Hatching platynota - an ongoing research project.

Markw84

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Our 6th clutch of the year pipped 2 days ago, and today about 1/2 of them were out of the egg and ready for the brooder box. We are nearing 250 platynota babies hatched. This clutch will make 246, and we have 5 more clutches in the incubator.

A cool bakers dozen hatching- 100% hatching:

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As soon as they are out of egg on their own Brenda rinses them off and lets them soak for the first time:

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We let them soak a minimum of 30 minutes. They immediately drink and then will become quite active. I also then weight them all and take a picture for identification as I track all hatchlings.

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We take that time to prepare their brooder box. I cut up some greenleaf, plantain (large and narrow) grape leaves, hibiscus leaves and flowers and some of their egg shells. I cut all of those up with herb scissors so the pieces are thin strips. We then place some honeysuckle branches and larger plantain leaves for cover. This brooder box goes back in an incubator with lighting for photoperiod. They stay in the brooder box until they pass their first solid feces. Normally 7-8 days for platynota. They are soaked every day and the box cleaned and new food put in.

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For those interested in data:
This clutch took 127 days to hatch. That is 5 days longer than my normal and easily accounted for as I left them in diapause an extra 5 days. Just wanted to see what a little longer diapause would do to the overall time required. I normally diapause in a modified wine cooler set to 69° in the nighttime. The cooling is on a timer and goes off for 14 hours where I let the eggs "warm" to room temperature (normally 75°-77° but can be cooler on cooler days) So they gradually warm each day to their high temp, then at 10 PM cool back down to 69° I feel this is the closest I can come to what I believe a nest in their natural range would be doing the time of year they lay eggs. I leave them in this cooler for 30 days. Then put them in an incubator set at 83° for 12 hours then goes off to allow a bit of a cool-down. I leave them there for 7 days then incubate. I did set these eggs to try to get a bit more males as I have been getting a high percentage of females, so wanted to dial it down to see where I found a pivot point to start getting more males. I do use fluctuating temperatures with a 2° temp drop. So I set these to go to a 85°-87° temp range about 15 days after I started full incubation. I did that for about 30 days ( middle of incubation) then ramped up 1° for 15 days then another 1° for the remainder of incubation. Here is the actual graph I keep of the entire incubation process.


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On the top of the graph I created formulas to automatically calculate degree hours weekly for comparison later once I know sex data on a clutch. I have records like this for all my clutches and have also been doing this will all our Galapagos clutches. Good data that can be referred back to once sex is determined. The rows look at total degree hours per week, degree hours over pivot point per week, and average temperature per week.

I also track weight retention for incubation duration as We have for the Galapagos. For platynota, the average egg weight varies by female from 29.3g to 37.7g. Not at all corresponding to the size of the female. My hatchlings average 122 total incubation days including diapause. 81 days from end of diapause. When they hatch, they average 78.5% of the weight of the egg when it was laid. This is higher than we average for Galapagos.
 

Markw84

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Wow thats'really great!
How do you know you are getting a lot of females?
I've held back some until I could sex them. I also try to encourage those who get babies from me to stay in touch as I wanted to keep track of sex for my research. Lots of those folks call me with questions too. Some want to add more to their group. From all those I do know of, my initial temperatures have given about 80% female overall.
 

PA2019

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What would be VERY interesting is if you could track a similar process for Pyxis. No TSD has been proven for them, and with so few eggs, no breeders have been very adventurous with incubation methods thus far. This has led to very high male to female ratios in private hands.
 

Tom

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So at 85-87 during the actual incubation you are getting 80% female? That's interesting. Not like other species at all. This would explain why so many that are "incubated for female" by other breeders are male. I incubate platynota at a steady 88, after 4-6 weeks of sitting at room temp in my living room, and the ones that I've been able to keep track of have all been male. I would expect 85-87 with sulcatas to produce at least half males, if not more than half.
 

PA2019

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So at 85-87 during the actual incubation you are getting 80% female? That's interesting. Not like other species at all. This would explain why so many that are "incubated for female" by other breeders are male. I incubate platynota at a steady 88, after 4-6 weeks of sitting at room temp in my living room, and the ones that I've been able to keep track of have all been male. I would expect 85-87 with sulcatas to produce at least half males, if not more than half.

Agreed, this might be huge for other species which require diapause! I like what I am reading, go Mark go!
 

turtlesteve

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Chaco tortoises diapause as well and I am quite certain they undergo “normal” TSD patterns consistent with other species - warmer temps reliably produce females and cooler gives males. I do not have data for Pyxis yet but I have observed a higher rate of split scutes in female arachnoides (which normally agrees with high temp = female).

I will admit I’m a bit skeptical that platynota have a wildly different TSD pattern but it’s been confirmed in other reptiles, so who knows, and the theoretical “complete” pattern is supposed to be males at high and low temps and females at moderate temps. I am sure it’s environmentally controlled, otherwise we would not hear stories of people getting all of one sex so frequently.

Keep doing what you’re doing and teach us all something!!!
 

Markw84

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So at 85-87 during the actual incubation you are getting 80% female? That's interesting. Not like other species at all. This would explain why so many that are "incubated for female" by other breeders are male. I incubate platynota at a steady 88, after 4-6 weeks of sitting at room temp in my living room, and the ones that I've been able to keep track of have all been male. I would expect 85-87 with sulcatas to produce at least half males, if not more than half.
Tom. I adjusted this clutch to lower temps. Previously I was incubating at 89°/86° as my daily cycle. Often creeping to 90°/87. I did the 3° temp drop to hedge against split scutes at the higher temps. I only had 1 baby with abnormal scutes out of 245 so far. That one had a very small extra vertebral by the 4th.

So the 87°/85° you see here is an effort to produce more males. I believe the pivot point for Platynota is 86.5°. But I’m also becoming inclined towards believing diapause temps and duration also will scre that result perhaps cumulative degree hours under a certain temperature makes it harder for the higher temps later to overcome.
 
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