Effects of oregano and/or rosemary extracts on growth performance, digestive enzyme activities, cecal bacteria, tight junction proteins, and antioxidants-related genes in heat-stressed broiler chickens

The study examined the impact of adding oregano extract and/or rosemary to broiler diets to counteract the growth inhibition caused by heat stress (HS). It also investigated the effects on the activity of digestive enzymes, microbiological composition, and the expression of antioxidant and tight junction-related proteins. Three hundred- and fifty-day-old male broilers, were randomly assigned to 7 treatment groups, with each group comprising 5 replicates, and each replicate containing 10 chicks in a cage. The diets were: 1) a basal diet, 2) a diet supplemented with 50 mg/kg of rosemary, 3) a diet supplemented with 100 mg/kg of rosemary, 4) a diet supplemented with 50 mg/kg of oregano, 5) a diet supplemented with 100 mg/kg of oregano, 6) a combination diet containing 50 mg/kg each of rosemary and oregano, and 7) a combination diet containing 100 mg/kg each of rosemary and oregano. Dietary oregano extract enhanced the growth and feed utilization of heat-stressed birds, especially at a concentration of 50 mg/kg. Moreover, oregano extract improved jejunal protease and amylase activities. The extracts of rosemary and oregano significantly reduced IgG and IgM levels. Dietary 50 mg oregano extract significantly upregulated intestinal integrity-related genes including jejunal CLDNI, ZO-1, ZO-2, and MUC2. Dietary 50 mg oregano extract significantly downregulated hepatic NADPH oxidase 4 (NOX4) and nitric oxide synthase 2 (NOS2) expressions. Our results suggest that incorporating oregano leaf extract into the diet at a concentration of 50 mg/kg improves the growth performance of broilers exposed to heat stress. This improvement could be attributed to enhanced gut health and the modulation of genes associated with oxidative stress and tight junction proteins.

In-house ammonia induced lung impairment and oxidative stress of ducks

Ammonia (NH3) is a toxic gas that in intensive poultry houses, damages the poultry health and induces various diseases. This study investigated the effects of NH3 exposure (0, 15, 30, and 45 ppm) on growth performance, serum biochemical indexes, antioxidative indicators, tracheal and lung impairments in Pekin ducks. A total of 288 one-day-old Pekin male ducks were randomly allocated to 4 groups with 6 replicates and slaughtered after the 21-d test period. Our results showed that 45 ppm NH3 significantly reduced the average daily feed intake (ADFI) of Pekin ducks. Ammonia exposure significantly reduced liver, lung, kidney, and heart indexes, and lowered the relative weight of the ileum. With the increasing of in-house NH3, serum NH3 and uric acid (UA) concentrations of ducks were significantly increased, as well as liver malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPX-Px) contents. High NH3 also induced trachea and lung injury, thereby increasing levels of tumor necrosis factor-α (TNF-α) and interleukin-4 (IL-4) in the lung, and decreasing the mRNA expressions of zonula occludens 1 (ZO-1) and claudin 3 (CLDN3) in the lung. In conclusion, in-house NH3 decrease the growth performance in ducks, induce trachea and lung injuries and meanwhile increase the compensatory antioxidant activity for host protection.

Stress-Related Gene Expression in Liver Tissues from Laying Hens Housed in Conventional Cage and Cage-Free Systems in the Tropics

Global egg production is mainly based on cage systems, which have been associated with negative effects on the welfare of birds. Stress factors in restrictive production systems can lead to changes in gene transcription and protein synthesis, ultimately impacting the quality of poultry products. The liver serves various metabolic functions, such as glycogen storage, and plays a crucial role in animals' adaptation to environmental changes. Consequently, both internal and external conditions can influence liver functions. The aim of this study was to evaluate the gene expression of AGP, CRP, NOX4, SOD1, CAT, GPX1, SREBF1, and FXR in the liver of laying hens under two different production systems. Liver tissues from Hy-Line Brown hens housed in conventional cage and cage-free egg production systems at 60 and 80 weeks of production were used. mRNA transcript levels were determined by qPCR using the relative quantification method and ACTB as the reference gene. AGP, SOD1, and SREBF1 gene expressions were significantly higher in the conventional cage group at the 60 weeks of production. Furthermore, the mRNA levels of transcripts related to oxidative stress and lipid metabolism were higher in the group of laying hens housed in conventional cages compared to those in cage-free systems. These results suggest differential gene expression of genes related to oxidative stress in liver tissues from hens housed in conventional cages compared to cage-free systems. The conditions of the egg production system can impact the gene expression of oxidative stress and lipid synthesis genes, potentially leading to changes in the metabolism and performance of hens, including egg quality.

Oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers

1. Ammonia is one of major air pollutants in intensive poultry houses, where it causes immunosuppression in broilers. Although previous studies have focused on a particular organ, data on multiple organs have not been reported.2. In the following work, broilers were exposed to environmental ammonia (0, 10, 20, and 40 mg/m³ from 1-21 d old; and 0, 15, 30, and 60 mg/m³ from 22-42 d old).3. Ammonia exposure reduced bird spleen index at 42 d and thymus index at 14, 28, 35 and 42 d, meaning that ammonia caused immunosuppression in birds. Moreover, high ammonia exposure down-regulated the expression of toll-like receptor 4 (TLR4) in lung tissue at 21 d, as well as TLR4 in lung and tracheal mucosa at 42 d when analysed using qRT-PCR. It increased SIgA in saliva at 42 d when analysed by ELISA. Ammonia increased interleukin-6 (IL-6), IL-1β, interferon-α (IFN-α), and IFN-γ in serum at 28 d from the ELISA assay, which indicated that all of these factors took part in ammonia-immunosuppression in birds.4. Three antioxidants (CAT, SOD, T-AOC) decreased, and one oxidant MDA increased after ammonia exposure in the liver and blood, which indicated that ammonia caused oxidative stress via the imbalance of antioxidants/oxidants in birds.5. Correlation analysis showed that TLR4 and TLR15 in the tracheal mucosa were significantly positively related to IFN-γ and negatively related to IL-6. TLR2 in the lung was significantly positively related to IL-1β, and TLR2 in bird tracheal mucosa was negatively related to IL-6 in serum.6. The results suggested that oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers.

Effects of the In Ovo Administration of L-ascorbic Acid on the Performance and Incidence of Corneal Erosion in Ross 708 Broilers Subjected to Elevated Levels of Atmospheric Ammonia

Effects of the in ovo injection of various levels of L-ascorbic acid (L-AA) on the performance and corneal erosion incidence in Ross 708 broilers exposed to 50 parts per million (ppm) of atmospheric ammonia (NH3) after hatch were determined. A total of 1440 Ross 708 broiler embryos were randomly assigned to 4 treatments: non-injected (control), 0.85% sterile saline-injected (control), or saline containing 12 or 25 mg of L-AA. At hatch, 12 male chicks were randomly assigned to each of 48 battery cages with 12 replicate cages randomly assigned to each treatment group. All birds were exposed to 50 ppm of NH3 for 35 d and the concentration of NH3 in the battery cage house was recorded every 20 s. Mortality was determined daily, and mean body weight (BW), BW gain (BWG), average daily BW gain (ADG), and feed intake, as well as feed conversion ratio (FCR), were determined weekly. From 0 to 35 d of post-hatch age (doa), six birds from each cage were selected and sampled for eye erosion scoring. Incidences of corneal erosion were significantly higher at 21 and 28 doa in comparison to those at 14 and 35 doa, and at 21 doa, birds in the saline-injected group exhibited a higher incidence of corneal erosion compared to all other treatment groups. The in ovo injection of 12 mg of L-AA increased BWG (p = 0.043) and ADG (p = 0.041), and decreased FCR (p = 0.043) from 0 to 28 doa in comparison to saline-injected controls. In conclusion the in ovo administration of 12 mg of L-AA may have the potential to improve the live performance of broilers chronically exposed to high aerial NH3 concentrations, but further study is needed to determine the physiological and immunological factors that may contribute to this improvement.

High ambient humidity aggravates ammonia-induced respiratory mucosal inflammation by eliciting Th1/Th2 imbalance and NF-κB pathway activation in laying hens

Ammonia (NH3) is an irritant and harmful gas. Its accumulation in the poultry house poses detrimental effects on the respiratory mucosal system of birds. In this process, the relative humidity of the poultry house also plays an important role in potentiating the adverse effects of NH3 on the respiratory status of birds, causing severe physiological consequences. In this study, the combined effects of NH3 and humidity on the respiratory mucosal barrier of laying hens was studied. The gene expression of tight junction proteins, mucin, inflammatory cytokines secreted by Th1/Th2 cells, and proteins related to the Nuclear factor-κB (NF-κB) signaling pathway were detected by qRT-PCR. In addition, the contents of mucin and secretory immunoglobulin A (SIgA) in bronchoalveolar lavage fluid (BALF) were determined. The results showed that treatment with NH3 alone or NH3 and humidity led to morphological changes in the respiratory tract, decreased the gene expressions of tight junction protein, and increased the expression of mucin. Also, the expression of interleukin-4 (IL-4) and IL-10 were increased, whereas, the expression of interferon-γ (IFN-γ) and IL-2 was decreased in laying hens treated with NH3 and humidity. Furthermore, the activation of inhibitor kappa B kinase β (I-KK-β) and the degradation of inhibitor of NF-κB α (I-κB-α) contributed to the activation of the NF-κB pathway, such that the downstream genes, cycooxygenase 2 (COX2) and inducible nitric oxide synthase (iNOS) were significantly increased. In conclusion, NH3 damaged the mucosal barrier and induced an imbalance in the mucosal immunity, leading to respiratory tract inflammation. Thus, the relative humidity of the environment aggravates the adverse effects of NH3 in poultry.

Quantitative Morphometric, Physiological, and Metabolic Characteristics of Chickens and Mallards for Physiologically Based Kinetic Model Development

Physiologically based kinetic (PBK) models are a promising tool for xenobiotic environmental risk assessment that could reduce animal testing by predicting in vivo exposure. PBK models for birds could further our understanding of species-specific sensitivities to xenobiotics, but would require species-specific parameterization. To this end, we summarize multiple major morphometric and physiological characteristics in chickens, particularly laying hens (Gallus gallus) and mallards (Anas platyrhynchos) in a meta-analysis of published data. Where such data did not exist, data are substituted from domesticated ducks (Anas platyrhynchos) and, in their absence, from chickens. The distribution of water between intracellular, extracellular, and plasma is similar in laying hens and mallards. Similarly, the lengths of the components of the small intestine (duodenum, jejunum, and ileum) are similar in chickens and mallards. Moreover, not only are the gastrointestinal absorptive areas similar in mallard and chickens but also they are similar to those in mammals when expressed on a log basis and compared to log body weight. In contrast, the following are much lower in laying hens than mallards: cardiac output (CO), hematocrit (Hct), and blood hemoglobin. There are shifts in ovary weight (increased), oviduct weight (increased), and plasma/serum concentrations of vitellogenin and triglyceride between laying hens and sexually immature females. In contrast, reproductive state does not affect the relative weights of the liver, kidneys, spleen, and gizzard.

Atmospheric Ammonia Causes Histopathological Lesions, Cell Cycle Blockage and Apoptosis of Spleen in Chickens

The experiment was conducted to investigate the effect of atmospheric ammonia (NH3) on histological changes, cell cycle distribution, and apoptosis of spleen in chickens. 240 chickens were randomly allocated to control group (without NH3 challenge) and NH3 group (70±5 ppm NH3). The experiment lasted for eight days. The results showed that NH3 exposure caused the decreased relative weight (P<0.05), dysplasia of lymphatic follicle, up-regulation of G0G1 phase cells, excessive apoptosis, and increase of reactive oxygen spcecies (ROS) activated cells (P<0.05) in the spleen. The mechanisms of cell cycle blockage were closely related to the upregulation of p53, p21 gene (P<0.05), the downregulation of cyclinD1, cdk6 gene (P<0.05), and the decrease of Proliferating Cell Nuclear Antigen (PCNA) protein (P<0.05). The activated apoptosis could resulted from the increased gene and protein expressions of bax and caspase-3 (P<0.05), and the decreased gene and protein expressions of bcl-2 (P<0.05). The results suggested that 70±5 ppm NH3 caused the spleen dysplasia, which were closely related to the cell cycle arrest and mitochondria apoptotic pathway activation.

The efficiency of natural-ecofriendly clay filters on water purification for improving performance and immunity in broiler chickens

Background

Innovative water treatments and purification processes have become a point of interest to provide solutions and meet the basic water requirements and demands. Clay plays a key role in environmental protection from pollutants through ion exchange and/or adsorption.

Aim

The study evaluated the adsorption and antimicrobial efficiency of clay in purifying polluted water, as well as the influence of clay-purified water on performance, immunity, and microbial counts.

Methods

The experimented 280 one-day-old Hubbard broilers were divided into seven groups on a deep litter system. Polluted water (lead nitrate; 500 mg/l, calcium sulfate; 80 mg/l, yeast extract 5%; 5 mg/l, diazinon; 2.5 ml/l, Salmonella Typhimurium; 1.5 × 106 CFU/ml, and Eimeria tenella; 1 × 105 OPG/ml) was filtered using plastic basins of 1 m3 supplied with 60 cm layer of clay. Broiler groups (G1 to G6) were supplied with clay-filtered and G7 with control tape water. A total of 2,182 samples, including 54 water samples, 266 sera, 266 duodenal swabs, 266 breast muscles, 266 fecal samples, and 1,064 organs including liver, spleen, heart, and bursa of Fabricius were collected.

Results

Weight gains, performance indices, water intakes, water/feed intake ratios, live body weights, carcasses weights, edible and immune organs' weights, immunoglobulin G and M, total antioxidant capacity, lactate dehydrogenase, malondialdehyde, and superoxide dismutase revealed highly significant (p < 0.01) increases in all broiler groups supplemented with clay-filtered water compared to the control group. Meanwhile, total protein, alanine aminotransferase, creatinine, glucose, triglycerides, total cholesterol, cortisol hormone, total bacterial and Enterobacteriaceae counts, total Salmonella counts, and E. tenella counts revealed highly significant (p < 0.01) declines in all broiler groups supplemented with clay-filtered water compared to the control group.

Conclusion

Clay filters provided high filtration, adsorption, and antimicrobial efficiency against polluted water, enhanced water quality, and improved performance and immunity in broiler chickens.

Multidimensional Urban Exposure Analysis of Industrial Chemical Risk Scenarios in Mexican Metropolitan Areas

Risk scenarios are caused by the convergence of a hazard with a potentially affected system in a specific place and time. One urban planning goal is to prevent environmental hazards, such as those generated by chemical accidents, from reaching human settlements, as they can cause public health issues. However, in many developing countries, due to their strategic positioning in global value chains, the quick and easy access to labor pools, and competitive production costs, urban sprawls have engulfed industrial areas, exposing residential conurbations to environmental hazards. This case study analyzes the spatial configuration of accidental chemical risk scenarios in three major Mexican metropolitan areas: Mexico City, Guadalajara, and Monterrey. Spatial analyses use an areal locations of hazardous atmosphere (ALOHA) dispersion model to represent the spatial effects of high-risk industrial activities in conurbations and the potentially affected populations vulnerable to chemical hazards. Complementary geostatistical correlation analyses use population data, marginalization indexes, and industrial clustering sectors to identify trends that can lead to comprehensive environmental justice approaches. In addition, the marginalization degree of inhabitants evaluates social inequalities concerning chemical risk scenarios.

Effects of a Partially Perforated Flooring System on Ammonia Emissions in Broiler Housing-Conflict of Objectives between Animal Welfare and Environment?

Simple Summary

Previous studies have shown positive effects of a partially perforated flooring system on animal welfare in broiler housing. Towards the end of the fattening periods, the present study showed a higher ammonia emission rate (NH₃ ER) for a partially perforated flooring system compared with a littered control barn. Nevertheless, the measured NH₃ concentrations were below 20 ppm, except during a mechanical litter treatment in the winter fattening period. Furthermore, the system offers the possibility of applying practical solutions that were not feasible before. By using underfloor air extraction, manure belts, or acidification systems underneath the elevated perforated area, NH₃ concentrations and the resulting NH₃ ER could be reduced. Thus, with some optimization, the partially perforated flooring system could be used to contribute to an increase in animal welfare and environmental protection at the same time.

Abstract

A partially (50%) perforated flooring system showed positive effects on health- and behavior-based welfare indicators without affecting production performance. Ammonia (NH₃) is the most common air pollutant in poultry production, with effects on animal welfare and the environment. The objectives of animal welfare and environmental protection are often incompatible. Therefore, this study addresses the question of how a partially perforated flooring system affects NH₃ emissions. According to German regulations, three fattening periods were carried out with 500 Ross 308 broilers per barn (final stocking density: 39 kg m⁻²). The experimental barn was equipped with an elevated perforated area in the supply section, accessible by perforated ramps. The remaining area in the experimental barn and the control barn were equipped with wood shavings (600 g m⁻²). Besides the different floor types, management was identical. Air temperature (Temp), relative air humidity (RH), NH₃ concentration, and ventilation rate (VR) were measured continuously. Furthermore, dry matter (DM) content, pH, and litter quality were assessed. Towards the end of the fattening periods, the NH₃ emission rate (ER) of the partially perforated flooring system was higher compared with that of the littered control barn (all p < 0.001). This effect is mainly caused by the higher NH₃ concentrations, which are promoted by the lack of compaction underneath the elevated perforated area and the increase in pH value under aerobic conditions. Nevertheless, the partially perforated flooring system offers different approaches for NH₃ reduction that were previously not feasible, potentially contributing equally to animal welfare and environmental protection.

Micro- and Macroenvironmental Conditions and Stability of Terrestrial Models

Environmental variables can have profound effects on the biological responses of research animals and the outcomes of experiments dependent on them. Some of these influences are both predictable and unpredictable in effect, many are challenging to standardize, and all are influenced by the planning and conduct of experiments and the design and operation of the vivarium. Others are not yet known. Within the immediate environment where the research animal resides, in the vivarium and in transit, the most notable of these factors are ambient temperature, relative humidity, gaseous pollutant by-products of animal metabolism and physiology, dust and particulates, barometric pressure, electromagnetic fields, and illumination. Ambient temperatures in the animal housing environment, in particular those experienced by rodents below the thermoneutral zone, may introduce degrees of stress and thermoregulatory compensative responses that may complicate or invalidate study measurements across a broad array of disciplines. Other factors may have more subtle and specific effects. It is incumbent on scientists designing and executing experiments and staff responsible for animal husbandry to be aware of, understand, measure, systematically record, control, and account for the impact of these factors on sensitive animal model systems to ensure the quality and reproducibility of scientific studies.

Prophylactic impact of nano-selenium on performance, carcasses quality, and tissues' selenium concentration using reversed-phase high-performance liquid chromatography during microbial challenge in broiler chickens

Background and Aim:

Nano-selenium (NS) supplementation contributes in improving productivity, performance, and meat quality while reducing public health concern. Influence of NS and inorganic selenium (Se) water additive on performance, carcass quality, immunoglobulin concentration, intestinal microbiota, Se tissue concentrations, and tissue architecture was studied.

Materials and Methods:

Two-hundred and sixty 1-day-old Hubbard chicks were randomly grouped into five groups (5×52) and supplemented with 0.5 and 1.0 mL of NS and inorganic Se (100 mg.L⁻¹). G1, G2, G3, and G4 were challenged with Escherichia coli O157: H7 2.6×10⁸ on the 14^th day. A total of 2250 samples, including 250 sera, 250 intestinal swabs, and 1500 organ and tissue samples as liver, spleen, heart, bursa, intestine, and breast muscles, and 250 eviscerated carcasses were collected.

Results:

The results revealed a highly significant increase (p<0.01) in live body weights, weight gains, performance indices, carcasses, and organs weights, whereas immunoglobulin G and M concentrations in broilers treated with 0.5 and 1.0 mL NS, respectively, synchronized reveal a highly significant decline (p<0.01) in total bacterial and Enterobacteriaceae counts of intestinal swabs and breast muscles, final pH₂₄, and drip loss in broilers treated with 0.5 and 1.0 mL NS, respectively. Meanwhile, water holding capacity revealed no significant differences between all groups. Reversed-phase high-performance liquid chromatography examination revealed the earlier disappearance of NS residues than inorganic Se from the broiler’s liver and muscles. Histopathological photomicrographs of the liver, spleen, bursa of Fabricius, and intestine, as well as, the immunohistochemistry of intestinal sections revealed superior tissue architecture in broilers treated with NS contrary to inorganic Se.

Conclusion:

The study showed significant stimulation actions of NS on performance, immunity, carcass and meat quality, intestinal and muscles’ bacterial load as well as short withdrawal period and nearly normal cellular architecture compared to inorganic Se.

Effects of chronic heat stress and ammonia concentration on blood parameters of laying hens

Less evidence is available currently to reveal whether the immune system and productivity of laying hens change under long periods of ammonia exposure in hot climate. The present study was conducted to determine the effects of chronic exposure to high temperature and ammonia concentrations on health, immune response, and reproductive hormones of commercial laying hens. A total of five hundred and seventy six 20-week-old laying hens (Hy-Line Brown) were used in this study. Birds were housed in cages (4 birds per cage) and received 16-wk treatments in 6 artificial environmental chambers. Hens were allocated to 6 treatments: treatment 1 (T1, 20°C, ≤5 ppm, control group), treatment 2 (T2, 20°C, 20 ppm), treatment 3 (T3, 20°C, 45 ppm), treatment 4 (T4, 35°C, ≤5 ppm), treatment 5 (T5, 35°C, 20 ppm), and treatment 6 (T6, 35°C, 45 ppm). Blood samples were collected at 22, 26, 30, 34, and 38 wk of age and plasma IgG, IgM, IgA, corticosterone (CORT), total antioxidant capacity (T-AOC), luteinizing hormone (LH), estradiol (E2), and follicular stimulating hormone (FSH) were measured. The results of this study showed that high ambient temperature and excessive ammonia increased the concentration of IgG but decreased the concentration of IgA, T-AOC, LH, FSH, and E2 of hens compared with those of the control birds. From the age of 34 wk, significantly increased concentrations of IgG were observed in hens exposed to moderate and high levels of ammonia. CORT level showed marked differences between the treatments only at the age of 26 wk. In addition, LH and E2 of hens demonstrated significant differences among the treatments in the middle and later stages of the experiment, while FSH levels of the control birds were significantly higher than the others at the age of 38 wk. Excessive ammonia in high temperature was a physiological stress factor that had a negative effect, which inhibited immune function and impacted the reproductive hormones.

Environmental contaminant ammonia triggers epithelial-to-mesenchymal transition-mediated jejunal fibrosis with the disassembly of epithelial cell-cell contacts in chicken

Ammonia (NH₃) is an environmental contaminant that is causing increasing problems with human and animal health due to the development of poultry industry. There are limited studies on the effect of NH₃ inhalation toxicity on the intestinal tract of animals, and underlying molecular mechanisms remain unclear. In the present study, we established a chicken model of NH₃ aspiration-induced injury for 42 days and observed histopathological changes of the jejunum. Tandem mass tag-based quantitative proteomic analysis was applied to investigate changes in the protein profile in the jejunum tissue of chickens that were exposed to NH₃. Overall, 48 significantly differentially expressed proteins (DEPs) were identified. GO and KEGG analyses revealed that most DEPs were closely related to epithelial-to-mesenchymal transition (EMT), cell-cell junctions, and fibrosis-related factors. Regarding fibrosis, type I collagen and fibronectin were significantly increased. With respect to EMT, epithelial marker proteins (such as E-cadherin and keratin) were repressed, while mesenchymal marker proteins (such as vimentin) were activated. Loss of epithelial cell-cell junctions (such as tight junctions, adherens junctions and desmosomes) were observed. Additionally, overexpression of transforming growth factor-beta (TGF-β) may play a key role in the EMT process and fibrosis. Taken together, these findings suggested that NH₃ triggered the EMT and disassembly of epithelial cell-cell contacts, resulting in jejunal fibrosis that was mediated by TGF-β in chickens. The results of our study will contribute to provide a technical reference regarding the research methods of intestinal toxicity of NH₃ and have largely regulatory implications for ecological risk assessment of human health.

Ammonia inhalation-induced inflammation and structural impairment in the bursa of fabricius and thymus of broilers through NF-κB signaling pathway

Ammonia (NH₃) is a toxic, environmental pollutant, and irritant gas. Previous studies reported the toxic effects of NH₃ which led to inflammation in various organs of chicken. However, the exact mechanism of NH₃-induced inflammation in chicken lymphoid organs bursa of fabricius (BF) and thymus is still elusive. Thus, this study was designed to investigate NH₃-induced inflammation in chicken BF and thymus. Experimental chickens were divided into low (5.0 mg/m³), middle (10.0-15.0 mg/m³), and high (20.0-45.0 mg/m³) NH₃-treated groups. To investigate NH₃-induced inflammation in chicken's BF and thymus, histological observation, NO content and iNOS activity, inflammatory cytokine contents, and mRNA levels were performed by light microscopy, microplate spectrophotometer, ELISA assay, and qRT-PCR. The finding of the present study showed that NH₃ exposure reduced BF and thymus index, increased nitric oxide (NO) content and inducible nitric oxide synthase (iNOS) activity, inflammatory cytokine contents and mRNA levels of nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (Cox-2), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), IL-10, IL-1β, IL-18, toll-like receptor 2A (TLR-2A), and iNOS. Histopathological examination revealed signs of inflammation including increased nuclear debris and vacuoles in the cortex and medulla of thymus and bursal follicles. Conclusively, our findings displayed that NH₃ exposure affects the normal function of BF and thymus and led inflammation. The data provided a new ground for NH₃-induced toxicity and risk assessment in chicken production.

Regulatory Effect of Anwulignan on the Immune Function Through Its Antioxidation and Anti-Apoptosis in D-Galactose-Induced Aging Mice

BACKGROUND

Aging is a spontaneous and inevitable phenomenon of biology, which can lead to the gradual deterioration of tissues and organs. One of the age-related deterioration processes is immunosenescence, which leads to changes in the function of immune systems, including immune cells and associated cytokines. A proper modulation of immune responses can improve the age-related immunosenescence process and then reach healthy aging. Schisandra sphenanthera, a traditional Chinese medicine, has been used as both a medicine and a nutritional supplement for thousands of years. Anwulignan, a monomer compound of Schisandra sphenanthera lignans, has been reported to possess an immunomodulatory effect. Therefore, this study was designed to further explore whether Anwulignan could also modulate the immune functions in aging model mice and the underlying mechanism.

METHODS

D-galactose (D-gal) is often used as an inducer of immunosenescence in animals. In this study, a mice model was created by subcutaneous D-gal (220 mg kg-1) for successive 42 days. Then, the blood and spleen tissue samples were taken for the analysis and observation of cytokine levels, immunoglobulin levels, leukocyte numbers, and the phagocytic activity of macrophages, as well as the histological changes, the proliferation ability of lymphocytes, and the biochemical parameters in the spleen tissue.

RESULTS

Anwulignan significantly increased the serum levels of IL-2, IL-4, IFN-γ, lgG, lgM, and lgA, decreased the content of TNF-α and IL-6 in the aging mice, and increased the blood leukocyte number, the phagocytic activity, the lymphocyte proliferation, and the spleen index in vitro. Anwulignan also significantly increased the activities of SOD and GSH-Px, decreased the contents of MDA and 8-OHdG in the spleen tissue, up-regulated the expressions of Nrf2, HO-1, and Bcl2, down-regulated the expressions of Keap1, Caspase-3, and Bax in the spleen cells, and reduced the apoptosis of spleen lymphocytes.

CONCLUSION

Anwulignan can restore the immune function that is declined in D-gal-induced aging mice partly related to its antioxidant capacity by activating the Nrf2/ARE pathway and downstream enzymes, as well as its anti-apoptotic effect by regulating Caspase-3 and the ratio of Bcl2 to Bax in the spleen.

Application of transcriptome analysis: Oxidative stress, inflammation and microtubule activity disorder caused by ammonia exposure may be the primary factors of intestinal microvilli deficiency in chicken

Ammonia (NH₃), an inhaled harmful gas, is not only an important volatile in fertilizer production and ranching, but also the main basic component of haze. However, the effect and mechanism of NH₃ on the intestines are still unclear. To investigate the intestinal toxicity of NH₃ inhalation, morphological changes, transcriptome profiles and oxidative stress indicators of jejunum in broiler chicken exposed to NH₃ for 42 days were examined. Results of morphological observation showed that NH₃ exposure caused deficiency of jejunal microvilli and neutrophil infiltration. Transcriptomics sequencing identified 677 differential expressed genes (DEGs) including 358 up-regulated genes and 319 down-regulated genes. Enrichment analysis of obtained DEGs by Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) found that biological functions and pathways affected by NH₃ included antioxidant function, inflammation, microtubule and nutrition transport. Relative genes validation and chemical detection confirmed that NH₃-induced oxidative stress by activating CYPs and inhibiting antioxidant enzymes promoted inflammatory response and decreased microtubule activity, thus destroying the balance of nutritional transporters. Our study perfects the injurious mechanism of NH₃ exposure and provides a new insight and method for environmental risk assessment.

Impact of lighting color and duration on productive performance and Newcastle disease vaccination efficiency in broiler chickens

Background and Aim

Manipulating lighting colors and regimens is considered an effective mean for improving broiler productivity. The influence of red, blue, and white light-emitting diode (LED) was investigated using three different regimens of lighting and darkness; continuous 23 h light (L):1 h dark (D), continuous 18 h L:6 h D, and intermittent 16 h L:8 h D hours on the performance, carcass weight (CW), feed and water intake (WI), serum glucose (GLUCO), triglycerides (TG), and cholesterol (TC), intestinal bacterial load, growth and metabolic hormones, and efficiency of Newcastle disease (ND) vaccine.

Materials and Methods

A total of 252 1-day-old Ross broilers on deep litter were divided into nine groups. The 1^st, 4^th, and 7^th groups were exposed to continuous 23L:1D, the 2^nd, 5^th, and 8^th groups were exposed to continuous 18L:6D, and the 3^rd, 6^th, and 9^th groups were exposed to intermittent 16L:8D (4L:2D, 4 times) lighting regimen using red, blue, and white LED lights, respectively. A total of 1350 samples (225 sera, 225 swabs, and 900 organ samples) were collected.

Results

Blue LED group revealed a highly significant increase (p<0.01) in live body weight, body weight gain, performance index, CW, spleen, heart, and liver weights, and anti-ND antibody titer, as well as a highly significant decline (p<0.01) of feed intake, WI, GLUCO, TG, TC, growth hormone, insulin, tri-iodothyronine (T3), tetra-iodothyronine (T4), total bacterial count (TBC), and total Enterobacteriaceae count compared to red and white LED lights in all tested lighting regimens. Continuous 23L:1D and 18L:6D regimens were significantly (p<0.01) superior to intermittent 16L:8D in their influence on the performance, CW, biochemistry, hormonal profile, and bacterial load.

Conclusion

The blue LED light associated with continuous 18L:6D or 23L:1D h regimen is highly recommended in broiler houses for their enhancing the productive performance, growth, and immunity.

Immunomodulatory influences of sialylated lactuloses in mice

The aim of this study was to investigate the immune modulatory influences of sialylated lactuloses in mice. The effects of the four sialylated lactuloses by gavage methods on the weight gain rate, organ, serum and spleen immunoglobulin of mice were investigated. Neu5Ac-α2,3-lactulose group and Kdn-α2,3-lactulose group had significantly higher weight gain rate than control group. The weight gain rate, thymus index and spleen index of Kdn-α2,3-lactulose group were significantly higher than control group and lactulose group. Liver and small intestine of Neu5Ac-α2,3-lactulose group, Neu5Ac-α2,6-lactulose group and Kdn-α2,6-lactulose group showed different degree of damage. IgG levels of serum and spleen in Neu5Ac-α2,6-lactulose group and Kdn-α2,6-lactulose group were significantly higher than control group and lactulose group. The contents of IgG in serum and spleen of Kdn-α2,3-lactulose group were significantly lower than that of control group, while the contents of IgA and IgM in serum were significantly higher than those of control group. The IgA level increased by 12.23% and 58.77% comparing with lactulose group and control group, respectively. The IgM level in serum of Kdn-α2,3-lactulose group mice increased by 43.88% and 8.05% comparing with control group and lactulose group, respectively. The IgA level and IgM level in spleen of Kdn-α2,3-lactulose group mice increased by 49.05% and 47.25% comparing with control group. In short, Kdn-α2,3-lactulose is relatively safe and superior to use as a food supplement or potential drug candidate. Our results also indicate that some other sialylated oligosaccharides are potentially harmful to organisms, they may cause some side effects.

Ammonia production in poultry houses can affect health of humans, birds, and the environment-techniques for its reduction during poultry production

Due to greater consumption of poultry products and an increase in exports, more poultry houses will be needed. Therefore, it is important to investigate ways that poultry facilities can coexist in close proximity to residential areas without odors and environmental challenges. Ammonia (NH₃) is the greatest concern for environmental pollution from poultry production. When birds consume protein, they produce uric acid, ultimately converted to NH₃ under favorable conditions. Factors that increase production include pH, temperature, moisture content, litter type, bird age, manure age, relative humidity, and ventilation rate (VR). NH₃ concentration and emissions in poultry houses depend on VR; seasons also have effects on NH₃ production. Modern ventilation systems can minimize NH₃ in enclosed production spaces quickly but increase its emissions to the environment. NH₃ adversely affects the ecosystem, environment, and health of birds and people. Less than 10 ppm is the ideal limit for exposure, but up to 25 ppm is also not harmful. NH₃ can be minimized by housing type, aerobic and anaerobic conditions, manure handling practices, litter amendment, and diet manipulation without affecting performance and production. Antibiotics can minimize NH₃, but consumers have concerns about health effects. Administration of probiotics seems to be a useful replacement for antibiotics. More studies have been conducted on broilers, necessitating the need to evaluate the effect of probiotics on NH₃ production in conjunction with laying hen performance and egg quality. This comprehensive review focuses on research from 1950 to 2018.

Prophylactic and immune modulatory influences of Nigella sativa Linn. in broilers exposed to biological challenge

Background and Aim:

Prophylaxis and disease prevention is an essential strategy among biorisk management in poultry farms that stimulate and maintain the birds’ immunity. The aim of this study was to investigate the prophylactic, and immune-stimulant influence of Nigella sativa Linn. in broilers under biological stress.

Materials and Methods:

A total of 250 1-day-old (ross) chicks were divided into 5 groups; four of which were supplemented with 1.4%, 2.8%, 4.2%, and 5.6% N. sativa Linn., respectively. The four supplemented groups were challenged with Escherichia coli O₁₅₇:H₇ 1.5×10⁸ at a 14^th day old. A total of 1050 samples (150 serum, 150 swab, and 750 organ samples) were collected and examined.

Results:

A highly significant increase (p<0.01) in 5.6% N. sativa Linn. supplemented group in performance traits (body weight, weight gain, and performance index), biochemical parameters (proteinogram, liver enzymes, and creatinine), immunoglobulins concentration, and immune organs’ weight. Meanwile, liver showed improvement of histoarchitecture without fibrosis. Heart showed a mild pericarditis with a mild degree of hydropic degeneration. Bursa, thymus, and spleen showed lymphoid hyperplasia.

Conclusion:

A concentration of 5.6% N. sativa Linn. in broiler’s feed can improve the immune response and subsequent resistance of broilers against diseases.