This information is provided by Provet for educational purposes only.
You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.
AN INABILITY TO INCREASE CALCIUM ABSORPTION MAY EXPLAIN THE APPARENT HIGH INCIDENCE OF NUTRITIONAL SECONDARY HYPERPARATHYROIDISM IN REPTILES AND CHELONIA
Nutritional secondary hyperparathyroidism is common in captive reptiles and chelonia, and mineral supplementation is frequently advised.
In a recent study conducted in captive Galapagos Giant Tortoises (1) the digestibility of calcium was less when they were fed a ration containing a lower concentration of calcium (0.97%) than when they were fed a ration containing a higher calcium concentration (5.72%). This was an unusual finding because in most species the % calcium absorbed increases as the concentration of calcium decreases.
More studies are needed, but if chelonia (and possibly reptiles) are unable to increase calcium absorption in response to low dietary calcium concentrations, this may explain why nutritional secondary hyperparathyroidism is seen so frequently. It also means that further studies are needed to determine the optimum mineral concentrations in rations intended for these exotic species.
Chelonia should never be fed an exclusively meat-based diet as this is devoid of calcium and will induce nutritional secondary hyperparathyroidism.
1. (Liesegang A et al "Comparisons of digestibilities of calcium, phosphorus and magnesium between different diets in captive born juvenile Galapagos Giant Tortoises" Proceedings of the 3rd ESVCN Congress 1999)