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The Journal of Veterinary Medical... Jun 2000The relationship between release properties of the model antigen, bovine serum albumin (BSA), from formulations in vitro and immune response after administration of...
The relationship between release properties of the model antigen, bovine serum albumin (BSA), from formulations in vitro and immune response after administration of various oil adjuvanted vaccines containing liquid paraffin was examined in chickens. The vaccine prepared at an hydrophile-lipophile-balance (HLB) number of 4.8 showed slower release of BSA and higher immune response on injected chickens than that with an HLB number of 6.0. Decreases of aqueous volume ratio in the formulation also led to slower release of BSA and higher immune response. The slower release rate of BSA showed higher ELISA antibody titer even at 20 weeks after vaccination. The ELISA antibody titer inversely was related to the constant release rate, k, calculated from the in vitro release test. The correlation coefficient was 0.863. The immune response of oil adjuvanted vaccines containing Haemophilus paragallinarum agreed well with these results with BSA. Our results indicated that a stronger and more prolonged immune response of oil adjuvanted vaccines was achieved by slower release rate of antigen from the formulation. In addition, there was a good correlation between immune response and the value of k.
Topics: Adjuvants, Immunologic; Animals; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Vaccines; Biological Assay; Chickens; Delayed-Action Preparations; Enzyme-Linked Immunosorbent Assay; Haemophilus; Haemophilus Infections; Hemagglutination Inhibition Tests; Hexoses; Paraffin; Polysorbates; Poultry Diseases; Serum Albumin, Bovine; Specific Pathogen-Free Organisms; Surface Properties; Surface-Active Agents; Vaccination
PubMed: 10907681
DOI: 10.1292/jvms.62.571 -
Veterinary Research Sep 2020Infectious coryza (IC), an upper respiratory tract disease affecting chickens, is caused by Avibacterium paragallinarum. The clinical manifestations of IC include nasal...
Infectious coryza (IC), an upper respiratory tract disease affecting chickens, is caused by Avibacterium paragallinarum. The clinical manifestations of IC include nasal discharge, facial swelling, and lacrimation. This acute disease results in high morbidity and low mortality, while the course of the disease is prolonged and mortality rates are increased in cases with secondary infections. Studies regarding the immune response in infected chickens are scarce, and the local immune response is the focal point of investigation. However, a large body of work has demonstrated that severe infections can impact the systemic immune response. The objective of this study was to evaluate the systemic effects of Avibacterium paragallinarum (serovar B-1) infection on immune cells in specific pathogen-free (SPF) chickens. The current study revealed the presence of a transient circulating monocyte population endowed with high phagocytic ability and clear downregulation of major histocompatibility complex class II (MHC-II) surface expression. In human and mouse studies, this monocyte population (identified as tolerant monocytes) has been correlated with a dysfunctional immune response, increasing the risk of secondary infections and mortality. Consistent with this dysfunctional immune response, we demonstrate that B cells from infected chickens produced fewer antibodies than those from control chickens. Moreover, T cells isolated from the peripheral blood of infected chickens had a lower ability to proliferate in response to concanavalin A than those isolated from control chickens. These findings could be related to the severe clinical signs observed in complicated IC caused by the presence of secondary infections.
Topics: Animals; Chickens; Haemophilus Infections; Haemophilus paragallinarum; Histocompatibility Antigens Class II; Monocytes; Poultry Diseases; Specific Pathogen-Free Organisms
PubMed: 32977847
DOI: 10.1186/s13567-020-00840-7 -
Poultry Science Apr 2018This paper reports on the development and validation of a real-time loop-mediated isothermal amplification assay (LAMP) for rapid and specific identification of...
This paper reports on the development and validation of a real-time loop-mediated isothermal amplification assay (LAMP) for rapid and specific identification of Gallibacterium anatis. To design a set of 6 primers using the LAMP technique, the conserved region of the G. anatis sodA gene was selected as a target. To evaluate primer specificity we used 120 field strains, the reference strain G. anatis ATCC 43329, and 9 non-G. anatis bacteria. The results confirmed positive reactions for all G. anatis strains tested by LAMP at 63°C for 60 min, with no cross-reactivity observed for the negative control bacteria, i.e., Haemophilus parainfluenzae (ATCC 51505 and ATCC 33392), Aggregatibacter aphrophilus ATCC 7901, Avibacterium endocarditis, Pasteurella multocida, Actinobacillus pleuropneumoniae, Avibacterium paragallinarum, Ornithobacterium rhinotracheale, and Escherichia coli. The lowest detectable amount of DNA for the LAMP reaction was 0.2561 pg, which was detected in about 34 min, while the highest available concentration of the G. anatis reference strain was detected in about 10 min. The lowest detectable amount of DNA for the real-time PCR reaction was 21.24 pg, which was detected in about 20 min, while the highest available concentration of the G. anatis reference strain was detected in about 7 min. Moreover, using the real-time LAMP assay the reaction could be effectively carried out in a volume of just 13 μL, about half the officially recommended reaction volume (25 μL). The aim of this study was to develop a highly sensitive and specific G. anatis real-time LAMP assay that is less time-consuming and less costly than quantitative PCR.
Topics: Animals; Bacterial Proteins; Chickens; Female; Nucleic Acid Amplification Techniques; Pasteurellaceae; Pasteurellaceae Infections; Poultry Diseases; Superoxide Dismutase; Turkeys
PubMed: 29381805
DOI: 10.3382/ps/pex420 -
Canadian Journal of Veterinary Research... Apr 2008Tonsillar and nasal swabs were collected from weanling pigs in 50 representative Ontario swine herds and tested for the presence of 5 important bacterial upper...
Prevalence of Actinobacillus pleuropneumoniae, Actinobacillus suis, Haemophilus parasuis, Pasteurella multocida, and Streptococcus suis in representative Ontario swine herds.
Tonsillar and nasal swabs were collected from weanling pigs in 50 representative Ontario swine herds and tested for the presence of 5 important bacterial upper respiratory tract pathogens. All but 1 herd (2%) tested positive for Streptococcus suis by polymerase chain reaction (PCR); 48% of herds were S. suis serovar 2, 1/2 positive. In all but 2 herds there was evidence of Haemophilus parasuis infection. In contrast, toxigenic strains of Pasteurella multocida were detected by a P. multocida--enzyme-linked immunosorbant assay (PMT-ELISA) in only one herd. Seventy-eight percent of the herds were diagnosed positive for Actinobacillus pleuropneumoniae by apxIV PCR. Sera from finishing pigs on the same farms were also collected and tested by ELISA for the presence of A. pleuropneumoniae antibodies. Seventy percent of the herds tested had evidence of antibodies to A. pleuropneumoniae including serovars 1-9-11 (2%), 2 (4%), 3-6-8-15 (15%), 5 (6%), 4-7 (26%), and 12 (17%). This likely represents a shift from previous years when infection with A. pleuropneumoniae serovars 1, 5, and 7 predominated. At least 16% and possibly as many as 94% of the herds tested were Actinobacillus suis positive; only 3 of the 50 herds were both A. pleuropneumoniae and A. suis negative as judged by the absence of a positive PCR test for apxII. Taken together, these data suggest that over the past 10 years, there has been a shift in the presence of pathogenic bacteria carried by healthy Ontario swine with the virtual elimination of toxigenic strains of P. multocida and a move to less virulent A. pleuropneumoniae serovars. As well, there appears to be an increase in prevalence of S. suis serovar 2, 1/2, but this may be a reflection of the use of a more sensitive detection method.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Actinobacillus suis; Animals; Antibodies, Bacterial; Enzyme-Linked Immunosorbent Assay; Female; Haemophilus Infections; Haemophilus paragallinarum; Male; Nasal Cavity; Ontario; Palatine Tonsil; Pasteurella Infections; Pasteurella multocida; Polymerase Chain Reaction; Prevalence; Sensitivity and Specificity; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases
PubMed: 18505187
DOI: No ID Found -
Research in Microbiology Jun 2009Avian haemophili demonstrating in vitro satellitic growth, also referred to as the V-factor or NAD requirement, have mainly been classified with Avibacterium... (Comparative Study)
Comparative Study
Avian haemophili demonstrating in vitro satellitic growth, also referred to as the V-factor or NAD requirement, have mainly been classified with Avibacterium paragallinarum (Haemophilus paragallinarum), Avibacterium avium (Pasteurella avium), Avibacterium volantium (Pasteurella volantium) and Avibacterium sp. A (Pasteurella species A). The aim of the present study was to assess the taxonomic position of 18 V-factor-requiring isolates of unclassified Haemophilus-like organisms isolated from galliforme, anseriforme, columbiforme and gruiforme birds as well as kestrels and psittacine birds including budgerigars by conventional phenotypic tests and 16S rRNA gene sequencing. All isolates shared phenotypical characteristics which allowed classification with Pasteurellaceae. Haemolysis of bovine red blood cells was negative. Haemin (X-factor) was not required for growth. Maximum-likelihood phylogenetic analysis including bootstrap analysis showed that six isolates were related to the avian 16S rRNA group and were classified as Avibacterium according to 16S rRNA sequence analysis. Surprisingly, the other 12 isolates were unrelated to Avibacterium. Two isolates were unrelated to any of the known 16S rRNA groups of Pasteurellaceae. Two isolates were related to Volucribacter of the avian 16S rRNA group. Seven isolates belonged to the Testudinis 16S rRNA group and out of these, two isolates were closely related to taxa 14 and 32 of Bisgaard, whereas four other isolates were found to form a genus-like group distantly related to taxon 40 and one isolate remained distantly related to other members of the Testudinis group. One isolate was closely related to taxon 26 (a member of Actinobacillus sensu stricto). The study documented major genetic diversity among V-factor-requiring avian isolates beyond the traditional interpretation that they only belong to Avibacterium, underlining the limited value of satellitic growth for identification of avian members of Pasteurellaceae. Our study also emphasized that these organisms will never be isolated without the use of special media satisfying the V-factor requirement.
Topics: Animals; Birds; DNA, Bacterial; DNA, Ribosomal; Molecular Sequence Data; Pasteurellaceae; Phylogeny; RNA, Ribosomal, 16S; Sequence Alignment; Sequence Analysis, DNA
PubMed: 19573597
DOI: 10.1016/j.resmic.2009.05.006