Peer-reviewed scientific studies
Here you will find peer-reviewed scientific publications and conference contributions selected by a scientific committee, documenting — using measurable methods — the impact of SOP practices and treatments in livestock farming and agriculture. For each piece of evidence, we report the context, experimental design, KPIs (e.g., NH₃, CH₄, N₂O, odors, SCC) and, when available, the link to the primary source.
Measuring is the highest form of operational sustainability: what is measurable can be improved, and what is verifiable can be replicated.
Dairy and Beef Cattle Sector
Effects of a blend of deactivated yeast, carob’s condensed tannins and bentonite on lactating dairy cows performance and in vitro fermentation testing long and short term effects.
Benedetti L., Bani G., Bani P., Trevisi E. (2026). Italian Journal of Animal Science, 25:1, 274-286.
Study conducted by the team of Professor Erminio Trevisi (Università Cattolica del Sacro Cuore) at the CERZOO research center. The research evaluated the efficacy of SOP® STAR COW (8 g/head/day) in mid-to-late lactation dairy cows exposed to conditions of progressively increasing heat stress.
The results showed patterns consistent with improved ruminal and metabolic balance, with a marked reduction in ruminal lactic acid (5,01 vs 1,11 mmol/L; -77,8%), associated with a tendency toward increased rumination (+3.2%).
Furthermore, the treatment exhibited higher albumin levels (+5.3%), increased blood calcium (+4.5%), and higher milk fat content (+3.4%) during periods of greater heat stress.
The in vitro trial confirmed improved fermentative efficiency, with a reduction in total gas production (-9.1%).
Mitigating Ammonia Emissions from Liquid Manure Using a Commercially Available Additive Under Real-Scale Farm Conditions
Chiodini M.E., Costantini M., Zoli M., Aspesi D., Poggianella L., Bacenetti J., Atmosphere, 2025
An inter-university study conducted in a commercial barn (University of Milan and University of California, Davis) on bovine slurry. Professor Bacenetti’s team studied ammonia emissions from two parallel tanks over 3.5 months and measured a 77% reduction in ammonia during the first month and an 87% reduction by the end of the trial in the tank treated with SOP LAGOON compared to the baseline. The untreated tank (Standard) showed no statistically significant changes.
-
Real-Scale Study on Methane and Carbon Dioxide Emission Reduction from Dairy Liquid Manure with the Commercial Additive SOP LAGOON
Chiodini M.E., Costantini M., Zoli M., Bacenetti J., Aspesi D., Poggianella L., Acutis M., Sustainability, 2023
An inter-university study in a commercial barn (University of Milan and University of California, Davis) on bovine slurry. Professor Bacenetti’s team monitored greenhouse gas emissions from two parallel slurry tanks over 3.5 months and measured reductions of methane (-80%) and CO₂ (-75%) from the storage tank treated with SOP LAGOON compared to the standard tank. Operators also reported a decrease in odors and a reduction in the time required for slurry agitation before spreading.
-
Effect of SOP “STAR COW” on Enteric Gaseous Emissions and Dairy Cattle Performance
Ross E.G., Peterson C.B., Carrazco A.V., Werth S.J., Zhao Y., Pan Y., DePeters E.J., Fadel J.G., Chiodini M.E., Poggianella L., Mitloehner F.M., Sustainability, 2020
A study by the University of California, Davis, on dairy cows treated with SOP STAR COW compared to a control group. Professor Mitloehner’s team monitored the animals’ production and emission parameters for six weeks and found, at the end of the trial, a reduction in enteric methane emissions (-20.5%) and CO₂ (-18.4%) as well as an improvement in milk quality (+6.5% protein), while the control group showed no significant differences compared to the beginning of the trial.
-
Effects of SOP Lagoon Additive on Gaseous Emissions from Stored Liquid Dairy Manure
Peterson C.B., El Mashad H.M., Zhao Y., Pan Y., Mitloehner F.M., Sustainability, 2020
A study by the University of California, Davis, on the liquid fraction of separated bovine manure stored in barrels for 7 days under static conditions. Professor Mitloehner’s team continuously measured greenhouse gas and ammonia emissions and found reductions in greenhouse gases (-45.4% N₂O, -14.7% CO₂, -22.7% CH₄), ammonia (-45.9%), and odors in barrels treated with SOP LAGOON compared to the untreated control.
-
Improving the Sustainability of Dairy Slurry by A Commercial Additive Treatment,
Borgonovo F., Conti C., Lovarelli, Ferrante V., Guarino M., Sustainability, 2019
A study by the University of Milan on fresh bovine manure stored in barrels for 26 days under static conditions. Professor Guarino’s team measured reductions in greenhouse gases (-100% N₂O, -22.9% CO₂, -21.5% CH₄) and ammonia (-100%), as well as an improvement in the LCA (Life Cycle Assessment) of barrels treated with SOP LAGOON compared to untreated ones. The study also highlights that emissions begin to rise again when the use of the product is stopped.
Case Report: Clinical Mastitis Monitoring on a Commercial Arizona Dairy Farm
Luparia P., Rota N., Poggianella M., Cannizzaro C., Smalley S., Bronzo V., NMC Mastitis Research Workers Meeting (Phoenix, AZ, USA), 2016
A study on 3,000 cows in a commercial barn in Arizona, comparing a control group and a group treated with SOP (additive on bedding/environment) monitored over 3 months. In collaboration with the University of Milan and Professor Bronzo, the researchers found a significant reduction in the incidence of clinical mastitis (P<0,01) in fresh, primaparous, and multiparous cows.
Preliminary results of in-field monitoring of a feed additive for rumen functionality on 7 Italian commercial dairy farms
Luparia P., Rota N., Poggianella M., Bronzo V., ESVCN Congress (Toulouse, Francia), 2015
Monitoring of 7 italian farms (1,357 animals in total) for 1 year before and 1 year after the use of the SOP additive for rumen functionality. Researchers, coordinated by Professor Bronzo from the University of Milan, monitored the animals' response to SOP STAR COW, measuring a +4.14% increase milk production and a -13,52% reduction in somatic cell count (SCC).
Investigation of a bio-hygienizing additive for oral use in Dairy Cows: effect on the somatic cell count in milk Luparia P., Poggianella M., Bronzo V., ADSA-AMPA-ASAS Joint Annual Meeting (Phoenix, AZ, USA), 2012
A study on 140 lactating cows in Northern Italy during the critical summer period (April-September), using the bio-hygienizing SOP additive in the total mixed ration (TMR) car. Researchers, coordinated by Professor Bronzo from the University of Milan, measured a significant reduction (P<0,01) and control of somatic cell levels compared to the control group.
SOP treatment of separated manure solids to reduce Klebsiella bacteria counts
Sharkey H.L., Zanierato A., Luparia P., Poggianella M., Moroni P., Schukken Y.H., NMC 50th Annual Meeting (Arlington, VA, USA), 2011
A study conducted with Cornell University by Professor Ynte Schukken's team on separated manure solids, with daily sampling of piles treated with the bio-hygienizing SOP versus a control. The researchers measured an average reduction of over 90% in Klebsiella counts, with peaks of 99,9% on the second day of treatment compared to the control pile.
The annual monitoring of the SCC on a commercial Italian farm treated with SOP
Zanierato A., Casalone M., Luparia P., Bronzo V., Moroni P., NMC 50th Annual Meeting (Arlington, VA, USA), 2011
A inter-university monitoring study (University of Milan and Cornell University) over 8 months, from December to July, of somatic cell counts (SCC) in primiparous cows in a commercial Italian barn, comparing areas treated with the bio-hygienizing SOP and untreated areas. Researchers, coordinated by Professor Moroni, measured a 52,7% reduction in SCC in post-partum primiparous cows in the treated area.
Monitoring the effects of a Bio-hygienization treatment on the growth performance of calves for replacement heifers
Zanierato A., Accorinti I., Luparia P., Bronzo V., Tetone E., Leslie K., XXVI Buiatrics World Congress (Santiago, Cile), 2010
An inter-university study (University of Guelph, University of Milan) on 19 replacement heifers in Ontario (Canada), with SOP treatment int he bedding of calving pens for 120 days. The study showed improved growth performance, with a 14,04% increase in average daily weight gain compared to the control group.
Monitoring of the efficacy of a Bio-hygienization treatment on the reduction of the microbial load in cubicles with mats of an Italian dairy herd
Favretti M., Moroni P., Bronzo V., Cavalli S., Zanierato A., NMC 49th Annual Meeting (Albuquerque, NM, USA), 2010
A multi-institutional study by the Istituto Zooprofilattico Sperimentale delle Venezie, Cornell University and University of Milan on rubber-matted cubicles; microbiological monitoring was performed every 15 days. Researchers, coordinated by Professor Moroni (Cornell University), measured reductions in total bacterial count (-36,9%), Streptococci (-47,5%), and E. Coli (-30,8%) on surfaces treated with the bio-hygienzing SOP.
Efficacy of a Bio-hygienization additive in controlling the yeast-like microalga Prototheca zopfii
Zanierato A., Buzzini P., NMC 47th Annual Meeting (New Orleans, LA, USA), 2008
An in vitro study by the University of Perugia on the effectiveness of SOP in reducing the concentration of Prototheca zopfii in sterile inoculated manure samples. Professor Buzzini measured a significant reduction (P<0,01) in viable algal cell counts. in the pile treated with the bio-hygienizing SOP compared to the control over time.
Monitoring of the efficacy of a Bio-hygienization treatment on the reduction of the microbial load in cubicles of an Italian herd
Bronzo V., Zanierato A., Varano R., Moroni P., NMC 48th Annual Meeting (Charlotte, NC, USA), 2009
An inter-university study (Cornell University, University of Milan) conducted over 360 days on 140 cows in cubicles with separated manure and straw, divided into SOP and control groups. Researchers, coordinated by Professor Moroni (Cornell University), measured a drastic reduction in microbial load in the bedding, including Streptococci (-81,8%), total coliforms (-81,8%) and E. coli (-76,6%).
Efficacy of a Bio-hygienization additive on microbial control in dairy cow bedding
Tacconi G., Pennacchi M., Boni P., Covarelli A., Zanierato A., NMC 46th Annual Meeting (San Antonio, TX, USA), 2007
A two-year study by the University of Perugia on 60 cows in free-stall housing on straw in Umbria. Researchers, coordinated by Professor Tacconi, monitored animal health and microbial load, measuring reductions in total bacterial count (-96,45%), Micrococcaceae (-98,77%), and Enterobacteriaceae (-93,54%) in the bedding, as well as a 35,58% reduction in somatic cell count in milk after the introduction of the bio-hygienizing SOP.
Evaluation of the efficacy of a litter additive in the control of Staphylococcus spp. and coliform levels: preliminary results of a field trial on organic Chianina beef cattle
Casagrande Proietti P., Franceschini R., Pennacchi M., Tacconi G., 4th World Italian Beef Cattle Congress (Gubbio, Italia), 2005
A field study by the University of Perugia on organic Chianina beef cattle. Researchers, coordinated by Professor Tacconi, observed a 36,78% reduction in Straphylococcus spp. and a 49,79% reduction in coliforms in the bedding treated with the bio-hygienizing SOP compared to the control.
Pig Farming Sector
Monitoring of the efficacy of SOP on the reduction of the microbial load in an Italian commercial fattening pig farm
Tacconi G., Covarelli A., Zanierato A., ADSA-CSAS-ASAS Joint Annual Meeting (Montréal, Canada), 2009
A 23-month monitoring study by the University of Perugia in a finishing pig farm, with monthly slurry sampling. Researchers, coordinated by Professor Tacconi, measured a reduction in bacterial load in slurry treated with SOP PIG LAGOON, including total bacterial count (-73,1%), Micrococcaceae (-62,9%), Strepctococcaceae (-66,9%), and Enterobacteriaceae (-67,6%).
Poultry Farming Sector
Evaluation of the efficacy of a bio-hygienization additive in ammonia level control in broiler houses
Tacconi G., Zanierato A., Covarelli A., ADSA-CSAS-ASAS Joint Annual Meeting (San Antonio, TX, USA), 2007
A study by the University of Perugia on broiler houses (8,200-8,600 birds), comparing ammonia levels in 1st and 7th weeks. Researchers, coordinated by Professor Tacconi, measured a 16% reduction in ambient ammonia during the first week and a 63% reduction by the seventh week in the house treated with the bio-hygienizing SOP.
Evaluation of the efficacy of a litter additive in the control of the ammonia level in broiler houses: preliminary results
Tacconi G., Casagrande Proietti P., Arcaro R., Galli R., 42nd SIPA Meeting (Forlì, Italia), 2003
A study by the University of Perugia on two poultry houses (tunnel-ventilated). Researchers, coordinated by Professor Tacconi, measured a reduction in ammonia levels in the bedding treated with the bio-hygienizing SOP of the 62% during the chick phase and 71% during the adult phase compared to the control.
Agriculture Sector
Reducing N Fertilization without Yield Penalties in Maize with a Commercially Available Seed Dressing
Maris S.C., Capra F., Ardenti F., Chiodini M.E., Boselli R., Taskin E., Puglisi E., Bertora C., Poggianella L., Amaducci S., Tabaglio V., Fiorini A., Agronomy, 2021. A inter-university study (Università Cattolica del Sacro Cuore di Piacenza, Univerisity of Milan, University of Turin, University of California Davis) on maize. Researchers, coordinated by Professor Tabaglio, observed that crops treated with biostimulant Resonant maintained yield despite a 30% reduction in chemical nitrogen fertilization, while also reducing N2O emissions by 23% compared to standard practices.
A new phytostimulating treatment for maize seed germination
Zanierato A., Tassi D., Accorinti I., Luparia P., Vieira de Manincor E., Baffi C., 17th IFOAM Organic World Congress (Namyangju City, Corea), 2011
An experimental study by Università Cattolica del Sacro Cuore di Piacenza and the Istituto Sperimentale Tadini on two maize varieties (class 400 and 700), comparing untreated seeds, treated with conventional coating, and seeds treated with the SOP biostimulant. Researchers, coordinated by Professor Baffi, measured and improvement in emergence speed and uniformity (+100% vs. control and higher than chemical coating) 12 days after sowing in plants treated with SOP biostimulant.
Viticulture Sector
Responses on vegetative growth, yield and quality with the application of Resonant® Fortify White fertilizer in Vitis vinifera L. cv. Chardonnay
Meggio F., Chiodini M.E., Broggio M., Poggianella L., Acutis M., Italus Hortus, 2024
An inter-university, commercial-scale study on grapevines (University of Padua, University of Milan, and UC Davis). Researchers, coordinated by Professor Meggio, observed that plants treated with the biostimulant Resonant for Wine showed greater vigor, reduces water stress (-10%), higher yield (+16%), and increased YAN (Yeast Assimilable Nitrogen) levels (+60%), indicating improved nitrogen uptake efficiency compared to standard practices.