Impact of high-protein distiller's dried grains with solubles (HP-DDGS) on early growth benefits and carcass quality trade-offs in pigs

Despite the limited adoption of DDGS in South America, its potential benefits in pig nutrition have not been thoroughly evaluated, we assessed the effects of increasing levels of HP-DDGS in corn/soybean meal-based diets fed to pigs from the initial I nursery phase to the finishing phase on performance, health parameters, and quality characteristics of carcass, pork, and belly. Five hundred piglets were distributed in randomized blocks to five HPDDGS inclusion levels. HP-DDGS was introduced 14 days into the experiment and maintained until the end of the 147-day experimental period. It replaced corn and soybean meal in isoenergetic diets at increasing levels of 0 %, 10 %, 20 %, 30 %, and 40 %. Increasing levels of HP-DDGS positively affected average daily feed intake (P = 0.001), average daily gain (P = 0.0002), and body weight (P = 0.0003) in the nursery phase, while in the growing and finishing phase negatively impacted feed conversion ratio (P = 0.002 and P < 0.0001, respectively) and body weight (P = 0.018 and P = 0.0003, respectively). HP-DDGS inclusion also positively influenced fecal score; animals fed 40 % HP-DDGS in the nursery phase and 30 % and 40 % HP-DDGS in the growing and finishing phase had highest proportion of well-formed feces (fecal score 1), while those fed 10 % or no HP-DDGS showed more mild diarrhea (fecal score 2) (P < 0.0001 to P = 0.0024). Increased HP-DDGS inclusion levels had a negative impact on body weight at slaughterhouse (P < 0.0001), hot carcass weight (P < 0.0001), chilled carcass weight (P < 0.0001), backfat thickness (P = 0.042), belly weight (P = 0.0002), belly thickness (P < 0.0001), belly external flexibility (P < 0.0001), belly internal flexibility (P < 0.0001), and a* color component (P = 0.037), but had a positive effect on L* color component (P = 0.044). Overall, increased HP-DDGS levels in pig diets modified the fatty acid profile of belly fat. Although this belly fat shows increased oxidation rates and flexibility, it is rendered more suitable for human consumption in terms of health benefits. In this sense, including HP-DDGS in pig diets benefits early growth by improving gut health and reducing diarrhea, enhancing weight gain and fecal consistency. However, high HP-DDGS inclusions levels negatively affected carcass traits. While HP-DDGS improved the polyunsaturated lipid profile of pork, its overall impact on meat quality varied. Therefore, HP-DDGS should be used early in growth, with a transition to a low-fiber diet during finishing to mitigate these effects.