Frequency and Magnitude of Internal Organ Colonization Following Exposure of Laying Hens to Different Oral Doses of Salmonella enteritidis

2011 ◽  
Vol 10 (4) ◽  
pp. 325-331 ◽  
Author(s):  
Richard K. Gast ◽  
Rupa Guraya ◽  
Jean Guard ◽  
Peter S. Holt
2013 ◽  
Vol 76 (1) ◽  
pp. 108-113 ◽  
Author(s):  
RICHARD K. GAST ◽  
RUPA GURAYA ◽  
JEAN GUARD

The continuing attribution of human Salmonella Enteritidis infections to internally contaminated eggs has necessitated the commitment of substantial public and private resources to Salmonella Enteritidis testing and control programs in commercial laying flocks. Cost-effective risk-reduction requires a detailed and comprehensive understanding of how Salmonella Enteritidis infections in hens result in deposition of the pathogen inside eggs. The present study sought to resolve some incompletely defined aspects of the relationship between Salmonella Enteritidis oral-exposure dose levels in experimentally infected laying hens and the frequency and location of subsequent egg contamination. In two trials, groups of specific-pathogen-free hens were experimentally inoculated with oral doses of 104, 106, or 108 CFU of a phage type 4 Salmonella Enteritidis strain. Eggs were collected 5 to 23 days postinoculation, and the yolk and albumen of each egg were cultured separately to detect Salmonella Enteritidis contamination. Larger oral doses of Salmonella Enteritidis administered to hens were associated with significant increases in the frequencies of both yolk and albumen contamination. Moreover, Salmonella Enteritidis was found in the albumen of a far-higher proportion of contaminated eggs from hens given the largest dose than from the other two groups. Salmonella Enteritidis contamination was detected in 0.7% of yolk and 0.2% of albumen samples after inoculation of hens with 104 CFU, 4.0% of yolk and 1.7% of albumen samples after inoculation with 106 CFU, and 6.5% of yolk and 10.8% of albumen samples after inoculation with 108 CFU. These results demonstrate that oral-exposure doses of Salmonella Enteritidis for laying hens can significantly affect both the frequency and location of deposition of this pathogen inside eggs.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 360
Author(s):  
Georgi Yu. Laptev ◽  
Elena A. Yildirim ◽  
Larisa A. Ilina ◽  
Valentina A. Filippova ◽  
Ivan I. Kochish ◽  
...  

One of the main roles in poultry resistance to infections caused by Salmonella is attributed to host immunity and intestinal microbiota. We conducted an experiment that involved challenging Lohmann White laying hens with Salmonella Enteritidis (SE), feeding them a diet supplemented with an EOs-based phytobiotic Intebio®. At 1 and 7 days post-inoculation, the expression profiles of eight genes related to immunity, transport of nutrients in the intestine, and metabolism were examined. Cecal microbiome composition and blood biochemical/immunological indices were also explored and egg production traits recorded. As a result, the SE challenge of laying hens and Intebio® administration had either a suppressive or activating effect on the expression level of the studied genes (e.g., IL6 and BPIFB3), the latter echoing mammalian/human tissue-specific expression. There were also effects of the pathogen challenge and phytobiotic intake on the cecal microbiome profiles and blood biochemical/immunological parameters, including those reflecting the activity of the birds’ immune systems (e.g., serum bactericidal activity, β-lysine content, and immunoglobulin levels). Significant differences between control and experimental subgroups in egg performance traits (i.e., egg weight/number/mass) were also found. The phytobiotic administration suggested a positive effect on the welfare and productivity of poultry.


1994 ◽  
Vol 38 (2) ◽  
pp. 282 ◽  
Author(s):  
Masayuki Nakamura ◽  
Noriyuki Nagamine ◽  
Toshio Takahashi ◽  
Shoko Suzuki ◽  
Mayumi Kijima ◽  
...  

2017 ◽  
Vol 26 (2) ◽  
pp. 286-294
Author(s):  
P. Adhikari ◽  
D.E. Cosby ◽  
N.A. Cox ◽  
W.K. Kim

Sign in / Sign up

Export Citation Format

Share Document