USO DE UN INÓCULO ENDÓGENO PARA ACELERAR LA DEGRADACIÓN DE MATERIA ORGÁNICA EN UNA GRANJA PORCINA POR MEDIO DEL PROCESO DE COMPOSTAJE

Abstract

In Mexico, pork farms generate organic residues which often are not appropriately treated before being discharged to waste waters or are treated by methods that directly or indirectly damage the environment. Thus, the objective of this study was to evaluate the effect of a bacterial inoculum on the degradation of organic residues under composting conditions. Solid residues from the effluent sump in a pig farm were mixed with sawdust to form a degradation matrix, where pig carcasses were composted. This artificial ecosystem was used to promote the growth and eventual isolation of various microbial species, which were then used to produce a bacterial endogenous inoculum that was maintained in a minimum basal medium based on compost extract in a mineral solution. The inoculum was added to three 150-kg degradation matrices. Three reference matrices, prepared from pig carcasses as described above, were added with 0.1 % peptone solution only. After 98 days of composting, microbiological and bromatological analysis, as well as a bioassay, showed that the inoculum accelerated the decomposition of pig carcasses. Furthermore, the time required to decrease the pathogenic microbial load was reduced in inoculated matrices and the germination index of Raphanus sativus seeds improved, while nitrogen content increased continuously.