High-shear dry extruded corn and soybeans and the quest for higher growth performance in modern broiler genetics.
Feeding young broilers during the first 10 days post-hatch is the new frontier in poultry nutrition. The same holds true for any effort to boost life-time growth performance in modern genetics through nutrition. Research and commercial experience have shown that it is possible to boost overall growth performance by up to 10%, simply by providing a more digestible diet during the first few days post-hatch (and perhaps beyond). Whether this is a favorable outcome depends on the cost of the feed, and in turn, that depends on ingredient selection.
Soybean protein remains the least expensive balanced protein for poultry, and this holds true for broiler super pre-starter feeds that are believed to be the main drive for boosting life-time growth performance. However, processed soybean products can be quite different. For example, normal soybean meal, albeit the least expensive source, is deemed unsuitable for feeding to young animals such as post-hatch broilers. Not only it contains too many anti-nutritional factors, but it retains in full its antigenic properties. Thus, other processed soybean products are required to overcome these problems.
Dry extruded soybeans offer one such balanced approach in terms of cost versus benefits. Once processed correctly, extruded soybeans can be devoid of antigenic properties, and contain minimal anti-nutritional factors, such as trypsin inhibitor activity. In addition, full-fat extruded soybeans offer the benefit of ‘protected’ oil that remains inside undisrupted cells; this is also due to the mixing of the naturally present antioxidant tocopherols. Thus, the risk of oxidation is minimized in such high-energy demanding feeds as broiler super pre-starters. However, the key to success remains the processing method, because not all extruders produce the same product.
A recent study from Iowa State University indicated that feeding high-shear dry-extruded partially-deoiled soy meal increased overall growth performance in broilers. See the table indicating overall growth performance of broilers fed extruded or raw grains (Meyer and Bobeck, 2020, Iowa State University Research Report). Many nutritionists would have anticipated such favorable results based on commercial experiences. But, even more interesting was the fact that dry-extruded corn provided a further boost in performance. Here, nutritionists would have anticipated very little benefit from feeding cooked corn to poultry. Feeding both grains in extruded form yielded the best overall effect. Based on this preliminary study, we may suspect that modern genetics have outpaced our nutritional thinking! Of course, more studies are required to answer the many questions raised by this straightforward study, but this is the hallmark of any good trial!