title: Quantitative examination of Salmonella spp. in the lairage environment of a pig abattoir.
abstract: One of the initial sources of Salmonella spp. and other bacterial pathogens at the abattoir is the carrier pig. In the absence of effective cleaning and disinfection measures, such animals may contaminate the lairage environment, which may act as a significant source of infection for incoming non-infected animals. The objectives of this study were to quantify the levels of Salmonella spp. in the lairage of a large pig abattoir and to compare the effect on environmental contamination levels with Salmonella spp. of the cleaning procedures carried out daily to those undertaken weekly. A total of 359 swabs were collected from lairage pen floors at three timepoints throughout the course of two slaughter days. All samples were analyzed quantitatively. On day 1, Monday, following weekly cleaning and disinfection, 6% of the 179 floor swabs taken were positive for Salmonella spp. On day 2, Thursday, at the end of the slaughter week, when lairage pens were subjected to high-pressure cold water washing between batches of pigs, 44% of the 180 floor swabs taken were positive for Salmonella spp. Quantitative analysis revealed that the median numbers of salmonellae detected following weekly cleaning and disinfection were approximately 1.8 organisms/100 cm(2). The numbers of salmonellae detected on day 2 were approximately 8 organisms/100 cm(2). The most prevalent serotype isolated in this study was S. Typhimurium (42%). Phage types DT12, DT104b, and U302 comprised the majority of phage types identified. These results highlight the need to develop effective intervention measures to control the spread of Salmonella spp. in the preslaughter environment.
authors: Veterinary Sciences Centre, School of Agriculture, Food Science, and Veterinary Medicine, University College Dublin, Dublin, Ireland.
authors: Claire
authors: C
authors: Boughton
authors: John
authors: J
authors: Egan
authors: Gabrielle
authors: G
authors: Kelly
authors: Bryan
authors: B
authors: Markey
authors: Nola
authors: N
authors: Leonard
mesh_terms: D000003:Abattoirs / Q000592:standards*; D000818:Animals; D002353:Carrier State / Q000662:veterinary; D015169:Colony Count, Microbial; D004197:Disease Reservoirs / Q000662:veterinary; D004783:Environmental Microbiology; D005430:Floors and Floorcoverings; D005506:Food Contamination / Q000517:prevention & control*; D006801:Humans; D006920:Hygiene; D015995:Prevalence; D012475:Salmonella / Q000145:classification / Q000302:isolation & purification*; D012703:Serotyping; D013552:Swine / Q000382:microbiology*