Regarding the hygienic aspects of the production and use of animal wastes, further research on the following aspects is essential: pathogenic agents present in residues of animal production in the context of transmissible multifactorial diseases and the epidemiology of pathogens under different ecological conditions; in animal wastes in the context of the food chain from soil to humans; hygienic effects of animal wastes on water as regards the standards required by medical authorities; effects of agents used to increase animal production, or used for medicinal purposes, which are present as residues in animal excreta and may be hazardous to public health; effects of animal excreta on microbiological processes in the soil; effects of dust and airborne microbial emissions from animal production, and finally, processes of self‑disinfection of manure and livestock slurry during storage as a means of reducing the amounts of chemical disinfectants used, of reducing environmental pollution