Poultry Manure and Droppings in Law and Natural Sciences: Fertilising Properties, Environmental Risks, and Regulatory Frameworks

The intensification of poultry production in Poland generates enormous quantities of excreta and associated biomass. While these constitute valuable sources of macro- and micronutrients, inadequate waste management leads to environmental pollution, nutrient leaching, and ammonia emissions. This paper analyses the fertilising potential of avian excreta, the legal provisions governing their application, and modern management technologies within the context of the circular economy. The study addresses two global threats—antimicrobial resistance (AMR) and the eutrophication of aquatic ecosystems—evaluating mitigation strategies and advanced biotechnological processing methods. Industrial farming turns excreta into a reservoir of active antibiotics, leading to the contamination of soils, waters, and crops. As a preventative strategy to reduce reliance on veterinary antibiotics—thereby indirectly mitigating the environmental dissemination of AMR—the dietary application of phytobiotics is highlighted. To counteract eutrophication, supplementing feed with exogenous microbial phytase plays a pivotal role, improving phytate phosphorus absorption and reducing its excretion by up to 50%. Furthermore, anaerobic co-digestion with carbon-rich substrates enhances methane yield, while advanced recovery systems (struvite precipitation, electrodialysis, bioelectrochemical concentration, and membrane techniques) show significant potential for safer nutrient concentration. An integrated technological approach to waste processing constitutes the foundation of sustainable agricultural production.