chickens

by billy
(hampshire, england)

i have 19 chickens but about 3 days ago i had 21. one is ill and a bantam is looking a bit poorly as well. for the first bird, it stopped eating and soon after lost its balance and then died. the second to die had a severly blocked crop, i tried everything to unblock it but it just wouldn't so it passed away. but my 19th hen ,a light sussex, has stopped eating and has started to lose its balance like the 21st hen BUT my 21st hen was around two and a half years old and the light sussex i bought at POL only the other week.also the bantam looks a bit weak on its legs as well and sometimes lose its balance. Is there really something wrong or is it just a co-incidence. could it be something viral and is going around the flock? also i did have an early case of red mite earlier in the year but i dusted all birds in red mite powder and got a new coop.

thanks for helping, billy