Commercially Processed Former Foodstuffs in Poultry Diet: A Multidisciplinary Approach

The sustainability of livestock production is a critical challenge due to climate change, food security concerns, and feed-food competition. Former foodstuffs have gained attention as alternative feed ingredients under circular economy principles. This PhD project evaluates the impact of incorporating commercially processed former foodstuffs (cFF) as partial substitutes for conventional feed ingredients (corn, soybean meal, and soybean oil) in broiler diets. A literature review (2016–2022) provides insights into the inclusion of former foodstuffs in livestock diets, highlighting potential benefits and research gaps. A survey of 136 Italian livestock veterinarians was conducted to assess their attitudes toward former foodstuffs use in farm animals. Results showed that 90% of veterinarians were willing to adopt Former foodstuffs, though perceptions varied by gender and age. An experimental study was conducted with 200 one-day-old male ROSS-308 broiler chicks, which were allocated to four dietary groups (five replicates of ten birds per replicate) according to their average body weight (BW, 38.0 ± 0.11 g): a control diet (cFF0) and three experimental diets where corn, soybean meal, and soybean oil were replaced with 6.25% (cFF6.25), 12.5% (cFF12.5), or 25% (cFF25) cFF for 33 days. The experimental study utilized a two-phase feeding program, consisting of a starter phase (days 1–12) and a grower phase (days 12–33). The study evaluated various parameters including growth performance, apparent total tract digestibility, hematobiochemical traits, slaughter performance, meat physiochemical properties, meat quality and shelf-life under refrigerated storage, gut histomorphology, caecal microbiota composition, and caecal fermentation products. The results revealed no negative impact on growth performance, with feed efficiency improving as cFF level increased. Gut health remained unaffected, and meat physicochemical and sensory properties were unchanged, though alterations in fatty acid composition were noted. Microbiological analysis of refrigerated meat storage showed an improved shelf-life in the higher cFF inclusion groups. Additionally, ammonia concentration decreased with higher cFF levels, suggesting potential environmental benefits. These findings demonstrate that incorporating up to 25% cFF in broiler diets is a viable strategy without compromising broiler performance, meat quality, or gut health. This research contributes to sustainable livestock production by addressing feed-food competition and promoting circular economy practices. Further studies are recommended to refine optimal substitution levels and assess long-term implications in commercial production systems.