Sfericase protease, phytase, and xylanase combination improves body weight, feed conversion rate, ileal digestibility, and gut morphology in broilers

Froylán Abraham Rodríguez Soriano ^1* CARLOS LOPEZ COELLO ^1* Ernesto Avila -Gonzalez ^1* Jose Arce-menocal ^2* Silvestre Chárraga Aguilar ^3* Vitor Fascina Barbosa ^4*

• ¹ National Autonomous University of Mexico, México City, Mexico
• ² Michoacana University of San Nicolás de Hidalgo, Morelia, Michoacan, Mexico
• ³ Other, El Salto, Mexico
• ⁴ Other, SAO PAULO, Brazil

This study aimed to evaluate the effects of a novel sfericase protease-an endopeptidase from the serine protease family, subtilisin subfamily A (MEROPS ID S08.113)-combined with a phytase and xylanase, on broiler performance, gut morphology, litter quality, and ileal digestibility. Cobb 500 male chickens (n = 1,800) were randomly allocated to 36 pens in four treatments with nine replicates (50 chicks each) until 42 days of age.Treatments included: a positive control (PC, diet following adapted Cobb nutritional recommendations, aligned with Commercial Broiler Production Systems); a negative control (NC, with average reductions of 0.500% in crude protein, 0.041% in digestible lysine, 0.040% in digestible methionine + cysteine, 0.049% in digestible threonine, and 0.032% in digestible arginine compared with the positive control); NC supplemented with 10,000 new feed protease units (NFP)/kg feed; and NC supplemented with 30,000 NFP/kg feed. Diets, provided in mash, consisted of corn, soybean meal, canola meal, distiller's dried grains with solubles, meat and bone meal, corn gluten meal, and soybean oil. At 42 days of age, NC caused lower body weight compared to PC and protease-supplemented groups (p < 0.05). The worst feed conversion was obtained under the NC, significantly different from the PC and NC + 10,000 NFP/kg (p < 0.05). Gut morphology analysis revealed significant differences in villus length and number, crypt depth, and surface among treatments (p < 0.05), with the NC exhibiting the lowest surface area per µm². Energy digestibility was lowest in the PC group, while proteasesupplemented groups (NC + 10,000 and 30,000 NFP/kg) showed the highest digestibility values (p < 0.05).Improvements in energy and nitrogen digestibility correlated significantly with body weight, feed conversion, and gut morphology (p < 0.05). These findings demonstrate that the addition of sfericase protease, combined with phytase and xylanase, positively influences broiler body weight, feed conversion, gut morphology, and nutrient digestibility, providing practical benefits when enzyme inclusion is optimized based on diet composition and ingredient quality.