scholarly journals The influence of age on the response of SPF hens to infection with Salmonella enteritidis PT4

1991 ◽  
Vol 106 (1) ◽  
pp. 33-43 ◽  
Author(s):  
T. J. Humphrey ◽  
H. Chart ◽  
A. Baskerville ◽  
B. Rowe
Keyword(s):  
Antibody Response ◽  
Salmonella Enteritidis ◽  
Specific Pathogen Free ◽  
Salmonella Infections ◽  
Specific Pathogen ◽  
Direct Administration

SUMMARYWhen Specific Pathogen–Free hens were infected with Salmonella enteritidis PT4 by direct administration into the crop, the age of the bird at infection was found to have an effect on both pathogenesis and antibody response. Birds at 20 weeks of age showed no adverse signs and developed high titres of antibodies of the IgM class, while those which were 1 year old at infection developed relatively little antibody arid had acute septicaemia, with 6 of 10 birds either dying or having to be humanely destroyed. The implication of these results for the control of salmonella infections in poultry is discussed.

scholarly journals GapA+ Mycoplasma gallisepticum ts-11 has improved vaccine characteristics

Microbiology ◽  
2011 ◽  
Vol 157 (6) ◽  
pp. 1740-1749 ◽  
Author(s):  
Pollob K. Shil ◽  
Anna Kanci ◽  
Glenn F. Browning ◽  
Marc S. Marenda ◽  
Amir H. Noormohammadi ◽  
...  
Keyword(s):  
Antibody Response ◽  
Respiratory Disease ◽  
Vaccine Candidate ◽  
Clinical Signs ◽  
Mycoplasma Gallisepticum ◽  
Specific Pathogen Free ◽  
Live Attenuated Vaccine ◽  
Live Attenuated Vaccines ◽  
Specific Pathogen ◽  
Dose Dependent

Mycoplasma gallisepticum (MG) is an important poultry pathogen that causes respiratory disease and loss of production worldwide, and is currently controlled with live attenuated vaccines. These vaccines have limitations as they vary in their pathogenicity, the protection afforded and their transmissibility, but have been shown to effectively reduce losses associated with challenge in the field. A live attenuated vaccine, ts-11, has been used for the control of M. gallisepticum in several countries. This vaccine is highly dose-dependent and the flock antibody response is weak. GapA is the primary cytadherence molecule in M. gallisepticum, and the absence of GapA expression has been observed in the vast majority of cells in the ts-11 vaccine strain. In this study the immunogenicity of a GapA+ M. gallisepticum ts-11 vaccine was investigated in specific-pathogen-free chickens. Birds vaccinated with GapA+ M. gallisepticum ts-11 were protected against clinical signs of disease following challenge with virulent M. gallisepticum, and GapA+ M. gallisepticum ts-11 was shown to be non-pathogenic and more immunogenic at a lower dose than the currently available M. gallisepticum ts-11 vaccine. Thus, GapA+ M. gallisepticum ts-11 appears to have improved potential as a vaccine candidate.

scholarly journals Effect of Antibiotics on the Colonization of Live Attenuated Salmonella Enteritidis Vaccine in Chickens

2021 ◽  
Vol 8 ◽  
Author(s):  
Jiangang Hu ◽  
Chuanyan Che ◽  
Jiakun Zuo ◽  
Xiangpeng Niu ◽  
Zhihao Wang ◽  
...  
Keyword(s):  
Vaccine Strain ◽  
Salmonella Enteritidis ◽  
Antibiotic Use ◽  
Live Vaccine ◽  
Live Vaccine Strain ◽  
Specific Pathogen Free ◽  
Live Vaccines ◽  
The World ◽  
Specific Pathogen ◽  
Effective Use

Salmonellosis, caused by Salmonella Enteritidis, is a prevalent zoonosis that has serious consequences for human health and the development of the poultry sector. The Salmonella Enteritis live vaccine (Sm24/Rif12/Ssq strain) is used to prevent Salmonella Enteritidis around the world. However, in some parts of the world, poultry flocks are frequently raised under intensive conditions, with significant amounts of antimicrobials to prevent and treat disease and to promote growth. To investigate whether antibiotic use influences the colonization of orally administered Salmonella live vaccines, 240 1-day-old specific pathogen-free chicks were randomly divided into 24 groups of 10 animals for this study. The different groups were treated with different antibiotics, which included ceftiofur, amoxicillin, enrofloxacin, and lincomycin–spectinomycin. Each group was immunized 2, 3, 4, and 5 days after withdrawal, respectively. At 5 days after immunization, the blood, liver, and ceca with contents were collected for the isolation of the Salmonella live vaccine strain. The result showed that no Salmonella vaccine strain was isolated in the blood and liver of the chicks in those groups. The highest number of Salmonella vaccine strains was isolated in the cecum from chicks vaccinated 2 days after ceftiofur withdrawal, and no Salmonella vaccine strain was isolated from the cecum in chicks immunized 3 days after ceftiofur withdrawal. Among the chickens immunized 4 days after the withdrawal of amoxicillin, enrofloxacin, and lincomycin–spectinomycin, the number of Salmonella vaccine colonization in the cecum was the highest, which was higher than that of the chickens immunized at other withdrawal interval (2, 3, and 5 days) groups and was higher than that of the chickens without treatment (P < 0.05). This study provides a reference for the effective use of the Salmonella Enteritidis live vaccine and key antibiotics commonly utilized in the poultry industry.

Effects of Gamma Irradiation on the Viability and Phenotypic Characteristics of Salmonella Enteritidis Inoculated into Specific-Pathogen-Free Eggs

2011 ◽  
Vol 74 (12) ◽  
pp. 2031-2038 ◽  
Author(s):  
ELIZABETH C. P. RODRIGUES ◽  
MAURO C. L. SOUZA ◽  
SANDRO S. TOLEDO ◽  
CELSO G. BARBOSA ◽  
ELIANE M. F. REIS ◽  
...  
Keyword(s):  
Gamma Irradiation ◽  
Salmonella Enteritidis ◽  
Egg Yolk ◽  
Specific Pathogen Free ◽  
Bacterial Strains ◽  
Phenotypic Characteristics ◽  
Shell Eggs ◽  
Lactose Fermentation ◽  
Specific Pathogen ◽  
60Co Radiation

The goal of this study was to determine the effects of various levels of gamma irradiation on the phenotypic characteristics of 20 strains of Salmonella Enteritidis inoculated separately into specific-pathogen-free shell eggs. Bacterial strains were inoculated into egg yolks and exposed to 60Co radiation at doses of 0.49 to 5.0 kGy. The eggs were maintained at 25°C and analyzed for the presence of Salmonella on days 1, 2, 4, and 7, and the recovered Salmonella isolates were characterized biochemically. All strains were resistant to doses of 0.49, 0.54, 0.59, 0.8, and 1 kGy; colony counts were ≥105 CFU/ml of egg yolk except for one strain, which was detected at 96 h and at 7 days after irradiation at 1 kGy, with a population reduction of 2 log CFU/ml. For the other evaluated doses, 12 strains (60.0%) were resistant at 1.5 kGy and 7 strains (35.0%) were resistant at 3.0 kGy. Among all analyzed strains, 5.0 kGy was more effective for reducing and/or eliminating the inoculated bacteria; only two (10%) strains were resistant to this level of irradiation. Salmonella colony counts were significantly reduced (P < 0.01) with increasing doses from the day 1 to 7 of observation, when microbial growth peaked. Loss of mobility, lactose fermentation, citrate utilization, and hydrogen sulfide production occurred in some strains after irradiation independent of dose and postirradiation storage time. Increases in antibiotic susceptibility also occurred: seven strains became sensitive to β-lactams, two strains became sensitive to antifolates, and one strain each became sensitive to fluoroquinolone, phenicol, nitrofurans, tetracyclines, and aminoglycosides. The results indicate that up to 5.0 kGy of radiation applied to shell eggs inoculated with Salmonella Enteritidis at 4 log CFU per egg is not sufficient for complete elimination of this pathogen from this food matrix.

scholarly journals Antibacterial activity of chitosan biofilm for the conservation of fertile and table eggs

2020 ◽  
Vol 72 (1) ◽  
pp. 208-214
Author(s):  
R.O.F. Prado ◽  
I.G. Tellez ◽  
M.L.J. García ◽  
L.L.E. Aldaco ◽  
C.A.C. García
Keyword(s):  
Antibacterial Activity ◽  
Salmonella Enteritidis ◽  
Physiological Saline ◽  
Chitosan Solution ◽  
Specific Pathogen Free ◽  
Egg Weight ◽  
Randomized Design ◽  
Physiological Saline Solution ◽  
Specific Pathogen ◽  
Practical Tool

ABSTRACT The aim of this study was to develop a chitosan biofilm against Salmonella enteritidis, for the conservation of fertile and table eggs. Two experiments were performed. Experiment 1: 400 specific pathogen-free table eggs were divided in a completely randomized design into four treatments, five replicates and each replicate with 20 table eggs. Experimental groups were assigned to control and 1, 5 and 10% chitosan treatment. The eggs were immersed in the chitosan solution. They were then exposed to Salmonella enteritidis and stored for 1, 24, 96 and 168h at 4ºC. The eggs were then washed with 10mL of physiological saline solution. Experiment 2: 80 specific pathogen-free fertile eggs were tested, the assays were assigned to control and 1, 5 and 10% chitosan treatment. Each treatment had 20 fertile eggs. The eggs were immersed in the chitosan solution. They were individually weighed and incubated. Egg weight, humidity loss, and hatchability (weight and length of newly hatched chicks) characteristics were assessed. In Experiment 1, comparison between treatments showed differences (P< 0.05) in the total recovered of Salmonella enteritidis on eggshell, with the lower values in 5 y 10% chitosan treatment at 96 y 168h respectively. In Experiment 2, chitosan did not show any effect on the egg weight and chick weight, where the average was 57.44 and 38.23g respectively. The humidity loss and chick length showed differences (P< 0.05), with the lower values in 5 y 10% chitosan treatment. The antibacterial activity of chitosan biofilm provide a practical tool against Salmonella enteritidis in fertile and table eggs because the chitosan did not affect egg weight and chick weight, relevant parameters in the poultry industry.

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