ANALYSIS OF AMMONIA RELEASE AND BEST AVAILABLE PRACTICES TO SUPPORT FARM MANAGEMENT IN THE REDUCTION OF AMMONIA EMISSIONS IN DAIRY HOUSES

The objective of this thesis work was to verify the levels of ammonia concentrations in different functional areas of naturally ventilated dairy houses, through the measurement of the concentrations of ammonia at different heights from the floor of the breeding environment, also in relation to the main inside microclimatic variables and outside climate conditions. The research activities were carried out in barns located in an area of the Province of Ragusa highly suited to livestock breeding, where are located most of the naturally ventilated barns present in Sicily (Italy). In this work, issues of great interest which concern the protection of animal welfare, salubrity within the breeding environment, the operators safety in the workplace and the environmental protection have been dealt with through the outcomes of this research which gave a contribution to the analysis of ammonia concentrations and microclimatic variables in breeding environments of dairy houses. An experimental protocol for measuring ammonia concentration within the breeding environment at different heights from the floor and for the measurement of the main internal microclimate variables and the external climatic ones was proposed. The ammonia emission values related to the cows housed in the Building A ranged between 0.44 and 0.14 kg/h whereas the values related to the HPU were between 0.31 and 0.10 kg/h/HPU. The Heat balance method yielded ammonia emission values ranging between 0.005 and 0.27 kg/h and 0.004 and 0.19 kg/h/HPU. A technique for the ammonia emissions reduction has been tested, by using a processing residue of the coffee industry. This technique could be regarded as feasible in this field since the experiment showed a reduction of approximately 50% of the emissions and the choice of this dried vegetal material is suitable due to its easy availability in the territory. Finally, indications have been obtained to support farmers management choices in order to reduce ammonia emissions into the breeding environment. They are based on emission reduction techniques adapted to the specific case study.