Reptile & Amphibian Forums

it never gets old finding these. This is always a good sign of what's to come she laid 5 eggs last year and 7 this year even though we had to fight for rats in 2003 (rat shortage) she got what she needed to produce 2 more eggs. She went from 2400 grams Saturday to 1500 grams after laying today. It's amazing how much these animals put out for reproduction.

Debra and Diana
Camlon Reptiles

And she STILL looks like a fatty! Great stuff!

it is unbelievable what they can do.....losing a third to half their body weight and bouncing back the following year.
Congrats Debra and Diana. What's cooking in the eggs?

Good luck with the rest of your egg laying and hatching season.
Joe
Joe Compel Reptiles

We're really excited about this girl becasue she produced the Mojave's that have very washed out sides that we held back, and can't wait to see if she does it again.

Debra and Diana
Camlon Reptiles

show us some pics when they hatch.
Good luck - I hope you hatch a bunch of mojaves.

Joe

Joe Compel Reptiles

I've not seen much over 1/3 pre-lay weight loss in the data I've seen and it's been pretty consistent right around 1/3. The nice even numbers given above show 37.5% loss and while that's not far off 1/3 I'm wondering if their might be some rounding involved and she is even closer to 33.3%. Just imagine if she had laid 80 gram eggs rather than nearly 130 gram ones, then there would have been 11!

Congrats by the way.

many females do seem to lose about a third of their body weight.
This year I have kept accurate weights of females just before and after egg laying. I have also been keeping track of clutch masses too. I have good data for almost all of my 16 clutches to date. You are correct when you say many females seem to lose about a third of their body mass. When all is said and done this season, I hope to put a page up on my site with some weight loss data.
Prior to this season, I would check wieghts of females that looked real skinny after laying (or before laying). A couple of years ago I had a female that showed a dramatic weight loss. She was a young breeder (bred in her second winter) and was just shy of 1600 grams. She laid 6 big fertile eggs. At the time, the only reason I weighed her was because I was surprised at how thin she looked and how big her eggs were for her size. I'd have to check her cards to be exact, but I remeber she lost close to half her body mass. Her post egg laying weight was in the low 800 gram range.

Joe Compel Reptiles

Joe,

I look forward to seeing your page as I really haven't looked at all that many egg loss weights yet.

Perhaps you could also note the number of eggs or the average egg weight. From the few clutches I've looked at it seems that egg size varies a lot more than the percent of pre-lay weight into the clutch. We probably wouldn't want to breed for more than 1/3 weight loss anyway as that is just increasable already.

However, I was wondering if it would be possible to breed for a large female that lays lots of small eggs. I get a feel that bigger females tend to lay bigger individual eggs but don't know how proven and pronounced this might be (i.e. do most all females lay bigger eggs as they grow?) and also how much this trend (if real) might account for different egg sizes and how much might be genetic differences between individuals. Perhaps an efficiency rating of female weight (maybe post lay since that is when you will be counting and weighing the eggs anyway) divided by average egg weight could be made as an aid in locating females that tend to lay relatively small eggs for their size. If you could breed the most efficient females into the biggest lines (hopefully the two aren't mutually exclusive) then you might be able to produce a super ball that easily lays 20 eggs when mature (a 4,800 gram female laying 1/3 of her weight in 80 gram eggs would produce 20 eggs).

Some may have a strong feeling that smaller eggs and hence smaller baby balls are not a good idea so I would also be interested in comments from those who hatch smaller babies on how they do. In 2000 I hatched twins in the low to mid 30 gram range and they didn't miss a beat but maybe I was just lucky. I'm thinking that balls have a small number of relatively large babies in order to fill a niche in the wild (i.e. like being able to exploit a single prey species all of their life rather than having to rely on one species for babies and another for adults) and that in captivity we really don't need baby balls to be as big as they are. Seems that they grow so fast anyway that the difference between a 50 and a 100 gram hatchling is only a few weeks.

So, anyone want to start calculating a "BPMER" (Ball Python Maternal Efficiency Rating)? If we agree upon post lay weight divided by average egg weight it would be something like this.

A 4,800 gram female that lays 20 eggs averaging 80 grams leaving a post lay weight of 3,200 grams would have a BPMER = 3,200/80 = 40

A prelay 1,980 gram female that lays 6 eggs at 110 grams each (post lay weight of 1,320) would have a BPMER of 1,320/110 = 12

The usefulness would be if you could identify the animals with the genetics to have a BPMER close to 40 when they are not fully grown and breed them into the big lines and see if they can keep the high BPMER. If I knew the egg size stayed the same as they got bigger all we would have to do is select for small egg size but maybe an 80 gram egg is too small to expect from the really big ones and we need some way like the BPMER to adjust for the size of the female.

What was she bred too?
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Jason
JH Reptiles
www.jhreptiles.homestead.com

Sorry to hear about the rat shortage out there, We bypassed that problem by producing our own rats.. Ever think about trying to raise them? we started about a year ago and now we have about 300 breeder females and basically have a unlimited supply With automatic watering systems and feed on the top of the breeder racks, its a pretty easy daily task to maintain. Plus we KNOW what our rats are eating (Mazzuri Rodent Breeder 6F) And our snakes LOVE EM.

Bryan

our own rats, but the colonies we had established weren't enough to fit the demand that we needed. We had to buy more Freedom Breeder racks to solve this issue, and up the amount of breeder colonies that we have. We feed Teklad Lab Diet because Teklad is located in our city. Hopefully we have solved the problem now, and all our females will be big and lay 14 eggs instead of 7! We wish.

Thank you,

Debra and Diana
Camlon Reptiles