Tool for determination of climate change related to milk production

Purpose To achieve a sustainable supply of animal origin food, farmers need to identify strategies, that promote the best use of available resources and minimize the potential environmental impact. With this regard, a tool for the evaluation of Climate Change related to the production of cow’s milk was developed. The tool enables farmers to have findings quickly, by providing a method that is easily applicable on a field scale, without the need for tabulated data or empirical formula. Methods Statistical analysis was performed using SAS 9.4 software (SAS Institute, 2012). The first step was performed through a principal component analysis (PCA; PROC PRINCOMP) to study the relationships among total environmental impacts per kilogram of fat and protein corrected milk (estimated trough LCA approach) and several quantitative variables related to farm management on 200 dairy farms. Starting from the most significant variables, a general linear model (GLM) procedure was performed to build an equation suitable to estimate Climate Change (CC) for the production of 1 kg of fat and protein corrected milk (FPCM). Results and Discussion The 200 dairy farms involved in the study resulted different for Utilized Agricultural Area (UAA), 68.4±96.7 ha; arable land was 54.8±30.1% of UAA. Average herd size was 150±145 cows with a milk production of 27.3±4.88 kg FPCM/head/day. CC resulted to be 1.44±0.30 kg CO2 eq/kg FPCM. From the statistical analyses the best equation, suitable to estimate CC for the production of 1 kg of FPCM, included the following variables: Herd size (number of lactating and dry cow); Dry matter intake (DMI; kg/head/d); Milk production (kg FPCM/head/d); Feed self-sufficiency (%). DMI was positively related to CC, while herd size, milk production and feed self-sufficiency were negatively related to the dependent variable. Conclusions The development of this tool can influence the management choice at farm and can improve the chance of mitigation of CC of milk production.