Growers Guide to Mistral Gris

Raising Mistral Gris is not precision science – they are robust birds and will make the best of any brooding and grow-out conditions they are given.

Mistral Gris look a lot like Barred Rocks, with black and white barred feathers, single combs and yellow skin. They were bred from Barred Rocks and several other heritage breeds using old-fashioned breeding techniques and a ‘3 way cross’. It takes at least 10 generations to perfect a cross like this, and the parent/grandparent lines need to be refreshed every 4 years, so they are an ongoing project here at the farm. No genetic engineering or ‘terminal genes’ have been used, but the Gris grow too large to be good breeders themselves.

Environmental Factors for feed and growth

The biggest environmental factor that affects feeding requirements is temperature –

If the birds are cold they will ‘spend’ more carbs on keeping warm. Because of their lovely feathers, Mistral Gris can be quite comfortable in cold weather, but they need to eat more food. Providing a cozy, dry area for them to retreat to will save you money on your feed bill.

Being too hot has it’s problems as well. In hot weather they will drink more water and process their food faster and less efficiently. They should always have access to shade, and not have to crowd together to get into that shade.

Chickens like dry, not wet. If they are indoors, make sure their litter is dry. Wet litter will generate ammonia, which is hard on their eyes and lungs, and will reduce their growth rate. Outdoor Mistral Gris are fine running around in the rain or through wet grass, but they should always have a dry place to rest and warm up in.

Some feed tips:

-For the first 6 weeks offer free feeding, with food always accessible. Most people take the food away at night after that. Some give the birds access to feed several times a day.

-When you feed, make sure that all of the birds in a group can feed at the same time. That might mean providing long line feeders.

-If you are raising more than 25 chicks, or putting them into tractors, we recommend to separate the boys from the girls after about 6 weeks, The girls will do much better without the competition.

-Keep the final goal in mind: Boys 4 kg at 12 weeks, Girls 3.6 kg at 12 weeks. (Chart below)

-You can feed more and increase their protein by giving access to feed longer, by increasing the richness of the feed, or by supplementing with a rich feed – anything with animal protein in it works very well! Dairy products of all kinds, cooked egg, bugs, worms, meat scrap...

-You can feed less by reducing access to feed or by feeding a leaner feed. You may wonder why anyone would want to reduce the growth rate of a meat bird. The main reason is that you want to eat meat, not fat – a bird that is growing ‘too fast’ is putting on a lot of fat. This can be a good reason to put them on a lower percentage “finisher” grain in the last two weeks of growth. 

What to feed

-You can start your chicks on newly bought, high protein Starter feed (around 22%), but wean them over to 17-20% Grower feed between 3 and 6 weeks old. I find that one bag of Starter is just about right for 25 Mistral Gris for their first 3 weeks. It is important to move the birds to a grower as this will have the energy and calories they need to grow well.  

-in our experience we have found the best success having good size, very tasty meat at 12 weeks, by using a 19% organic grower from 2 weeks old. We also love to finish our birds with non-gmo corn and dairy to create an exceptional meat flavour! We highly recommend Pete's organic feed - 19% HD grower which is formulated specifically for active meat birds.

-Some people choose to use medicated starter for the first 2 weeks. This can help if your chickens are in less than sterile conditions. It contains amperol and temporarily inhibits the growth of Cocci parasites.

-Most pastures do not have a lot of digestible forage for chickens. They will eat grass, but they cannot digest cellulose, so it’s not much food. What a foraging chicken is looking for is bugs, worms, mice, carrion, manure from other animals, and soft leaved high-protein plants. If you can plant your chicken runs with legumes, amaranth, dandelions, etc. there will be more food value in it for your chickens. In the meantime, do not assume that you should cut back on their feed because they are on grass - they aren’t herbivores. 

-Organic feed can be wonderful for raising meat birds. Some has more of a mash consistency. It can be helpful to add a bit of water to thicken up the powdery bits of the feed. The chickens love this mash!

About Processing:

The Mistral Gris reach 5 lbs (live weight) by 9/10weeks old, dressing out to meaty fryers, but in our opinion, they are at their best raised till about 12/13 weeks, when they become the best roasters you'll ever eat. They average about 3.5-6.5lbs at this time. You can even raise them longer for more size and many people report enjoying raising them to 16 weeks for some small turkey sized chickens!

If your birds are on a lower protein, or growing a bit slower, you can raise them longer as an option. After about 10 weeks they can put on quite a bit of weight each week, so raising them until 13-14 weeks (if you find your birds are smaller than the growth chart suggests) can really make a big impact to their finished weight and make the whole process more worthwhile.

Remember that Mistral Gris are not ‘broilers’ and should not be ‘signed in’ at the processors as such. ‘Broiler’ is a key word for the Marketing Boards and the CFIA that can trigger enforcement of non-quota limits and the like. Say the MGs are ‘heritage meat birds’, and you can identify Tevah Acres Hatchery as your source of chicks.

Mistral Gris benefit from a 2 day ‘rest’ period after processing before freezing. This will help them to be even more tender when cooked. It isn't necessary if you don't have the fridge space, but we do find it helpful. 

When finished, they have broader breasts and heavier thighs than other competitive meat breeds. Despite the black feathers, they dress very cleanly. Rub with butter and roast on a slightly lower temperature, for a bit longer, for the most divine chicken dinner ever!