Effect of incorporating fungal-media residue in bedding on domestic-pig growth performance and welfare in winter

Bedding materials significantly affect the health and growth performance of domestic pigs. The residue media from mushroom cultivation has potential as pig bedding because of its nutrient content for microbes and low cost. However, its components and granularity are heterogeneous. The present study investigated the effect of beddings containing fungal-residue media on the growth performance, stress response, thermoregulatory behaviour and general welfare of domestic pigs. During winter, 96 pigs were tested in a 2 x 4 factorial experiment involving fungal-residue media from production of Flammulina velutipes or Pleurotus eryngii, each added at rates of 0%, 15%, 45% or 60% of bedding that otherwise consisted of sawdust, rice husks, corn flour and Bacillus subtilis. After 98 days, growth factors and biomarkers of stress were analysed, and the condition of the bedding materials was examined. Fungal residues from either source, as 45% of bedding material, were associated with higher growth performance, lower stress, less huddling and higher immunity of pigs. Beddings with 45% fungal-media residues were also warmer, with lower levels of odorous chemicals, and higher numbers of beneficial microbes. No significant difference was observed between the two residue sources. Higher (60%) or lower (15%) concentrations of residue in beddings caused minor or insignificant improvements. In summary, bedding consisting of 45% fungal-residue media can improve the growth performance and welfare of domestic pigs during winter and is safe to promote.