An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
... 1. Systemic and intestinal antibody titres were measured in chickens following subcutaneous, intraperitoneal (IP), oral (po) and combined IP/po administration of antigen, in soluble, emulsified or microparticulate form. Antigens tested included keyhole limpet haemocyanin (KLH), killed Campylobacter jejuni whole cells and purified campylobacter flagellin protein. 2. The effect of immunisation with ...
... A fusion protein which comprises the B subunit of the labile toxin (LT-B) of E. coli and part of the flagellin (flaA) protein of C. jejuni is antigenic and is useful for decreasing colonization in chickens by Campylobacter species. The protein is produced by E. coli cells, transformed by the plasmid pBEB into which DNA sequences encoding the novel protein have been introduced. ...
... An enzyme-linked immunosorbent sandwich assay (ELISA) has been developed to detect and quantify both the K88+ fimbrial antigen and the concentration of bacterial cells in fecal and other samples using anti-fimbrial chicken egg-yolk and anti-fimbrial rabbit serum antibodies. The assay has a sensitivity of 40 ng ml(-1) for K88+ fimbrial antigen and 10(7) CFU ml(-1) for intact cells and cell homogena ...
... Chicken egg yolk antibody (IgY) raised against Salmonella enteritidis or Salmonella typhimurium was found in highly specific activity levels by ELISA. S. enteritidis- and S. typhimurium-specific IgY powder, prepared by freeze-drying the egg yolk water-soluble fraction, contained 15.5 and 10.0% of specific IgY, respectively. Anti-S. enteritidis IgY cross-reacted 55.3% with S. typhimurium. The cross ...
... A new type of adjuvant was tested for its ability to initiate antibody production in chickens, and its cellular and tissue compatibility were assessed. The stable biocompatible adjuvants tested are based on surface-modified solid lipid nanoparticles (SLNs), made from paraffin or biodegradable glyc-erides, and are simply admixed to the antigens before administration. The tissue-damaging potency of ...
... Lymphocyte proliferation and interleukin (IL)-2 and IL-6 levels in serum were measured as indicators of cell-mediated immunity after immunization of chickens with a commercial killed Salmonella enteritidis (SE) vaccine or experimental subunit vaccines of crude protein (CP) extract or the outer membrane protein (OMP). Significantly increased proliferative responses to SE flagella, but not lipopolys ...
... Two experimental approaches were used to investigate the immunological responses of chickens to a commercial killed Salmonella enteritidis (SE) vaccine. In the first, the effects of host age on antigen-specific proliferative responses and cytokine production were examined. Compared with non-vaccinated controls, 4-wk-old vaccinated chickens showed higher proliferation to SE LPS and flagella. The ly ...
... Intensive effort has been invested in the search for new effective vaccines that can be conveniently administered, with minimal handling of birds. Heat-labile enterotoxin (LT) of Escherichia coli H10407 is known as a powerful adjuvant for injection and oral administration. However, to use the toxin as an immunostimulator in animals, its toxicity must be neutralized. To this aim, we modified the LT ...
... Colibacillosis accounts for significant losses to the poultry industry, and control efforts are hampered by limited understanding of the mechanisms used by avian pathogenic Escherichia coli (APEC) to cause disease. We have found that the presence of the increased serum survival gene (iss) is strongly associated with APEC but not with commensal E. coli, making iss, and the protein it encodes (Iss), ...
... Toll-like receptors (TLRs) play a major role in the innate immune system for initial recognition of microbial pathogens and pathogen associated components. Nitric oxide (NO) is generated in immune cells in response to microbial stimulation and is involved in pathogenesis and control of infection. We used RT-PCR analysis to examine the TLR expression profile on chicken monocytes and demonstrated th ...
... Inactivated vaccines of Avibacterium paragallinarum provide protection and reduce the economic losses caused by infectious coryza. However, inactivated bacterins provide protection only against the Page serovars included in the vaccine. In this study, we investigated the immunological properties of a functional recombinant haemagglutinin protein (rHagA) derived from a Taiwan isolate strain A9 as t ...
... Mycoplasma synoviae is a major pathogen of chickens and turkeys, causing respiratory disease and infectious synovitis. M. synoviae haemagglutinin VlhA is an abundant surface-exposed lipoprotein and immunodominant antigen. Post-translational cleavage of VlhA generates two proteins, MSPB and MSPA. MSPB, the amino-terminal end of VlhA, is a lipoprotein of about 40-50 kDa but can appear in truncated f ...
... Groups of eight chickens were challenged with 10-fold dilutions of one of two strains of Mycoplasma synoviae (MS); each challenge group contained two noninfected sentinels. Both strains were highly efficient in colonizing the respiratory tract with challenge doses as low as 76 and 24 color-changing units/bird. Infection spread rapidly (within 7 days) to sentinels, while uninfected control chickens ...
... The objectives of this study were to identify haemagglutinin (HA) epitopes of Avibacterium paragallinarum serovar C that are capable of eliciting haemagglutination inhibition (HI) antibody, and to investigate their immunogenic role. Three conformational epitopes were detected on HA by blocking ELISA and immuno-dot blot analysis using a panel of five monoclonal antibodies (MAbs) with HI activity, d ...
... IgY is a chicken egg yolk antibody which has been used for treatment and prophylaxis of gastrointestinal infections. Our aim was to verify if IgY obtained from chickens immunized with EPEC O111, STEC O111 and STEC O157 is able to show in vitro reactivity and biological activity towards the three bacteria. IgY was obtained from eggs laid before and after immunization with each bacterium. The prepar ...
... In iron-limiting environments, Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Typhimurium synthesize and secrete several types of siderophore to trap trivalent ferric ions; these bacteria then express siderophore receptors called iron-regulated outer membrane proteins (IROMPs). In this study, we experimentally reproduced iron-limiting environments using a divalent metal ch ...
... FliC, the flagellin antigen of Salmonella Enteritidis, was tested as a vaccine candidate for protective effect against a homologous challenge in chickens. After immunization with recombinant FliC (rFliC) or administration of phosphate-buffered saline (PBS) at 56 days old, the chickens were challenged with 10⁹ colony-forming units of Salmonella Enteritidis at 76 days old. The vaccinated birds showe ...