As more feed grade amino acids become available for formulation in broiler diets, the key challenge of meeting live performance and carcass traits as diet protein supply is lowered mimics the fundamental challenge of the past. Hence, the addition of each limiting feed grade amino acid in broiler diet formulation minimizes nitrogen excesses by closer meeting the most limiting amino acids in the nutrient matrix, but introduces concerns in terms of amino acid absorption, limitations of the less limiting essential or non- essential amino acids, or an imbalance of overall dietary protein and calories. Regarding the latter, as feed grade amino acids enter the ingredient matrix, soybean meal is reduced and birds consuming diets reduced in CP almost always exhibit an increase in peritoneal cavity fat. Is the associated increase in carcass adipose tissue a reflection of feed grade amino acid increased absorption resulting in bird imbalances, a reflection of more dietary grains (e.g., starch) resulting in an energy imbalance, a reflection of not adjusting dietary energy needs as protein supply is lowered, or a combination of the former? The understanding of dietary energy is compounded by the fact that commercial broilers are selected for leanness resulting in heightened responsiveness to amino acids as compared to that of energy. Recent research has focused on dietary variations of CP and net energy (NE). Ross 708 broilers were fed either 20.2 or 22.5% CP diets balanced with ME or NE from 7 to 32 d of age. Live performance and processing differences were minimal, but a CP x energy interaction occurred indicating that the increase in carcass fat caused by feeding reduced CP could be reversed with NE balance vs ME. Additional work demonstrated that Cobb broilers fed varying CP and NE from 31 to 41 d of age resulted in minimal interactions, but increasing NE decreased feed intake and feed conversion.
Article Quarter: FY23 Q4
Practical impacts of formulating in NE in broilers
Net energy (NE) in poultry is regarded as a more precise energy system compared to conventional apparent metabolizable energy (AME) due to its ability to consider the energy lost as heat increment from nutrient metabolism, which averages 25% of AME and is variable with feed characteristics. However, unlike pigs, NE is not yet implemented in poultry nutrition. A study was conducted to measure the NE value of 23 diets that were highly variable in terms of chemical composition (% dry matter; 33.6 to 55.3% for starch; 20.8 to 28.4% for crude protein (CP), 2.7 to 10.6% for fat (EE) and 7.0 to 17.2% for NDF) to establish NE prediction equations for broiler feeds. Diets were prepared with 13 major ingredients (wheat, corn, paddy rice, broken rice, cassava, full-fat soybean, soybean meal, canola meal, animal protein, rice bran, wheat bran, palm kernel meal, palm kernel oil) at various and independent inclusion levels to calculate robust prediction equations between NE content and analyte constituents of ingredients. All diets met the amino acid requirements of the birds. The diets were fed to male Ross 308 broilers kept in 12 open-circuit respiratory chambers from 17 to 22 days of age (4 birds per cage) after 5 days of adaptation for measurement of growth performance, diet AME content and heat production and calculation of diet NE value. Performance of birds (89 g/d BW gain on average), diet AME (3644 kcal/kg dry matter on average; range: 3356 to 4003) and AME/GE (79.4% on average) were as expected. The NE/AME ratio averaged 76.6% (range: 74.7 to 78.7%) and increased with EE and decreased with CP in the feed. Accordingly, diet NE value was positively related to AME and EE contents and negatively to CP level; NDF also had a significant negative contribution to NE content. Starch had no significant impact on NE prediction. The NE equations generated in the current study show good agreement with previous studies on poultry and pigs and were also able to predict the NE value of the ingredients in our trial. Validation of the NE equation proved that NE-based broiler diets reduced feed cost without negative impact on growth performance when compared to AME-based diets. A series of subsequent trials are scheduled to achieve the optimum NE level and respective inclusion of lysine, other essential amino acids, as well as crude protein. As NE system favors formulating low CP diets with supplementation of synthetic amino acids, it is also planned to check meat yield and carcass quality during the trials.
The NE values of the diets and ingredients of poultry: methodological approaches
The major cost of poultry feed is energy, accounting for more than 70% of the feed costs. Therefore, accurate formulation of feed energy with adequate ingredient energy values is paramount for the effective formulation of poultry feed. Currently, apparent metabolizable energy (AME) is still used to assess the available energy in ingredients and feed for poultry. However, the limitations of AME have been recognized since the 1940s. Net energy (NE), the energy system measuring the actual energy used for maintenance and production, is more accurate for the feed formulation to meet the requirement of the animals, which has been used in other animals such as ruminants and swine. In poultry, the use of the net energy system has been halted due to the difficulty in achieving accurate measurement of NE or, more exactly, the inability to predict NE for feed and ingredients. Also, the benefit of using NE vs AME has not been demonstrated on a large scale or conceptually accepted by many poultry nutritionists. Henceforth, there is a need to ensure the NE values are accurately measured and predicted so as to make the application of the NE system in poultry production realized in the near future. Herein, this presentation will discuss the approaches for the measurements or prediction of NE of diets and ingredients for poultry from a methodological point of view. The indirect calorimetric system, using both closed and opened circuit chambers, has been used to measure the heat production of animals. Then accurate NE values of diets can be achieved by simultaneously measuring the AME of the feed with a total excreta collection method. Potentially, the NE values of ingredients can also be measured, albeit caution must be made to avoid flawed design and calculations. The NE of ingredients and feed can be calculated with available prediction equations, such as those recently published, given the available key nutrient composition and AME values. Particular attention should be drawn to the accuracy of diet and ingredient AME values for such prediction, as AME accounts for a large proportion of the calculation for NE. The NE requirement levels for different poultry are another important aspect of implementing the NE in poultry in this presentation. In addition, the potential of using table values and near-infrared spectroscopy will also be discussed.
Impact of soybean processing expansions on product quality, quantity and supply chain for animal nutrition
The impact of federal and state environmental regulations is creating an unprecedented demand for renewable diesel as a mandated and tax credited fuel as a more sustainable replacement for biodiesel and other petroleum based fuels. The need for lower carbon intensity feedstock, in this case soybean oil, has encouraged U.S. soybean processors to dramatically increase the production capacity of soybean processing plants through expansions of existing plants and construction of new facilities throughout the corn belt. Additionally, the new initiatives have forced a marriage of petroleum refiners and soybean processors to provide the new fuels. Renewable Diesel is a one-for-one, drop-in replacement for current diesel fuel and has the same physical characteristics as petroleum diesel, requiring no adjustments to engines, using 100% renewable fats and oils.
Economic evaluation of soybean meal and the challenge of supply chain
The soybean supply chain incentivizes upstream participants to maximize crop yield (volume), while downstream participants (nutritionists) make decisions based on crop quality characteristics such as amino acid concentration and energy content. These parameters tend to decline as soybean yield increases, consequently, the value proposition for soybean meal (SBM) is not fully recognized in the market. Furthermore, on a global basis, SBM sales are based primarily on minimum crude protein (CP) content, which does not fully account for the true value of SBM to the end user. To demonstrate the application value of SBM and its nutrient composition, SBM value was quantified in both poultry and swine diets using the nutritional attributes (digestible amino acids and energy) that are the primary determinants of end-user value.
Amino acid levels and energy specifications in soybean meal for poultry and pigs
Soybean meal (SBM) is the most widely used ingredient source of amino acids for pig and poultry diets in the world. Accurate diet formulation with soybean meal (SBM) requires reliable amino acid and energy values, but net energy (NE) estimates in international references are underestimates. SBM amino acid and energy (metabolizable energy and NE) content for poultry and pigs were expressed relative to SBM protein level over the 44.0 to 48% range since both increase as SBM and crude protein increase.
Counteracting roles of lipidic aldehydes and phenolic antioxidants on soy protein oxidation defined by a chemometric survey of solvent and mechanically extracted soybean meals
Soybean meal (SBM) is a premier source of protein for feeding food-producing animals. However, its nutritional value can be compromised by protein oxidation. In this study, a total of 54 sources of solvent extracted SBM (SSBM) and eight sources of mechanically extracted SBM (MSBM), collected from different commercial producers and geographic locations in the United States during the years 2020 and 2021, were examined by chemometric analysis to determine the extent of protein oxidation and its correlation with soybean oil extraction methods and non-protein components. The results showed substantial differences between SSBM and MSBM in the proximate analysis composition, protein carbonyl content, lipidic aldehydes, and antioxidants, as well as subtle differences between 2020 SSBM and 2021 SSBM samples in protein oxidation and moisture content. Correlation analysis further showed positive correlations between protein carbonyl content and multiple lipid parameters, including the ether extract, p-anisidine value, individual aldehydes, and total aldehydes. Among the antioxidants in SBM, negative correlations with protein carbonyl content were observed for total phenolic content and isoflavone glycoside concentrations, but not for Trolox equivalent antioxidant capacity (TEAC), α-tocopherol, and γ-tocopherol.
Environmental impacts of eco-nutrition swine feeding programs in spatially explicit geographic regions of the United States
This study was conducted to determine greenhouse gas (GHG) emissions, water consumption, land use, as well as nitrogen (N), phosphorus (P), and carbon (C) balance of five diet formulation strategies and feeding programs for growing-finishing pigs (25–130 kg body weight) in the three spatially explicit geographic regions where the majority of U.S. pork production occurs. Feeding programs evaluated consisted of 1) standard corn-soybean meal (CSBM) diets, 2) CSBM containing 15% corn distillers dried grains with solubles (DDGS), 3) CSBM with 8.6% thermally processed supermarket food waste (FW), 4) low crude protein CSBM diets supplemented with synthetic amino acids (SAA), and 5) CSBM with phytase enzyme (PHY) added at 600 FTU (phytase units)/kg of diet. An attributional Life Cycle Assessment approach using a highly specialized, spatially
explicit Food System Supply-Chain Sustainability (FoodS3) model was used to quantify GHG emissions, water consumption, and land use of corn, soybean meal, and DDGS based on county level sourcing. The DDGS, FW, and SAA feeding programs had less estimated N and P intake and excretion than CSBM, and the PHY feeding program provided the greatest reduction in P excretion. The FW feeding program had the least overall GHG emissions (319.9 vs. 324.6 to 354.1 kg CO2 equiv./market hog), land use (331.5 vs. 346.5 to 385.2 m2/market hog), and water consumption (7.64 vs. 7.70 to 8.30 m3/market hog) among the alternatives. The DDGS feeding program had the greatest GHG emissions (354.1 kg CO2 equiv./market hog) among all programs but had less impacts on water consumption (7.70 m3) and land use (346.5 m2) per market hog than CSBM and PHY. The SAA feeding program provided a 6.5–7.4% reduction in land use impacts compared with CSBM and PHY, respectively. Regardless of feeding program, the Midwest had the least contributions to GHG emissions and land use attributed to feed and manure among regions. Water consumption per market hog associated with feeding programs was much greater in the Southwest (59.66–63.58 m3) than in the Midwest (4.45–4.88 m3) and Mid-Atlantic (1.85–2.14 m3) regions.
