Le piume di pollo idrolizzate: un modello di filiera sostenibile nel mercato del petfood. Formulazione, preparazione e validazione di mangimi innovativi mediante lo studio delle performance, del microbiota fecale e della digeribilità apparente dei nutrienti in cani adulti.

Introduction: Growing interest in sustainability within the pet food sector has increased the demand for alternative protein sources derived from animal by-products, aligned with circular economy principles. Hydrolysed feather meal (HFM) represents a promising option due to its high availability, though it is characterised by nutritional limitations and moderate biological value. While hydrolysis enhances amino acid availability, the digestibility of HFM remains variable, and its effects on gastrointestinal health and colonic fermentation in dogs are not yet fully understood. Aim: These studies evaluated the impact of a diet containing HFM compared with a poultry meal (PM)-based diet on dog performances, faecal quality, fermentation metabolites, and, additionally, on the composition and stability of the intestinal microbiota. Materials and Methods: Two complete extruded diets were tested: a test diet containing 7% HFM and a reference diet based on PM, formulated with similar ingredients, additives, and nutrient profiles. To assess animal performance (BW, BCS, MCS, FCS), digestibility, faecal characteristics (organic acids and biogenic amines), and microbiota composition, two trials were conducted. Trial 1: A cross-over study was performed on six adult female English setter dogs allocated into two homogeneous groups. The experimental design consisted of two 45-day feeding periods (R1 and R2), separated by a 30-day washout and preceded by a 7-day dietary adaptation. Trial 2: A second study was carried out on eight adult English setter dogs (four females and four males), divided into two homogeneous groups: treated (TRT) and control (CTR) groups. The experimental design consisted of a 45-day feeding period. Discussion: The inclusion of 7% HFM was well accepted and did not impair animal performance. Faecal consistency remained within the optimal range, and concentrations of organic acids and biogenic amines indicated the maintenance of gastrointestinal health. Microbiota analysis showed diet-related shifts in specific bacterial taxa; however, overall microbial diversity and composition remained consistent with a healthy intestinal ecosystem. Conclusions: In conclusion, partial replacement of poultry meal with hydrolysed feather meal did not negatively affect dog performances, faecal quality, microbial metabolites, or gut microbiota balance, supporting the potential of HFM as a sustainable alternative protein source in canine nutrition. Further research is needed to investigate digestibility, the influence of different processing methods, and dose–response effects. This research was supported by the Project “BIO = C = O”, PON-MISE I&C 2014–2020 FESR, ASSE 6 REACT Priorità di investimento 13.i Azione I, funded as part of the European Union’s response to the COVID-19 pandemic. Project codex N. F/200078/03/X45, CUP B41B20000280005.