Genetics and Breeding

[rustie]

Ive decided to breed my corns. first things first. i definatly have a male and a female, but i have a snow i bought 2 years ago as a female. I took her to a local pet shop, they said shes a he by looking at the length of the tail. after a little reasearch im not sure tail LENGTH is a tell tail sign. the mail amery motley i bought with the snow is noticably larger and more docile. so... is there a positive way to id them with out probing, and where can i get them probed. im in orlando fl if anyone know someone relyable.

next issue. ok so i understand some basic genetics. snows are amel and anery double expressed recessive traits. but i heard that motley is a dominate trait. is it? and if so is it autosomal dominant leathal? are there any autosomal lethal traits in corns? (autosomal dominant leathal is how achrondoplasia (dwarfism) is in humans... 2 dwarfs (Aa) have a 25% chance of AA which is leathal, 50% Aa dwarf, and 25% aa avg human. ) i dont quite understand hypo's, butters, bloods,... or what ever else is out there (i only know about what i own... it pertains to me so i remembered). could someone give a rundown on the genetics if they could.

last issue i promise. ive kept the males and females seperate. how should i go about breeding them? do i need to be there? oh i have a 100+ gallon tank i crafted. it has a sliding plexyglass door and the rest of it is wooden. the males share it and the females have a 20 long, but i plan on partitioning the 100+ in half. top and bottom. i guess one side will be for breeding. i live in FL and was wondering since there really arnt but a week of winter if cooling them here is important.

well, any advice you experienced breeders or geneticists can provide will be exteremly usefull. btw im taking genetics this fall at UCF. im looking to get some bonus between the corns and the rats i breed to feed them. thanks for the help.

[nuno]

Hi rustie, I would like to say who ever told you that your snake is a male by the length of the tail doesn't know what they're talking about. There are two ways to tell and that's popping and probing.

From what I understand Motley is a co-dominant trait.

The breeding process is left up to the snake, I don't think you need to be there. Breeding season in captivity occurs after a 2 - 3 month hibernation period (winter) at temperatures of 45 - 55F. Animals should be in excellent condition. You put a male and female adults apoximately the same size in the enclosure and they'll do the work. You should check up on them from time to time.

funny I can tell all my corns sex
by their tail shape (not length)

[Kyle Walkinshaw]

Gender can be determined by tail length AND width, aswell as what Nuno mentioned, probing and popping. Popping adult corns or any adult snake for that matter is rather difficult as they have much stronger muscles which they use to hold in the hemipenses (sp?). It is much easier to pop babies and just record the gender and keep them seperate.

[drewlowe]

nuno I'm not quite sure if brumation is a absoulute must. And my corns were sexed at a week old by tail length and width by an expericed breeder (over 20 years) and he was correct.
I didn't really lower my corns temps i just lowered their day and night time lights (photosynthisis) from 14 hours day 10 hours night time. to 10 hours day and 14 hours night. for 2 months with gradual change in the day to night hours.
Mine have breed succefully this year. I don't know exactly though so i may be wrong and mine just got lucky this year. I only keep one breeding pair so i'm not real big into corns.

As far as genetics and sexing though, i know i cant help. So i wont even attempt. But good luck with breeding.

[vanderkm]

As others have said, it is late this season to attempt breeding and sexing adult corns can be done by tail shape, but probing is definately the best way to go in my experience, since examining the tail requires experience and can still be wrong, as can popping (if the hemipenes pop out you can be sure it is a boy, but if not - it could be a girl, or a boy that didn't pop).

On the genetics, I don't believe there are any autosomal dominant lethal genes in corns. Motley and stripe are related, and may be different alleles on the same site but both are recessive to normal (saddle) pattern, I don't believe either has been shown to be dominant. The expression of these traits seems to vary considerably with heterozygous (stripe het motley or the other way around) animals that can look as if they were striped. Still a lot to be worked out with that gene.

Bloodred is reported as polygenic, with some reflection of the characteristics in crosses to normals and a lot of variability. It was associated with reduced viability but most of that has been bred out.

Hypo was easy to explain as a straightforward recessive that reduced the intensity of black pigment, until it became apparent that there were more than one type of hypo, as there are two types of anerythristic.

Butter is the easiest of what you have asked about to explain. It is homozygous caramel gene combined with homozygous amelanistic. The caramel gene showes enhanced yellow when homozygous, and produces caramel corns (when amel gene is normal) and amber corns when combined with homozygous hypo gene.

Check out http://serpwidgets.com/cornsnakes/morphs/morphs.html or http://www.serpenco.com/ for more info on genetics or photos of corn morphs.

Good luck with your breeding plans for next year.


mary v.

[rustie]

Originally posted by reverendsterlin
funny I can tell all my corns sex
by their tail shape (not length)

if i post good pics of their vents and lower u think u could look and take a stab a sexing them?