has ruby eyes, she very likely has the genetics associated with the dilute colors. What she develops, and when, will depend on the genetics of her background.
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Post by miamiferret2 on Feb 9, 2012 14:19:32 GMT -5
very interesting post. i love reading about these things. where is this genetics forum? i was on one that they have on yahoo but it was really hard to search posts in there.
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Post by joan on Feb 9, 2012 15:27:06 GMT -5
It's the Yahoo Genetics group that I was referring to. It's rather inactive most of the time, as most of the breeders got tired of Sukie's nonsense. I still post occasionally when she irritates me more than usual.
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Post by Sherry on Feb 9, 2012 17:03:42 GMT -5
Those would be interesting to read ;D !
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Post by miamiferret2 on Feb 9, 2012 20:56:17 GMT -5
Oh yes. That is the one I have been on. She tends to annoy a lot of folks. I call her the "raw meat police." LOL
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Post by Heather on Feb 9, 2012 21:24:01 GMT -5
I joined because I wanted to learn more.....but it's so inactive ciao
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Post by nancyl on Feb 10, 2012 12:59:04 GMT -5
Oh yes. That is the one I have been on. She tends to annoy a lot of folks. I call her the "raw meat police." LOL Ha! I just call her the flaming loon. It would be funny but she's actually dangerous if anyone listens to her.
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