Farm Animal studies- studies of Cows and chickens -part I

As part of my new projects for 2010-2011, I am studying farm animals such as Cows, chickens, etc. Another goal that I have for this year is to start drawing a lot more as I would love to be able to do some large charcoal drawings at some point.  So to combine both goals, I have started to go every 2 days outdoor to sketch form life.
I am primarily a sculptor so I usually model directly form life and I don't really tends to draw to do a sculpture. I can produce volumes,modeling from life (i.e. a 3D representation) but  to produce a 2D representation from life modeling is rather intimidating at first! especially when you draw form animals...as they move constantly! this is rather strange as it doesn't bother me when I sculpt form life...
anyway just to come back to the subject, I will be producing a large amount of life studies of farm animals, horses and wildlife over the next year or so. All of the studies will be done from life but i still need to understand how I am suppose to use my daily sketch book/studies and using them to produce larger drawings???

here is the first few studies ( selection of few as there are lost of them!)
Cows  - here are the ladies...and boys.

Quick gesture movement studies - pencils used: pierre noire ( very similar to charcoal pencil)

Quick studies- quick lines

here are the chickens - those drawings have been prepared a lot more- using charcoal.