Study: Whole grains improve broiler feed efficiency

Research from Australia reveals that replacing some ground grain with whole grain leads to better poultry yields

New research from Australia suggests that replacing some of the ground wheat in broiler diets with whole grains could not only make meat production more efficient, but also contribute to improve food security in developing countries.

Studies at the Poultry Research Foundation at the University of Sydney reveal that the addition of the whole wheat to the diet leads to the muscular development of the bird’s gizzard, reports Poultry Hub, the website of Poultry CRC. The gizzard not only grinds up the feed more efficiently, it also appears to stimulate the gastric juices.

“I found that by replacing 30 percent of ground grain with whole grain, the chickens produced 7.7 percent more meat per kilo of feed eaten,” said Amy Moss, lead researcher on the project.

Whole grain feeding does not make broiler diets more expensive. According to Moss, it actually reduces the costs of milling and making the feed.

She has calculated that if this change were made in developing countries in Africa, Asia and the Americas where whole grain feeding is not normal commercial practice, 100 million people could benefit from cheaper chicken meat.

Moss is currently a PhD candidate at the Poultry Research Foundation at the University of Sydney. Her research has been partially funded by the AgriFutures Australia Chicken Meat program.

Presenting the study at the 2018 Australian Poultry Science Symposium earlier this year, Moss reported that one of seven dietary treatments was fed to broiler chicks from seven to 28 days of age. The six test diets included whole wheat at levels of 7.5, 15 or 30 percent, added either pre- or post-pelleting. For the post-pelleting treatments, the whole grain and a pelleted concentrate were offered to the birds in separate feed trays, so the broilers could choice-feed. A standard ground grain diet was used as a control.

At 1.260, the most efficient treatment in terms of feed conversion was achieved by the birds fed the 30 percent whole wheat diet where the birds could self-select their diet between the grain and the concentrate. Broilers fed diet containing 30 percent whole wheat added pre-pelleting had a feed conversion rate of 1.365—seven per cent less efficient than their choice-fed counterparts.

It would be expected that the birds on the post-feeding dietary treatments would select the whole wheat and concentrate element so that they consumed similar amounts of protein daily. However, the researchers noted that the birds fed the separate 30 per cent whole wheat diet showed a greater preference for the high-protein concentrate, and ate significantly more of it, than those fed lower proportions of whole grain.

This opportunity of choice feeding and preference for the concentrate would have contributed to the enhanced performance of the whole-grain feeding regimes, commented Moss and her co-authors.

Previous published data on the effects of whole grain feeding on the performance of broilers reveals inconsistent effects, according to a 2014 study. Interest in the practice from the poultry industry tends to grow when grain prices are high, and consumers tend to favor it as a “more natural” way of feeding animals.