Genetically defective?

[DuxorW]

Dux, can you address the difference between deformities that are genetic as opposed to developmental? Would the one-eyed baby be more likely to be one or the other?

It's hard to say. If they made one eye correctly then they clearly have a functioning pathway for making eyes. If the eye is in the middle of the head, called cyclopia, that can have genetic and environmental causes.

Kinked vertebrae can also be genetic or environmental. The formation of regularly sized and shaped vertebrae is reliant on a molecular clock that determines the rate of formation of structures called somites that will give rise to the vertebrae. This clock is sensitive to temperature during development.

 

[DuxorW]

(I am thinking a sporadic kink is usually not genetic but it does seem more common in lavenders)

 

[DuxorW]

So right what I'm gathering is that:

a- I can sell the babies, full disclosure of course.
b- I should remove the dam as a breeder. (no one recommended this but I get the feeling it would be a good idea)

Maybe mate the dame to a different male?

 

[fyrefocks]

Maybe mate the dame to a different male?

Works for me. I have a completely unrelated caramel stripe male that will work.

 

[DuxorW]

Also- on a side note- I would LOVE to see someone test breed an above-the-vent kink to a non-related same, and document the results. I am not convinced that kinking is genetic, as opposed to developmental or incubation-induced (if that is different).

I have a male orchid with a kink that I am not worried about breeding. I am aware of at least two genes in mice that increase the odds of sporadic vertebral defects but do not directly cause them. Lavender could be such a gene in snakes.

 

[HerpsOfNM]

DuxorW, since I have you here, can you also tell me why Murphy chose to give me no amel based babies when both parents are het amel?

Granted a small sample set, but the same reason I didn't nail a butter tessera, stripe tessera, caramel striped tessera, or butter stripe tessera last year when I paired a tessera het butter stripe to a butter stripe. I only got 3 eggs and definitely can't complain about getting a caramel (which unfortunately died), butter stripe (that I'm still not convinced isn't tessera), and a caramel tessera (the ever photogenic Thor).

This year my sample set is 10 eggs, so it'll be 1 caramel tessera and 9 normal corns with my luck. :awcrap: 6-7 days until I find out.

On a different note, for this season I paired above said male tessera to a granite (unknown hets) with the result of 12 eggs, 11 fertile. The results: 1 normal tessera, 1 hypo, and 9 normal corns. 1 tessera out of 11 fertile eggs. uke01: But I now know the granite is het hypo, as is my tessera het butter stripe. So I guess that makes him tessera het butter/amber stripe.

 

[HerpsOfNM]

Dux...

what's your take on the environmental attributes tied to genetics, more specifically nutrition?

I know in leopard geckos many have seemed to assume a correlation in lack of vitamin a intake with females to eyelid deformities in offspring, myself included. I definitely know temps (elevated) can greatly influence said deformities. And, IIRC, eyelids and pigment are some of the last developmental steps supposedly within leopard geckos.

 

[DuxorW]

Dux...

what's your take on the environmental attributes tied to genetics, more specifically nutrition?

I know in leopard geckos many have seemed to assume a correlation in lack of vitamin a intake with females to eyelid deformities in offspring, myself included. I definitely know temps (elevated) can greatly influence said deformities. And, IIRC, eyelids and pigment are some of the last developmental steps supposedly within leopard geckos.

I don't know enough about this specifically but it makes sense. Vitamin A derivatives act as signaling molecules during many developmental processes and the embryo is getting its nutrition from the yolk made by the mother, so if she is vitamin A deficient the embryo could be as well. Excessive vitamin A is also a teratogen.

 

[HerpsOfNM]

I'd forgotten about that too. I know hypervitaminosis A can be problematic as it's fat-soluble over water-soluble, like a fair amount of the vitamin b complex (turns your urine neon yellow when in excess).

I know recent pushes (last few years) within the herp community for multivitamins has been to develop and/or include animal-derived vitamin A (retinol?? I think) over beta-carotene (plant derived) for non-herbivore/omnivore species. I know Allen Repashy discusses this with regard to his line of supplements, but I've not thoroughly edjumacated myself on it.

 

[kc261]

I think I've read that incubating at 85 and above results in a higher frequency of kinks and other defects in corns. But, that doesn't mean that incubating at 84 is guaranteed to be safe.

In BPs, there is a morph called caramel albino that has a lot of trouble with kinking. People are reporting better success by incubating the eggs a few degrees lower than BP eggs are normally incubated. Perhaps your female (and possibly her male brother as well) carry a gene that makes the babies slightly more sensitive to the high end of the temp range.

It could also easily be that the 90 degrees cooked the first batch, and the one in the second batch was just one of those occasional deformities that will pop up occasionally no matter what.

I would not hesitate to sell the babies, but I would give full disclosure to the buyers. As a buyer under those circumstances, I would not expect a "long term guarantee" because who knows what might have caused one of those babies to die, and if I made the decision to buy it knowing the situation, well, I should live with the results of that choice. On the other hand, if you start hearing that several of them have issues, then you might want to consider refunds or some other arrangement.

 

[DuxorW]

I wonder if a lower incubation temp would help with lavenders morphs as well?

 

[Nanci]

Worth a try. I typically incubate at 82, but it can range from 80-84. I could set an incubator at 80 or even 78, for lavenders. If I ever dare to go back to lavender again...

 

[HerpsOfNM]

I've avoided lavender because of the known kinking. That avoidance dates back to 2000, when fresh out of high school I worked for a local mom & pop herp store and the owner had a thing for corns. Also same shop that introduced me to John and Briget Bernardi. Shop owner loved lavenders but was super picky on them. When asked, well as many have put it...kinking.

Colubrid keepers such as Joe Forks, Damon Salceies (known more for his locality gray-bands and albino chondro), Brad Alexander, and a few others feel we incubate North American colubrids way too warm (85-88°F). I was one of those that use to incubate my snake eggs at 86-88 and have noticed that those offspring were typically smaller in weight, hatched faster, and more often than not had not absorbed all their yolk at pipping.

I've dialed back and try to keep my temps below 85 now. This was hard to do in NM with evaporative (or swamp) cooling. Here in TX, it seems a tad easier to maintain my overall temps period. House also stays a more constant temp (some attributed to the house being built in 2002) due to the use of AC. My HerpStat ND is set to 82.5°F and is currently running at 0% power on proportional mode, with my igloo coolerbator currently at 84.4°F per my old, trusty radioshack indoor/outdoor thermometer.

I'm rambling...

 

[Nanci]

I use those Repti Pro incubators that cool as well as heat.

 

[nancyg]

(curious look) Are there ever any deformities or problems attributed to incubating eggs at the lower end of the temperature range? Perhaps a temp of the 78-80 degree range?

 

[DuxorW]

Vmsherp says they incubate theirs at 78-80, so I'm guessing not?

 

[Nanci]

DuxorW, since I have you here, can you also tell me why Murphy chose to give me no amel based babies when both parents are het amel?

Gambler's fallacy The tendency to think that future probabilities are altered by past events, when in reality they are unchanged. Results from an erroneous conceptualization of the law of large numbers. For example, "I've flipped heads with this coin five times consecutively, so the chance of tails coming out on the sixth flip is much greater than heads."

Ran across this today, seemed appropriate...

 

[dave partington]

When you punch the hets into the corncalc, the results tell you the possibility of what each egg might produce, not what the results for the entire clutch will be.

The following is personal observations; nothing scientifically proven here:

Be careful giving vitamins to snakes which have never had vitamins. They can live for decades with a deficiency, but when dosed with a vitamin which has been lacking for a long time, they may over-absorb what has been missing, leading to problems worse than being deficient. Err on the safe side. A little very tiny amount is better, if any at all. A dose of calcium for females within a week following breeding does not seem to hurt.

Regarding incubation temperatures, the clutches I've incubated at 76F have taken 11 (+/- 2) weeks to hatch. Babies are huge, 8-13 grams; there is no unused yolk left in the eggshells, color is well developed, feeding response when_not_on_heat is markedly better, -but still there is the occasional DIE. I am extra extra careful to make sure the humidity is a little Lower for 'cooking' long&slow.

This year I am expecting hatchlings in late September through December, around the time when adults go into brumation, which should free up time for working with babies.

 

[Nanci]

Dave, have you noticed a decrease in kinks or other defects, or have you just always used that temp?

I, too, like to have not-so-much humidity.

 

[DuxorW]

In 12 healthy eggs, the odds of getting zero amels and all normals is around 3%. Think of how many times people have paired two het amels together. When thinking of it that way, it is inevitable that this will happen to somebody.