My rather eccentric MIL has just handed me a huge pile of egg shells she has been collecting and baking for months (by the size of the pile, since her last hens went a year or 2 ago as she was saving them in case she got more). She told me to feed them to the hens - so couple of questions -
how much should I give them -
should it be mixed with other grit or is egg shells alone enough
is there an expiry on baked egg shells after which I should use them for slug repellant instead?