Abstract Dried Distillers Grains with Solubles (DDGS), co-products from the ethanol industry, represent a sustainable and cost-effective alternative in swine nutrition. However, variations in composition and fiber content may influence nutrient digestibility and animal performance. This study evaluated the effects of increasing inclusion levels of Brazilian DDGS and a high-protein dried distillers grains (HP-DDG) source on growth performance and economic viability of growing–finishing pigs under commercial conditions. A total of 720 pigs (360 immunocastrated males and 360 females; initial body weight of 20.2 kg) were allotted to a randomized complete block design comprising five dietary treatments: 0% (T1), 15% (T2), 25% (T3), and 35% (T4) DDGS, and 25% HP-DDG from a different source (T5). Each treatment consisted of 12 replicates with 12 pigs per pen. Diets were formulated according to the nutritional recommendations of the Brazilian Tables for Poultry and Swine (2024) and provided ad libitum for 97 days, divided into five feeding phases. Individual body weight and feed intake were recorded to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR). The economic evaluation included feed cost, revenue from body weight gain, and gross profit. Data were analyzed using mixed models in RStudio (version 4.2.1), and treatment means were separated by Tukey’s test at P ≤ 0.05. From d 0–97, pigs fed 15% DDGS (T2) had the greatest ADG (1.07 kg/d; P 0.001) and an FCR (2.28) comparable to the control (T1). Increasing DDGS inclusion above 25% increased ADFI (2.52 and 2.49 kg/d for T3 and T4, respectively) and impaired FCR (2.37–2.41; P 0.001). The HP-DDG diet (T5) resulted in the lowest ADG (1.02 kg/d; P 0.001) and the lowest feed intake among treatments. Consequently, pigs fed HP-DDG reached a final BW of 118.84 kg, whereas pigs fed 15% DDGS reached 124.31 kg, representing a difference of approximately 5.47 kg at the end of the experimental period. Economic evaluation revealed that total feed cost was higher for diets containing DDGS, whereas the lowest feed cost was observed for the HP-DDG diet. However, gross revenue per total weight gain was greatest for the 15% DDGS treatment (USD 172.19), while HP-DDG resulted in the lowest value (USD 163.16). Overall, the highest gross profit was observed for pigs fed 15% DDGS (≈ USD 83.94/head; P = 0.038), comparable to the control and superior to HP-DDG. DDGS can be included at levels up to 25% without compromising growth performance, whereas a 15% inclusion provided the best economic return. Higher inclusion levels increased feed intake and worsened feed conversion ratio. Although the HP-DDG diet reduced total feed cost, this was primarily associated with the lower feed intake observed for this treatment, which consequently resulted in reduced growth performance and lower overall profitability. Nevertheless, further studies evaluating additional inclusion levels are required to better define strategies for efficient HP-DDG utilization in swine diets. These findings highlight the nutritional, economic, and sustainability potential of DDGS as a coproduct that converts ethanol industry residues into animal protein.
Motta et al. (Wed,) studied this question.