Is it safe to give crushed adult grit for a 5-weeks old chick?

[thunder21]

Hello! I have 5 weeks old chick and I've been giving him treats since he was 2 weeks old. I wasn't able to give him chick grit because it's not available in my country. And today, my chick found a mice and he swallowed it whole. And I'm worried how can his gizzard digest it if he doesn't consume any grit. He's not a free-range chick. So, is it okay to give him crush adult grit? If not, is there any alternative or DIY chick grit? Thanks a lot!

 

[rosemarythyme]

Probably don't even need to crush it if you have different sizes of stones in your grit. As far as what to look for in sizes: