those decimal numbers signify what sexes of each animal you keep. For example, if you have one female cornsnake and no males, then it would read: 0.1.0 cornsnake. Some people also put the color and pattern there and include the year of birth. So you could have 0.1.0 hypo motley cornsnake 2003. The last number (which is not always included) signifies unsexed animals. So if you have frogs or some other kind of animal that is hard to sex, you would list it there. Or if you have a bunch (clutch) of babies that have not been sexed yet, you would list it there. Hope this helps.
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phflame