Boot Swabs to Evaluate Cleaning and Disinfection Success in Poultry Barns

Due to the relevance of cleaning and disinfection in farm hygiene management, accurate evaluation of the success of such procedures remains a fundamental challenge for producers. This study aimed to use boot swab sampling to quantify the effects of such practices in poultry barns. For this purpose, the counts of both the total and fecal indicator bacteria were detected after the application of a cleaning and disinfection protocol in identical barns that were occupied by turkeys and broilers. Boot swab samples were compared to an established agar contact plating method to evaluate disinfection success. Statistical analyses showed no correlations between the bacterial counts that were obtained with either method. In contrast to the agar contact plating method, boot swab sampling permitted the assessment of the hygienic conditions of the barn floors before and after cleaning procedures. Furthermore, according to observations with the boot swab method, factors related to the species being farmed influenced the initial bacterial loads but did not affect the effectiveness of cleaning and disinfection. Species identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) also suggested that non-fecal bacteria grow on selective media. Further studies should validate the use of this sampling technique by comparing different cleaning and disinfection protocols.

The magnetic stir bar as a source of impurities in laboratory blank solutions of the environmental samples subjected to microwave-assisted acid digestion

Teflon-coated magnetic stir bars are suspected to be a source of impurities for the laboratory blank solutions. To evaluate the ability of magnetic bars to absorb and release different elements at sub-ppb and above-ppb (µg L-1) level the experiment with new and used bars was conducted. The bars were subjected to microwave-assisted acid digestion with the soil sample and a series of successive cleaning procedures. The ICP-OES/MS analysis of the obtained extracts revealed that most of the elements may be released during subsequent extractions in the ppb-level concentrations, whereas the following elements: Cr, Cu, Sb, Sn, and Pb may be extracted even in elevated concentrations. SEM/EDS inspection of Teflon surfaces demonstrated the multiple defects that probably increase the absorption of the elements. We concluded that the concentration of mineral impurities in the laboratory blank solution prepared in the randomly selected one vessel per sample preparation batch is hardly propagated to the other used vessels. The alternative concept "blank per vessel" was proposed especially for ultra-trace analysis. Also, an additional step in the bar washing procedure was proposed.

Valorization of Urban Street Tree Pruning Residues in Biorefineries by Steam Refining: Conversion Into Fibers, Emulsifiers, and Biogas

Street tree pruning residues are a widely available and currently undervalorized bioresource. Their utilization could help alleviate an increasing biomass shortage and offset costs of the pruning process for the municipalities. In this work, a holistic valorization pathway of pruning residues leading to fibers, oligosaccharides, biogas, and compost is presented. For this, representative mixtures of tree pruning materials from the most prevalent street tree genera (oak, linden, maple) found in Hamburg (Germany) were prepared by shredding and cleaning procedures. Collection of sample material was performed in summer and winter to account for seasonality. A steam-based fractionation was conducted using treatment severities ranging from log R0 = 2.5 to 4.0. At the highest severity, a fiber yield of around 66%, and liquor yield of 26–30% was determined. The fibers were evaluated with respect to their properties for paper product applications, with higher treatment severities leading to higher paper strengths. From the oligosaccharide-rich liquor, emulsions were created, which showed promising stability properties over 8 weeks of storage. The liquors and the rejects from the material preparation also displayed good potential for biomethane production. Overall, the differences between material collected in summer and winter were found to be small, indicating the possibility for a year-round utilization of pruning residues. For the presented utilization pathway, high severity treatments were the most promising, featuring a high liquor yield, good biomethane potential, and the highest paper strengths.

Thermal and chemical disinfection of water and biofilms: only a temporary effect in regard to the autochthonous bacteria

Thermal and chemical disinfection of technical water systems not only aim at minimizing the level of undesired microorganisms, but also at preventing excessive biofouling, clogging and interference with diverse technical processes. Typically, treatment has to be repeated in certain time intervals, as the duration of the effect is limited. The transient effect of disinfection was demonstrated in this study applying different treatments to water and biofilms including heat, chlorination, a combination of hydrogen peroxide and peracetic acid and monochloramine. Despite the diverse treatments, the reduction in live bacteria was followed by regrowth in all cases, underlining the universal validity of this phenomenon. The study shows that autochthonous bacteria could reach the concentrations given prior to treatment. The reason is seen in the nutrient concentration that has not changed and that forms the basis for regrowth. Nutrients are released by disinfection from lysed cells or are still fixed in dead biomass that is subsequently scavenged by necrotrophic growth. Treatment cycles therefore only provide a transient reduction of water microbiology if nutrients are not removed. When aiming at greater sustainability of the effect, biocidal treatment has to be equally concerned about nutrient removal by subsequent cleaning procedures as about killing efficiency.

Environmental and Animal-Related Parameters and the Emissions of Ammonia and Methane from an Open-Sided Free-Stall Barn in Hot Mediterranean Climate: A Preliminary Study

Increased knowledge on the factors that affect emissions from open-sided dairy buildings may lead to an improvement of the mitigation strategies. In this study, ammonia (NH3) and methane (CH4) emissions were assessed in an open dairy barn in a hot Mediterranean climate at different managements of the cooling system, as well as the influence of environmental and animal-related parameters on daily emissions. Measurements of gas concentrations and micro-climatic parameters were carried out in a cubicle free-stall dairy barn located in the province of Ragusa (Italy) in two weeks of 2016 characterised by similar climatic conditions in the warm period. Emissions of NH3 and CH4 were estimated through the application of the carbon-dioxide (CO2) mass balance method. Data collected were organised in specific datasets to carry out different statistical analyses on gas emissions depending on selected parameters for the two weeks with a different management of the cooling system. The results showed higher NH3 emissions and lower CH4 emissions in W1 than those in W2. The variability in gas emissions was related to the effect of temperature humidity index (THI) (p < 0.001) and cow behaviour (p < 0.01). The highest emissions were recorded during the cleaning procedures for both NH3 (p < 0.001) and CH4 (p < 0.001), whereas the lowest emissions were recorded during the central hours of the day.

Efficacy of Removing Bacteria and Organic Dirt from Hands—A Study Based on Bioluminescence Measurements for Evaluation of Hand Hygiene When Cooking

The objective of this study was to evaluate the efficacy of dirt removal (bacteria and organic matter) of several hand-cleaning procedures. The results from the hand hygiene experiment indicated that washing hands with warm water and soap for 20 s is the most effective method investigated when hands are either dirty or greasy. Even if not proper washing, rinsing under running water for 5 s is a cleaning procedure that may significantly reduce the probability of cross-contamination, as it removes 90% of the hands’ dirt. Although less effective than water and soap, the usage of antibacterial wipes was significantly more effective than wet wipes, indicating that they are a better choice when water and soap are not available. The results of this study enable us to inform consumers about the effectiveness of hand-cleaning procedures applied in their homes when cooking. Moreover, it can make consumers understand why, during the COVID-19 pandemic, authorities recommended washing hands as a preventive measure of infection and using an anti-bacterial hand gel or wiping hands with an antimicrobial wipe if water and soap are not available.

The impact of periodontal disease and dental cleaning procedures on serum and urine kidney biomarkers in dogs and cats

The objective of this study was to evaluate the benefits and inherent risks of dental cleaning procedures, based on serum and urine biomarkers for kidney function and tissue damage, in dogs and cats. Thirty-one asymptomatic, mostly older dogs (14 neutered male and 17 ovariohysterectomized female dogs of various breeds between 3 and 14 years old) and cats (19 neutered male and 12 ovariohysterectomized female domestic short hair cats between 2 and 16 years old) diagnosed with periodontal disease on physical exam, and recommended by their veterinarian to have dental cleaning under general anesthesia were evaluated in a prospective study. Serum and urine samples were collected from dogs and cats 1 week before, 6 hours after, and again 1 week after the dental cleaning procedure. Samples were analyzed for biomarkers of kidney function [serum creatinine (Cr), symmetric dimethylarginine (SDMA), and blood urea nitrogen (BUN), and urine for specific gravity (USG) and protein:creatinine (UPC) ratio]. A panel of biomarkers for renal tissue damage was also assessed [serum β-aminoisobutyric acid (BAIB), and urine cystatin B and clusterin]. Samples collected one week before dental cleaning procedures showed that increased age and severity of dental disease were linked to abnormal kidney function biomarker values (age: elevated SDMA and Cr concentrations and isosthenuric USG values; disease severity: elevated UPC ratios) as well as elevated urine cystatin B and clusterin concentrations. Directly after the dental cleaning procedure, an increased number of cats with elevated SDMA concentrations was observed (specifically in cats with longer duration of dental procedures). Extended duration of dental procedures (≥60 min) was linked to increased urine cystatin B and clusterin concentrations, whereas shorter duration procedures was linked to decreased urine cystatin B and clusterin. Higher SDMA concentrations persisted in cats one week after the dental cleaning procedures and were linked to elevated UPC ratios one week before cleaning procedures. In conclusion, the results of this study indicate a link between severity of dental disease, renal tissue injury, and impaired renal function. Longer duration dental procedures in cats may carry inherent risks of kidney injury and impaired renal function.

Using Ultraviolet C (UVC) in Operating Rooms: A Hygiene Improvement

Background: Disinfection procedures are an essential aspect of preventing cross contamination, especially in situations where the risk of infection is higher, such as in operating rooms (ORs). Disinfection procedures in ORs at the end of each surgery session are not the same as final cleaning procedures. We assessed the difference in microbial contamination between different levels of disinfection, before T(0) and after T(1) the use of an ultraviolet C device (UVC-D). Methods: A cross-sectional study was conducted between December 2019 and August 2020 in a private clinic. Three sanitation levels (SL1–SL3) were compared for the reduction in colony-forming units (CFU) between T(0) and T(1): (1) no disinfection after surgery (SL1);, (2) after in-between cleaning (SL2), and (3) after terminal cleaning (SL3). UVC-D was used for 6 minutes, 3 minutes per bed side. Overall, 260 Petri dishes were used in 3 ORs, incubated at 36°C, and CFU were counted after 48 hours. Descriptive statistics, Wilcoxon test, and MANOVA for repeated measures were performed to verify the 95% statistical difference between T(0) and T(1), both on the whole sample and combined with the different SLs. Results: The unstratified analysis showed statistically significant differences (Wilcoxon test, p < 0.05) between T(0) and T(1), with means and standard deviations of 11.42 ± SD 41.19 CFU/PD and 5.91 ± SD 30.89, respectively. The Manova test for repeated measures, applied to 54 pairs of measurements, showed no significant difference between SLs in T(0)-T(1) CFU reduction. Overall, the mean percent reduction in CFU was 93.48% (CI95% = 86.97-99.99%). Conclusions: The results showed significant improvements in disinfection under any condition tested with UVC-D. Using the device immediately after surgery (SL1), before standard cleaning procedures, reduced CFUs by 97.3%. In some situations, UVC light was sufficient to reduce CFU to zero, even without chemical and mechanical cleaning. However, we do not recommend this approach; UVC light disinfection should be applied only after sanitization procedures because it does not remove dirt.Funding: UltraViolet Device, IncDisclosures: None