Improving sustainability in autochthonous slow-growing chicken farming: Exploring new frontiers through the use of alternative dietary proteins

Feed constitutes a crucial aspect of the environmental footprint within the livestock sector. Therefore, the development of novel feed formulations holds the potential to mitigate its impact. In this study, 96 birds from an autochthonous Italian dual-purpose chicken breed (Bianca di Saluzzo) were divided into two groups subject to different dietary treatments: one group was fed a conventional standard diet, while the other received an experimental soybean meal-free diet. The objective was to study the growth performance, blood traits, slaughtering performance, and meat quality of this breed raised under the two treatments and to identify the best slaughtering age. In addition, a life cycle assessment approach was used to study the environmental impact of the two diets. The results of the study are reported relative to 1 kg of live weight and 1 kg of ready-to-cook carcass. The results showed no differences in growth performance, slaughter performance, or blood traits between the two experimental diets, with the lowest feed conversion ratio recorded at the youngest slaughter age of 147 days (vs 174 days) (p < 0.05). The study also revealed the environmental impact of the experimental soybean meal free diet to be significantly lower than that of the conventional diet for all the considered parameters (impact of CO2 on human health, ecosystems, and resources) (p < 0.05). The results indicated 147 days as the most appropriate slaughter age for this breed, which also took into consideration the lower environmental impact at this age compared with a slaughter age of 174 days.