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1.
PLoS One ; 19(1): e0296987, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277423

RESUMO

Nuclear energy (NE) is seen as a reliable choice for ensuring the security of the world's energy supply, and it has only lately begun to be advocated as a strategy for reducing climate change in order to meet low-carbon energy transition goals. To achieve flexible operation across a wide operating range when it participates in peak regulation in the power systems, the pressurised water reactor (PWR) NE systems must overcome the nonlinearity problem induced by the substantial variation. In light of this viewpoint, the objective of this work is to evaluate the reactor core (main component) of the NE system via different recent optimization techniques. The PWR, which is the most common form, is the reactor under investigation. For controlling the movement of control rods that correspond with reactivity for power regulation the PWR, PID controller is employed. This study presents a dynamic model of the PWR, which includes the reactor core, the upper and lower plenums, and the piping that connects the reactor core to the steam alternator is analyzed and investigated. The PWR dynamic model is controlled by a PID controller optimized by the gold rush optimizer (GRO) built on the integration of the time-weighted square error performance indicator. Additionally, to exhibit the efficacy of the presented GRO, the dragonfly approach, Arithmetic algorithm, and planet optimization algorithm are used to adjust the PID controller parameters. Furthermore, a comparison among the optimized PID gains with the applied algorithms shows great accuracy, efficacy, and effectiveness of the proposed GRO. MATLAB\ Simulink program is used to model and simulate the system components and the applied algorithms. The simulation findings demonstrate that the suggested optimized PID control strategy has superior efficiency and resilience in terms of less overshoot and settling time.


Assuntos
Odonatos , Água , Animais , Algoritmos , Simulação por Computador , Vapor
2.
PLoS One ; 18(11): e0293613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37922271

RESUMO

Solar energy, a prominent renewable resource, relies on photovoltaic systems (PVS) to capture energy efficiently. The challenge lies in maximizing power generation, which fluctuates due to changing environmental conditions like irradiance and temperature. Maximum Power Point Tracking (MPPT) techniques have been developed to optimize PVS output. Among these, the incremental conductance (INC) method is widely recognized. However, adapting INC to varying environmental conditions remains a challenge. This study introduces an innovative approach to adaptive MPPT for grid-connected PVS, enhancing classical INC by integrating a PID controller updated through a fuzzy self-tuning controller (INC-FST). INC-FST dynamically regulates the boost converter signal, connecting the PVS's DC output to the grid-connected inverter. A comprehensive evaluation, comparing the proposed adaptive MPPT technique (INC-FST) with conventional MPPT methods such as INC, Perturb & Observe (P&O), and INC Fuzzy Logic (INC-FL), was conducted. Metrics assessed include current, voltage, efficiency, power, and DC bus voltage under different climate scenarios. The proposed MPPT-INC-FST algorithm demonstrated superior efficiency, achieving 99.80%, 99.76%, and 99.73% for three distinct climate scenarios. Furthermore, the comparative analysis highlighted its precision in terms of control indices, minimizing overshoot, reducing rise time, and maximizing PVS power output.


Assuntos
Fontes de Energia Elétrica , Modelos Teóricos , Simulação por Computador , Algoritmos , Lógica Fuzzy
3.
Vet Microbiol ; 284: 109816, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37348210

RESUMO

Riemerella anatipestifer (RA) is a common disease causing economic losses to duck farms worldwide. Novel supplements are crucially needed to control this bacterium, enhance poultry performance, and produce synergistic effects with vaccines in stimulating the immune system. This study investigated the effect of nano-selenium (Nano-Se) on the vaccinated (VAC) and challenged (Ch) Pekin ducklings (Anas platyrhynchos) with RA. Five experimental groups (G1-G5) were included in this study: G1 was the control group, G2 was the RA-challenged group, G3 was the Nano-Se+Ch group, G4 was the VAC+Ch group, and G5 was the Nano-Se+VAC+Ch group. The Nano-Se (0.3 mg/kg diet) was supplemented for 5 weeks post-vaccination (PV). The ducklings were vaccinated subcutaneously with the RA vaccine at 7 days of age and challenged with RA at the 3rd week PV. Blood, pharyngeal swabs and tissue samples were collected at the 3rd week PV and at different times post-challenge (PC). The growth performance (weight gain and feed conversion ratio), clinical signs, gross lesions, mortality, bacterial shedding, haematological, immunological, and biochemical parameters, cytokines production, and histopathological lesion scores showed significant differences (P < 0.05) between the challenged (G2) group and the supplemented (G3 & G5) groups. G5 showed the highest (P < 0.05) growth performance, phagocytic activity, IgM and IgG, splenic interleukin-2 (IL-2), IL-10, and interferon-gamma (IFN-γ) gene expressions, and the lowest mortality, bacterial shedding, hepatic and renal damage, heterophil/lymphocyte ratio and lesion scores compared to the other groups. In conclusion, the supplementation of nano-selenium for five weeks in the diet can improve the growth performance, immune status, and cytokines production in ducklings vaccinated and challenged with RA.


Assuntos
Doenças das Aves Domésticas , Riemerella , Selênio , Animais , Patos/microbiologia , Doenças das Aves Domésticas/microbiologia , Selênio/farmacologia , Riemerella/genética , Suplementos Nutricionais
4.
BMC Vet Res ; 18(1): 408, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401270

RESUMO

AIM: This study evaluated the effect of co-administration of vitamin C and Arabic gum (AG) supplements on the response of vaccinated (VAC) and challenged laying Japanese quails with avian influenza virus (AIV) H9N2. MATERIALS AND METHODS: One hundred and fifty 49-day-old laying Japanese quails were divided into 5 groups (G1-G5): the G1 group was a negative control, G2 group was unvaccinated + H9N2 challenged (Ch), G3 group was unvaccinated + supplements + Ch, G4 group was VAC + Ch, and the G5 group was VAC + supplements + Ch. The supplements (vitamin C, 1 g/liter of drinking water and AG, 1% ration) were given for 5 weeks post-vaccination (PV). The birds were injected subcutaneously with an inactivated H9N2 vaccine at 49 days of age. The quails were then challenged intranasally with AIV H9N2 at the 3rd week PV. Blood, tracheal swab and tissue samples were collected at the 1st, 2nd, and 3rd weeks PV, and at different time points post-challenge (PC). RESULTS: Growth performance, egg production (%), egg and eggshell weights, HI antibody titers, clinical signs, lesions, mortality, virus shedding rates, leukogram, biochemical and immunological parameters and histopathological lesions PC showed significant differences (P < 0.05) between the vaccinated-unsupplemented (G4) group and the vaccinated-supplemented (G5) group. G5 showed the highest (P < 0.05) growth performance, egg production, HI antibody titers, and heterophil phagocytic activity and the lowest heterophil/lymphocyte (H/L) ratio, mortality, virus shedding rates, creatinine level and histopathological lesion scores in the lungs. CONCLUSION: The co-administration of vitamin C and AG for 5 weeks can improve growth performance, egg production and the immune response in vaccinated laying quails challenged with AIV H9N2.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Animais , Coturnix , Ácido Ascórbico/farmacologia , Galinhas , Óvulo , Vacinas de Produtos Inativados
5.
Vet Res Commun ; 46(2): 419-430, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34846629

RESUMO

This study evaluated the diuretic, antioxidant, anti-inflammatory, and immunological effects of a commercial diuretic (CD) (composed of ammonium chloride, potassium citrate, sodium chloride, ascorbic acid, biotin, halfa bar extract, and hexamine) on chickens with induced urolithiasis. A total of 100 one-day-old white Hy-Line chicks were fed a basal diet containing 20% crude protein (CP) and 1% Ca until they reached 48 days of age. Then, the birds were divided into five groups (G1-G5). G1 was fed a basal diet and kept as a negative control, G2 was fed a high protein (HP) diet containing 25% crude protein, G3 was fed high calcium (HC) diet containing 5% Ca, G4 was fed HP diet supplemented with CD, and G5 was fed HC diet supplemented with CD. The CD was supplemented with drinking water (at a dose of 0.5 ml/ liter) for 1 week. The experiment was held for 78 days. Clinical signs, postmortem lesions, and mortality rates were observed. Biochemical analytes, redox status biomarkers, and expression of interleukin-6 (IL-6) and interferon-gamma (IFN-γ) were measured. Tissue samples were taken for histopathological examination. No signs of CD toxicity were observed during the toxicity test prior to the experiment. Compared to all groups, birds in G2 and G3 showed impaired renal function and alterations in biochemical, redox status, lipid peroxidation, post-mortem, and histopathological lesions along with upregulation of IL-6 and IFN-γ in the kidney and spleen. In conclusion, commercial diuretic supplementation for one week improves renal function, redox status, immune and anti-inflammatory responses in chickens with induced urolithiasis.


Assuntos
Galinhas , Urolitíase , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Diuréticos/metabolismo , Diuréticos/farmacologia , Diuréticos/uso terapêutico , Interleucina-6/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Urolitíase/induzido quimicamente , Urolitíase/tratamento farmacológico , Urolitíase/veterinária
6.
Vet Res Commun ; 46(2): 363-376, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34755272

RESUMO

Florfenicol (FFC) is a synthetic broad-spectrum antibiotic and garlic has a bactericidal action against coliforms. This study was carried out to compare the antimicrobial, immunological and biochemical effects of florfenicol and garlic, for their ability to treat enteropathogenic Escherichia coli serotype O55: H7 infection in rabbits. Four groups (G1-G4) were included. G1 group was the negative control; G2 group was the infected with a field-isolated strain of E. coli and untreated; G3 group was the infected+treated with FFC for 5 days; and G4 group was the infected+treated with garlic tablets for 14 days. The rabbits were observed for clinical signs, growth performance and mortality rates. Garlic-infused disks had a larger clear zone of inhibition than other antibiotic disks. Garlic treatment improved growth performance, biochemical parameters, and immunological response and reduced the fecal shedding and histopathological lesions in E. coli O55: H7 infected rabbits compared to the other groups. Colonization of E. coli more rapidly declined in G3 & G4 than in G2. Hepatic and intestinal gene expressions; tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were significantly elevated in G2 compared to the other groups, and their levels were elevated more in G3 than in G4. Serum interferon-gamma (IFN-γ) and phagocytic activity were significantly elevated in G4 compared to G3. G3 revealed macrocytic hypochromic anaemia that was confirmed histopathologically by moderate haematopoiesis of the bone marrow. In conclusion, garlic powder can reduce rabbit colibacillosis, like FFC, and can enhance the immune status of rabbits.


Assuntos
Alho , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antioxidantes , Escherichia coli , Alho/química , Coelhos , Sorogrupo , Tianfenicol/análogos & derivados
7.
J Anim Physiol Anim Nutr (Berl) ; 105(1): 129-139, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32790029

RESUMO

This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions; biochemical, redox status and histopathological alterations; and upregulation of inflammatory cytokines (interleukin (IL)-1ß and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens.


Assuntos
Galinhas , Urolitíase , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cálcio da Dieta , Dieta/veterinária , Suplementos Nutricionais , Estresse Oxidativo , Urolitíase/veterinária
8.
Trop Anim Health Prod ; 52(6): 3819-3831, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33006042

RESUMO

This study was conducted to investigate the molecular characterization and pathogenicity of very virulent infectious bursal disease virus (vvIBDV) isolated from naturally infected turkey poults and possible spread to chickens. Thirty samples were collected from turkey poults in the vicinity or in the same backyards with chickens suspected to be infected with IBDV and from live bird markets from different localities in Dakahlia governorate, Egypt. There were no obvious clinical signs in tested turkey poults except dehydration and whitish diarrhoea in some birds with no mortality, and post-mortem lesions were observed in few birds as atrophied bursae, nephritis and petechial haemorrhages on thigh muscles. Reverse transcription polymerase chain reaction (RT-PCR), histopathological examination and immunohistochemistry were used for identification of the IBDV. Out of 30 tested samples, 17 samples (56.7%) were positive by RT-PCR. Phylogenetic analysis of VP2 gene of two selected IBDV strains (turkey 1 and turkey 2) showed a close genetic relationship to vvIBDV strains (serotype 1) isolated from chickens in Egypt and other countries with 93.1 to 95.99% identity for turkey 1 strain and 95.54 to 98.51% for turkey 2 strain. Both turkey 1 and turkey 2 strains were closely related to the Nigerian vvIBDV strain isolated from turkeys with 95.78% and 96.37% identity, respectively. Sequence analysis of both strains demonstrated that they have conserved amino acid residues of vvIBDV (I242, I294 and S299) and Y220F amino acid substitution which is very common in Egyptian vvIBDV chicken strains, while Turkey 1 strain has amino acid substitutions at A222P and I256V. Histopathological examination showed marked depletion of bursal lymphoid tissue. In conclusion, for the first time in Egypt, the molecular characterization and pathogenicity confirmed the presence of natural infection of turkey poults with vvIBDV (serotype 1) with possible spread to chickens causing severe economic losses.


Assuntos
Infecções por Birnaviridae/veterinária , Vírus da Doença Infecciosa da Bursa/patogenicidade , Doenças das Aves Domésticas/virologia , Perus , Animais , Infecções por Birnaviridae/epidemiologia , Infecções por Birnaviridae/virologia , Egito , Filogenia , Doenças das Aves Domésticas/epidemiologia , Proteínas Estruturais Virais/genética , Virulência
9.
Avian Pathol ; 49(5): 496-506, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32835500

RESUMO

Salmonella and avian influenza virus are important pathogens affecting the poultry industry and human health worldwide. In this experimental study, we evaluated the consequences of co-infection of Salmonella enteritidis (SE) with H9N2 avian influenza virus (H9N2-AIV) in chickens. Four groups were included: control group, H9N2-AIV group, H9N2-AIV + SE group, and SE group. Infected chickens were intranasally inoculated with H9N2-AIV at 21 days of age and then orally administered SE on the same day. The birds were monitored for clinical signs, mortality rates, and alterations in body weight. Sera, intestinal fluids, oropharyngeal, and cloacal swabs, and tissue samples were collected at 2, 6, 10, and 14 days post-infection (dpi). Significant increases in clinical signs and mortality rates were observed in the H9N2-AIV + SE group. Moreover, chickens with co-infection showed a significant change in body weight. SE faecal shedding and organ colonization were significantly higher in the H9N2-AIV + SE group than in the SE group. H9N2-AIV infection compromised the systemic and mucosal immunity against SE, as evidenced by a significant decrease in lymphoid organ indices as well as systemic antibody and intestinal immunoglobulin A (IgA) responses to SE and a significant increase in splenic and bursal lesion scores. Moreover, SE infection significantly increased shedding titres and duration of H9N2-AIV. In conclusion, this is the first report of co-infection of SE with H9N2-AIV in chickens, which leads to increased pathogenicity, SE faecal shedding and organ colonization, and H9N2-AIV shedding titre and duration, resulting in substantial economic losses and environmental contamination, ultimately leading to increased zoonoses.


Assuntos
Galinhas/microbiologia , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/fisiologia , Animais , Coinfecção/veterinária , Fezes/microbiologia , Imunoglobulina A/imunologia , Influenza Aviária/mortalidade , Intestinos/microbiologia , Doenças das Aves Domésticas/mortalidade , Distribuição Aleatória , Salmonelose Animal/mortalidade , Eliminação de Partículas Virais
10.
Comp Immunol Microbiol Infect Dis ; 72: 101505, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32563798

RESUMO

This study was conducted to assess the comparative effects of a mixed herbal extract (MHE) containing Ocimum sanctum, Withania somnifera, Emblica officinalis, Tinospora cordifolia, Mangifera indica, and Asphaltum (shilajit) on infectious bursal disease virus (IBDV)-vaccinated (VAC) chickens infected with IBDV and avian influenza virus (AIV) H9N2. The experiment included three groups (G1-G3): G1, the negative control group; G2, the VAC + challenged (Ch) group; and G3, the VAC + Ch + MHE group. MHE was orally administered continuously for 5 weeks post-vaccination (PV) with IBDV at 12 days of age, and the chicks were simultaneously challenged with virulent IBDV (intraocularly) and AIV H9N2 (intranasally) at 21 days PV. Blood and tissue samples as well as tracheal and cloacal swabs were gathered at different times PV and post-challenge. Immunological and haematological parameters, histopathological lesions, relative organ weights and final live weights revealed significant differences (P ≤ 0.05) between G2 and G3 groups. Furthermore, in the G3 group, the protection rates, ELISA and HI titers and CD4+/CD8+ ratio were significantly increased, whereas viral shedding titers and the heterophil/lymphocyte ratio were decreased. In conclusion, the oral administration of the mixed herbal extract for 5 weeks can stimulate the immune response to IBDV vaccination and relieves the pathogenicity of an AIV H9N2 and IBDV co-infection in chickens.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vírus da Doença Infecciosa da Bursa , Influenza Aviária , Extratos Vegetais/imunologia , Doenças das Aves Domésticas , Vacinas Virais , Administração Oral , Animais , Anticorpos Antivirais , Galinhas/imunologia , Coinfecção/veterinária , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/tratamento farmacológico , Influenza Aviária/prevenção & controle , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/prevenção & controle
11.
Eur J Contracept Reprod Health Care ; 25(2): 120-125, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31990231

RESUMO

Objectives: The aim of the study was to investigate the effect of copper-bearing intrauterine device (IUD) use on the virulence of Candida species causing vulvovaginal candidiasis (VVC). The in vitro ability of Candida species to produce proteinase and phospholipase enzymes was studied, together with their antifungal susceptibility.Methods: Vaginal swabs from women with VVC were cultured and Candida species were identified. Participants comprised 132 women with culture-confirmed VVC, of whom 65 were using a copper-bearing IUD and 67 were not. Candida isolates were tested for their ability to produce proteinase and phospholipase as well as for their susceptibility to fluconazole and nystatin.Results: Proteinase production was higher in non-albicans Candida (NAC) isolates of IUD users compared with non-users (p = 0.017). IUD use was significantly associated with antifungal resistance of NAC isolates to fluconazole (p = 0.013) and nystatin (p = 0.018). By contrast, IUD use seemed to significantly reduce the production of proteinase by C. albicans (p = 0.041), with no effect on its antifungal susceptibility. There was a significant negative correlation between proteinase production in both C. albicans and NAC as well as sensitivity to fluconazole (r= -0.383, p < 0.05 and r= -0.497, p < 0.05, respectively).Conclusion: IUD use enhanced the virulence (proteinase production and antifungal resistance) of NAC but not C. albicans, indicating a variation in virulence between Candida species in response to IUD use. C. albicans responded better to fluconazole, whereas NAC isolates were more sensitive to nystatin.


Assuntos
Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Dispositivos Intrauterinos de Cobre/efeitos adversos , Adulto , Candida/metabolismo , Estudos Transversais , Egito , Feminino , Humanos , Peptídeo Hidrolases/biossíntese , Fosfolipases/biossíntese , Virulência
12.
Comp Immunol Microbiol Infect Dis ; 68: 101378, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812120

RESUMO

The objective of this study was to evaluate the efficacy of Herba Cox®, a commercial herbal compound containing extracts from Bombax malabaricum, Aegle marmelos, Anethum foeniculum, Resina salvia, Ferula asafoetida and Papaver somniferum, for the treatment of rabbit hepatic coccidiosis. Thirty rabbits were allocated into three groups (10 × 3), the G1 group served as a negative control group, G2 group (positive control group) was infected with 5 × 104 sporulated E. stiedaeoocysts and served as infected-untreated group, and G3 group was infected with 5 × 104 sporulated E. stiedaeoocysts and treated with Herba Cox®, 1 ml/liter of drinking water, starting 7 days before infection and continuing for 4 weeks post-infection. When compared to the infected group (G2), body weight and weight gain were significantly (P ≤ 0.05) increased, the feed conversion rate was improved and no mortality was detected in infected treated group (G3) and similar to negative control group (G1). In addition, faecal oocyst output and liver enzymes were significantly decreased. Malondialdehyde, nitric oxide, and glutathione concentrations observed in G3 were similar to those in G1. In infected-untreated rabbits (G2), the haemoglobin, lymphocytes, and CD4+/ CD8+ ratio were significantly decreased, while the total leukocyte count, percentage of heterophils, and heterophil/lymphocyte ratio were increased. Significantly more severe histopathological hepatic lesions were observed in G2 when compared to G1 and G3. In conclusion, the obtained results showed that Herba Cox® should be considered a safe and novel effective compound for the treatment of E. stiedae infection in rabbits.


Assuntos
Coccidiose/tratamento farmacológico , Fígado/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Eimeria , Fezes/parasitologia , Feminino , Hepatite/tratamento farmacológico , Hepatite/parasitologia , Fígado/parasitologia , Masculino , Coelhos
13.
Artigo em Inglês | MEDLINE | ID: mdl-31712184

RESUMO

This study was performed to evaluate the effects of omega-3 supplementation on growth performance, clinical signs, post-mortem lesions, haemagglutination inhibition (HI) antibody titres, gene expression and histopathology in quails (Coturnix coturnix japonica) infected with Newcastle disease virus (NDV) and avian influenza virus (AIV) H9N2. One hundred, 40-day-old male quails were divided into 5 groups: G1, fed a control basal diet; G2A, infected with NDV; G2B, infected with H9N2; G3A, infected with NDV and given omega-3, and G3B, infected with H9N2 and given omega-3. The dietary omega-3 supplementation was continued for 4 weeks: two weeks before infection and two weeks after intranasal infection with virulent NDV and AIV H9N2. Our results revealed significant differences (P < 0.05) in growth performance, HI antibody titres, clinical signs, post-mortem lesions, mortality, viral shedding rates, immunological parameters, and histopathological lesions between the treated (G3A and G3B) and untreated (G2A and G2B) groups. In conclusion, dietary omega-3 supplementation for 4 weeks can improve growth performance and alleviate the deleterious immunological and pathological effects of NDV and AIV H9N2 infection in quails.


Assuntos
Coturnix/crescimento & desenvolvimento , Coturnix/virologia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle , Animais , Coturnix/imunologia
16.
Vet Microbiol ; 238: 108429, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31648721

RESUMO

Viral haemorrhagic disease (VHD) and colibacillosis are common diseases in rabbits that cause economic losses worldwide. The effect of colibacillosis on the immune response of vaccinated rabbits against rabbit haemorrhagic disease virus (RHDV) was studied. Four groups (G1-G4) were included. G1 was the negative control group; G2 was the RHDV vaccine group; G3 was the E. coli-infected group; and G4 was the E. coli-infected + RHDV vaccine group. The E. coli infection and RHDV vaccination were simultaneously performed, with another previous infection, 3 days before vaccination. At 28 days post-vaccination (PV), the rabbits (G2-G4) were challenged intramuscularly with 0.5 ml of RHDV at a dose of 103 50% median lethal dose (LD50)/rabbit. The rabbits were observed for clinical signs, body weight gain and mortality rates. Tissue, blood, serum, and faecal samples and rectal swabs were collected at 3, 5, 7, 14, 21 and 28 days PV. Significant clinical signs and mortality and a decrease in BW were observed in the infected + RHDV vaccine group. On the 3rd day post-infection (PI), compared with all the other groups, the vaccinated group (G2) had significantly upregulated hepatic tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels; however, the infected + RHDV vaccine group had significantly higher intestinal levels of TNF-α and IL-6 than the other groups. Furthermore, E. coli infection in vaccinated rabbits led to immunosuppression, as shown by significant decreases (P < 0.05) in heterophil phagocytic activity, the CD4+/CD8+ ratio, and HI antibody responses to RHDV and a significant increase in the heterophil to lymphocyte (H/L) ratio. In conclusion, colibacillosis leads to immunosuppression involving a shift in the equilibrium of cytokines and reduced weight gain and mortality in vaccinated rabbits and could be a contributing factor in RHDV vaccination failure in rabbit farming.


Assuntos
Infecções por Caliciviridae/veterinária , Infecções por Escherichia coli/veterinária , Coelhos/imunologia , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/mortalidade , Citocinas/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/mortalidade , Infecções por Escherichia coli/fisiopatologia , Regulação da Expressão Gênica/imunologia , Vírus da Doença Hemorrágica de Coelhos/imunologia , Coelhos/microbiologia , Coelhos/virologia , Vacinação/normas
17.
Comp Immunol Microbiol Infect Dis ; 65: 165-175, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31300109

RESUMO

Avian influenza vaccines are commonly used in the poultry industry, and some medicinal plants can increase the efficacy of such vaccines. The objective of this study was to evaluate the effect of Immulant® (IMU) (a commercial product based on Echinacea and Nigella sativa) on stress induced by dexamethasone (DEX) in chickens vaccinated (VAC) against the H9N2 avian influenza virus (AIV-H9N2). Seven experimental groups were included: the negative control, VAC, DEX, VAC + DEX, VAC + DEX + IMU, VAC + IMU and IMU groups. The vaccinated chickens (at 10 days of age) were injected daily with DEX for three days pre-vaccination and for three days pre-challenge and orally administered 1% IMU for 6 weeks post-vaccination (PV). The chickens were then challenged intranasally with AIV-H9N2 at 28 days PV. Serum, blood, tracheal and cloacal swabs and tissue samples were collected in the 1st and 4th weeks PV and at different time points post-challenge. The results showed significant changes (P ≤ 0.05) in oxidative stress and antioxidant biomarkers (malondialdehyde, nitric oxide and reduced glutathione), haematological and immunological parameters, final live weights, relative organ weights and histopathological lesions between the VAC+DEX group and the VAC group. Moreover, IMU significantly increased protection rates post-challenge, HI antibody titers and heterophil phagocytic activity and decreased DEX-induced stress and virus shedding titers. In conclusion, oral administration of 1% IMU for six weeks can enhance the immune response after AI-H9N2 vaccination and reduce the pathogenicity of infection in stressed chickens.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Galinhas/imunologia , Echinacea/química , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vacinas contra Influenza/imunologia , Nigella sativa/química , Adjuvantes Imunológicos/química , Animais , Anticorpos Antivirais/sangue , Dexametasona/administração & dosagem , Terapia de Imunossupressão , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Aves Domésticas , Estresse Fisiológico , Virulência , Eliminação de Partículas Virais
18.
Artigo em Inglês | MEDLINE | ID: mdl-31174705

RESUMO

This study was conducted to perform the comparative molecular characterization of avian influenza virus (AIV) H9N2, pathogenicity and seroprevalence in commercial and backyard poultry flocks. Fifty commercial poultry flocks were investigated between 2012 and 2015. Eighteen flocks (36%) out of 50 were positive HA. Seven (38.9%) out of 18 were positive by chromatographic strip test for AI common antigen. By Real-time RT-PCR, only two flocks were positive H9. The molecular characterization of two different AI-H9N2 viruses, one isolated from a broiler flock (A/chicken/Egypt/Mansoura-18/2013) and the other from a layer flock (A/chicken/Egypt/Mansoura-36/2015) was conducted on HA gene. Moreover, a higher seroprevalence, using the broiler strain as a known antigen, was shown in backyard chicken flocks 15/26 (57.7%) than duck flocks 9/74 (12.2%). Interestingly, the pathogenicity index (PI) of the H9N2 broiler strain in inoculated experimental chickens ranged from 1.2 (oculonasal route) to 1.9 (Intravenous route). The PI indicated a highly pathogenic effect, with high mortality (up to 100%) in the inoculated chickens correlated with the high mortality (80%) in the flock where the virus was isolated. The firstly recorded clinical signs, including cyanosis in the combs and wattles and subcutaneous haemorrhages in the leg shanks and lesions, as well as histopathology and immunohistochemistry, revealed a systemic infection of the high pathogenicity with the H9N2 virus. Conversely, the H9N2 layer strain showed a low pathogenicity. In conclusion, as a first report, the molecular analysis and pathogenicity of the tested strains confirmed the presence of a high pathogenicity AIV-H9N2 with systemic infections.


Assuntos
Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Aves Domésticas/virologia , Animais , Galinhas/virologia , Cianose/virologia , Patos/virologia , Egito/epidemiologia , Influenza Aviária/mortalidade , Doenças das Aves Domésticas/mortalidade , Reação em Cadeia da Polimerase em Tempo Real , Estudos Soroepidemiológicos , Perus/virologia , Virulência
19.
Vet Microbiol ; 231: 24-32, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955817

RESUMO

Avian influenza virus (AIV) H9N2 infection causes economic losses on poultry farms, and immunostimulants are essential for improving chicken immunity. This study evaluated the immunological and pathological effects of vitamin E with Fetomune Plus® (a commercial product based on a yeast extract and vitamins) on chickens experimentally infected with AIV H9N2. Three groups of white Hy-Line chicks were included. The G1 group was kept as an uninfected untreated control, the G2 group was intranasally infected with the AIV H9N2 strain (0.5 ml of 106 50% egg infectious dose (EID50)), and the G3 group was infected and treated with vitamin E (200 mg/kg of diet) and Fetomune Plus® (1 ml/liter of drinking water) for four weeks. The gene expression of interferon-gamma (IFN-γ), interleukin (IL)-6, and IL-2 was determined at 3, 5 and 7 days post-infection (PI). Virus shedding titers and rates and haemagglutination inhibition (HI) antibody titers were detected. Clinical signs, mortalities and post-mortem lesions were recorded. The birds were weighed, and relative organ weights were calculated. Tissue specimens were taken for histopathological examination and immunohistochemistry (IHC). The expression of IFN-γ in the duodenum revealed a significant increase in G2 compared to G3 at 3 days PI, while the duodenal and splenic expression of IL-6 was significantly increased in G2 compared to G3 at 5 days PI. IL-2 was overexpressed in the duodenum in G3 compared to G2 at 3 and 5 days PI. A significant decrease (P ≤ 0.05) in the virus shedding titer and an increase in the HI titers were detected in G3 compared to G2. The clinical signs and the mortality rate were clearly appeared in G2 than in G3. By IHC, lower H9N2 staining intensity was observed in the examined organs from G3 than in those from G2. In conclusion, as a first report, vitamin E with Fetomune Plus® supplementation for four weeks could improve the immunological and pathological effects of H9N2 infection on chickens.


Assuntos
Suplementos Nutricionais , Influenza Aviária/terapia , Doenças das Aves Domésticas/terapia , Vitamina E/imunologia , Ração Animal , Animais , Anticorpos Antivirais/sangue , Galinhas , Citocinas/imunologia , Testes de Inibição da Hemaglutinação , Imuno-Histoquímica , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/imunologia , Interferon gama/imunologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Eliminação de Partículas Virais/efeitos dos fármacos , Vitamina E/administração & dosagem
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