Turkeys should start out on wild game bird stater, starter grower, or turkey starter usually 22% to 24% protein. This has the needed vitamins, grit, proteins, and minerals.
We always use medicated feed to start with at least until after 7 to 9 weeks
At abut 4 weeks you can start to add grass. We add extra small grit at this time.
At 10 weeks you can easily switch to a grower wild game ration, or regular turkey feed, with grit, grass and corn supplements.
You can change the percentage of protein in your feed by adding a 18% generic poultery feed.
If you add oyster shells for calcium you must put a vitemins supplement in there water. This is because a turkey need a mineral to motabilise the extra calcium. If you don't then you will have a lot of whats called crocked leg problems. which is about 6 different malidities rolled into one word.
Cornish X type birds should stay on a starter ration until at least 5 to 6 weeks then on a grower ration until the last week or so then a finisher ration for chickens the last week. Or you can use a starter/grower combination until the last week.By week 8 or 9 when you process they should be large and alive. If they are growing to fast, then you might need to remove there feed at night.
Broilers need to stay on a 20 to 22% starter ration until at least 6 to 7 weeks, then you can switch to a grower ration. Which it about 18% protein. we start adding grasses at about 7 weeks. and about three times a weeks they get scratch or sweet feed.
Our layers stay on starter until about 10 weeks then we switch to a grower ration, with grass, grit, and some scratch or sweet feed. They start with oyster shell at about 19 weeks. and go on layer rations at around 20 to 22 weeks.
So far we have only lost one adult Barbed Rock who was over weight and we did not get her as a chick, and one chick in two years.
As for the turkeys we messed up this year and added the oyster shell to soon with out the viteman suppliment and had 3 with crocked leg out of 16 turkey pullets by week 4. We had lost two of them so far. As far as the 50 plus or so chicks we have only lost one when it feel into the waterer the first day.
If you have your Hens raising your chicks then the feeding schedule is some what different.
Since the chicks will eat the adults poo and the vitemans, mineral, and antibodies they get from that will be different. This isn't so much a topic for chickens, but turkeys it is.
Of course the type of grass they get can make a difference, regualar lawn type grass won't do as well as some hardier types. Generally use wide bladed grass for your poultery.
Although you can usually buy grit we have some gravel that's called concrete mix, (it doesn't actually have concrete in it just sand and gravel). We sift it through a wire mesh that's about 1/8 square or so. This leaves the sand and larger gravel as the chicks (turkey and broilers) get older they start to leave more of the sand size grit the grit trays.
Tom