Hellos,
The general consensus on MBD is that it is curable if caught early enough, but the disfiguring damage in permanent. In other words, if it goes for so long that the spine gets twisted and the bones get deformed, you can always put calcium back in the bones by they will never straighten themselves back out again.
My Xander was diagnosed with mild/early MBD almost a year ago. The only signs we had were stunted growth and a broken leg. When we took him in for the leg, the vet noticed the poor bone density on the x-ray, and mentioned MBD to us.
We re-researched everything iguana... read every book we could get our hands on and bought three... changed his lights, diet, humidity, and added calcium and regular sunlight exposure. Three months later, he went back to the vet for another X-ray and his bone density was 100% better. Today, he has completely recovered, but he is smaller than the average 2-year-old and may never grow to reach his full 6' potential just because he was stunted so early on in life.
I've read that females who have had a history of MBD may have problems with egg binding in the future, even if they have fully recovered.
Hope that answers your question.
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~Alika~
1.0.0 green iguanas
0.1.0 cockatiels
1.0.0 senegal parrots
0.1.0 blue-fronted amazons
0.0.1 red belly piranha