COLONIZATION AND DEGRADATION OF CATTLE DUNG - ASPECTS OF SAMPLING, FECAL COMPOSITION, AND ARTIFICIALLY FORMED PATS

Many biotic and abiotic factors influence colonization and degradation of cattle dung pats. Thus, studies using the pat as an experimental u nit require precise methodology to prevent misinterpretation of result s. This paper reports trials in which impact of methodological procedu res on dung fauna and dung degradation was investigated. Factors inves tigated were pat position on pasture, sampling techniques, influence o f various diets, and a comparison between naturally voided versus arti ficially formed pats. Parameters used to measure these factors include d quantitative and qualitative monitoring of dung fauna, including Col eoptera, Diptera, bacteria, nematodes, and Lumbricidae, and assays of pH, moisture content, and organic matter content of dung. An influence of pat position on colonization was seen, with Staphylinidae occurrin g more frequently in pats located toward the center of a pasture compa red with pats located close to a road. Coleoptera larvae preferred the northern parts of the pats. Pat composition influenced colonization o f coleoptera. Staphylinidae and Scarabaeidae preferred pats from cattl e fed with grass, but Hydrophilidae preferred pats from cattle fed com silage. More Coleoptera larvae were collected from pats produced by g razing cattle compared with pats from cattle fed hay or corn silage. T here were no significant differences between artificial and natural pa ts as to the total number of coleoptera, Diptera, or bacteria collecte d. However, development of Diptera larvae was accelerated in the artif icial pats. Degradation of pats measured by content of organic substan ce and pat area was similar in artificial and natural pats.