I also semi free range during daylight hours. I have a very large fenced area that they can range in. I have 40 birds and it still has grass over 80% of it, so it's definitely large enough. And I have Fayoumi's who are digging demons, so a lot is dug up. Mine have to be fenced due to roaming dogs (not mine) and an aircraft runway that they have to be kept off of. It does help with feed, especially in the summer. The only 'nutritional' related issues I have is when a bird has an underlying health issue (old age, cancers, etc) or the occasional bird in molt who feels lousy and doesn't eat well.
