The intensification process of the livestock sector has been characterized in recent decades by increasing output of product per hectare, increasing stocking rate, including more concentrated feed in the diet, and improving the genetic merit of the breeds. In dairy farming, the effects of intensification on the environmental impact of milk production are not completely clarified. The aim of the current study was to assess the environmental impacts of dairy production by a life cycle approach and to identify relations between farming intensity and environmental performances expressed on milk and land units. A group of 28 dairy farms located in northern Italy was involved in the study; data collected during personal interviews of farmers were analyzed to estimate emissions (global warming potential, acidification, and eutrophication potentials) and nonrenewable source consumption (energy and land use). The environmental impacts of milk production obtained from the life cycle assessment were similar to those of other recent studies and showed high variability among the farms. From a cluster analysis, 3 groups of farms were identified, characterized by different levels of production intensity. Clusters of farms showed similar environmental performances on product basis, despite important differences in terms of intensification level, management, and structural characteristics. Our study pointed out that, from a product perspective, the most environmentally friendly way to produce milk is not clearly identifiable. However, the principal component analysis showed that some characteristics related to farming intensification, such as milk production per cow, dairy efficiency, and stocking density, were negatively related to the impacts per kilogram of product, suggesting a role of these factors in the mitigation strategy of environmental burden of milk production on a global scale. Considering the environmental burden on a local perspective, the impacts per hectare were positively associated with the intensification level.

The study of milk flow curves provides useful information for enhancing milking efficiency and protecting udder health by adapting milking machine and milking procedures to the physiological requirements of the cow. The aim of this experiment was to investigate, using field data, the relationships among traits of the milk flow curves, their sources of variation, and milking performances in terms of milk production, machine-on time, and udder health. A total of 2,486 milk flow curves of the whole udder were collected in 82 Italian Holstein-Friesian dairy herds in the Lombardy region of Italy. Approximately one-third (35.1%) of milk flow curves were classified as bimodal. Most flow characteristics were influenced by lactation number, days in milk, and peak flow but also strongly affected by premilking operations. Proper udder preparation, including forestripping and predipping, resulted in better milking performances compared with poor preparation, with greater milk yield per milking, shorter milking time, and lesser bimodality. Premilking delay time, between the start of teat stimulation and cup attachment, affected milking time significantly: The shortest milking time was obtained for a range of delay time between 1 and 60 s. As the delay time increased, the percentage of bimodality dropped significantly. Increasing the number of clusters per operator led to greater percentages of bimodal curves. The greater somatic cell count of cows with bimodal curves supports the hypothesis of the negative effect of bimodality on udder health and indicates the importance of avoiding its occurrence using proper pre-milking procedures.

Aims: To verify to what degree reducing capacity is a characterizing parameter of a species, and of the strains themselves within a given species, of lactic acid bacteria. Methods and Results: Eighty-eight strains belonging to 10 species of lactic acid bacteria (LAB) isolated from traditional Italian cheeses were studied for their reduction activity: Enterococcus faecalis, Enterococcus faecium, Enterococcus durans, Streptococcus thermophilus, Lactococcus lactis ssp. lactis, Lactobacillus paracasei ssp. paracasei, Lactobacillus plantarum, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus helveticus and Pediococcus pentosaceus. It was observed that the lactococci reached minimum redox potential before the lactobacilli. The reduction rate of Enterococcus spp. and L. lactis ssp. lactis was higher than that of the streptococci and Lactobacillus spp. All the P. pentosaceus strains had poor reduction activity compared with the other species. Conclusions: The evolution of the redox potential in milk over a time span of 24 h has been found to be a parameter that characterizes a species: the different courses corresponding to the species in question are clearly evident, and interesting differences can also be noted within the same species. Significance and Impact of the Study: The reduction aptitude of strains might be used to select and adapt appropriate strains for use as starters for dairy products.

Agriculture and animal husbandry are important contributors to global emissions of greenhouse (GHG) and acidifying gases. Moreover, they contribute to water pollution and to consumption of non-renewable natural resources such as land and energy. The Life Cycle Assessment (LCA) methodology allows evaluation of the environmental impact of a process from the production of inputs to the final product and to assess simultaneously several environmental impact categories among which GHG emissions, acidification, eutrophication, land use and energy use. The main purpose of this study was to evaluate, using the LCA methodology, the environmental impact of milk production in a sample of 41 intensive Italian dairy farms and to identify, among different farming strategies, those associated with the best environmental performances. The functional unit was 1 kg Fat and Protein Corrected Milk (FPCM). Farms showed characteristics of high production intensity: FPCM, expressed as tonnes per hectare, was 30·8±15·1. Total GHG emission per kg FPCM at farm gate was 1·30±0·19 kg CO₂ eq. The main contributors to climate change potential were emissions from barns and manure storage (50·1%) and emissions for production and transportation of purchased feeds (21·2%). Average emission of gases causing acidification to produce 1 kg FPCM was 19·7±3·6 g of SO₂ eq. Eutrophication potential was 9·01±1·78 ${\rm PO}_{\rm 4}^{{\rm 3} -} {\rm eq}.$ per kg FPCM on average. Farms from this study needed on average 5·97±1·32 MJ per kg FPCM from non-renewable energy sources. Energy consumption was mainly due to off-farm activities (58%) associated with purchased factors. Land use was 1·51±0·25 m² per kg FPCM. The farming strategy based on high conversion efficiency at animal level was identified as the most effective to mitigate the environmental impact per kg milk at farm gate, especially in terms of GHG production and non-renewable energy use per kg FPCM.

The aim of the study was to investigate the effects of season, cow cleanliness and milking routine on bacterial and somatic cell counts of bulk tank milk. A total of 22 dairy farms in Lombardy (Italy) were visited three times in a year in different seasons. During each visit, samples of bulk tank milk were taken for bacterial and somatic cell counts; swabs from the teat surface of a group of cows were collected after teat cleaning and before milking. Cow cleanliness was assessed by scoring udder, flanks and legs of all milking cows using a 4-point scale system. Season affected cow cleanliness with a significantly higher percentage of non-clean (NC) cows during Cold compared with Mild season. Standard plate count (SPC), laboratory pasteurization count (LPC), coliform count (CC) and somatic cell count, expressed as linear score (LS), in milk significantly increased in Hot compared with Cold season. Coagulase-positive staphylococci on teat swabs showed higher counts in Cold season in comparison with the other ones. The effect of cow cleanliness was significant for SPC, psychrotrophic bacterial count (PBC), CC and Escherichia coli in bulk tank milk. Somatic cell count showed a relationship with udder hygiene score. Milking operation routine strongly affected bacterial counts and LS of bulk tank milk: farms that accomplished a comprehensive milking scheme including two or more operations among forestripping, pre-dipping and post-dipping had lower teat contamination and lower milk SPC, PBC, LPC, CC and LS than farms that did not carry out any operation.