A critical review of advancement in scientific research on food animal welfare-related air pollution

Unraveling the potential of hydrogen sulfide as a signaling molecule for plant development and environmental stress responses: A state-of-the-art review

Over the past decade, a plethora of research has illuminated the multifaceted roles of hydrogen sulfide (H2S) in plant physiology. This gaseous molecule, endowed with signaling properties, plays a pivotal role in mitigating metal-induced oxidative stress and strengthening the plant's ability to withstand harsh environmental conditions. It fulfils several functions in regulating plant development while ameliorating the adverse impacts of environmental stressors. The intricate connections among nitric oxide (NO), hydrogen peroxide (H2O2), and hydrogen sulfide in plant signaling, along with their involvement in direct chemical processes, are contributory in facilitating post-translational modifications (PTMs) of proteins that target cysteine residues. Therefore, the present review offers a comprehensive overview of sulfur metabolic pathways regulated by hydrogen sulfide, alongside the advancements in understanding its biological activities in plant growth and development. Specifically, it centres on the physiological roles of H2S in responding to environmental stressors to explore the crucial significance of different exogenously administered hydrogen sulfide donors in mitigating the toxicity associated with heavy metals (HMs). These donors are of utmost importance in facilitating the plant development, stabilization of physiological and biochemical processes, and augmentation of anti-oxidative metabolic pathways. Furthermore, the review delves into the interaction between different growth regulators and endogenous hydrogen sulfide and their contributions to mitigating metal-induced phytotoxicity.

Multivariate analysis for data mining to characterize poultry house environment in winter

The processing and analysis of massive high-dimensional datasets are important issues in precision livestock farming (PLF). This study explored the use of multivariate analysis tools to analyze environmental data from multiple sensors located throughout a broiler house. An experiment was conducted to collect a comprehensive set of environmental data including particulate matter (TSP, PM10, and PM2.5), ammonia, carbon dioxide, air temperature, relative humidity, and in-cage and aisle wind speeds from 60 locations in a typical commercial broiler house. The dataset was divided into 3 growth phases (wk 1-3, 4-6, and 7-9). Spearman's correlation analysis and principal component analysis (PCA) were used to investigate the latent associations between environmental variables resulting in the identification of variables that played important roles in indoor air quality. Three cluster analysis methods; k-means, k-medoids, and fuzzy c-means cluster analysis (FCM), were used to group the measured parameters based on their environmental impact in the broiler house. In general, the Spearman and PCA results showed that the in-cage wind speed, aisle wind speed, and relative humidity played critical roles in indoor air quality distribution during broiler rearing. All 3 clustering methods were found to be suitable for grouping data, with FCM outperforming the other 2. Using data clustering, the broiler house spaces were divided into 3, 2, and 2 subspaces (clusters) for wk 1 to 3, 4 to 6, and 7 to 9, respectively. The subspace in the center of the house had a poorer air quality than other subspaces.

Comparative effects of dietary herbal mixture or guanidinoacetic acid supplementation on growth performance, cecal microbiota, blood profile, excreta gas emission, and meat quality in Hanhyup-3-ho chicken

Phytogenic feed additives are renowned for their growth promotion, gut health enhancement, and disease prevention properties, which is important factors for sustaining prolonged poultry rearing. The study aimed to evaluate the effect of herbal mixture (mixture of ginseng and artichoke) or guanidinoacetic acid (GAA) on growth performance, cecal microbiota, excretal gas emission, blood profile, and meat quality in Hanhyup-3-ho chicken. A total of 360 one-day-old chickens (half males and half females) were allocated into one of 3 dietary treatments (12 replicate cages/treatment; 10 broilers/replicate cage) for 100 d of age. Experimental diets were CON: basal diet; TRT1: basal diet combined with 0.05% herbal mixture; and TRT2: basal diet combined with 0.06% GAA. All birds received a basal diet during the first 30 d, but from d 31 to 100, an experimental diet was supplied. The addition of 0.05% herbal mixture improved the average body weight gain and feed conversion ratio from d 31 to 100 as well as the overall experimental period. The cecal Lactobacillus, Escherichia coli, and Salmonella count remained consistent across all dietary treatments. Blood albumin and Superoxide Dismutase (SOD) levels increased in the herbal mixture supplemented diet. Additionally, there was a notable reduction in excretal NH3 and H2S emissions in the herbal mixture group. Furthermore, the herbal mixture group exhibited increased breast muscle weight, improved breast muscle color, improved water holding capacity, and a decrease in abdominal fat compared to the control group. Additionally, the supplementation of 0.06% GAA did not demonstrate any statistically significant impact on any evaluated parameter throughout the experiment. The results from the present investigation underscore the potential of ginseng together with artichoke extract supplementation as a viable feed additive, conferring improvements in growth performance, feed efficiency, excreta gas emission, meat quality parameters, and defense mechanism against oxidative stress in Hanhyup-3-ho chicken.

Maternal exposure to particulate matter from duck houses restricts fetal growth due to inflammatory damage and oxidative stress

The composition of particulate matter (PM) in poultry farms differs significantly from that of atmospheric PM as there is a higher concentration of microbes on farms. To assess the health effects of PM from poultry farms on pregnant animals, we collected PM from duck houses using a particulate sampler, processed it via centrifugation and vacuum concentration, and subsequently exposed the mice to airborne PM at 0.48 mg/m3 (i.e., low concentration group) and 1.92 mg/m3 (i.e., high concentration group) on the fifth day of pregnancy. After exposure until the twentieth day of pregnancy or spontaneous delivery, mice were euthanized for sampling. The effects of PM from duck houses on the pregnancy toxicity of mice were analyzed using histopathological analysis, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction (qPCR). The results showed that exposure to PM had adverse effects on pregnant mice that reduced their feed intake in both groups. Microscopic lesions were observed in the lungs and placentas of pregnant mice, and the lesions worsened with increased PM concentrations, as shown by alveolar wall thickening, the infiltration of inflammatory cells in pulmonary interstitium, congestion, edema, and cellular degeneration of placenta. In pregnant mice in the high concentration group, exposure to PM significantly increased the expression of inflammatory cytokines in the lungs and placentas, caused oxidative stress, and decreased estrogen level in the blood. Exposure to PM also resulted in the reduced litter sizes of pregnant mice and shorter body and tail lengths in the fetuses delivered. Beyond that, exposure to PM significantly downregulated the levels of antioxidant factor superoxide dismutase and neurotrophic factor Ngf in the brains of fetuses. Collectively, exposure to a high concentration of PM by inhalation among pregnant mice caused significant pregnancy toxicity that led to abnormal fetal development due to inflammatory damage and oxidative stress. These findings established a foundation for future studies on the underlying mechanisms of pregnancy toxicity induced by exposure to PM.

Development of a H2S-responsive NIR Fluorescent Probe for H2S Detection and H2S Releasing Monitoring From Prodrug

H2S was deemed as a toxic gradient in the realm of food and environment but plays pivotal pathophysiological roles in organisms. H2S instabilities and disturbances are always responsible for multiple disorders. We fabricated a H2S-responsive NIR fluorescent probe (HT) for H2S detection and evaluation both in vitro and in vivo. HT exhibited rapid H2S response within 5 min, accompanied with visible color change and NIR fluorescence generation, and the fluorescent intensities were linearly correlated with corresponding H2S concentrations. When HT was incubated with A549 cells, the intracellular H2S and H2S fluctuations could be monitored ore rotundo via the responsive fluorescence. Meanwhile, when HT was co-administrated with H2S prodrug ADT-OH, the H2S release from ADT-OH could be visualized and monitored to evaluate its release efficacy.

Air Quality Assessment in Pig Farming: The Italian Classyfarm

On 24 September 2019, the Ministry of Health issued an explanatory circular containing clarifications on the implementation methods of the National Improvement Plan for the application of Legislative Decree 122/2011. The Plan states that "In all farms where weaning or fattening pigs are raised and in breeding farms which wean piglets (excluding those for self-consumption), a risk assessment is carried out by the veterinarian on the basis of three levels: insufficient, room for improvement and optimal". ClassyFarm, a risk assessment tool for livestock farming, is applied in Italy to evaluate the level of welfare and management of animals from a variety of points of view. Essentially, the categorization risk introduced by ClassyFarm in pig farming depended on the obligation stated by the EU in Decree 122/2011 to avoid tail docking in piglets and, at the same time, to reduce the stressor aspects able to induce aggressive behavior among pigs, improving the welfare and health status of animals. Since ClassyFarm evaluates many aspects of the management of animal farming, our aims in this review are to discuss the topic from an environmental point of view: (1) to frame the indications of ClassyFarm to make a farm risk assessment based on pigs' welfare; (2) to review environmental quality assessment in pig farms, and its repercussions on animal health and welfare; (3) to describe the most used sampling techniques of air pollutants measurements.

Overview of Avian Sex Reversal

Sex determination and differentiation are processes by which a bipotential gonad adopts either a testicular or ovarian cell fate, and secondary sexual characteristics adopt either male or female developmental patterns. In birds, although genetic factors control the sex determination program, sex differentiation is sensitive to hormones, which can induce sex reversal when disturbed. Although these sex-reversed birds can form phenotypes opposite to their genotypes, none can experience complete sex reversal or produce offspring under natural conditions. Promising evidence indicates that the incomplete sex reversal is associated with cell autonomous sex identity (CASI) of avian cells, which is controlled by genetic factors. However, studies cannot clearly describe the regulatory mechanism of avian CASI and sex development at present, and these factors require further exploration. In spite of this, the abundant findings of avian sex research have provided theoretical bases for the progress of gender control technologies, which are being improved through interdisciplinary co-operation and will ultimately be employed in poultry production. In this review, we provide an overview of avian sex determination and differentiation and comprehensively summarize the research progress on sex reversal in birds, especially chickens. Importantly, we describe key issues faced by applying gender control systems in poultry production and chronologically summarize the development of avian sex control methods. In conclusion, this review provides unique perspectives for avian sex studies and helps scientists develop more advanced systems for sex regulation in birds.

CuO-decorated MOF derived ZnO polyhedral nanostructures for exceptional H2S gas detection

Considering that H₂S is a hazardous gas that poses a significant risk to people's lives, research into H₂S gas sensors has garnered a lot of interest. This work reports a CuO/ZnO multifaceted nanostructures(NS) created by heat treating Cu²⁺/ZIF-8 impregnation precursors, and their microstructure and gas sensing characteristics were examined using various characterization techniques (XRD, XPS, SEM, TEM, and BET). The as-prepared hollow CuO/ZnO multifunctional nanostructures had a high gas response value (425@50 ppm H₂S gas), quick response and recovery times (57/191s @20 ppm), a low limit of detection (1.6@500 ppb H₂S), good humidity resistance and highly selective towards H₂S gas. The hollow CuO/ZnO multifaceted nanostructures possessed enhanced gas sensing capabilities which may be related to their porous hollow nanostructures, the manufactured p-CuO/n-ZnO heterojunctions, and the spillover effect between CuO and H₂S.

Effect of multi-strain probiotics on the performance of AA+ male broilers

The aim of the experiment was to investigate the effects of a probiotic complex (PC) consisting of Bacillus subtilis, Clostridium butyricum and Enterococcus faecalis on productive performance, carcass traits, immune organ indices, fecal microbiota counts and noxious gas emissions in AA+ male broilers. Three hundred and sixty 1-day-old AA+ male broilers with similar body weight (44.77 ± 0.25) were randomly divided into 3 treatment groups of 6 replicates each, with 20 broilers in each replicate. The experimental groups consisted of a group fed a basal diet and groups fed basal diet supplemented with 0.1 and 0.2% PC. The results showed that the addition of PC had no significant effect (P > 0.05) on growth performance, and carcass traits of AA+ broilers during the experimental period (1-42 days of age). Dietary addition of PC significantly increased the thymus index of AA+ broilers (P < 0.05), reduced the number of E. coli and Salmonella in feces (P < 0.01) and reduced the concentrations of fecal NH₃ and H₂S emissions (P < 0.01). Furthermore, birds fed 0.2% PC diet had the highest number of fecal Lactobacillus counts. Results indicate that probiotic complex consisting of Bacillus subtilis, Clostridium butyricum and Enterococcus faecalis enhances immune organ development, reduces the number of E. coli and Salmonella in feces, increases the number of Lactobacillus and reduces NH₃ and H₂S emissions in feces. This trial provides a theoretical basis for the use of probiotic complexes in broiler production.

Elemental composition of the hair and milk of black-spotted cows and its relationship with intestinal microbiome reorganization

Background and Aim

The cattle breeding system is facing severe problems associated with the increased negative impact of various human activity areas on the environment and the bodies of farm animals. The use of heavy metals in different production areas leads to their accumulation in the environment due to the ingestion of animals and humans through animal products. This study aimed to assess the elemental composition of the hair and milk of black-spotted cows and to identify the relationship between the content of toxic and essential elements and the state of the intestinal microbiome.

Materials and Methods

The element status was estimated by studying the chemical composition of the biosubstrates using inductively coupled plasma-mass spectroscopy. Based on the analysis of hair, the elemental composition, and the use of the coefficient of toxic load, two groups of animals were formed: Group I, which included cows with a lower load factor, and Group II, which included cows with a higher load factor.

Results

An increase in the heavy metal concentrations in the hair and milk of animals in Group II was observed. The As, Fe, Pb, Al, Co, Ni, and V concentrations in the hair of cows from Group II increased relative to Group I by 19%, 29%, 24.5%, 32.3%, 35.6%, 21.5%, and 18.2%, respectively. There was a significant increase in the level of Fe by 11.5%, Cr by 8.25%, Mn by 17.6%, Pb by 46.1%, and Cd by 25% in Group II compared with Group I in the assessment of elemental milk composition. There were no apparent changes in the intestinal microbiome of Group II.

Conclusion

Some heavy metals were accumulated in the bodies and milk of animals. This shows a high probability of heavy metals causing harm to the health of animals and humans.

Mitigation of Air Pollutants by UV-A Photocatalysis in Livestock and Poultry Farming: A Mini-Review

Ultraviolet (UV)-based photocatalysis has been the subject of numerous investigations focused on mitigating undesirable pollutants in the gas phase. Few works report on applications beyond the proof of the concept. Even less is known about the current state of the art of UV photocatalysis in the context of animal agriculture. A growing body of research published over the last 15 years has advanced the knowledge and feasibility of UV-A photocatalysis for swine and poultry farm applications. This review paper summarizes UV-A photocatalysis technology’s effectiveness in mitigating targeted air pollutants in livestock and poultry farms. Specifically, air pollutants include odor, odorous VOCs, NH3, H2S and greenhouse gases (CO2, CH4, N2O). We trace the progression of UV-A photocatalysis applications in animal farming since the mid-2000 and developments from laboratory to farm-scale trials. In addition, this review paper discusses the practical limitations and outlines the research needs for increasing the technology readiness and practical UV application in animal farming.

Effect of inlet-outlet configurations on the cross-transmission of airborne bacteria between animal production buildings

Cross-transmission of airborne pathogens between buildings facilitates the spread of both human and animal diseases. Rational spatial arrangement of buildings and air inlet-outlet design are well-established preventive measures, but the effectiveness of current configurations for mitigating pathogens cross-transmission is still under assessment. An intensive field study in a laying hen farm was conducted to elucidate the spatial distribution of airborne bacteria (AB) and the source of AB at the inlets under different wind regimes. We found higher concentrations of AB at the interspace and sidewall inlets of buildings with sidewall exhaust systems than at those with endwall exhaust systems. We observed significant differences in bacterial diversity and richness at the interspace and sidewall inlets between buildings with side exhaust systems and those with endwall exhaust systems. We further found that the AB emitted from buildings could translocate to the sidewall inlets of adjacent building to a greater extent between buildings with sidewall exhaust systems than between those with endwall exhaust systems. Our findings revealed that sidewall exhaust systems aggravate cross-transmission of AB between buildings, suggesting that endwall exhaust systems or other compensatory preventive measures combined with sidewall exhaust systems could be a better choice to suppress airborne cross-transmission.

Regulating of LncRNA2264/miR-20b-5p/IL17RD axis on hydrogen sulfide exposure-induced inflammation in broiler thymus by activating MYD88/NF-κB pathway

Hydrogen sulfide (H₂S) is an environmental pollutant. Chronic exposure to H₂S can damage the immune system of birds, but the detailed mechanisms of H₂S-induced thymus toxicity have not been determined. Competitive endogenous RNA (ceRNA) mechanism participates in many pathophysiological processes by regulating gene expression, including environmental pollutant-induced injury. Therefore, we investigate the specific mechanisms of ceRNA in the process of H₂S-induced thymic immune damage in broiler chickens. In the current study, 120 one-day-old male Ross 308 broilers were randomly divided into two groups (n = 60 chickens/group), raising in the control chamber (0.5 ± 0.5 ppm) or H₂S-exposed chamber (4.0 ± 0.5 ppm at 0-3 weeks of age and 20.0 ± 0.5 ppm at 4-6 weeks of age groups) to replicate the H₂S-exposed broilers. NaHS (3 mM or 6 mM) was used to treat chicken macrophages (HD11) to establish an in vitro. Histopathology and ultrastructural changes of thymus were assessed by hematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM). Gene expression profiles were analyzed by using transcriptomics. The underlying mechanisms of thymic injury were further revealed by dual luciferase reporter gene assay, qRT-PCR and Western blotting. Research results showed that H₂S exposure induced an inflammatory response in thymus, with the expression of LncRNA2264 was significantly down-regulated. LncRNA2264 could competitively bind to miR-20b-5p and caused downregulation of the IL17RD. H₂S could activate inflammatory factors through the LncRNA2264/miR-20b-5p/IL17RD axis. In summary, this study suggested that LncRNA2264 acted as a miR-20b-5p molecular sponge to regulate the expression of IL17RD involved in H₂S exposure-induced thymic inflammation, which has positive implications for guiding the prevention and control of H₂S gas poisoning in livestock housing and ensuring animal welfare.

H2S exposure induces cell death in the broiler thymus via the ROS-initiated JNK/MST1/FOXO1 pathway

Hydrogen sulfide (H₂S) is a common toxic gas in chicken houses that endangers the health of poultry. Harbin has a cold climate in winter, and the conflict between heat preservation and ventilation in poultry houses is obvious. In this study, we investigated the H₂S content in chicken houses during winter in Harbin and found that the H₂S concentration exceeded the national standard in individual chicken houses. Then, a model of H₂S exposure was established in an environmental simulation chamber. We also developed a NaHS exposure model of chicken peripheral blood lymphocytes in vitro. Proteomics analysis was used to reveal the toxicology of thymus injury in broilers, the FOXO signaling pathway was determined to be significantly enriched, ROS bursts and JNK/MST1/FOXO1 pathway activation induced by H₂S exposure were detected, and ROS played an important switch role in the JNK/MST1/FOXO1 pathway. In addition, H₂S exposure-induced thymus cell death involved immune dysregulation. Overall, the present study adds data for H₂S contents in chicken houses, provides new findings for the mechanism of H₂S poisoning and reveals a new regulatory pathway in immune injury.