Effects of Pleurotus sapidus (Schulzer) Sacc. treatment on nutrient composition and ruminal fermentability of barley straw, barley rootless, and amixture of the two

Alfonso Soto-Sánchez1, J. Efrén Ramírez-Bribiesca1*, Marcos Meneses-Mayo2, Octavio Loera-Corral3, Luis A. Miranda-Romero4, and Ricardo Bárcena-Gama1
Barley (Hordeum vulgare L.), and its derivatives, ranks fourth in cereal production worldwide, and the Pleurotus species are among the most efficient types of lignocellulolytic white-rot fungi. The objective of this research study was to evaluate the degradation of barley straw and barley rootless with an inoculum of Pleurotus to improve their nutritional availability as a food source for ruminants. Two experiments were conducted; the first was to determine the effects of inoculation of Pleurotus sapidus (Schulzer) Sacc. (PS) in barley (Hordeum vulgare L.) straw (BS), barley rootless (BR), and a 75% BS and 25% BR mixture (M).The second experiment was to evaluate the same substrates in vitro ruminal fermentation. Barley rootless had better organic matter (OM) degradability than BS after 24 h incubation with PS. The protein content in BR was higher than in BS (P < 0.01). Enzyme activities had the highest concentration from the start of fermentation, and in vitro dry matter (DM) degradability in BS and BR increased after 8 and 24 d fermentation, respectively (P < 0.05). Propionic acid concentration was enhanced after 16 d fermentation in BR (P < 0.5). The use of BS combined with BR exhibited better fermentation; this result provides relevant information for integrating BR with other substrates and improving the use of straw, which can be more nutritionally available for feeding ruminants.
Keywords: Barley, in vitro fermentation, enzyme activity.
1Colegio de Postgraduados, Campus Montecillo, km 36,5 Carr. México-Texcoco, CP56230, Texcoco, México. *Corresponding author (efrenrb@colpos.mx).
2Universidad Anáhuac, Facultad de Ciencias de la Salud, Av. Universidad Anáhuac 46, CP 52786, Huixquilucan, México.
3Universidad Autónoma Metropolitana, Unidad Iztapalapa, Departamento de Biotecnología, Av. San Rafael Atlixco 186, Vicentina, Iztapalapa, 09340 Ciudad de México, México.
4Universidad Autónoma Chapingo, Departamento de Zootecnia, km 38,5 Carr. México-Texcoco, CP 56230, Texcoco, México.