Variability in Nutrient Measurement of Feed Ingredients Compromises Profitability in the Australian Poultry Industry

Feed accounts for more than 65% of poultry production costs; thus, accurate feed formulation is vital to ensure poultry are receiving an optimal diet and nutrients are not in under- or oversupply. However, this is difficult when the nutrient specifications of feed ingredients are highly variable. In order to help reduce this variability, appropriate sampling methodology is critical. Nevertheless, recommended methodology and depth of detail within technical articles varies greatly and does not always reflect the recommendations of the AOAC, a non-profit scientific association that publishes standardised analytical methods. This has been an ongoing issue for some time; 45 years ago Lerman and Bie (1975) concluded that improper sampling technique is a major component of ingredient variability. Nevertheless, few animal nutrition studies report the sampling technique used, nor is the potential economic cost of variability often discussed. Protein is an expensive and crucial macronutrient component of poultry diets; thus, the extent that variation in protein in feed ingredients affects expected performance and profits for the Australian poultry industry was modelled.

Standard Australian wheat-SBM-canola meal-based starter, grower, finisher and withdrawal diets were formulated and profitability modelled using EFG Broiler Model software (EFG Software, 2020). The variability (coefficient of variation; CV) in crude protein of the components of Australian poultry diets were estimated from Moss (2020), and simulations were performed to estimate the likelihood a diet would fall below nutrient recommendations using Excel 2016, NORMINV function (10,000 simulations/diet). All prices are in $AUD. CV’s grew larger in finisher and withdrawal diets compared to starter and grower diets, and wheat was the single greatest source of variability in crude protein content of diets. Within withdrawal diets formulated to 19.2 g/kg crude protein from book values, there is approximately a 10% probability (or one in 10 diets) that it will fall below 182 g/kg CP, and diets may fall as low as 162 g/kg CP; which was modelled to lower the gross margin from $21.26/m2 ($1.417/bird/cycle) to 7.88/m2 ($0.525/bird/cycle) − a reduction in profits of 63%. Therefore, it is possible to incur a difference of up to $26,753 in gross margin from one cycle of 30,000 broilers by simply overestimating the nutrient content of feedstuffs. Hence, it is clear that identifying the most accurate way to sample, and improving the understanding and implementation of proper sampling methodology, is of great importance for the Australian poultry industry.

ACKNOWLEDGEMENTS: The authors would like to acknowledge and thank Poultry Hub Australia for funding this project and for their guidance, encouragement and support.