Estimation of carbon footprint in dairy cattle farms of Southern Italy

This thesis focused on the global warming potential of dairy farms, using a sample of 285 farms which are members of 4 milk cooperatives operating in Southern Italy (3A - Sardinia, Granarolo - Puglia and Basilicata, Asso.La.C. - Calabria, Progetto Natura - Sicilia). The first study estimated the carbon footprint (CF) of milk collected from the member farms of the cooperatives and defined the incidence of the main emission sources in respect to total emissions. A weighted mean of 1.35 kg of CO2eq per average kg of fat-and-protein corrected milk (FPCM) collected by the cooperative was obtained (1.66 kg as farm mean). Farms with the highest milk production level per cow (MYL) and high feed efficiency use had the lowest values of CF. The second study compared 8 approaches (different in number and type of predictors) to estimate enteric emissions for the same farms. All approaches were accurate for methane quantification, although more detailed approaches could be more informative for high-MYL farms. The third study analyzed the developed database with a multivariate approach (discriminant analysis). The most limiting factors for good environmental performance were herd profile, nutritional efficiency and diet digestibility, especially in farms with low MYL, and agronomic efficiency and herd management parameters in farms with high MYL. Further investigations on the same data is needed to identify the best strategies for mitigating GHG emissions in the studied cooperatives.