TY - JOUR
T1 - Factors influencing Salmonella carcass prevalence in Danish pig abattoirs
AU - Freitas de Matos Baptista, Filipa
AU - Dahl, J.
AU - Nielsen, Liza Rosenbaum
N1 - Copyright (c) 2010 Elsevier B.V. All rights reserved.
PY - 2010/7
Y1 - 2010/7
N2 - The Danish Salmonella Surveillance-and-Control Programme in finisher pigs includes both herd and carcass surveillance. Herd surveillance consists of serological testing of meat-juice samples and classification of herds into three Salmonella seroprevalence levels. At the abattoirs, carcass swabs from five pigs are collected daily and analysed as a pooled sample to evaluate the Salmonella carcass prevalence. This study aimed to investigate factors associated with Salmonella carcass prevalence in Denmark. A total of 20,196 pooled carcass swabs collected in 23 Danish abattoirs were included in the analysis. A multilevel logistic regression model was used taking into account the two-level data structure (abattoir, carcass pool) and adjusting the parameter estimates to the random variation at the abattoir level. Study results indicated that carcass contamination was mainly influenced by the probability that at least one pig contributing to the pool was seropositive, the log-transformed number of seropositive pigs delivered to the abattoir on the same day and weekday. No other factors were found to be significant (P>0.05). Large reductions in the number of seropositive pigs delivered to slaughter are unlikely to result in large reductions of the Salmonella carcass prevalence, unless the number of seropositive pigs can be kept below approximately 200. On average, individual Salmonella carcass prevalence can be kept below 1% by keeping a Salmonella input to the abattoir below approximately 50 seropositive pigs. Variation between abattoirs suggested that improved hygiene practices in some of the abattoirs would reduce the Salmonella carcass prevalence further.
AB - The Danish Salmonella Surveillance-and-Control Programme in finisher pigs includes both herd and carcass surveillance. Herd surveillance consists of serological testing of meat-juice samples and classification of herds into three Salmonella seroprevalence levels. At the abattoirs, carcass swabs from five pigs are collected daily and analysed as a pooled sample to evaluate the Salmonella carcass prevalence. This study aimed to investigate factors associated with Salmonella carcass prevalence in Denmark. A total of 20,196 pooled carcass swabs collected in 23 Danish abattoirs were included in the analysis. A multilevel logistic regression model was used taking into account the two-level data structure (abattoir, carcass pool) and adjusting the parameter estimates to the random variation at the abattoir level. Study results indicated that carcass contamination was mainly influenced by the probability that at least one pig contributing to the pool was seropositive, the log-transformed number of seropositive pigs delivered to the abattoir on the same day and weekday. No other factors were found to be significant (P>0.05). Large reductions in the number of seropositive pigs delivered to slaughter are unlikely to result in large reductions of the Salmonella carcass prevalence, unless the number of seropositive pigs can be kept below approximately 200. On average, individual Salmonella carcass prevalence can be kept below 1% by keeping a Salmonella input to the abattoir below approximately 50 seropositive pigs. Variation between abattoirs suggested that improved hygiene practices in some of the abattoirs would reduce the Salmonella carcass prevalence further.
KW - Abattoirs
KW - Animals
KW - Antibodies, Bacterial
KW - Denmark
KW - Hygiene
KW - Prevalence
KW - Risk Factors
KW - Salmonella
KW - Salmonella Food Poisoning
KW - Salmonella Infections, Animal
KW - Sentinel Surveillance
KW - Seroepidemiologic Studies
KW - Swine
KW - Swine Diseases
U2 - 10.1016/j.prevetmed.2010.04.007
DO - 10.1016/j.prevetmed.2010.04.007
M3 - Journal article
C2 - 20537741
SN - 0167-5877
VL - 95
SP - 231
EP - 238
JO - Preventive Veterinary Medicine
JF - Preventive Veterinary Medicine
IS - 3-4
ER -