I've seen 6 cases of eary breeding personally from those who sought me out.....4 accidental breedings....dragons out in common space and didn't know it would happen so quick and 2 because someone else told them they were big enough.....one dragon was only 275 grams but the other 5 were over your 300 gram rule. I was involved shortly after breeding in all 6 of these cases....females had good fat stores and were proportionate in weight to length, health and free of parasites. All but one had UVB, all were supplemented and fed properly and provided with appropriate nesting boxes. 2 became egg bound, a 400 grams girl and a 320 gram girl, 2 had clutches with less than a 50% hatch rate and many of the ones hatched died before 8 weeks, 2 clutches had calcium issues after hatching, 1 female had calcium absorption issues after laying(the one without UVB), 3 clutches had between a 70-80 percent hatch rate, one did have a 90 percent hatch rate but those babies were some of the ones with calcium issues. Slow growers and failure to thrives were about 20 percent of the ones who survived. 1 female never grew after laying....was 8 months 15 inches and 330 grams and at 18 months was the same size which is not usual at all.....even at 24 months when I checked back she had not grown.
Even in 18 month or older dragons husbandry can be an issue, so that's a moot point.....
I would welcome the info you your dragons, ages, weights, lengths of your breeders now and when the ages, lengths and weights when they were first bred, hatch rates, mortality rates, slow grower and failure to thrive rates of there offspring. And if any of them have passed, at what age.
As far as my stats....out of 954 eggs, 27 didn't hatch or under 3%, out of the 927 that hatched I lost 11 before 8 weeks, most of those by 4 weeks which is just over 1%......I've had 8 very slow growers (under 6 inches at 8 weeks) which I always keep until they catch up, but the did catch up in size by 14-15 months, 2 in less than 2 months, 1 in 3 months, 3 in 6 months and the others by 14-15 months.
None of my breeders has passed yet....my oldest female is 10.....weighs 600 grams and is 21 inches, was bred at 38 months the first time, had laid one clutch of infertiles the year before.....she bred last at 7 and is still producing one clutch of infertiles per year. I have 2 8 1/2 year old females, bred at 19 and 21 months, 500 and 400 grams each and 20 1/2 and 18 inches long....both bred last at 7 as well....produced one and two clutches of infertile eggs last year. I have 1 7 1/2 year old female, 550 grams and 19 inches, bred at 20 months.....this will be 1st year not bred. I won't go into the ones under that age, as their longevity is no where near established.
Oh for reference...
the oldest female was 17 inches and 400 grams at 6 months, 460 and 18 inches at 11 months and at 18 was 21 and 650(she lost a bit the last year or so)
the 8 1/2 year olds were 300 and 322 at 8 months and 16 and 17 1/2 inches long, and 350 and 400 and 17 inches and 19 1/2 at 15 months ....at 18 months they were 410 and 505 and 18 inches and 20 1/2 inches
the 7 1/2 year old was 374 at 7 months old and 16 1/2 inches long, 420 grams and 17 3/4 inches at 14 months 540 grams and 19 grams at 18 months old.....
so they all had quite a bit of growing to do over that time span
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Tracey 
Tracey's Beardies
www.beardiecrazy.com






