Characterization of Dietary Energy in Swine Feed and Feed Ingredients: A Review of Recent Research Results

Abstract

Feed is single most expensive input in commercial pork production representing more than 50% of the total cost of production. The greatest proportion of this cost is associated with the energy component, thus making energy the most important dietary in terms of cost. For efficient pork production, it is imperative that diets are formulated to accurately match dietary energy supply to requirements for maintenance and productive functions. To achieve this goal, it is critical that the energy value of feeds is precisely determined and that the energy system that best meets the energy needs of a pig is used. Therefore, the present review focuses on dietary supply and needs for pigs and the available energy systems for formulating swine diets with particular emphasis on the net energy system. In addition to providing a more accurate estimate of the energy available to the animal in an ingredient and the subsequent diet, diets formulated using the this system are typically lower in crude protein, which leads to additional benefits in terms of reduced nitrogen excretion and consequent environmental pollution. Furthermore, using the net energy system may reduce diet cost as it allows for increased use of feedstuffs containing fibre in place of feedstuffs containing starch. A brief review of the use of distiller dried grains with solubles in swine diets as an energy source is included.

Host-Microbiota Interactions in Ileum and Caecum of Pigs Divergent in Feed Efficiency Contribute to Nutrient Utilization

“…Considering the high energy concentration and low fiber content of commercial pig diets, it is expected that the main turnover of these diets takes place in the proximal parts of the gut [30,31]. Accordingly, the composition of the intestinal content, which remains after passing the proximal intestine, is likely to be of limited complexity regarding microbially digestible material, thereby affecting the microbial colonization and diversity in the ileum and caecum.…”

Production performance of pigs reared in different systems and fed increased energy content diets with or without green alfalfa

“…Because energy is the single most expensive component of a pig diet, optimizing its utilization is critical for efficient pork production (Velayudhan et al, 2015).…”

Co-products in maize-soybean growing-pig diets altered <i>in vitro</i> enzymatic insoluble fibre hydrolysis and fermentation in relation to botanical origin

“…Starch and fat were theoretically most displaced by targeting feed fermentable fibre, which was demonstrated in the HF/LF diets. Given the high fibre, dietary energy should ideally be quantified in net energy terms to accommodate fibre-specific energy wastage (Noblet & Le Goff., 2001;De Lange et al, 2010;Gao et al, 2015;Velayudhan et al, 2015). Similarly, a truly digestible essential amino acid approach accounts for fibrespecific endogenous amino acid wastage (Zhu et al, 2005;Libao-Mercado et al, 2006;, and for the trade-off between fermentative loss (Columbus et al 2010), and microbial synthesized digestible amino acids (Torrallardona et al, 2003;Zhu et al, 2005;Libao-Mercado et al, 2009).…”