Predictive model for the survival, death, and growth of Salmonella typhimurium in broiler hatchery

Abstract

Contamination and penetration of salmonellae into hatching eggs may comprise an important link in the transmission of these bacteria to growing birds, processed carcasses, and eventually to the consumer. In this study, a predictive model for Salmonella typhimurium as a function of initial cell number and storage or incubation time at a nearly constant temperature and humidity was developed and evaluated to compute the bacterial load after 1 d (holding), 10 d (candling), 17 d (incubation), and 21 d (chick processing). Experiments were conducted for S. typhimurium with both high initial bacterial load (HIBL) and low initial bacterial load (LIBL) of 6.0 and 3.5 log cfu/egg, respectively. Eggs with HIBL experienced 2.0 log reduction in the bacterial load after holding at 4 degrees C for 24 h and 3.0 log increase in the bacterial load during incubation and hatch at approximately 37 degrees C between 17 d and 21 d. Experimental data showed that bacterial load of S. typhimurium from holding to chick processing changed from 3.7 to 6.6 log cfu/egg and from 3.7 to 2.7 log cfu/egg in HIBL and LIBL eggs, respectively. The developed model was able to predict bacterial load of S. typhimurium from 3.6 to 6.6 log cfu/egg in HIBL eggs and from 3.4 to 2.7 log cfu/egg in LIBL eggs from holding to chick processing. Root mean square errors and plot of predicted compared with observed bacterial load of S. typhimurium in contaminated eggs yielded a good fit and prediction. The predicted and experimental results indicated that incubated broiler eggs have an increase in internal bacterial loads between incubation and hatch. This model can be used as a tool to predict bacterial load of S. typhimurium in contaminated eggs as well as help predict the behavior of S. typhimurium during hatch.

Observations on the distribution and control of Salmonella in commercial broiler hatcheries in Great Britain

“…(1997). This is consistent with a report by Pradhan et al (2005) in which it was noted that incubated broiler eggs have an increase in bacterial load between incubation and hatching. Furthermore, eggs contaminated by Salmonella are likely to contaminate other chicks in the same hatcher when they hatch and release fluff (Cason et al., 1994).…”

“…An increase in Salmonella-positive samples from setters onwards was also found by R. H. Davies et al (1997). This is consistent with a report by Pradhan et al (2005) in which it was noted that incubated broiler eggs have an increase in bacterial load between incubation and hatching. Furthermore, eggs contaminated by…”

Observations on the distribution and control ofSalmonellain commercial duck hatcheries in the UK

“…The hatcher area was also found to be a focus of contamination. During incubation and at hatch the Salmonella bacterial loads in contaminated eggs may increase from 3.7 to 6.6 log 10-cfu/egg (Pradhan et al, 2005). On hatch, seeder birds infect birds in the same or adjacent hatching trays .…”

Predictive modelling of Salmonella: From cell cycle measurements to e-models

“…A number of authors have used this new reparameterisation to fit Salmonella growth data measured by different methods: plate counts Juneja et al, 2009;Oscar, 2007); conductance (Koutsoumanis, Tassou, et al, 1998); and absorbance measurements (Park, Seo, & Ha, 2007). Models were generated in specific foods such as meat (Juneja et al, 2009), egg (Pradhan, Li, Swem, & Mauromoustakos, 2005) and poultry Oscar, 2007;Yang, Wang, Li, & Johnson, 2002).…”