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A Comparison of Toll-Like Receptor 5 and 21 Ligands as Adjuvants for a Formaldehyde Inactivated H9N2 Avian Influenza Virus Vaccine in Chickens.

Low pathogenic avian influenza virus (AIV) infection in chickens can result in economic losses and has impacts on human health. Poultry vaccination is a tool that can be used to decrease infection and transmission of AIVs. Prior research has demonstrated that Toll-like receptor (TLR) ligands can act as vaccine adjuvants and their addition to inactivated AIV vaccines can enhance immune responses elicited in chickens. The objective of this study was to compare the adjuvant capabilities of TLR5 ligand (flagellin) and TLR21 ligand (CpG ODN 2007) administered either alone or in combination with an …

Free-range chickens from Santa Catarina state, southern Brazil, as asymptomatic intermediate hosts for Toxoplasma gondii clonal type I and typical Brazilian genotypes.

Chickens are a host that is very resistant to the development of clinical toxoplasmosis. Free-range chickens have been used to indirectly track environmental contamination with Toxoplasma gondii oocysts because they feed on the ground. This study evaluated the genetic diversity of T. gondii isolates from free-range chickens from Florianópolis island in Santa Catarina state, southern Brazil. Sera from 21 chickens were tested for IgG anti-T. gondii antibodies using the modified agglutination test (MAT). Tissue homogenates from the 11 seropositive birds (MAT titres ≥5) were bioassayed in mice. Th…

Широкополосная защита бройлерных цыплят от гепатита тела путем иммунизации их родителей-производителей бройлера с помощью двувалентной вакцины от аденовируса птицы.

Исторически аденовирус птицы (FAdV), связанный с иммунодепрессией, считается вторичным заболеванием бройлерных цыплят. Однако ранее мы сообщали о том, что МБХ является одним из основных заболеваний в куриной промышленности в Канаде в результате инфекций различными серотипами FADV. Таким образом, цели этого исследования заключались в разработке стратегии иммунизации бройлеров с использованием живого FADV 11-1047 и FADV8a-TR59 для обеспечения гомологической и гетерологической защиты бройлерного потомства от ИБХ и в изучении эффективности естественного воздействия на наивного бройлера вируса живо

Совпадение в аннотации оригинала
Historically, fowl adenovirus (FAdV) associated inclusion body hepatitis (IBH) was considered a secondary disease in broiler chickens associated with immunosuppression. However, we previously reported the occurrence of IBH as a primary disease in the broiler chicken industry in Canada as a result of infections with various FAdV serotypes. Therefore, the obje…

Incorporation of membrane-anchored flagellin into Salmonella Gallinarum bacterial ghosts induces early immune responses and protection against fowl typhoid in young layer chickens.

The present study aimed to investigate whether the incorporation of flagellin, a TLR5 agonist, in the bacterial ghosts (BGs) of Salmonella Gallinarum can enhance protective immune responses against fowl typhoid, a septicemic disease of poultry, in chickens. BGs are empty cell envelopes derived from Gram-negative bacteria through the bacteriophage phiX174 gene E mediated lysis. In this study, the S. Gallinarum ghosts carrying flagellin were genetically constructed utilizing a lysis plasmid pJHL184-flagellin, designed for the coexpression of the flagellin and the lysis protein E. The adjuvant ef…

A novel hemagglutinin protein produced in bacteria protects chickens against H5N1 highly pathogenic avian influenza viruses by inducing H5 subtype-specific neutralizing antibodies.

The highly pathogenic (HP) H5N1 avian influenza viruses (AIVs) cause a mortality rate of up to 100% in infected chickens and pose a permanent pandemic threat. Attempts to obtain effective vaccines against H5N1 HPAIVs have focused on hemagglutinin (HA), an immunodominant viral antigen capable of eliciting neutralizing antibodies. The vast majority of vaccine projects have been performed using eukaryotic expression systems. In contrast, we used a bacterial expression system to produce vaccine HA protein (bacterial HA) according to our own design. The HA protein with the sequence of the H5N1 HPAI…

Evaluation of immune response in challenged chickens vaccinated with Newcastle disease vaccine using gums from Cedrela odorata and Khaya senegalensis as delivery agents.

Immune response of challenged chickens following previous vaccinations with Newcastle disease vaccine using gums from Cedrela odorata and Khaya senegalensis as delivery agent were evaluated. Two hundred and fifty-two one-day old chickens were divided into vaccine-gum oral (GVOR), vaccine-gum ocular (GVOC), vaccine oral (VOR), vaccine ocular (VOC), gum oral (GOR), gum ocular (GOC), No-gum-no-vaccine/challenged (NGNV/C), and No-gum-no-vaccine/unchallenged (NGNV/U) groups. They were vaccinated at days 21 & 42 and challenged at day 84. Trachea and intestinal washings were collected at intervals as…

Mutations in the haemagglutinin protein and their effect in transmission of highly pathogenic avian influenza (HPAI) H5N1 virus in sub-optimally vaccinated chickens.

BACKGROUND: Transmission of highly pathogenic avian influenza (HPAI) viruses in poultry flocks is associated with huge economic losses, cull … of our most antigenically-distant mutant may have in the transmission efficiency of this mutant to chickens vaccinated against the parent strain, under sub-optimal vaccination conditions resembling those often found in the field. METHODS: In this study we employed reverse genetics techniques and transmission experiments to examine if the HA mutations of …

Performance, histomorphology, and toll-like receptor, chemokine, and cytokine profile locally and systemically in broiler chickens fed diets supplemented with yeast-derived macromolecules.

The turnover of intestinal epithelial cells is a dynamic process that includes adequate cell proliferation and maturation in the presence of microbiota and migration and seeding of immune cells in early gut development in chickens. We studied the effect of yeast-derived macromolecules (YDM) on performance, gut health, and immune system gene expression in the intestine of broiler chickens. One thousand eighty 1-d-old birds, with 60 birds per pen and 6 pens per treatment, were randomly assigned to 3 treatment diets; a diet containing monensin (control), control diet supplemented with bacitracin …

Infection of chickens with antimicrobial-resistant Salmonella enterica Typhimurium DT193 and monophasic Salmonella Typhimurium-like variants: an emerging risk to the poultry industry?

Antimicrobial-resistant Salmonella enterica poses a particular risk to public health, and in particular isolates belonging to clonal lineage … lity of antimicrobial-resistant DT193 serotype 4,12:i:- and 4,5,12:i:- isolates from pigs to infect chickens. All isolates were found to colonize the caeca and liver. All but one isolate of serotype 4,5,12:i:- also infected the spleen. Levels of infection and pathology were comparable with those found with the virulent S. Typhimurium isolate 4/74. These fi …

Clostridium perfringens alpha-toxin and NetB toxin antibodies and their possible role in protection against necrotic enteritis and gangrenous dermatitis in broiler chickens.

Necrotic enteritis (NE) and gangrenous dermatitis (GD) are important infectious diseases of poultry. Although NE and GD share a common patho … d that the levels of antibodies against both toxins were significantly higher in apparently healthy chickens compared to birds with clinical signs of NE or GD, suggesting that these antitoxin antibodies may play a role in protection against NE and GD.

Time-course investigation of infection with a low virulent Pasteurella multocida strain in normal and immune-suppressed 12-week-old free-range chickens.

Twelve-week-old indigenous chickens, either immune-suppressed using dexamethasone (IS) or non-immune-suppressed (NIS), were challenged with a low virulent strain, Pasteurella multocida strain NCTC 10322(T), and developed clinical signs and pathological lesions typical of chronic fowl cholera. NIS birds demonstrated much more severe signs of fowl cholera than IS birds. With few exceptions, signs recorded in IS and NIS birds were of the same types, but significantly milder in the IS birds, indicating that immune suppression does not change the course of infection but rather the severity of signs…

Expression of avian beta-defensin 3, an antimicrobial peptide, by sperm in the male reproductive organs and oviduct in chickens: an immunohistochemical study.

The aim of this study was to determine whether chicken sperm express avian beta-defensin 3 (AvBD-3), an antimicrobial peptide, and retain it during the residence in the male and female reproductive tract. Immunocytochemistry to identify AvBD-3 was performed in the testis, epididymis, ductus deferens, ejaculated sperm, and utero-vaginal junction of the oviduct of inseminated hens. Reverse transcription-PCR analysis was also performed to confirm the synthesis of AvBD-3 by testicular cells and ejaculated sperm. The immunoreaction products for AvBD-3 were identified in the elongated spermatids att

Evaluation of an intestinal Lactobacillus reuteri strain expressing rumen fungal xylanase as a probiotic for broiler chickens fed on a wheat-based diet.

1. This study was conducted to evaluate the feasibility of using a transformed Lactobacillus reuteri Pg4 strain harbouring a rumen fungal xylanase gene as a probiotic supplement in a wheat-based poultry diet. 2. A total of 400 broiler chicks was allocated to two treatment groups with or without supplementation with 10(6) colony forming units (cfu)/g of transformed L. reuteri Pg4 in a wheat-based regimen to investigate the performance, intestinal microflora populations, digesta viscosity and excreta ammonia concentrations in these broiler chickens. 3. Supplementation of the wheat-based diet wit…

Effect of vitamin A and/or E on plasma enzymatic antioxidant systems and total antioxidant capacity of broiler chickens challenged with carbon tetrachloride.

This study was conducted to investigate the effect of vitamin A and E supplementation on the antioxidant defences of broiler chickens against carbon tetrachloride (CCl(4))-induced oxidative stress at 4 weeks of age. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities as well as total antioxidant (TAO) level were analysed before and after CCl(4) challenge. Day-old Lohman broiler chickens (n = 144) were randomly assigned to six factorially arranged dietary treatments consisting of vitamin A [1.35 (control) or +20 mg/kg] and vitamin E [20 (control), +40 or +60 mg/kg]. The backg…

Studies on production performance and toxin residues in tissues and eggs of layer chickens fed on diets with various concentrations of aflatoxin AFB1.

1. An experiment on 1-week-old, White Leghorn female chicks was conducted to study the effect of aflatoxin AFB1 on weight gain, feed intake, feed gain ratio, age at sexual maturity, production and quality of eggs, retention of nutrients, pathoanatomical and histopathological parameters, and also on AFB1 residues in eggs and muscles of hens. The chicks were assigned to 4 dietary treatments: D1 (without AFB1), D2 (2.50 mg/kg AFB1), D3 (3.13 mg/kg AFB1), D4 (3.91 mg/kg AFB1) up to the age of 40 weeks. 2. At the end of the experiment, the mean body weight gain and feed intake were significantly lo

Effects of orally administered tetracycline on the intestinal community structure of chickens and on tet determinant carriage by commensal bacteria and Campylobacter jejuni.

There is a growing concern that antibiotic usage in animal production has selected for resistant food-borne bacteria. Since tetracyclines ar … us spp., Escherichia coli, and Campylobacter spp. were isolated from the cecal droppings of broiler chickens. Enterococcus spp. and E. coli expressed tetracycline MICs of >8 microg/ml and harbored a variety of tet resistance determinants regardless of the tetracycline exposure history of the birds. The enterococcal isolates possessed tetM (61%), tetL (25.4 …

Major histocompatibility complex-linked immune response of young chickens vaccinated with an attenuated live infectious bursal disease virus vaccine followed by an infection.

The influence of the MHC on infectious bursal disease virus (IBDV) vaccine response in chickens was investigated in three different chicken lines containing four different MHC haplotypes. Two MHC haplotypes were present in all three lines with one haplotype (B19) shared between the lines. Line 1 further contains the BW1 haplotype isolated from a Red Jungle Fowl. Line 131 further contains the B131 haplotype isolated from a meat-type chicken. Finally, Line 21 further contains the international B21 haplotype. The chickens were vaccinated with live attenuated commercial IBDV vaccine at 3 wk of age…

Endothelial injury in internal organs of University of California at Davis line 200 (UCD 200) chickens, an animal model for systemic sclerosis (Scleroderma).

Systemic sclerosis (SSc) is a multisystem disorder characterized by mononuclear cell infiltration and fibrosis. Using skin samples from human SSc and UCD 200 chickens, which spontaneously develop a hereditary disease closely resembling human SSc, we have shown previously that endothelial cell apoptosis is a primary event in the pathogenesis of SSc. The aim of the present study was to investigate the initial disease stage in visceral organs of UCD 200 chickens with special emphasis on endothelial apoptosis, mononuclear cell infiltration and collagen deposition using tissue samples from oesophag…

Immune response and in vivo distribution of the virus in chickens inoculated with the cell-associated vaccine of attenuated infectious laryngotracheitis (ILT) virus.

Chickens inoculated with the cell-associated (CA) vaccine acquired higher protective immunity to ILT. In chickens vaccinated with CA or cell-free (CF) vaccine, respectively, virus-neutralizing and IgG- and IgM-ELISA antibodies were detected in the serum, but no antibody was detected in the tracheal washes of the vaccinated chickens. More apparent antibody response was seen in chickens vaccinated with the CA vaccine than with the CF vaccine. The antibody titers did not correlate closely with the protection against challenge with ILT virus. After subcutaneous injection of either CA or CF vaccine…