The tractor seems to be working perfectly now. I shift it every two days: by then the meat hybrids have thoroughly soiled the ground. They seem to be enjoying the sun and the grass — it's such a lovely sight when they take a break from eating to sunbathe.
They're now 7 weeks old (plus a day or two) and while there's a fair bit of variation in size, none is looking seedy. I did roll the tractor edge over a cockerel accidentally this morning — I couldn't see past the tarp as I was very slowly dragging — but he doesn't appear to have been harmed. Thank heavens! This didn't start with a desire to save money but to raise healthy chickens as humanely as possible.
Their feed is still 50% commercial grower and 50% home mix (sprouted wheat, corn and peas; cracked sweet lupins; sunflower and lucerne with molasses water, seaweed meal and the one I always forget to mention, salt). On top of that I add an afternoon treat which is high in methionine — 50% soured or skim milk with rolled oats to soak the moisture up, and 50% pet mince which has been rinsed thoroughly in hot water to remove sulphur dioxide preservative. They wolf it down, but then they wolf everything down. :)
You can see what the daily feed looks like behind the dozing birds in the photo below:
They really eat a lot, and drink a lot:
Their growth rate is just about what I want. By that I mean, they aren't gaining weight so fast that they won't be able to walk in another week or two. A couple are quite big but the majority are nicely balanced and even hop up into the upright feeder sometimes. I like to see birds that can perch if they want to (even if for safety's sake there's no perch there).
The photo below shows one of the heaviest cockerels... I think 10 weeks might just about be a maximum he'll get to before leg issues occur. But I'll be happy if all the cockerels make 12 weeks and in a few cases 14. As for the pullets, as soon as I've made the meat selections, I'll start increasing the time between morning and afternoon feeds so they do a bit more foraging. At the moment feed is available all day, and I'm relying on its higher fibre content (compared to fully commercial feed), slower progress through the digestive system, and more 'satisfying' nature to keep the birds' weight from skyrocketing.
They're sleeping on the ground under the tarp, as the cold brooder was taken out some time ago. No more mats, either — they don't need them unless it's raining so heavily that water is trickling underneath the tarp. Temperatures at night are getting down around 5C, with a frost about 3 days ago (so it must have been near zero celcius). I'm happy with how they look, and in fact when I went out to check on them on the coldest night the area under the tarp was surprisingly warm. They have such high metabolisms they really crank out the heat.
But just on the subject of looks, as you can see, the feathering is still patchy on some. Here's the worst one:
It looks bizarre and the fact that I had a similar issue with the sussex was what made me review the diet for methionine. Having said that, the layer chicks raised partly with the meat birds above feathered properly.
Still, as things go I'm quite happy with the balance between growth and chicken health. In future I'll only brood 15 (not 30) to reduce coccidiosis issues, and I'll pay more attention to weather reports as well as seeding the brooder gradually with adult droppings. The fact that these birds had to be shifted to new brooders three times (because they outgrew each one) meant that each new brooder run was also probably devoid of coccidia to start with. Thus when they hit the ground under the tractor they were hit with a massive increase in oocysts (especially when it rained). Well, that's my thinking, faulty as it may prove to be...
Then again, if I get breeders from this batch and manage to hatch offspring that are a little lighter and healthier, then I probably won't get meat hybrids again. That's the plan! :)