When it comes to co-products, People always associate them with rubbish. There is no denying the fact that large amounts of co-products from agro-industrial plants has not been reasonable and adequate use, and are wasted. For this reason, this problem has attracted attention from the scientists, government and enterprises worldwide. They have made great efforts in their own aspects to deal with this problem. Importantly, rational utilization of co-products is propitious for saving of resources and thus brings a great benefit to our society.

In recent years, using coproducts from agro-industrial plants to replace substantial amounts of cereal grains and protein-rich plant feedstuffs in swine diets has become a very attractive approach to reduce feed cost. Majority of these coproducts have high energy and nutrient contents, albeit high antinutritive contents. Ethanol production from cereal grains yields a coproduct, distillers dried grain with solubles (DDGS), which can be used as an alternative feedstuff in swine diets because of its high protein, amino acids (AA) and crude fat contents in relation to its corresponding grain. Corn is the major feedstock for ethanol production in USA and eastern Canada, whereas wheat is the main feedstock for ethanol production in western Canada and Europe. Additionally, the new generation DDGS have higher digestible (DE) and metabolizable energy (ME) and digestible AA contents compared with DDGS produced from the older and more traditional ethanol plants. However, it is not known whether nutrient digestibility and pig growth performance will remain the same if graded levels of wcDDGS are added to swine diets that have similar calculated net energy and digestible nutrient values.

Using 48 pigs with an average body weight [BW] of 25.5 kg, a team of researchers from University of Manitoba, and Institute of Subtropical Agriculture, the Chinese Academy of Sciences design experiments to determine the effects of increasing wheat-corn-derived distillers dried grains with soluble (wcDDGS) (1:1 wheat to corn ratio) content in grower diets on performance and apparent total tract digestibility (ATTD) of energy and nutrients.

The researchers found that adding 30% wcDDGS to grower diets will not adversely affect feed intake, implying that voluntary feed intake by growing pigs may not be negatively affected when up to 30% of wcDDGS is included in their diets. However, growth rate of the pigs was hampered by increasing dietary levels of wcDDGS even though the wcDDGS-containing diets were formulated to contain similar calculated NE and digestible nutrients as the control diet. Thus, the risks of high dietary wcDGGS content may not be completely alleviated by formulating growing pig diets on the basis of NE and SID AA systems.

This research was jointly supported by Husky Energy, Agri-Food Research and Development Initiative, Manitoba, Canada, Western Economic Diversification Canada (WED), Manitoba Pork Council, and the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (Grant No. 2011T2S15)

The study entitled “Effects of formulating growing pig diet with increasing levels of wheat-corn distillers dried grains with solubles on digestible nutrient basis on growth performance and nutrient digestibility” has been published in Volume 98, Issue 4, August 2014 of Journal of Animal Physiology and Animal Nutrition, details could be found at http://dx.doi.org/10.1111/jpn.12112.