Association between animal welfare indicators and microbiological quality of beef carcasses, including Salmonella spp., from a slaughterhouse in Ecuador

BACKGROUND AND AIM: Pre-slaughter management and slaughter operations are considered critical factors for animal welfare and meat quality. Previous studies have found poor animal welfare management at municipal slaughterhouses in Ecuador, and little is known about how this affects the microbiological quality of the meat. Therefore, the aim of the study was to analyze the association of the microbiological quality of beef carcasses and animal welfare indicators in a municipal slaughterhouse in Ecuador. MATERIALS AND METHODS: Data for 6 months were collected from a municipal slaughterhouse in Ecuador. Five trained researchers were strategically located along the slaughter process. A total of 351 animals were observed with regard to welfare indicators, and their carcasses were sampled to evaluate microbiological quality. Antemortem (slipping, falling, and vocalization) and postmortem animal welfare indicators (bleed interval, pH, temperature, and bruises) were measured. To determine the total aerobic bacteria (TAB) and Escherichia coli counts and the presence of Salmonella spp., we collected samples by swabbing four different points of each carcass. The association between microbiological quality and animal welfare indicators was studied using univariate and multivariate logistic regressions. RESULTS: The mean TAB count was 5.3 log CFU/cm(2), and the mean total count of E. coli was 2.4 log CFU/cm(2). Salmonella spp. were isolated in 3.1% of the carcasses. An electric goad was used in all animals, 19.1% slipped at least once, and 19.9% vocalized. The mean pH of the carcasses was 7.2, and 79.2% of carcasses had bruises. Multivariate analysis showed that Salmonella spp. and the TAB count were associated with pH and the number of bruises (p = 0.01 in both cases). CONCLUSION: Although there was non-significant association between the majority of animal welfare indicators and microbiological quality, the poor management affecting animal welfare and carcass hygiene are worrisome.