Yard trimmings, landscape management and agricultural practices determine the collection of biomass currently destined mainly to the production of a valuable soil amendant by composting. While composting requires energy, especially for the turning/aeration phases and for air treatment (i.e., biofilters in the case of enclosed systems), anaerobic digestion represents an energy positive process that results in production of biogas and digestate, which can be used as fuel and fertilizer, respectively. The focus of the present research was the evaluation of biogas and methane potential of grass collected in two different periods of the year (spring and summer) from riverbanks located in Northern Italy. The conversion to biogas of feedstocks is greatly influenced by the composition of the organic matter, content of cellulose, and lignin in particular. The production of biomass per hectare and the consequent biogas production were also evaluated. The experimental tests were performed on both samples of fresh grass in laboratory scale batch reactors, characterized by 4.0 L of volume and operated in mesophilic conditions (38 °C), for 40 days per cycle. The anaerobic digestion process was performed on a mixture of inoculum and grass, characterized by inoculum:substrate VS (volatile solids) ratio equal to 2. The inoculum was represented by digestate from a full-scale anaerobic digestion plant fed with dairy cow manure. The results in terms of biogas production, biogas quality (CH₄, CO₂, H₂S), and emissions from digestates (NH₃, CO₂ and CH₄) are presented in the paper. Total solids (TS), volatile solids (VS), pH, volatile fatty acids (VFA), alkalinity, acidity vs. alkalinity ratio, fibers (cellulose, lignin), and total Kjieldahl nitrogen (TKN) were determined both on input and output of the process. The biogas yield obtained from grass resulted higher than expected, quite similar to the yield obtained from energy crops, with Biomethane Potential (BMP) of 340.2 NL·kg⁻¹VS and of 307.7 NL·kg⁻¹VS, respectively, for spring and summer grass. Biogas quality was slightly lower for summer grass, perhaps in relation to the higher content of fibers (lignin). Alternatively, the yield of grass per surface was significantly different between spring and summer with the highest production in the summer. In fact, the results revealed a methane yield of 263 Nm³·ha⁻¹ and of 1181 Nm³·ha⁻¹, respectively for spring and summer grass.

During the last decades, many dairy farmers have actively advanced their farms toward automation. Automatic concentrate dispensers and automatic milking systems have been utilised for years, and several manufacturers have introduced automatic feeding systems (AFS). AFSs allow for the increase in frequency of feed distribution with significant advantages in terms of health and production. Furthermore, they provide a reduction of man labour related to preparation of feed, distribution, and propelling the ration closer to the feeding rack. The present research was focused on the monitoring of a dairy farm, located in the Veneto region of Italy, during the transition from a conventional feeding system (CFS), based on a tractor operated mixing wagon, to an automatic system equipped with stationary feeding hoppers, mixing unit, and distribution wagon operating on rail. The article reports a comparative analysis of the structural modifications required for the adoption of AFS, including an analysis of the AFS/CFS systems based on their functionality, energy, and man labour requirements. In the case study, AFS represented an affordable way to reduce covered area of the housings, as a result of the reduction in width of foraging lane and the reduction of manger front length. In addition, AFS demonstrated a reduction in labour requirements and improvement of quality and consistency of work when feeding total mixed ration. Finally, the research was addressed to study dairy cow behaviour. A method for monitoring the feeding, resting, and standing indexes was applied to the CFS farm. As a preliminary result of this activity, a positive correlation between cow resting activity and milk production was discovered.

The aim of this study was to assess the effect of heat stress on dairy cow performance and on the expression of selected genes involved in milk protein metabolism. Eight Italian Holstein Friesian cows were kept under thermoneutral conditions (temperature–humidity index (THI) < 72, CON) for 8 days and under mild heat stress conditions (72 < THI < 78, HS) for an additional 8 days. The rectal temperature, feed intake, and milk yield were recorded during the last 3 days of the CON and HS periods. During the same time period, milk samples were collected to assess the composition and expression of selected genes involved in milk protein metabolism. Gene expression analyses were performed on somatic cells from milk, which are representative of mammary tissue. In terms of dairy cow performance, HS resulted in lower milk and protein yields and feed intake but higher rectal temperature than for CON (p < 0.05). Under HS, there were greater abundances of HSPA1A (p < 0.05) and BCL2 (p < 0.05), compared to CON, but similar levels of CSN2 (p > 0.05), CSN3 (p > 0.05), HSPA8 (p > 0.05), and STAT5B (p > 0.05) mRNA. Mild heat stress reduced the performance of dairy cows without affecting the expression of genes coding for caseins.

Grass from landscape management or from agricultural practices is currently destined mainly for composting, with the production of a valuable product; however, this process demands energy. Anaerobic digestion, instead, represents an energy-positive process that results in the production of fuel, biogas, and a fertilizer, namely digestate. Previous tests for the evaluation of biogas yield from freshly harvested grass gave promising results. However, for a practical exploitation of this resource, appropriate conservation is necessary in order to enable the daily load of digesters while reducing the loss of organic matter. The present work is focused on the evaluation of biogas and methane yield from dried and ensiled grass (without conditioning) in order to assess eventual biogas potential losses in comparison to digested fresh grass. Tests were performed with grass collected from riverbanks (Veneto, Northern Italy) in batch, lab scale digesters. Dry and ensiled grass showed a good potential for exploitation in the anaerobic digestion process, reaching biogas yields of 565.9 and 573.4 NL∙kgVS−1, respectively. Compared to the biogas yield of 639.7 NL∙kgVS−1 of the fresh grass, the conservation treatment determined yield reductions of 11.5% and 10.4% for dried and ensiled grass, respectively. However, considering the methane yields, conservation treatments showed lower reductions, amounting to 4.8% for dry grass and 0.5% for ensiled grass; presumably the higher concentration of organic acids in ensiled grass determined a higher methane content in biogas and the consequently lower reduction of methane yield.

The development of intensive aquaculture is facing the challenge of the sustainable management of effluents. The reproductive sectors (i.e., hatcheries) mainly use water recirculation systems (RAS), which discharge a portion of wastewater. Anaerobic digestion (AD) could reduce the environmental impact of this waste stream while producing biogas. The study is focused on the biochemical methane potential (BMP) of brackish fish hatchery sludges. Wastewater was concentrated by microfiltration and sedimentation and thickened sludges were treated in a BMP system with different inoculum/substrate (I/S) volatile solids ratios (from 50:1 to no inoculum). The highest I/S ratio showed the highest BMP (564.2 NmL CH₄/g VS), while different I/S ratios showed a decreasing trend (319.4 and 127.7 NmL CH₄/g VS, for I/S = 30 and I/S = 3). In absence of inoculum BMP resulted of 62.2 NmL CH₄/g VS. The kinetic analysis (modified Gompertz model) showed a good correlation with the experimental data, but with a long lag-phase duration (from 14.0 to 5.5 days) in particular with the highest I/S. AD applied to brackish water sludges can be a promising treatment with interesting methane productions. For a continuous, full-scale application further investigation on biomass adaptation to salinity and on retention times is needed. Further experimental tests are ongoing.

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.