LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

GROUP 6, SESSION B: METHODS, TOOLS, DATABASES 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
169. Environmental impact and social attributes of small- and largescale
dairy farms
Luciana Bava, Matteo Guerci * , Anna Sandrucci, Alberto Tamburini, Maddalena Zucali
Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Milano, via Celoria 2 , 20133 Milano,
Italy, Corresponding author. E-mail: matteo.guerci@unimi.it
In recent years a growing interest was observed from public opinion in the concept of “sustainability” of
farming systems (Van Calker et al., 2005). A common perception is that a dairy farm based on pasture, with
low-input and low number of cows is more respectful from the environmental point of view than an intensive
and large dairy farm (Capper et al., 2009). The aim of this work is to study the environmental impact and the
social attributes of intensive dairy farms characterised by different scale in terms of number of lactating
cows. We selected 22 dairy farms located in the Po valley in the North of Italy. All the farms were members
of the same cooperative feed industry and belonged to one of the two groups: ≤ 70 or ≥ 150 lactating cows.
The environmental impact of each dairy farm was calculated with a detailed ‘‘cradle-to-farm-gate’’ LCA.
All the processes related to the farm activity (i.e. forage and crop production, energy use, fuel consumption,
manure and livestock management), and all external factors or inputs (i.e. production of fertilisers, pesticides,
feed, energy and fuels, litter materials, replacing animals) were considered as part of the system. The
functional unit chosen was 1 kg fat and protein corrected milk (FPCM, 4.0% of fat and 3.3% of protein content).
LCA was carried out with SimaPro 7.3.2 (PRé Consultants bv., 2011). Gross margin, i.e. revenues
minus direct production costs, excluding labour cost (€/t FPCM) was used as economic indicator. The social
attributes of the farming systems were studied using an on-line questionnaire sent to a large sample of stakeholders
with different age (18 to more than 60). Daily milk production, stocking density and feed selfsufficiency
were not significantly different between the two group of farms; also the production efficiency
and economic performance, expressed as dairy efficiency and gross margin, were similar (Table 1). Large
scale farms had higher percentage of farm land sown with maize for silage, lower percentage of grassland in
comparison with the other group. Nitrogen and phosphorus balances at farm level did not show any significant
difference among farms. Climate change and acidification potentials per kg FPCM showed significantly
lower value in the large scale farms (P < 0.05) compared with smaller ones (Table 2). The results in terms of
climate change potential were in agreement with previous studies of Rotz et al. (2010); this could be due to
the reduction of methane emission determined by the higher intake of maize silage and high moisture maize
silage of cows in large scale farms in comparison with the other group (9.7 vs 7.7 kg DM) (Cedeberg and
Flysiö, 2004). Energy use was higher in small dairy farms compared to large ones. The results of the survey
(n=479) showed that common perception of some aspects of farming systems sustainability is frequently far
from our data, in particular for climate change, eutrophication potential and energy use most of the people
considered that large farm impact more than small ones. The results showed that intensive dairy farms with a
high number of lactating cows fed with maize-based diet reduced the environmental impact of milk production
particularly for greenhouse emission, energy use and land occupation compared with similar intensive
farms but with lower number of cows. The study suggests that ecological sustainability is not compromised
by increasing farm scale.
References
Capper, J.L., Cady, R.A., Bauman, D.E., 2009. The environmental impact of dairy production: 1944 compared
with 2007. J. Anim. Sci. 87, 216-217.
Cederberg C., Flysjö A., 2004. Life cycle inventory of 23 dairy farms in South-Western Sweden. SIK report
no. 728.
Rotz, C.A., Montes, F., Chianese, D.S., 2010. The carbon footprint of dairy production systems through partial
life cycle assessment. J. Dairy Sci. 93, 1266-1282.
Van Calker K.J., Beretsen, P.B.M., Giesen, G.W.J., Huirne R.B.M., 2005. Identifying and ranking attributes
that determine sustainability in Dutch dairy farming. Agr. Human Values 22, 53-63.
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