The growth, fecundity and mortality of the epigeic earthworm Eisenia fetida in cattle manure solids and pig manure solids with different moisture contents (70%,75%, 80%, 85%,90%) were studied for 30 weeks in the laboratory. The maximum weight of E. fetida in the pig manure solids, which had a moisture content of 75%, was 1100 mg after 13 weeks with a highest growth rate of 12.8 mg d(-1). The total number of cocoons and hatchlings produced was lower, compared to those in all the other moisture levels. Generally, earthworms grew bigger and faster in pig manure solids than in separated cattle manure solids but the mortality at all moisture levels in pig manure solids was high, ranging from 20% to 100%. The C/N ratio, NH4 and NO3 contents in the cattle manure solids and pig manure solids were variable both at the beginning of the experiment and in the earthworm casts or vermicomposts. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.