Modeling the survivability ofSalmonella typhimuriumin the chicken cecae using an anaerobic continuous-culture of chicken cecal bacteria

Abstract

To cite this article: David J. Nisbet (2000) Modeling the survivability of Salmonella typhimurium in the chicken cecae using an anaerobic continuous-culture of chicken cecal bacteria,

Cell yields and fermentation responses of a Salmonella Typhimurium poultry isolate at different dilution rates in an anaerobic steady state continuous culture

“…Chemostats were sterilized (40 min at 1.48 kg/cm 2 pressure and at 121°C) containing 500 ml LB medium each. Chemostats were maintained anaerobically with a constant stream of O 2 -free CO 2 (Nisbet et al 2000) at 39°C with agitation at 100 rpm. The two chemostats were operated concurrently and used to demonstrate changes in dilution rates (D).…”

“…Using markers to determine passage rates, Tukey et al (1958) observed an initial appearance of excreta 2-2.5 h after intake, such that most of the marker was excreted within 12 h. Adequate feed retention time is essential, especially in the ceca, to encourage sufficient microbial degradation of feed substrate for extended time periods (McNab 1973). The continuous culture model has been proven to simulate bacterial interaction of microbial ecosystems such as the GI tract of chickens (Nisbet et al 2000). Previously we have shown that pH shifts in continuous culture could alter genetic responses of ST (Dunkley et al 2008b).…”

Control of Salmonella in Poultry Through Vaccination and Prophylactic Antibody Treatment

“…Reduction in colonisation by S. Typhimurium is problematic, even in vaccinated chicks. While good reduction has been observed when chicks are challenged with 10 4 cfu, reduction is poor at higher challenge doses (10 6 and 10 8 cfu; Nisbet et al, 2000;Clifton-Hadley et al, 2002). Methner et al (1999) showed a 0.5-1.5 log 10 cfu reduction in carriage in vaccinated chicks challenged with variable populations of S. Typhimurium.…”

“…Regardless of challenge dose, Nisbet et al (2000) showed a 2 log 10 reduction in Salmonella establishing in the caeca whereas Clifton-Hadley et al (2002) suggested that high challenge doses of highly invasive and virulent S. Typhimurium may overcome those components of the immune system associated with the systemic phase of infection. Therefore, the 10 4 cfu challenge is the minimum dosage that will not overwhelm the immune system and still results in colonisation of non-vaccinated controls.…”

“…The literature suggests that a stable anaerobic microflora, low house density, bacterial interference, breed resistance, antagonism, colonisation resistance, barrier effects, challenge strain virulence, competitive exclusion and passive immunity could all contribute to low challenge rates (Lloyd et al, 1977;Fuller, 1989;Mead and Barrow, 1990;Kottom et al, 1995;Duchet-Suchaux et al, 1997;Nisbet et al, 2000;Quinn et al, 2000;Chambers and Lu, 2002;Kinde et al, 2005).…”