The average quarantine practice here is 6 -12 months. I do 6 months minimum for each one of my snakes. Im not saying everyone does it, but some harmful agents can live dormant for ~9 months before breaking out. When a zoo quarantines their new animals, you can bet its 6 months or longer. Same thing goes for if one moves to a certain country or vice versa. Its to protect the resident animals. The point being animals can pass other things to each other. And I'm not talking about RI or mites, which are pretty obvious to identify in a few weeks or less, like you said. Some people have invested thousands of dollars in some collections. It would be very sad and a huge waste if an outbreak of something occurred in a large collection due to poor quarantine procedures. Like I mentioned before, better safe than sorry.
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