Nutritional Needs of Cornish Cross Meat Chickens with Gail Damerow

Cornish-cross meat chickens eat almost constantly and they grow fast, resulting in unique nutritional requirements. Continuing our interview series with Gail Damerow, poultry expert and best-selling author, we ask her to offer tips for meeting the nutritional needs of Cornish Cross meat chickens.
 

What makes Cornish Cross meat chickens different?

Cornish Cross meat chickens are a hybrid cross that grow a broad breast and large thighs. Along with these characteristics, they are efficient feeders, meaning they gain weight faster than usual while eating less feed.

They need only 2 to 3 pounds of feed per pound of final weight. The cockerels reach 7 pounds in just 6 to 8 weeks. Pullets take about a week and a half longer to reach the same size.

This rapid rate of growth can result in a number of health issues, including weak legs and stress on their heart. The older they get, the more likely they are to develop leg deformities and heart failure.

So how can we prevent these problems?

Two ways. One is to harvest them while they’re young. If you let them grow much past the age of 10 weeks, they can go downhill fast.

The other way is to restrict their feed intake to control their voracious appetites. Of course, at the same time, you must meet their nutritional needs.

What are the nutritional needs of Cornish Cross meat chickens?

For their first three weeks of life, these chicks need a starter ration containing at least 20% protein. In some areas, you can get a specific broiler starter formula containing up to 24% protein.

After the first 3 weeks, gradually switch to a broiler grower ration containing 18% to 20% protein. Make the switch by initially mixing the two rations together. Then keep the birds on the grower ration until they’re ready to butcher.

Now, in some areas, all you can find is one all-purpose starter-grower ration. In that case, use the same feed from start to finish. Either way, be sure to always get fresh rations.

What’s so important about fresh rations?

From the time a commercial ration is milled, it starts losing nutritional value through oxidation, eventually becoming rancid. And rancid feed is both toxic and reduces growth rate.

Some feed tags might indicate the ration’s origin date. From there, add time for transportation and storage at the feed store. Turnover at the store depends on how busy the store is.

If turnover is fairly rapid, you can buy enough feed to last up to a month. If you aren’t sure, don’t get more than you will feed out within a couple of weeks.

You said something earlier about restricting feed intake.

Yes. Give your Cornish Cross meat chickens a good start by feeding them free choice for the first week to 10 days. After that, you can control their weight gain by removing the feed overnight. This is called limit feeding.

Do you recommend a medicated starter ration?

Medicated starter contains a coccidiostat to prevent the intestinal disease coccidiosis. This disease interferes with nutrient absorption and thus reduces growth rate.

Coccidiosis is caused by protozoan parasites that thrive in hot, humid weather. However, Cornish meat chickens don’t do well in hot, humid weather. Their rapid metabolism generates internal body heat. Additional ambient heat can cause heat stress leading to heart failure.

So in a climate that experiences hot, humid summers, raise Cornish meat birds either in early spring or in late fall. Since coccidiosis is a lesser problem in cooler seasons, you shouldn’t need a medicated ration.

Any other caveats about raising Cornish Cross meat chickens?

Yes. They are not suitable for altitudes above 5,000 feet. At high altitudes, the air contains less oxygen. To maintain the oxygen level in their blood, the broilers breathe faster and their hearts beat faster. Since they already have a rapid metabolism to start with, the extra stress can lead to heart attacks.

Circling back to nutritional needs, do you recommend any supplements?

A poultry probiotic to stimulate their immune system will help them fend off diseases. Some brands of feed contain a probiotic. Or you can buy a separate probiotic, such as Broiler Booster, as a supplement to use throughout the birds’ lifetime.

What about grit?

Grit is not essential for broilers in confinement that eat only commercial ration, because their saliva softens it enough for digestion. However, offering free choice grit helps them digest the ration more efficiently, so they’ll eat slightly less to get the same nutritional value.

But grit is important for broilers that free range. It lodges in their gizzards, which grinds up their food, acting as teeth to help them digest whatever they forage.

Any final words about nutrition for Cornish Cross?

Yes. Absolutely essential to the nutritional needs of Cornish meat chickens is a continuous supply of fresh water. They need clean, fresh drinking water at all times to aid digestion and help prevent disease.

Raising Cornish meat chickens is a fairly simple short-term project. A successful outcome depends on recognizing the unique nutritional needs of Cornish meat chickens resulting from their extremely rapid rate of growth.