A5001534741- Salmonella and Campylobacter epidemiology
- Viral gastroenteritis research and epidemiology
- Animal Nutrition and Physiology
- Listeria monocytogenes in Food Safety
- Bacteriophages and microbial interactions
- Animal Virus Infections Studies
- Food Safety and Hygiene
- Livestock and Poultry Management
- SARS-CoV-2 detection and testing
- Antibiotic Resistance in Bacteria
- Biosensors and Analytical Detection
- Insect and Pesticide Research
- Escherichia coli research studies
- Fecal contamination and water quality
- Insects and Parasite Interactions
- Indoor Air Quality and Microbial Exposure
- Pharmaceutical and Antibiotic Environmental Impacts
- Vibrio bacteria research studies
- Genomics and Phylogenetic Studies
- Animal Behavior and Welfare Studies
- Trace Elements in Health
- Meat and Animal Product Quality
- Identification and Quantification in Food
- Probiotics and Fermented Foods
- Aquaculture disease management and microbiota
Agricultural Research Service
2015-2024
U.S. National Poultry Research Center
2014-2024
Quality Research
2010-2022
United States Department of Agriculture
2008-2021
Georgia Department of Agriculture
2011
The Ohio State University
1985-1988
Laying hens of three different ages were experimentally infected with a strain Salmonella enteritidis by either oral inoculation or contact transmission. Total egg production was depressed in exposed all age groups. Persistent intestinal shedding observed small number hens. Eggs contents contaminated S. produced at high frequency, but only during fairly short period time that extended through approximately 1 week postinoculation for older and 2 weeks younger recovered from whole yolks...
A move from conventional cages to either an enriched cage or a noncage system may affect the safety quality, both, of eggs laid by hens raised in this new environment. The be altered microbiologically through contamination internal contents with Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) other pathogens, chemically due dioxins, pesticides, heavy metals. Quality affected changes integrity shell, yolk, albumen along function, composition, nutrition. Season, hen breed,...
Tissues from experimentally infected hens were examined for the presence of Salmonella enteritidis (SE). SE was recovered internal organs both orally inoculated and by horizontal contact transmission. isolated 58% ceca, 51% livers, 47% spleens, 17% ovaries, oviducts sampled during first 5 weeks after exposure. at a low frequency all as long 22
Two replicate experiments were conducted to test the efficacy of two different Salmonella enteritidis oil-emulsion bacterins (an experimentally prepared acetone-killed vaccine and a commercially available vaccine) for protecting laying hens against intestinal colonization following oral exposure S. enteritidis. Each was administered twice (4 weeks apart), all challenged with 10(8) cells nalidixic-acid-resistant strain 2 after second vaccination. Fecal samples from vaccinated unvaccinated...
Houseflies (Musca domestica) released into rooms containing hens challenged with Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) rapidly became contaminated Enteritidis. Forty to 50% of the flies were at 48 h, and percentage increased 50 70% 4 7 days postexposure then decreased 30% day 15. Initial attempts recovering surface organisms for culture using an aqueous rinse largely unsuccessful, while cultures internal contents readily recovered However, when 0.5% detergent was...
Salmonella Enteritidis in contaminated eggs is a public health hazard that may cause hospitalization or death the elderly, infants, and individuals with impaired immune systems. Prevention of infection laying hens an essential first step reducing outbreaks humans. Multiple interventions at several stages during egg production can combine to reduce numbers infected chickens keep contamination low levels. Every effort should be made exclude from premises by implementing effective biosecurity...
Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of safety, but comprehensive assessment hen systems in the US has not been conducted. The current study is part holistic, multidisciplinary comparison diverse conventional cage, enriched colony cage-free aviary focuses on environmental microbiology. Environmental swabs eggshell pools were collected from all during 4 periods. Total aerobes coliforms...
Prompt refrigeration to temperatures capable of restricting microbial growth has been recommended as an approach reducing the likelihood that contaminated eggs will transmit Salmonella enteritidis humans. By using experimentally egg components, present study determined extent which small numbers S. could grow more dangerous levels at different over a period up 3 d. This model was intended simulate potential opportunities for multiplication following oviposition and prior achievement internal...
In each of two replicate trials, 1-d-old chicks were inoculated orally with a phage type 13 Salmonella enteritidis isolate (resistant to nalidixic acid). Although S. was found in the livers, spleens, and ceca all sampled at 1 wk postinoculation, colonization generally persisted beyond 4 postinoculation only ceca. Nearly half remaining hens still shedding their feces 24 age, but 62 laid eggs that internally contaminated during initial 6 egg production. Chickens exposed shortly after hatching...
Because egg yolk and albumen differ substantially in their abilities to support bacterial growth, the initial level location of Salmonella enteritidis deposition are critical for determining whether proposed standards refrigerating eggs likely protect public health by preventing extensive microbial multiplication. In present study, three groups laying hens were infected with oral doses approximately 10(9) cells different S. strains (two phage type 4 one was 13a) two replicate trials. For all...
Internal contamination of eggs laid by hens infected with Salmonella enteritidis has been a prominent international public health issue since the mid-1980s. Considerable resources have committed to detecting and controlling S. infections in commercial laying flocks. Recently, Centers for Disease Control Prevention also reported significant association between or egg-containing foods heidelberg humans. The present study sought determine whether several isolates obtained from egg-associated...
To assess the potential protective efficacy of a Salmonella enteritidis bacterin, an acetone-killed oil-emulsion vaccine was prepared from phage type 13a S. strain and administered subcutaneously to hens in two experiments. Hens were housed individually, every other hen vaccinated (at 23 weeks age one experiment at 45 other). A second (booster) bacterin injection 6 later both Three after vaccination, all challenged with oral dose approximately 10(9) cells heterologous (phage 14b) strain. In...
Salmonella enteritidis is currently thought to be transmitted principally through contact with infected individuals and ingestion of fecally contaminated materials. The present study was undertaken determine if S. could spread in chickens by the airborne route induced molting affect this mode transmission. To test for transmission, hens were placed two rows cages, separated from each other 1 m. One row challenged enteritidis, whereas remained unchallenged but exposed room air. Ventilation...
Experimental infection models are useful tools for understanding how Salmonella enteritidis is deposited in eggs and testing potential strategies to control eggborne transmission of disease humans. Oral inoculation laying hens presumed provide the closest simulation naturally occurring infections, but alternatives such as intravenous or aerosol have sometimes been recommended options induce higher incidences egg contamination. The present study compared frequency, level, location S....
The site of deposition Salmonella enteritidis in eggs could influence the extent to which this pathogen multiplies before refrigeration achieves growth-inhibiting internal temperatures. first part study sought determine whether S. inoculated onto exterior (vitelline) membrane surface egg yolks was able penetrate into and multiply within yolk contents. When 10(2) cfu intact yolks, multiplication interior contents occurred 10% samples after 6 h incubation 75% 24 at 25 C (reaching mean levels...
Effects of age at exposure on the persistence Salmonella in various tissues chicks were assessed two experiments. Broiler chicks, housed wire floors isolation cabinets, orally inoculated with S. typhimurium ages (1 to 8 days after hatching). The postinoculation mortality declined significantly (P<.05) as inoculation increased. One experiment investigated effect cecum. persisted for 7 wk 81.3% 1 day and 62.5% age. mean number cecal was also greater Day than those 8. second examined adherence...