bc,
heres the link, if I did it wrong just copy and paste, everything you need to know is on the web site..
http://spalding-labs.com/If your birds are in pens I bet you could get away with the smallest order since they are not free ranging.
Good luck, Norma
P.S. Just got my May order in and am waiting for them to hatch so I can spread them around the place. I also use the smallest order and they have done VERY well for me...njb