This is a sign of renal failure... the kidneys also regulate calcium metabolism. If the kidneys fail... needed calcium is taken from the bone. Leopards seem to be extremely suseptable to entameoba infection in general but babies are more so. It's very difficult to bring them back once the shell goes soft. This is one reason why I push a pelleted diet like Mazuri so hard... it provides a balanced diet and is low or lacking in oxalic acid which I believe is a major cause of renal failure.
It sounds like they are already septic. Is the coloration red?
>>I sold some leopard babies to a lady about six months ago. She brought two of them back with soft shells. One is soft on the bottom and the other is soft all the way around. Both are dark/discolored on the bottom. Both are still picking at food but becoming less active. They have been showing these symptoms for a couple of months and were housed together with others that are not showing any symptoms. If anybody has had this or has an idea of what caused it, I could use some help.
>>Thanks in advance.
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Ed @ Tortoise Keepers
Trying to keep the fun in Chelonian care