i have 10 hens [free range] and they all seem to have stopped laying within a few days of each other.they are all eating well [garvo pellets]with a little corn & veg scraps in the afternoon,all are lively &" talkative" & have good red combs.no sign of mite,the hens seem totally content although i never have had as many eggs as i expected,about 6 a day.i know they slow down now but surely it's not natural to stop completly.hens are all between 8mnths.& 1year old.any advice?