37 Revista CES Medicina Veterinaria y Zootecnia / Volumen 8 / Número 1 / enero – junio de 2013/ ISSN 1900-9607 Juan Miguel Gómez Urrego 1* , Zoot, cMSc; Sergio Andrés Yepes Jaramillo 2 , Ing Agron, MSc; Rolando Barahona Rosales s3 , BSc, MSc, PhD. *Autor para correspondencia: Juan Miguel Gómez Urrego. Universidad Nacional de Colombia, Calle 59ª No 63 – 20, bloque 50, Medellín, Colombia – Núcleo el Volador. E-mail: jmgomezu@unal.edu.co 1,3 Grupo BIOGEM, línea de investigación en nutrición animal, Facultad de Ciencias Agrarias, Universidad Nacional de Colombia Sede Medellín, Calle 59A No 63 - 20 bloque 50, Medellín, Colombia; 2 Setas Colombianas, Antioquia, Colombia. (Recibido: 3 de diciembre, 2012; aceptado: 3 de mayo, 2013) Abstract ¤ Para citar este artículo: Gómez Urrego JM, Yepes Jaramillo SA, Barahona Rosales R. Caracterización nutricional del residuo del cultivo de la seta Agaricus bisporus como alimento potencial para bovinos. . Rev CES Med Zootec. 2013; Vol 8 (1): 37-59. Nutritonal characterizaton of the crop residue of mushroom Agaricus bisporus as a potental feed for catle ¤ Caracterización nutricional del residuo del cultvo de la seta Agaricus bisporus como alimento potencial para bovinos Caracterização nutricional do resíduo da cultura do cogumelo Agaricus bisporus como alimento potencial para bovinos Each year, agriculture generates large amounts of lignocellulosic waste of low nutritional quality. This quality could be improved by the use of basidiomycetes. The aim of this study was to characterize the bedding residue from commercial cultivation of Agaricus bisporus as a feed for ruminants. Nutrient analyzes and mycotoxins content were performed. In situ degradation kinetics and in vitro gas production were also determined. The ash content decreased 9% and crude protein increased by 2.7% when the cover soil (peat) was removed from the bedding residue. In vitro degradability of dry matter at 72 hours was 8.4%. The peat-free bedding residue had 12.7, 29.1, 26.1, and 39.6% CP, NDF, ADF, and ash, respectively. This material contains most of the minerals required by cattle. A 76% of the nitrogen fraction is insoluble in borate-phosphate buffer, and 83% of the total nitrogen is of proteic nature. No detectable restrictive levels of mycotoxins were found. The ruminal DM effective degradation (DE) of the peat-free residue was 39.6%. This is 68% higher than the residue with peat for the time and accumulated gas at the infection point and at the maximum gas production rate. The high content of sulfur (2.1%) in the peat-free residue might limit its dietary inclusion for cattle to a maximum of 14%.