Utilizing Brown Mushroom Stem Waste as an Eco-Friendly Alternative to Soybean Meal in Layer Chick Nutrition

Ahmed A.A. Abdel-Wareth¹Kayla G Stamps¹Md Salahuddin¹Venkatesh Balan²Maedeh Mohammadi²Woo Kyun Kim³Weihang Zhu²Ahmed A Ahmed¹Cassandra D Gray¹Adrian M W Aviña¹Taylor Rounds-Carter¹Trahmilla L Carr¹Amri Williams¹Adebowale Bakare¹Jayant Lohakare^1*

• ¹Prairie View A&M University, Prairie View, United States
• ²University of Houston Cullen College of Engineering, Houston, United States
• ³University of Georgia, Athens, United States

Objectives: This study evaluated the potential of brown mushroom stem (BMS) powder as a sustainable feed ingredient in poultry diets by assessing its effects on growth performance, health status, and environmental impact. The study involved 160 three-week-old Lohmann LSL Lite chicks. After a four-day adaptation period on the control diet, the chicks were assigned to four dietary groups: 0% (control), 2%, 4%, and 6% BMS of replacing soybean meal. BMS were sourced from a local commercial mushroom producer. The stems were cleaned, washed, and freeze-dried. The freeze-dried BMS were then finely ground into powder for inclusion in the chicken feed. Each group consisted of five replicates, and each replicate had eight chicks. Feed intake and growth performance were recorded weekly over a five-week duration in a cage system. Gas emissions from excreta were measured using a sensor-based system. At the end of the study, randomly selected birds were slaughtered for blood and organ collection for further analysis. Polynomial contrasts were used to analyze the linear and quadratic effects of increasing levels of BMS powder. The results showed no significant (P<0.05) differences in final body weight, weight gain, feed intake, and feed conversion ratio (FCR) among groups. Internal organ weight also showed no significant (P<0.05) difference among groups, indicating the safety of BMS powder incorporation in chick diets. Blood biochemical parameters, including total protein, globulin, aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), uric acid, and cholesterol, exhibited both linear (P<0.05) and quadratic (P<0.05) effects. Interestingly, gas emissions, including carbon dioxide (CO₂), ammonia (NH₃), and methane (CH₄), measured on days 31 and 32 of the experiment, exhibited significant quadratic responses (P < 0.05) to increasing levels of BMS powder in the diet. While these effects were modest and limited to a short observation window, they suggest a potential short-term environmental benefit that warrants further investigation. These results indicate that BMS powder inclusion may positively influence certain biochemical markers and reduce the environmental footprint of poultry production. Future research should validate these findings in commercial settings and explore their long-term applications for broader adoption in eco-friendly production systems.