Hello 
@Cryss  I am sorry I do not have your answers, but your post has got me thinking.  I grew up in NJ and as a teenager got lyme (and knew many people and animals that were adversely affected in many different and profound ways), had the bullseye and months of antibiotics that made me ill in other ways.  I can't help but wonder years later if my "arthritis" like symptoms on some days actually stem from lyme.  Fortunately we do  not really have ticks where I live now, but after reading your post and the replies of others I will certainly give some guineas a good home if I relocate somewhere with ticks.  I like your idea of free ranging meat birds.  What about turkeys?  Do they eat ticks?  I feel that they would do well free-ranging and due to size maybe one could eat a lot of insects?  I don't know for sure.  Hopefully others will weigh in.  Or what if you adopt some retired layers or battery hens that could free range.  They would have a good home for the rest of their lives and otherwise would have been culled from their flocks.  Even if they are lost to predators you would have given them another chance at a good life and they would be able to help you out.  If you make this decision prior to getting the birds it will be easier to accept their possible fate than to turn loose birds you have hand raised for years.  It is similar with my "free to good home" oops cat that I adopted to take care of rodents.  I know that one day he probably won't come home, but he will work for me, and I will love him and care for him, and he will have a great life being able to hunt and play outdoors.  My indoor cat is quite envious at times and begs to go out if he is out hunting.  Know that if you free range birds, that while their life may be shortened, their quality of life is greater.