Scappi, I have found has a wealth of knowledge on subjects I never imagined I would find in a cook book, let alone a cook book from the 16th century. I am investigating right now and re reading recipes in order to create the feat for Accedemia Della Danza this coming March and was in Book VI, dishes for the sick when I noticed that he makes reference to the fact that the poultry should not be cooped or force fed.
The recipe on page 551 number 32, To prepare a paste of chickens cooked in pastry. He states "Get the breast of a meaty chicken, not one that has been force-fed, but killed that day." There is a foot note and the foot note states " Ken Alba points out that physicians held the flesh of captive animals and of cooped, force-fed fowl to be less nourishing and less readily digested than that of their free-ranging counterparts." The foot not further states that his reference is to Thomas Moffett's "Health Improvement" written in 1595 and uses the quote: "Whether (the) penning up of birds, and want of excersise, and depriving them of light, and cramming them so often with strange meat, makes not their flesh as unwholsom to us as wel as fatr. "
The modern practice of factory farming is in fact not modern. I can not imagine what would possess someone to want to coop up their fowl and keep them in bad condition. Besides being animal cruelty, fowl kept this way we know are more susceptable to diseases, loss of eggs and other problems.