Just a status update.
Two days ago I began to fear that even the new larger brooder wouldn't cope with 30 meat hybrids and their rate of growth, so I made up an el cheapo cold brooding hutch and set it up inside the chicken tractor.
Wouldn't you know it, an hour later it began to absolutely pour! Only half the tractor is covered, and it's very open to weather — not a great situation for 3 week old birds (not to mention the 3 layer chicks that are probably only 2 weeks old).
But I needn't have worried. After having to put them in the new igloo on that first night, I found that they used it automatically from then on. They are getting a bit wet in the open, but not wet enough to chill, and they huddle in the cold brooder happily if they feel cold in the day. As usual they emerge at full tilt and eat themselves stupid.
What a relief! I must say I wouldn't have moved them until after the wet weather if I'd known it was coming.
Now for the diet update — over this week I've been reducing the medicated starter in favour of the home mix. It's now at 50% commercial. I don't want to do it too fast this time as I'm concerned about their gizzards being able to handle harder grains. I'm still adding very small amounts of meat and soy meal, but the basic protein content is coming from legumes. Later in the day they're getting a small amount of human grade mince mixed with oatmeal and kefir or similar, to supplement with animal proteins.
Cracked corn and millet are the (unsprouted of course) grain element, then I'm adding other ingredients like lucerne, sunflower, livamol, yeast, lupins, etc as per the usual diet. The protein content is around 20%. Recommended meat hybrid diets are more like 22 or 23%, but I suspect this is purely for high production and growth rates — and I don't actually want that. I want the birds to live a little longer in peace, without going off their legs or developing cardiac failure. A tall order given the breed, but let's see... (It's worth adding the note that artificial methionine is associated with cardiomyopathy.)
Next item on the agenda is a grain cracker — the chicks aren't keen on the whole sunflowers, and I can't find a supplier for fresh sunflower meal unless it's doctored with various vitamin premixes (such as the horse supplement I came across). I might invest in a grain cracker to make the most of things like whole sunflower seeds (which chicks aren't keen to try yet).
Over the next few days I'll be cutting out commercial starter altogether. I'm seeing no cocci signs but of course the birds are a bit too young to show the most common signs. The ground has been very wet so almost certainly they're under challenge, especially given the higher than usual number of birds.
Sitting among them trying to get them used to the new igloo was really strange... They're not at all identical in personality, and there was one meat hybrid boy who wanted to come and sit under my hand.
I wish I could free range them completely — but not here, not with the goshawks. Then again they seem as happy as chickens can be, scratching in the dirt and running about. Let's hope it lasts for several weeks longer yet.