LABORATORY CULTURE OF BENEFICIAL DUNG SCARABS

Cattle dung accumulation presents problems of pasture fouling, nutrien t loss, intestinal parasitosis, and pest fly development. These proble ms have been confronted, with variable success, with the introduction of coprophagous scarabs (Coleoptera: Scarabaeidae). This work reports the results of field collections and laboratory culture of immature an d adult dung scarabs. We compared several treatments of eggs and larva e in search of good methods for rearing scarabs in aseptic conditions. We collected 13 abundant species from northern and central Argentina. We obtained approximate to 4,500 eggs, some of which we sent to quara ntine facilities in the United States, and others which we reared in o ur laboratory with 5 different techniques. Five common and widespread species, Ontherus sulcator (F.), Gromphas lacordairet Brulle, Dichotom ius semiaeneus (Germar), Sulcophanaeus menelas (Castelnau), and Bolbit es onitoides Harold, had the highest oviposition rates and were also t he easiest to rear. Two methods, freeze-dried and gamma sterilized bro od masses and balls, provided the best results (i.e., percentage of be etles completing development). As a rule, the species with short larva l development time and wide distributions were easier to rear.