This study aimed to assess the environmental footprint of dairy farms rearing a dual-purpose breed, and to evaluate, through alternative scenario analyses, the fattening of calves and the cultivation of hemp as strategies for reducing the environmental impact of these farms. Eleven farms were evaluated for global warming (GWP), acidification (AC) and eutrophication (EUP) potential. The Life Cycle Assessment method with three scenarios, REAL, based on real data, BEEF, where calves were fattened in farm, and HEMP, where hemp was cultivated in farms, were considered. If referred to 1 m2 of utilizable agricultural land, the GWP, AC and EUP were 1.6 kgCO2eq, 21.7 gSO2eq and 7.1 gPO43-eq, respectively. If referring to 1 kg of fat and protein corrected milk, the emissions were 1.1-1.4 kgCO2eq, 14.8-19.0 gSO2eq, and 5.0-6.4 gPO43-eq, depending on the allocation method adopted. The emissions were associated positively with culling rate and negatively with production intensity. In BEEF and HEMP scenarios, the emissions were reduced by 8-11% and by 1-5%, respectively. Fattening the calves, evaluating the cultivation of alternative plants and improving the productive and reproductive efficiency of animals could be effective strategies for reducing the environmental footprint of the farm.
Keywords: LCA; acidification; cattle; climate change; eutrophication.