I got a rat harness for one of my boys who is both blind and deaf. (bred irresponsibly by some 'have a go' breeders) I couldn't train him to come to me when called, so I couldn't easily free range him, and I think he was probably a little bored sitting on my desk/shoulder every day!
He hates the harness, and always manages to wiggle out of it within a few seconds. If it's too tight, the velcro just comes undone (there are a couple of clips as well as backup, but they cannot be adjusted and are way too big to prevent an escape), and if it's too loose then he escapes by squeezing through the harness like a tunnel. It's a very comfortable feeling harness but he just wasn't used to it at a young age, so I suppose that was it. If you're going to use a harness on your rats, I'd advise you to try and get them used to it when they're very small.

He's probably do well if he was free ranged in a play pen. You can make these fairly cheaply out of correx, and it would mean he was able to explore more then he could if he was on a lead, and he couldn't escape to anywhere where he could harm himself.

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Cara,
Owned by Fern, Heidi, Asteroid, Bubbles & Fizz
Missing Snippet, Frost, Willow & Nix


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