The Animal agriculture industry is faced with serious and multi-faceted challenges resulting in steep increases in operational expenses. Feed costs, which constitutes 65 – 78 % of total operational costs depending on the species, type of operations, and feeding strategy are most severely affected. Ingredient costs and availability, consistency in quality, global logistical issues and increased shipping costs, higher cost of fuel, energy and raw materials, and a drop in demand and/or market prices are taking heavy tolls that might result in some major changes in market dynamics and future of the industry, with more profound effects on small and medium size operations.
In many cases, the initial reaction to such dramatic changes in ingredient prices and consequently higher feed cost, is the elimination of feed additives in order to reduce cost of feed i.e. cost per tonne of feed produced. This practice, in fact might give an opposite outcome in terms of efficiency and Return On Investment (ROI). The unwanted and/or unforeseen outcome of such reactive decisions could be higher Feed Conversion Ratio(FCR), lower Average Daily Gain (ADG), longer production cycles, and higher Feed Intake (FI).
There are a number of potential solutions, both short term and long term to cope with increased costs and take proper steps to alleviate the pressure and recover some of levels of costs. One such opportunity would be to reformulate the feed ingredients (based on availability and practical applications) and apply maximum levels of enzyme matrix values to achieve best ROI. As a part of a general efficiency improvement and consequently feeding strategy, the use of low protein diets (potentially with incorporation of alternative ingredients) and application of proper enzyme combinations at optimal dose levels, and more importantly implementing matrix values would be a very viable, practical, and beneficial approach. Feeding strategy plays a critical role in coping with such situations but the diet formulation is only one piece of the puzzle.
Low Protein diets i.e. diets with diluted levels of Crude Protein (CP) and hence amino acids, might be a practical solution if applied properly. Feeding a low crude protein (CP) diet fortified with individual amino acids (AA) is one of the strategies which can bring down feed cost. Apart from being able to sustain performance it may also reduce N excretion into the environment thus reducing the environmental footprint from animal agriculture.
There are many references regarding application and practical implementation of low protein diets and most point out that some special considerations must be taken into account. These include amino acid balance and ratios that might differ from benchmark or routine CP levels and ratio of CP to Energy, ingredient levels especially corn and wheat, and overall feeding strategies and application of enzymes and additives.
The genotype of modern broiler breeds ensures a faster growth rate and body weight gain (BWG) and improved FCR and this requires supply of highly digestible protein sources. In practice, most diets are formulated with some level of “additional margin” that results in over feeding nutrients such as protein. This additional or undigested fraction can cause shiftsand imbalance in the existing microbiota leading to gastrointestinal disorders or diseases.
Limited availability of all crystalline AA at a commercially feasible price may force a proportionate reduction in overall AA density when a low CP diet is formulated, and this may result in inconsistent performance. The more deficient the non-essential AA (NEAA) are the greater will be the shunting of the essential AA (EAA) to the process of NEAA synthesis thus limiting the supply of the former to the process of BW gain. Increasing AME supply, however, should increase protein accretion, although up to a genetically predefined point, and supply of AME beyond this point would merely translate into an excess of body fat. Although the aforementioned level of dietary AME is difficult to define precisely, available data suggest that the optimum level of AME in diets is lower than what is being fed commercially. These findings allow feed formulators to marginally bring down the density of some critical nutrients without compromising performance significantly.
Exogenous enzymes like phytase as well as xylanase, amylase and proteases either independently or in combination (XAP) serve as an adjunct to this approach whilst imparting profit to the feed cost.
The effects of phytase in improving calcium (Ca) and phosphorus (P) digestibility have been well documented as well as improvements in amino acid and energy digestibility. Increasing the inclusion level of phytase has shown potential to elicit more pronounced improvement in apparent ileal digestibility (AID) of AA though the possibility of a diminishing return beyond 1000 FTU/kg was not ruled out by these authors and it is shown that higher dose levels calculated based on diet specifications can be advantageous.
Supplementation of xylanase into corn-based diets reportedly increased fat and starch digestibility by facilitating digestion of resistant starch and improving access to cell walls via reduction in cell wall integrity, and/or modification of intestinal microbial communities through the production of prebiotic-like oligosaccharides. Combining phytase with XAP has reportedly spared up to 100 kcal AME/kg in broiler diets.
The amino acids released by the purported extra-phosphoric effects of phytase achieved with beyond the commercially practiced dosing regimens a proportionate amount of AME release is necessary which is possible if the level of xylanase or XAP is increased in diets. In recent studies the use of full matrix values (mineral, energy, and AA levels) were examined and proved to be a viable and practical strategy and the application of full matrix values of combined enzymes (Phytase + XAP) was proven in the effects of phytase and XAP at higher than the commercially practiced levels of inclusion either alone or in combination on performance and key metabolic indices in broiler chickens fed diets which were reformulated to contain (as per the combined matrix of the phytase and the XAP) 3% lower CP (and AA) and 120 kcal/kg less AME from 1-42 d period.
In summary, the animal agriculturecan partially overcome current challenges by adopting lower protein diets combined with optimized dosing of phytase and non-phytase enzymes without negative impacts on animal welfare or performance. We believe that continuous investment in animal studies to demonstrate these concepts under practical conditions is important to support our customers in the adoption of these and other concepts that drive sustainability and profitability for the livestock industry.
