Sheep Red Blood Cells Research Articles

Aflatoxin B1-associated oxidative stress along with toxicopathological and immunological alterations is efficiently counteracted by dietary supplementation of distillery yeast sludge in broilers.

Aflatoxin B1 (AFB1) is among the most potent genotoxic and carcinogenic mycotoxins and is a major source of distress for the growing poultry sector. On the other hand, distillery yeast sludge or distillery sludge (DS) is a byproduct of molasses-based industries. It is often treated as a waste despite containing abundant nutrients particularly protein, basic amino acids, and vitamins along with other macro and micronutrients. This study was designed to investigate the oxidative stress and immunological alterations induced by AFB1 and their amelioration by dietary supplementation with DS. For this purpose, 360 newly hatched broiler chicks were randomly divided into twelve groups (30 birds each) and fed different combinations of AFB1 (100, 200, or 600µg/kg) and DS (5 or 10g/kg) for 42days. The parameters under consideration were body weight, feed conversion ratio (FCR), relative organ weights, histopathological examination of different visceral organs, total antioxidant capacity, antibody response to intravenous injection of sheep red blood cells, in situ lymphoproliferative response to phytohemagglutinin-P, and phagocytic potential through a carbon clearance assay system. The results of this study established that DS supplementation ameliorated AFB1-associated oxidative stress and ameliorated toxicopathological and immunological anomalies in groups given AFB1 at 100µg/kg and 200µg/kg; however, little to no relief was observed in birds fed AFB1 at 600µg/kg. The determination of the actual ratio of the AFB1 to the DS for substantiating the ameliorating effects requires further investigation.

Effects of dietary digestible lysine levels in breeding Japanese quails on productive and reproductive performance, egg quality, blood metabolites and immune responses.

The vegetable-based diet alone does not provide the lysine (Lys) needed to maximize poultry productive performance. This experiment aimed to evaluate the effects of dietary digestible Lys (dLys) level on productive and reproductive performance, egg quality, blood metabolites and immune responses in breeding Japanese quails (Coturnix japonica). The experiment was conducted in a completely randomized design with 6 treatments, 5 replicates and 15 (12 females and 3 meals) 10-week-old breeding Japanese quails each. A basal diet was formulated to meet nutritional requirements of breeding quails except dLys. The basal diet was supplemented with graded (+0.82g/kg) levels of l-Lys-HCl, corresponding to dietary dLys levels of 0.690%, 0.755%, 0.820%, 0.885%, 0.950% and 1.015%. The experiment lasted for 12 weeks, which was divided into 3-4-week periods. Significant differences were observed for egg production (EP), egg mass (EM) and feed efficiency (FE) in response to increasing dietary dLys concentration with quadratic trends. The highest traits were observed in the birds fed with a diet containing 0.885% dLys. However, feed intake, egg quality, reproductive performance, blood metabolites and immune responses against sheep red blood cell inoculation were not significantly affected by increasing dietary dLys concentrations. The dLys requirements during 11-14, 15-18, 19-22 and 11-22 (overall) weeks of age for optimal EP, EM and FE, based on the quadratic broken-line regression analysis, were estimated 272, 265, 250 and 266; 293, 285, 264 and 279; and 303, 294, 281 and 293mg/bird/day, respectively. The dLys requirements vary depending on the EP phase and the trait being optimized. The estimated dLys requirement for FE was higher than those for EP and EM. During the peak stage of the first laying cycle, the dietary dLys level of 0.932% and a daily intake of 303mg dLys/bird are sufficient for optimal performance.

Evaluation of Anti-Inflammatory and Immunosuppressant Potential of Isotelekin in Lipopolysaccharide (LPS) Stimulated Macrophage (RAW 264.7) and Sheep Red Blood Cells (SRBC) Sensitized Murine Models.

The present study explored the natural compound Isotelekin isolated from Inula racemose against anti-inflammatory and immunomodulatory potential in LPS-induced RAW264.7 cell lines and immune-elevated SRBC-sensitized animal models. Isotelekin in in vitro studies, inhibited the production of Th-1 cytokines Interleukin-6 (IL-6), Tumour necrosis factor (TNF-α), and Interferon-gamma (INF-γ),and increased Th-2 cytokines Interleukin-10 (IL-10). Whereas it inhibited the nitrites and reactive oxygen species (ROS) production by mitigating the effect of LPS significantly. In vivo immunomodulatory activity in Delayed-type hypersensitivity (DTH) and Hemagglutinating antibody (HA), Isotelekin suppressed the cellular as well as humoral immunity in immune-affected and SRBC-sensitized mice. Isotelekin decreased the phagocytic responses against carbon particles and plaque-forming mainly IgG (Immunoglobulin G) production. Additionally, Isotelekin showed immunosuppressive potential through the evaluation of splenocytes, allograft acceptance, and haematological parameters. Molecular studies, including western blot analysis and immunocytochemistry, revealed that Isotelekin reduced the expression of iNOS (Inducible nitric oxide synthase), COX-2 (Cyclo-Oxygenase 2), and p-IkBα (Phospho I-kappa-B-alpha), and significantly inhibited the nuclear translocation of NF-κB/p65. Based on these results, Isotelekin at 10 µm in in vitro and at 30mgkg-1 in in vivo demonstrated strong anti-inflammatory and immunosuppressive therapeutic potential.

Antioxidant and immunomodulatory activities of ethanol extracts from Syzygium cumini L. Skeels and Pogostemon cablin Benth

Syzygium cumini and Pogostemon cablin are mostly cultivated in tropical climates for culinary and perfumery purposes, yet their potential medicinal properties remain underreported. The aim of this study was to examine the antioxidant and immunomodulatory activities of ethanol extracts from S. cumini (EESC) and P. cablin (EEPC). Reflux extraction was carried out using 96% ethanol on the collected plant specimens to produce EESC and EEPC. Secondary metabolites of each extract were identified using gas chromatography-mass spectrometry (GC-MS). The extracts were measured for total phenol and flavonoid levels and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. The immunomodulatory activity test was carried out in vivo by assessing several parameters, including the phagocytic index via the carbon clearance method, organ indices, antibody titers, and delayed-type hypersensitivity (DTH) response, using sheep red blood cells (SRBC) as antigens. The extracts were also examined for their anti-inflammatory activity in acute and chronic inflammation models. In the DPPH antioxidant test, EESC and EEPC had IC50 values of 12.33 µg/mL and 182.17 µg/mL, respectively. Both extracts showed immunosuppressant activity, marked by a phagocytic index of <1. EESC yielded lower organ indices for the liver (p=0.025 at 200 mg/kg BW), spleen (p=0.028 at 100 mg/kg BW), and thymus (p=0.032 at 200 mg/kg BW) compared to the control group. For EEPC, lower organ indices were observed in the liver at 100 mg/kg BW (p=0.005) and 200 mg/kg BW (p=0.031). In the primary antibody titer and DTH tests, both EESC and EEPC showed immunosuppressant activity at 200 and 400 mg/kg BW (p<0.05). The extracts suppressed both the innate and adaptive immune systems. Both EEPC (p=0.004) and EESC at 100 mg/kg BW (p=0.03) significantly reduced serum TNF-α levels. In conclusion, EESC and EEPC have the potential as immunosuppressive and anti-inflammatory agents.

Interleukin 9 mediates T follicular helper cell activation to promote antibody responses.

Antigen-specific humoral responses are orchestrated through complex interactions among immune cells in lymphoid tissues, including the collaboration between B cells and T follicular helper (Tfh) cells. Accumulating evidence indicates a crucial role for interleukin-9 (IL-9) in the formation of germinal centers (GCs), enhancing the generation of class-switched high-affinity antibodies. However, the exact function of IL-9 in Tfh cell regulation remains unclear. In this study, we examined the humoral immune responses of CD4Cre/+Il9rafl/fl mice, which lack an IL-9-specific receptor in Tfh cells. Upon intraperitoneal immunization with sheep red blood cells (SRBCs), CD4Cre/+Il9rafl/fl mice displayed diminished levels of SRBC-specific IgG antibodies in their sera, along with reduced levels of GC B cells and plasma cells. Notably, Il9ra-deficient Tfh cells in the spleen exhibited decreased expression of their signature molecules such as B-cell lymphoma 6, C-X-C chemokine receptor 5, IL-4, and IL-21 compared to control mice. In models of allergic asthma induced by house dust mite (HDM) inhalation, CD4Cre/+Il9rafl/fl mice failed to elevate serum levels of HDM-specific IgE and IgG. This was accompanied by reductions in Tfh cells, GC B cells, and plasma cells in mediastinal lymph nodes. Furthermore, group 2 innate lymphoid cells (ILC2s) were identified as producers of IL-9 under immunizing conditions, possibly induced by leukotrienes released by activated IgD+ B cells around the T-B border. These observations may indicate the critical role of IL-9 receptor signaling in the activation of Tfh cells, with ILC2s potentially capable of supplying IL-9 in organized lymphoid tissues.

Variations in the germinal center response revealed by genetically diverse mouse strains.

The humoral response is complex and involves multiple cellular populations and signaling pathways. Bacterial and viral infections, as well as immunization regimens, can trigger this type of response, promoting the formation of microanatomical cellular structures called germinal centers (GCs). GCs formed in secondary lymphoid organs support the differentiation of high-affinity plasma cells and memory B cells. There is growing evidence that the quality of the humoral response is influenced by genetic variants. Using 12 genetically divergent mouse strains, we assessed the impact of genetics on GC cellular traits. At steady state, in the spleen, lymph nodes and Peyer's patches, we quantified GC B cells, plasma cells and follicular helper Tcells. These traits were also quantified in the spleen of mice following immunization with a foreign antigen, namely, sheep red blood cells, in addition to the number and size of GCs. We observed both strain- and organ-specific variations in cell type abundance, as well as for GC number and size. Moreover, we find that some of these traits are highly heritable. Importantly, the results of this study inform on the impact of genetic diversity in shaping the GC response and identify the traits that are the most impacted by genetic background.

The influence of Quercetin on behavior, performance and splenic immunity in broiler chickens

Quercetin (QRT), a potent flavonoid, holds immense mechanistic potential in enhancing various aspects of broiler chicken physiological status. This comprehensive study explores the profound еffеcts of QRT on behavior, productive performance, and immune functions, unraveling the underlying mechanisms behind its efficacy. Four hundred, one-day-old Cobb 500 chicks were placed randomly into 4 supplementation groups (100 birds /group and five replicates) and provided diets enriched with varying concentrations of QRT (0, 200, 400, and 600 ppm) for six weeks. Visual scanning revealed significant (P > 0.05) improvements in feeding and body care behaviors, accompanied by reduced instances of idleness and walking in the QRT-supplemented groups. Moreover, QRT supplementation exerted a substantial (P > 0.05) positive influence on weight gain, feed intake and the final body weight of the broilers. In-depth evaluation of immune parameters, QRT supplementation elicited significant (P > 0.05) enhancements in immune functions, including improved spleen, thymus, and bursa indices, enhanced secretion of immunoglobulin M (IgM) and immunoglobulin A (IgA), and stimulated humoral immunity against sheep red blood cells (SRBCs). Furthermore, QRT displays potent antioxidant properties, as showed by diminished splenic malondialdehyde levels and augmented activity of antioxidative stress enzymes. Remarkably, QRT supplementation elicited dose-dependent upregulation (P < 0.001) of key immune-related genes, such as intеrlеukin-4 (IL-4), interferon-γ (INF-γ), Toll-like receptor 2 (TLR2), and tumor necrosis factor-α (TNF-α) in the splenic tissue. Collectively, these mechanistic insights underscore the profound impact of QRT as a functional feed additive, fostering enhanced behavior, performance, and immune function in broiler chickens, while delivering robust antioxidant fortification.

Investigation of The Effect of Metal-based Medicine Arsenicum album on Humoral Immune Response in SRBC-immunized Mice.

In complementary and alternative medicinal systems, the Arsenicum album in ultra-high dilution was used in various therapeutic conditions, considering its effects on the body's immune system, including the COVID-19 pandemic. However, scientific evidence regarding its immunomodulatory effects is insufficient. The current study aimed to investigate the immunomodulatory effects of Arsenicum album in an experimental mouse model. Immunomodulatory activity of potentized dilutions of Arsenicum album i.e., 6C, 30C, 200C in BALB/c mice was evaluated by humoral antibody titer and delayedtype hypersensitivity assays wherein a fixed concentration (0.5 ml of 1× 109 cells/ml) of freshly prepared sheep RBC was administered as a foreign antigen to generate primary and secondary antibodies. Arsenicum album showed significant immunomodulatory activity by increasing primary antibody titer evaluated on day 21 of the treatment in all the dilutions as compared to SRBC and vehicle control group in humoral immune response assay without showing any effect on delayed-type hypersensitivity. The results of this preliminary study indicate that oral administration of Arsenicum album has the potential to augment primary humoral response at all dilutions. Hence, the possibility of using the Arsenicum album could be explored to treat immunological conditions, infections, etc., as an alternative therapy alongwith modern medicines.

Effect of advanced chelate technology-based trace minerals on growth performance, mineral digestibility, tibia properties, and antioxidant status in two broiler strains

This research aimed to assess the impact of diet supplementation of Advanced Chelate Technology-based Mineral (ACTMS), on the Ross and Arian broilers performance. 520 broilers, of two strains, were allocated to 8 treatments (4 for each strain), 5 replicates, (13 chicks/replicate) and reared for 42 days. The treatments include 0 (CONT), 250 (SBC250), 1000 (SBC1000), and 2000 (SBC2000) of ACTMS. Feed intake, weight gain, and feed conversion ratio were recorded, and the European Production Efficiency Factor (EPEF) was also calculated. Serum antibody was measured in response to sheep red blood cell (SRBC) to evaluate humoral immune response. Blood sample and tibia were used to measure the bone composition of Ca and P. No significant difference was obtained in feed intake (P >0.05), however, weight gain, feed conversion ratio, and EPEF showed significant differences (P˂0.05). The results showed that the interaction effect of Ross× SBC250 had the highest average daily feed intake during 25-42 and 0-42 days of age, but Ross×CONT group provided the lowest average daily feed intake (P˂0.05). Furthermore, the Ross×CONT group had the highest average daily gain during 0-10, 25-42, and 0-42 days of age (P<0.05). The Ross×CONT group also provided the best feed conversion ratio during 0-10 days of rearing period compared to other treatments (P<0.05). Various levels of ACTMS, significantly (P˂0.05) enhanced the antioxidant activity of superoxide dismutase and glutathione peroxidase. No significant differences were obtained in blood parameter (P>0.05), though, SBC2000 exhibited the greatest numerical phosphorus content. There was no significant impact of strain effects on blood metabolites, however, the Ross strain exhibited higher values. The results indicated that the Arian× SBC250 group had the largest tibia diameter which had a significant difference from the Arian×CONT group (P<0.05). In conclusion, ACTMS inclusion in the ration (either replacement or on top) led to the significant improvement of FCR and ADWG (SBC250 as on top) and EPEF (SBC2000 replacement) in the Ross strain and some parameters in Arian strains (mostly numerically).

Humoral Immunity in chicken lines developed by Embrapa Suínos e Aves: Natural and specific antibodies

The antibodies produced in the first days of vertebrate life and are called natural antibodies (NAb). Other antibodies, produced in response to restricted contact with the antigen, are called specific antibodies (SpAb). To evaluate the production of NAb studies have used rabbit red blood cells (RRBC). On the other hand, evaluation of the production of specific antibodies can be performed with the use of sheep red blood cells (SRBC), a cell type that results in high production of SpAb. The aim of this study was to evaluate the production of NAb and SpAb in chicken lines developed by EMBRAPA Suínos e Aves. Animals of laying and poultry lines were inoculated intramuscularly with 5% of SRBC. The titers of NAb and SpAb were higher in laying hens than in broiler lines. The same results were obtained with anti-RRBC, the exception was males of the LLc lines, with lower antibody production compared to the other lines and females of the same line. These data show that the production of natural and specific antibodies is higher in laying hens compared to broilers, and that there is an effect of sex on antibody production.

Synthesis of amino juglone derivatives with adjuvant activity against clinical isolated methicillin-resistant staphylococcus aureus strains

1,4-naphthoquinones hydroxyderivatives belong to an important class of natural products and have been known as a favored scaffold in medicinal chemistry due to their multiple biological properties. Juglone is one of the most important 1,4-naphthoquinone extracted from juglandaceae family showing a good antibacterial activity. In this study, we report the synthesis of aminojuglone derivatives through Michael addition reaction using Cerium (III) chloride heptahydrate (CeCl3·7H2O) as catalyst. The synthesized aminojuglone derivatives were evaluated for their antibacterial properties against sensitive, clinical resistant Gram-positive and Gram-negative bacterial strains. Compound 3c showed a good antibacterial activity similar to cloxacillin (2 µg/mL) against the clinically resistant S.aureus. The antibiotic adjuvant activity of compounds was evaluated in combination with three clinically use antibiotics. The combination of compounds 3a, 3b, 3e, 3 h-3 l, 3n and 3o with cloxacillin showed remarkable adjuvant activity against clinically resistant S. aureus (66-fold potentiation of cloxacillin activity). 3e is the only compound consistent with the concept of antibiotic adjuvant, presenting insufficient antibacterial activity (MIC > 128 µg/mL) and potentiate the activity of cloxacillin (66-fold) with synergistic effect. A structural characterization of 3e was carried out for the first time using X-ray diffraction technic. Moreover, compound 3e did not show a cytotoxic activity on sheep red blood cells.

Selection for high and low antibody responses to sheep red blood cells influences cytokine and chemokine expression in chicken peripheral blood leukocytes and splenic tissue

White Leghorn chickens from a common founder population have been divergently selected for high (HAS) or low (LAS) antibody responses to sheep red blood cells (SRBC) for 49 generations resulting in 2 diverse lines for this trait. Much has been studied in these two lines; however, the impact of these selection pressures on cytokine and chemokine expression is not fully understood. The purpose of this study is to determine if selection for antibody response to SRBC impacts cytokine and chemokine expression in peripheral blood leukocytes (PBL) and spleen from HAS and LAS chickens. Total RNA was isolated from PBL and spleen after which mRNA expression of cytokines (IL4, IL6, IL10, TGF-β4) and chemokines (CXCL8, CCL4) were determined by quantitative real-time RT-PCR (qRT-PCR). The data were analyzed using Student's t test comparing HAS and LAS (P < 0.05) and are reported as corrected 40-CT. PBL and spleen samples were analyzed separately. With respect to PBL, expression of IL6 was higher (P < 0.05) in PBL isolated from LAS chickens compared to those from the HAS line whereas there were no differences (P > 0.05) in IL4, IL10, CXCL8, CCL4, or TGF-β4. The cytokine and chemokine mRNA expression profiles were different in the spleen between the two lines. IL4 and CXCL8 expression were higher (P < 0.05) in spleen samples from HAS chickens than LAS. The expression of IL6, IL10, CCL4, or TGF-β4 in the spleens did not differ (P > 0.05) between the lines. The data indicate that selection for specific antibody responses to SRBC impacts the cytokine and chemokine expression profile in PBL and spleens but in different ways in HAS and LAS. These studies provide insight into the influence that selection pressures for antibody responses have on different immune response components, specifically cytokines and chemokines typically involved in the innate response.

Exploring the effects of varying levels of selenium-chitosan on production performance, egg quality, and immune health in laying japanese quail

The purpose of this research was to see how different levels of Se-chitosan, a novel organic source of Se, affected the production performance, egg quality, egg Se concentration, microbial population, immunological response, antioxidant status, and yolk fatty acid profile of laying Japanese quail. This experiment used a totally randomized design, with 5 treatments, 6 repeats, and 10 birds in each repetition. The dietary treatment groups were as follows: no Se supplementation (control group), 0.2 mg/kg Na-selenite supplementation, and 0.2, 0.4, and 0.6 mg/kg Se-chitosan supplementation. The feed conversion ratio (FCR) improved linearly in quails fed different levels of Se-chitosan compared to the control group (P < 0.05). Furthermore, Se-chitosan at concentrations of 0.2 and 0.4 mg/kg demonstrated both linear and quadratic increases in albumen height, Haugh unit, and yolk color in fresh eggs compared to the control group. Additionally, Se-chitosan contributed to enhanced shell thickness and strength, along with an increased Se concentration in the yolk. Se-chitosan supplementation at different levels linearly and quadratically reduced coliforms (COL) while increasing lactic acid bacteria (LAB)/coliform ratios (P < 0.05). Se-chitosan supplementation linearly and quadratically increased the total antibody response to sheep red blood cells (SRBC) and IgG titers (P < 0.05). It also linearly decreased the level of malondialdehyde in fresh and stored egg yolks and increased the activity of antioxidant enzymes catalase and glutathione peroxidase linearly, and superoxide dismutase (SOD) both linearly and quadratically in quail blood serum (P < 0.05). Additionally, supplementation of Se-chitosan at levels of 0.2 and 0.6 mg/kg linearly decreased the ∑ n-6 PUFA/∑ n-3 PUFA ratio in the yolk compared to the control group (P < 0.05). It can be concluded that incorporating Se-chitosan as a novel organic source of Se in the diet of laying quails can enhance production performance, egg quality, egg Se concentration, yolk lipid oxidation, microbial population, immune response, antioxidant enzyme activity, and yolk fatty acid profile.

Feeding a Novel Mannan-Rich Yeast Carbohydrate Product Improves Production Performance and Humoral Immunity of Broiler Chickens.

The current study examined the benefits of a novel mannan-rich yeast carbohydrate product (YM) on broiler chicken growth performance and immune response against sheep red blood cells (SRBCs). A total of 144 newly hatched male Cornish cross broiler chicks were randomly assigned to four treatments with 12 cages per treatment and three birds per cage. The treatments were (1) control, basal diet; (2) YCW, basal diet + 1 g/kg yeast cell wall; (3) YM1, basal diet + 0.5 g/kg of a novel yeast mannan-rich product (YM); and (4) YM2, basal diet + 1 g/kg YM. Growth performance was measured at 14, 28, and 35 days of age (d). At 26 and 27 d, nine birds per treatment were immunized intravenously with SRBCs, and antibody responses against SRBCs were analyzed through a hemagglutination assay 7 days post-inoculation. Supplementing YM tended to improve broiler chicken weight gain from 29 to 35 d (p = 0.053). An improvement in the feed conversion ratio (FCR) was observed in the birds fed YM diets during 29-35 d and over the entire experimental period (0-35 d; p < 0.05). Furthermore, birds fed YM2 diets had more robust antibody responses against SRBCs than the control birds (p = 0.033). In conclusion, dietary supplementation of YM improved broiler chicken growth performance and antibody response against SRBCs.

Impact of cow, buffalo, goat or camel milk consumption on oxidative stress, inflammation and immune response post weaning time

Milk is a whitish liquid that is secreted from mammary glands; and considered as the primary source of nutrition for newborns since they are not able to digest solid food. However, it contains primary nutrients, as well as growth and immune factors. Early weaning is a critical issue that face women and their babies in developing countries. To avoid infant malnutrition, they tend to use other milk types instead of baby formula. Therefore, the present study aimed to evaluate the impact of cow, buffalo, goat or camel milk consumption on oxidative stress, inflammation and immune response in male and female Sprague Dawley rats post weaning time. The amino acids, fatty acids, minerals and vitamins in the tested milk types were evaluated. Animals were divided into 5 groups (control, cow, buffalo, goat and camel milk administrated groups) (10 rats/group); each animal was administrated by 3.4 ml/day. Rats were administered with milk for 6 weeks; at the end of the 5th week, five animals of each group were isolated and the remaining five animals were immunized with sheep red blood cells (SRBCs) and kept for another week to mount immune response. The effect of different milk types on rats’ immune response towards SRBCs was evaluated through pro-inflammatory cytokines, antioxidants, ESR and CRP measurement; together, with the histopathological examination of spleen samples and hemagglutination assay. Camel milk consumption reduced oxidative stress and inflammation in spleen that resulted from SRBCs immunization; in addition to, B cell stimulation that was apparent from the high level of anti-SRBCs antibodies. Camel milk is recommended for newborn consumption, due to its high-water content, unsaturated fatty acids, and vitamin C, as well as low lactose and fat content.

Antimicrobial and Antiplasmodial Activities of Endophytic Fungi Associated with Psidium guajava

Infections due to antimicrobial-resistant microorganisms have become widespread in recent years. Thus, searching for novel antimicrobial agents to combat such pathogens has become crucial. The current study aimed to evaluate the antimicrobial, antiplasmodial, and immunomodulatory activities of the extracts of endophytic fungi isolated from Psidium guajava. Isolation, identification, fermentation, and extraction of the secondary metabolites of the fungal endophytes were carried out following standard procedures. The extracts were subjected to High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) analysis to detect their bioactive components. The Antimicrobial activity and Minimum Inhibitory Concentration of the fungal extracts were evaluated against pure cultures of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumonia using Agar well diffusion and Agar dilution method respectively. The acute toxicity study (LD50) was carried out using Lorke’s method. The extracts were tested in vivo in mice for antiplasmodial activity against Plasmodium berghei and in vitro against Plasmodium falciparum using Peter and Reyley's curative test method and WHO standardized micro-test system with modification respectively. The immunomodulatory activity of the extracts was evaluated by cyclophosphamide-induced myelosuppression (hematological parameters). Active extracts were further subjected to Delayed-Type Hypersensitivity Response (DTHR) and Haemagglutination Inhibition Assay using Sheep Red Blood Cells as antigens. The result showed Alternaria sp. (PGL1, PGL2, PGL3), from P. guajava. The HPLC-DAD analysis revealed the presence of bioactive compounds previously reported to have antimicrobial, antiplasmodial, and immunomodulatory properties. The fungal extracts exhibited varying degrees of antimicrobial activity. The LD50 of the fungi extracts was&gt;5000 mg/kg in mice. The extracts at 100 and 200 mg/kg body weight in mice showed varying degrees of antiplasmodial activity. Growth of P. berghei was significantly (p&lt;0.001) inhibited, curative effect ranges from 59.09 – 100%. Schizont maturation of P. falciparum isolates was inhibited and the highest level of inhibition was observed at 1 mg/ml (p&lt;0.05). The fungal extracts reversed the effect of cyclophosphamide-induced reduction in total white blood cell counts and % neutrophil. This study showed that the tested plant harbors species of endophytic fungi that contain numerous secondary metabolites. The endophytic fungi showed prophylactic, immunostimulatory, and antiplasmodial activities, which can be exploited to develop antimicrobial, antiplasmodial, and immunomodulatory agents.

Effect of different levels of single cell protein and probiotic microorganisms on performance, immunological responses, and intestinal histology in laying hens

AbstractAn experiment was conducted to evaluate the effects of single‐cell protein (SCP), as a valuable by‐product and substitute for soybean meal, and multistrain probiotics on the performance, blood biochemistry, intestinal histomorphology, ileal microbiota, and immune responses in laying hens. Leghorn laying hens were randomly assigned to nine experimental treatments with eight replicates of five birds each. Dietary treatments consisted of three levels of replacement of soybean meal with SCP (0.0%, 30%, and 60%) and three levels of probiotics (0.0, 50, 100 mg/kg) offered through 70 days of main recording. The result indicated that replacing 30% soybean meal with SCP in the diet significantly increased the eggshell weight, thickness, and strength; however, hens receiving 60% SCP replacement showed lower productive performance. During the second 35‐d trial, hens receiving at least 50 mg/kg probiotics produced higher eggshell weight, thickness, and strength than the control hens. Remarkable lower levels of serum cholesterol content were observed in the SCP and probiotic‐supplemented diets. The significant reduction in the ileal pH, Escherichia coli and Clostridium spp. enumerations and a remarkable increase in Lactobacillus count was observed after feeding incremental levels of probiotics. The highest villus height to crypt depth ratio, antibody titer against sheep red blood cells (in secondary response) and Newcastle disease vaccine, as well as egg production and egg mass, were found in the hens that received 30% SCP replacement in combination with 50 or 100 mg/kg probiotic (SCP × Probiotic). The present study concluded that feeding SCP, as a cheap protein alternative source, along with probiotics while reducing production costs can support productive performance via modulating the intestinal microbiomes and health indices and fortifying the immune system in laying hens.

Eliminating extracellular autoinducing peptide signals inhibits the Staphylococcus aureus quorum sensing agr system

An accessory gene regulator (agr) in the quorum sensing (QS) system in Staphylococcus aureus contributes to host infection, virulence factor production, and resistance to oxidative damage. Artificially maintaining the inactive state of agr QS impedes the host infection strategy of S. aureus and inhibits toxin production. The QS system performs intercellular signal transduction, which is activated by the mature autoinducer peptide (AIP). It is released from cells after AgrD peptide processing as an intercellular signal associated with increased bacterial cell density. This study evaluated the effectiveness of inhibiting agr QS wherein AIP trap carriers were made to coexist when culturing Staphylococcus aureus. Immersing a nitrocellulose (NC) membrane in Staphylococcus aureus ATCC 12600 culture inhibited QS-dependent α-hemolysin production, which significantly reduced the hemolysis ratio of sheep red blood cells by the culture supernatant. A quartz crystal microbalance analysis supported AIP adsorption onto the NC membrane. Adding the NC membrane during culture was found to maintain the expression levels of the agr QS gene agrA and α-hemolysin gene hla lower than that when it was not added. Eliminating extracellular AIP signals allowed agr QS to remain inactive and prevented QS-dependent α-hemolysin expression. Isolating intercellular signals secreted outside the cell is an effective strategy to suppress gene expression in bacterial cells that collaborate via intercellular signaling.

Immunoregulatory and antioxidant properties of tryptophan in quail chick

A dose-response assay was carried out to investigate the effects of graded levels of dietary tryptophan (Trp) on blood variables, immunity, and meat quality in quail chicks during the last two weeks of the growing period. A total of 420 21-day-old quail chicks were randomly distributed across the seven experimental groups (i.e., 2.12, 2.25, 2.38, 2.51, 2.64, 2.77, and 2.90 g Trp/kg of diet) with four pen replicates of 15 birds each. Blood variables, including uric acid (UA), albumin (ALB), and triglycerides (TG), responded inversely to increasing dietary Trp (P < 0.001). The concentration of aspartate aminotransferase (AST) in serum, the relative weight of bursa of Fabricius (BF), immunoglobulin G (IgG), water holding capacity (WHC), and antigen production against the sheep red blood cells (SRBC) increased with increasing dietary Trp (P < 0.001). In contrast, the concentration of malondialdehyde (MDA) and drip loss in meat samples decreased with increasing dietary Trp (P < 0.001). The best models for optimal dietary Trp were identified based on a statistical merit basis known as the model accuracy index (δ). The estimated dietary Trp for optimizing ALP, UA, total protein (TP), TG, SRBC, IgG, BF, drip loss, WHC, and MDA were obtained at 2.347, 2.371, 2,372, 2.485, 2,691, 2.738, 2.306, 2.359, 2.247, and 2.500 g/kg of diet, respectively. Principal component analysis showed that UA, TG, IgG, and drip loss had a higher association with dietary Trp rather than other responses. Considering the high δ and eigenvalues of the models, the best estimation of dietary Trp level required for the optimization of the studied traits in quail chicks would be 2.738 g Trp/kg of diet, which was significantly higher than that recommended for the quail performance by NRC (1994).

Effects of replacing Na selenite in laying hen feed with selenized glucose on production performance, egg quality, egg selenium content, microbial population, immunological response, antioxidant enzymes, and fatty acid composition

This study aimed to explore the effects of selenized glucose (SeGlu) and Na selenite supplementation on various aspects of laying hens such as production performance, egg quality, egg Se concentration, microbial population, antioxidant enzymes activity, immunological response, and yolk fatty acid profile. Using a 2 × 2 factorial design, 168 laying hens at 27-wk of age were randomly divided into 4 treatment groups with 7 replications. Se source (Na selenite and SeGlu) and Se level (0.3 and 0.6 mg/kg) were used as treatments. When 0.3 mg SeGlu/kg was compared to 0.3 mg Na selenite/kg, the interaction findings revealed that 0.3 mg SeGlu/kg increased egg production percent and shell ash (P < 0.05). When compared to 0.3 mg Na selenite/kg, dietary supplementation with 0.3 and 0.6 mg SeGlu/kg resulted in an increase in albumen height, Haugh unit, and yolk color of fresh eggs (P < 0.05). SeGlu enhanced albumen height, Haugh unit, shell thickness (P < 0.01), albumen index, yolk share, specific gravity, shell ash (P < 0.05) of fresh eggs and shell thickness (P < 0.05) of stored eggs as compared to Na selenite. The interaction showed that 0.6 mg SeGlu/kg enhanced yolk Se concentration while decreasing malondialdehyde levels in fresh egg yolk (P < 0.05). SeGlu enhanced Se concentration in albumen and glutathione peroxidase activity in plasma (P < 0.05) as compared to Na selenite. 0.6 mg Se/kg increased lactic acid bacteria, antibody response to sheep red blood cells, and lowered ∑n-6 PUFA/ ∑n-3 PUFA ratio (P < 0.05). As a result, adding SeGlu to the feed of laying hens enhanced egg production, egg quality, egg Se concentration, fresh yolk lipid oxidation, and glutathione peroxidase enzyme activity.