Slaughter Establishments Research Articles

Evaluation of the Microbiological Status of Cattle Carcasses in Mongolia: Considering the Hygienic Practices of Slaughter Establishments.

The meat industry has received great attention in Mongolia, having over 70 million livestock, and is important to the nation's economy. Systematic microbiological testing of carcasses has not been mandatorily regulated in all abattoir premises, and the efficacy of the introduction of the Good Hygiene Practice and Hazard Analysis Critical Control Points (HACCP) to some plants has not yet been tested microbiologically in Mongolia. Therefore, samples were collected from two establishments: plant A with an HACCP certificate from a third party and plant B without an HACCP certificate. The rates and levels of the total bacterial count (TBC) as overall hygiene indicators, the Enterobacteriaceae count (EBC) as fecal contamination indicators, and the Staphylococcus spp. count (SC) as personal hygiene indicators were determined on different parts of beef carcasses. The contamination rates in most parts were lower in plant A than in plant B (e.g., TBC in the rump and flank: 103-105 and 105-107, in plant A vs. 104-106 and 105-108 in plant B, respectively). Plant A also had a lower EBC and SC (p < 0.001). Furthermore, 2 out of 100 beef carcasses (2%) were positive for enterohemorrhagic Escherichia coli as a foodborne pathogen indicator in plant A.

Assessment of United States Department of Agriculture Food Safety Inspection Service Humane Handling Enforcement Actions: 2018-2020.

Federally inspected slaughter establishments in the United States must adhere to the Humane Methods of Slaughter Act and regulations that enforce it. Failure to comply with this law results in a Humane Handling Enforcement Action (HHEA) issued by the United States Department of Agriculture Food Safety Inspection Service (USDA FSIS). The objective of this study was to systematically analyze and describe HHEAs issued between 2018 and 2020. Enforcement action notification letters were accessed from the USDA FSIS website and date, location, regulatory action, reason for noncompliance, species, and follow up action for each HHEA was recorded. Summary statistics (proportions and percentages) were calculated for the entire population dataset. Between 2018 and 2020, FSIS issued 293 HHEAs; 109 in 2018, 85 in 2019, and 99 in 2020. The majority of HHEAs (64.16%; 188 of 293) were related to the mechanical stunning of bovine (39.93%; 117 of 293) and porcine (24.23%; 71 of 293) species. The majority (50.23%; 107 of 213) of causative reasons for mechanical stun failure across all species were not clearly described; however, of those that were, most (39.12%; 68 of 213) were related to the placement of mechanical stuns. Addressing these issues through improved training and research would help to reduce the total number of HHEAs. Additional detail in reporting the events that result in HHEAs from USDA FSIS would aid in guiding corrective actions on an industry-wide scale.

Feral Swine Commercial Slaughter and Condemnation at Federally Inspected Slaughter Establishments in the United States 2017-2019.

Feral swine populations in the United States (US) are capable of carrying diseases that threaten the health of the domestic swine industry. Performing routine, near-real time monitoring for an unusual rise in feral swine slaughter condemnation will increase situational awareness and early detection of potential animal health issues, trends, and emerging diseases. In preparation to add feral swine to APHIS weekly monitoring, a descriptive analysis of feral swine slaughter and condemnations was conducted to understand the extent of commercial feral swine slaughter in the US at federally inspected slaughter establishments and to determine which condemnation reasons should be included. There were 17 establishments that slaughtered 242,198 feral swine across seven states from 2017 to 2019. For all 17 establishments combined, feral swine accounted for 63% of slaughtered animals. A total of 23 types of condemnation reasons were noted: Abscess/Pyemia, Arthritis, Contamination, Deads, Emaciation, General Miscellaneous, Icterus, Injuries, Metritis, Miscellaneous Degenerative & Dropsical Condition, Miscellaneous Inflammatory Diseases, Miscellaneous Parasitic Conditions, Moribund, Nephritis/Pyelitis, Non-ambulatory, Pericarditis, Pneumonia, Residue, Sarcoma, Septicemia, Sexual Odor, Toxemia, and Uremia. Exploratory analysis was conducted to determine which condemnation reasons should be included for weekly monitoring. For most condemn reasons, weeks of unusually high condemnations were noted. For example, a period of high pneumonia condemnations occurred from December 2, 2018 through February 3, 2019 with a spike on January 6, 2019 and a spike in dead swine occurred on November 3, 2019. The seasonal impacts on limited quality food resources, seasonal variation in the pathogen(s) causing pneumonia, and harsher weather are suspected to have an impact on the higher condemnation rates of pneumonia and dead swine during the winter months. Based on condemnation frequencies and the likelihood of enabling situational awareness and early detection of feral swine health emerging diseases, the following were selected for weekly monitoring: abscess/pyemia, contamination/peritonitis, deads, emaciation, injuries, miscellaneous parasitic conditions, moribund, pneumonia and septicemia. Detection of notable increases in condemnation reasons strongly suggestive of foreign animal or emerging diseases should contribute valuable evidence toward the overall disease discovery process when the anomalies are both confirmed with follow up investigation and combined with other types of surveillance.

Effects of Antimicrobial Interventions on Indicator Organisms during Beef Carcass Dressing

Beef slaughter establishments employ many interventions to help minimize the occurrence of pathogens in their products. This study explored the effectiveness of various common interventions on microbial load using the results of the Beef-Veal Carcass Baseline Survey conducted in 2014 to 2015. The Food Safety and Inspection Service analyzed swab samples taken from 1,135 carcasses at 139 establishments. These included paired samples from post-hide removal (before evisceration) and prechill (after evisceration). Samples were tested for pathogens (Salmonella and Shiga toxin-producing Escherichia coli) and indicators (E. coli, Enterobacteriaceae, coliforms, and aerobic count [AC]). The sample size for pathogen-positive samples was small, impeding the establishment of a direct correlation between interventions and pathogens. However, we observed associations between pathogen-positive rate and log AC, indicating similar intervention effectiveness of pathogens and indicators in this study. Generally, the use of interventions reduced indicator concentrations. Each intervention produced a range of effectiveness, suggesting that how interventions are applied may be as important as which interventions are applied. The range of effectiveness for single interventions was a 0.4- to 1.9-log AC reduction; for multihurdle interventions, it ranged from 1.6- to 2.9-log AC reduction. The results of this study may be used by slaughter establishments to help identify effective intervention options for pathogen reduction.

Comparison between the Real-Time PCR and Crystal Diagnostic Xpress Immunoassay Methods for Detecting Salmonella and Shiga Toxin–Producing Escherichia coli in the Air of Beef Slaughter Establishments

The aim of this study was to compare the effectiveness of a quantitative real-time PCR (qPCR) molecular method and the Crystal Diagnostic Xpress (CDx) immunoassay for detecting Salmonella and Shiga toxin-producing Escherichia coli (STEC) in air samples collected from abattoirs in Texas. The 70 air samples were collected from two small and two large meat processing plants in the spring and summer with a wetted wall cyclone air sampler. The samples were divided equally into two parts: one part was used for the qPCR assay, and the other part was enriched for 18 and 36 h and evaluated with the CDx immunoassay. All samples for which positive results were obtained were confirmed by plating and by biochemical and serological tests as recommended by AOAC International to verify results of rapid methods. With the qPCR and CDx assays and 36 h of enrichment, 37.5 and 57.1% of the samples, respectively, were positive for Salmonella (P < 0.05) and 65.0 and 60.7%, respectively, were positive for STEC (P > 0.05). Air samples required longer enrichment for the CDx immunoassay than recommended by the manufacturer for food samples. Recovery of Salmonella and STEC increased 16 and 47%, respectively, when enrichment was extended from 18 to 36 h. The prevalence of Salmonella and STEC obtained with both methods was affected by the size of the processing plant and the processing stage. Detection rates for samples from larger plants were higher for both pathogens. Significantly higher prevalence was obtained for samples from the stunning and dehiding areas than for those from the fabrication rooms and chillers. Salmonella detection was higher with the CDx assay than with the qPCR assay, but no differences were found for the detection of STEC by the qPCR and CDx assays. These results highlight the importance of method adjustments when testing matrices other than foods. More research is needed to understand the dynamics of pathogen dispersal in aerosols and how this affects the effectiveness of current rapid detection methods.

BEM-ESTAR ANIMAL: CARACTERIZAÇÃO DA AMBIÊNCIA E DO MANEJO NA PRODUÇÃO E ABATE DE FRANGOS DE CORTE

O modelo de produção mais utilizado na avicultura brasileira é o sistema de integração entre produtores e frigoríficos, o que permite a análise completa da cadeia produtiva e o estudo sistematizado da correlação entre estrutura, manejo e ambiente proporcionado às aves. Diante deste cenário, objetivou-se identificar os principais pontos vulneráveis da cadeia produtiva de frangos de corte relacionados à ambiência e ao manejo, caracterizando o nível de atendimento das normas de bem-estar animal (BEA) em estabelecimentos de criação e abate de aves, localizados no Sudoeste Goiano. Desta forma, procedeu-se à verificação de recomendações norteadas pelas diretrizes da Humane Farm Animal Care (HFAC) e da Royal Society for the Prevention of Cruelty to Animals (RSPCA) em vinte granjas e três frigoríficos distribuídos pela região amostrada. Os dados foram analisados pelo método descritivo. Como resultado, foram observadas falhas técnicas, de manejo e estruturais nas etapas pré-abate, bem como nos procedimentos industriais nos estabelecimentos avaliados, além da total ausência de enriquecimento ambiental.

Higher line speed in young chicken slaughter establishments does not predict increased Salmonella contamination risks

Do faster slaughter line speeds for young chickens increase risk of Salmonella contamination? We analyze data collected in 2018–2019 from 97 slaughter establishments processing young chickens to examine the extent to which differences in slaughter line speeds across establishments operating under the same inspection system explain observed differences in their microbial quality, specifically frequencies of positive Salmonella samples. A variety of off-the-shelf statistical and machine learning techniques applied to the data to identify and visualize correlations and potential causal relationships among variables showed that the presence of Salmonella or other indicators of process control, such as noncompliance records for regulations associated with process control and food safety, are not significantly increased in establishments with higher line speeds (e.g., above 140 birds per min) compared with establishments with lower line speeds when establishments are operating under the conditions present in this study. This included some establishments operating under specific criteria to obtain a waiver for line speed. A null hypothesis advanced over 30 yr ago by the National Research Council that increased line speeds result in a product that is not contaminated more often than before line speeds were increased, appears to be fully consistent with these recent data.

Salmonella and Shiga Toxin–Producing Escherichia coli in Products Sampled in the Food Safety and Inspection Service Raw Pork Baseline Study

The Food Safety and Inspection Service (FSIS) conducts microbiological baseline studies to determine national prevalence of select foodborne pathogens in federally inspected meat and poultry products and to obtain data for risk assessments. The FSIS conducted a baseline study from 1 June 2017 through 31 May 2018 to characterize and determine the prevalence of Salmonella and assess the occurrence of Shiga toxin-producing Escherichia coli (STEC) in a variety of raw pork products. In total, 4,014 samples from slaughter and processing establishments were analyzed for Salmonella; a subset of these samples (1,395) from slaughter establishments were also analyzed for STEC. Analyses determined that the national prevalence of Salmonella in raw pork products was highest in comminuted products (28.9%), followed by intact cuts (5.3%) and nonintact cuts (3.9%). Less than 1% of samples analyzed were positive for the top seven STEC. Our findings indicate there is a need for additional pathogen reduction strategies for raw pork products.

Multidrug-Resistant Salmonella enterica Subspecies I Serovar 4,[5],12:i:- Isolates Recovered from Food Safety and Inspection Service-Regulated Products and Food Animal Ceca, 2007-2016.

Salmonella enterica subspecies I serovar 4,[5],12:i:- (Salmonella I 4,[5],12:i:-) is among the five most common serovars associated with human salmonellosis in the United States. In 2010, human infections with Salmonella I 4,[5],12:i:- which exhibited resistance to ampicillin, streptomycin, sulfonamides, and tetracycline (ASSuT) emerged as a public health concern. Outbreak investigations identified live animal settings, meat and poultry, and pets as confirmed and suspect sources of infection. To shed further light on possible sources of ASSuT-resistant Salmonella I 4,[5],12:i:- infections, we described isolates recovered from meat and poultry products regulated by the Food Safety and Inspection Service (FSIS) and from food animal ceca collected at FSIS-regulated slaughter establishments during 2007-2016. During the time period of interest, ASSuT-resistant Salmonella I 4,[5],12:i:- was found at low levels in multiple FSIS product classes including swine, turkey, cattle and chicken, which suggests this pathogen has a relatively wide host range. Monitoring trends in the various FSIS production classes over time and developing commodity profiles may help focus preventative strategies.

Relatedness of Salmonella contamination frequency on chicken carcasses and parts when processed in the same establishment

Understanding how changes in the prevalence of Salmonella-positive chicken carcasses affects the prevalence of Salmonella-positive chicken parts samples across slaughter establishments is necessary to model the risk of foodborne illness. When developing new Salmonella performance standards for chicken parts—that were implemented following existing chicken carcass performance standards—FSIS made assumptions regarding the correlation between these two forms of chicken products marketed to consumers. These assumptions were necessary because data were not available at the time to measure this correlation. Using recent FSIS sampling data and covariate information concerning antimicrobials applied during chicken processing, regression analysis suggests a slight negative relationship between the prevalence of Salmonella-positive chicken parts in slaughter establishment and the use of peracetic acid on carcasses, as well as a large positive relationship between prevalence of Salmonella-positive chicken parts and carcasses. Nevertheless, using a repeated random sub-sampling cross-validation approach, the regression model has very limited predictive value. In lieu of a predictive model, estimation of the correlation between prevalence of Salmonella-positive chicken carcass and parts samples is useful for understanding the public health value of performance standards and other interventions applied to these chicken products. After adjusting the observed correlation of the sampling evidence to account for the underlying beta and binomial distribution errors inherent in observed results, the estimated correlation of prevalence of Salmonella-positive chicken carcass and parts is 0.54. This implies a moderate degree of relatedness but may still understate the true correlation because of limitations in the available data.

Food Safety Practices in the U.S. Meat Slaughter and Processing Industry: Changes from 2005 to 2015

Meat slaughter establishments use a multipronged approach to ensure beef and pork products are safe for human consumption. To determine the approaches most commonly used, we conducted a national survey of federally inspected meat slaughter and processing establishments (376 completed surveys, 66% response rate) in 2015. We compared the results with a survey that was conducted in 2005, albeit of potentially different establishments, by using a similar questionnaire and similar data collection methods, thus allowing for an evaluation of trends in food safety practices over time. The use of some food safety practices has increased over the 10-yr time period, whereas others remained the same or decreased. For example, the use of chemical sanitizers or hot water for food contact surfaces and tools increased from 51 to 93%. As another example, microbiological testing of raw meat after fabrication, in addition to that required by regulation, increased from 50 to 72%. However, the use of organic acid rinse on carcasses in the slaughter area remained the same, at 66% of establishments. Written policies and procedures to control the use of hazardous chemicals decreased from 75 to 65% of establishments. The survey findings can be used to characterize food safety practices and technologies in the meat slaughter and processing industry and identify areas for improvement.

Use of Temperature, Humidity, and Slaughter Condemnation Data to Predict Increases in Transport Losses in Three Classes of Swine and Resulting Foregone Revenue.

The United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) conducts weekly surveillance of slaughter condemnation rates to provide early warning for emerging diseases and to monitor health trends in swine. Swine deaths in-transit are an animal welfare concern and represent lost revenue for the swine industry. This retrospective observational study used ambient temperature and humidity data from weather stations near United States slaughter plants collected from 2010 to 2015 to predict the incidence and risk of death among swine in-transit and just prior to slaughter. The risk of death for market swine at a heat index (HI), which combines the effects of temperature and humidity, indicating moderately hot weather conditions between 85 and 92°F was 1.37 times greater than that of the baseline temperature range of 54–79°F. The risk of death for cull sows at an HI between 85 and 92°F was 1.93 times greater than that of average temperatures ranging from 54 to 79°F. Roaster swine (weigh < 220 lbs and often used for whole carcass roasting), however, had 0.80 times the risk when the HI was 85–92°F compared to a baseline temperature of 54–79°F. The risk of death for roaster swine at a minimum temperature between 40 and 50°F was 1.21 times greater than that of average temperatures ranging from 54 to 79°F. The risk of death for market swine at a minimum temperature range of 40–50°F was 0.97 times that of average temperatures ranging from 54 to 79°F. And for cull sows, the risk of death at a minimum temperature range of 40–50°F was 0.81 times the risk at the average temperature ranging from 54 to 79°F. Across the study period, cumulative foregone revenue, or revenue not realized due to swine condemnations, for all swine was $18.6 million and $4.3 million for cold temperatures and high HI ranges above the baseline, respectively. Marginal foregone revenue per hog in hotter months is higher due to seasonal peaks in swine prices. As a result of this study, the USDA-APHIS swine condemnation surveillance can incorporate weekly estimated HI values and ambient temperature data for slaughter establishments to provide additional information for analysts investigating signals (noteworthy increases above baseline) for “dead” condemnations. This study suggests that current mitigation measures are often not sufficient to prevent swine deaths due to ambient temperature extremes.

Prevalencia de &lt;i&gt;Fasciola Hepatica&lt;/i&gt; y pérdidas económicas asociadas al decomiso de hígados en tres mataderos de clase a de Costa Rica

Para estimar la prevalencia anual y mensual de Fasciola hepatica y las pérdidas económicas anuales asociadas al decomiso de hígados por presencia del parásito, se analizaron los registros del Ministerio de Agricultura y Ganadería de Costa Rica, Dirección de Inocuidad de Productos de Origen Animal (DIPOA), para el 2014, provenientes de 3 mataderos clase A localizados en el área metropolitana de Costa Rica; en estos mataderos se sacrificaron 249 108 reses, de las cuales 4547 hígados fueron decomisados por presencia de F. hepatica en el órgano. Las mayores prevalencias, entre 2,33 y 2,55%, se presentaron en enero, febrero y marzo, y las menores, entre 1,32 y 1,56%, durante agosto, setiembre y octubre. La prevalencia anual según estos registros fue 1,83% (IC 95%: 1,77-1,88). Las pérdidas económicas asociadas al decomiso de hígados fueron de 36.379.000 CRC, equivalentes a 67.438 USD. Se resalta el perjuicio económico de este parásito a nivel nacional y la utilidad del decomiso y registro de vísceras afectadas en los establecimientos de sacrificio de bovinos, como herramienta diagnóstica para la vigilancia epidemiológica, disponible para conocer sobre el estado de esta parasitosis. Como alternativas de control y prevención de la enfermedad, se plantea considerar las condiciones específicas de las regiones afectadas y así controlar esta parasitosis con un manejo integral, que involucre la fuente de alimento, desparasitación regular del ganado, con registro y monitoreo farmacológico de las drogas utilizadas, y saneamiento ambiental en fincas afectadas.

Using a Six Sigma Fishbone Analysis Approach To Evaluate the Effect of Extreme Weather Events on Salmonella Positives in Young Chicken Slaughter Establishments

A six sigma fishbone analysis approach was used to develop a machine learning model in SAS, Version 9.4, by using stepwise linear regression. The model evaluated the effect of a wide variety of variables, including slaughter establishment operational measures, normal (30-year average) weather, and extreme weather events on the rate of Salmonella -positive carcasses in young chicken slaughter establishments. Food Safety and Inspection Service (FSIS) verification carcass sampling data, as well as corresponding data from the National Oceanographic and Atmospheric Administration and the Federal Emergency Management Agency, from September 2011 through April 2015, were included in the model. The results of the modeling show that in addition to basic establishment operations, normal weather patterns, differences from normal and disaster events, including time lag weather and disaster variables, played a role in explaining the Salmonella percent positive that varied by slaughter volume quartile. Findings show that weather and disaster events should be considered as explanatory variables when assessing pathogen-related prevalence analysis or research and slaughter operational controls. The apparent significance of time lag weather variables suggested that at least some of the impact on Salmonella rates occurred after the weather events, which may offer opportunities for FSIS or the poultry industry to implement interventions to mitigate those effects.

The Importance of Governance Levels in Alternative Food Networks: The Case of Red Meat Inspection Rules

AbstractFocusing on U.S. red meat inspection regulations, in the context of alternative food networks (AFNs), we explore the implications of different levels of governmental governance for the number of red meat slaughter establishments in the United States. We argue that disaggregating “the state” makes possible a more nuanced consideration of the effects of different tiers of governance. We use regression analysis with data for 40 U.S. states over 40 years to examine the effects of state (subnational) inspection programs and implementation of the federal Hazard Analysis and Critical Control Point (HACCP) regulations on the number of slaughter establishments by type. In this analysis we test two common beliefs among AFN actors: that state inspection helps, and HACCP hurts, small slaughter establishments. It also allows us to make a case for disaggregating governance tiers as we find that state inspection programs and HACCP have significant and opposite effects on the number of federally and non–federally inspected slaughter establishments. Our analysis supports the belief that state inspection is important to small slaughter establishments, but does not support the belief that HACCP has had a negative effect on them. Our conclusion is that agrifood scholars need to pay attention to different forms of governmental governance even with the increased focus on private and third‐party certifications.

Avaliação do bem estar animal durante o manejo pré abate e abate em um matadouro-frigorífico

Studies on Animal Welfare have importance to veterinary and scientific community in view of the small amount of work in this area. Taking into account that Brazil is one of the largest exporters of beef, pork and chicken, and that importing countries are demanding these products, increasingly, the use of practices that respect the Animal Welfare, it is evident the need to know the reality of the slaughter establishments. Aiming to achieve a quality standard under the commercial point of view and humane slaughter. In this sense it is proposed to a survey in order to investigate the levels of Animal Welfare, through the evaluation of management practices and slaughter in a slaughter plant in Uberlandia - MG. Data were collected through a standardized questionnaire in seven site visits, evaluating indicators in the stages of pre-slaughter and slaughter. After collection, the data were processed and arranged in tables. For analysis, data were transformed into indicators and compared with the literature. This comparison showed the presence of indicators of Animal Welfare, among the subjects studied in the slaughter plant, in violation of the Animal Welfare levels accepted. We conclude that the presence in the slaughterhouse assessed for indicators of Animal Welfare outside the acceptable standards is associated with factors such as inadequate management due to lack of training and insufficient level of knowledge about animal behavior, by employees.

Ocorrência de Escherichia coli em meias carcaças de bovinos abatidos em estabelecimento habilitado para exportação

A análise de Escherichia coli, considerada bactéria indicadora de contaminação fecal, é utilizada na verificação do controle de processos de abate. Porém, poucos trabalhos foram publicados acerca da ocorrência desse micro-organismo nas indústrias de abate brasileiras. Assim, o presente estudo determinou a ocorrência de E. coli genérica em carcaças bovinas em um estabelecimento sob inspeção federal, habilitado à exportação, identificando as possíveis variações no ano de 2010. Foram coletadas 1111 amostras de suabe de superfície de meias carcaças bovinas e analisadas pela metodologia Petrifilm™. A ocorrência encontrada foi de 4,4% (IC95%=3,3%; 5,7%), com uma média de contagem de 4,08UFC cm-2, não sendo significativamente afetada pelas estações de seca e chuva. As maiores ocorrências foram observadas nos meses de setembro (8,7%) e outubro (16,7%), no qual também foi detectada a maior média de contagem (14,06UFC cm-2). A diferença nos valores observada nesses períodos pode estar relacionada com o sistema de criação dos animais. A ocorrência foi significativamente maior no primeiro turno de abate (6,2%), em comparação com o segundo (1,6%), indicando uma possível relação entre a presença do micro-organismo e a realização de procedimentos operacionais. Interpretando-se os resultados encontrados, conclui-se que há necessidade da determinação de um perfil para a ocorrência de E. coli genérica em cada estabelecimento, considerando os fatores que a alteram, para orientar e tornar mais efetivas as medidas preventivas e corretivas de controle dos processos de abate e reduzir a contaminação microbiana das carcaças.

Risk assessment of intervention strategies for fallen carcasses in beef slaughter establishments

In the slaughter establishment, cattle carcasses move along the line attached to a slaughter chain. Cattle carcasses fall off the slaughter chain infrequently, but such an event results in carcasses potentially contaminated with bacteria that exist on floors and equipment. Microbes in the feces and ingesta of slaughtered livestock as well as microbes on the hide surfaces of those livestock contaminate the slaughter environment. This environment often will include important foodborne pathogens, such as Escherichia coli O157:H7. This analysis uses a risk assessment modeling approach to assess the potential public health effects of standardizing treatments for carcasses that fall off the slaughter chain at dehiding. This assessment examines combinations of six intervention options: 1) water rinse, 2) organic acid rinse, 3) trim, 4) organic acid rinse and trim, 5) carcass trimming and cook, 6) condemn the carcass. Potential improvement in public health results from progressive removal of the least effective of these intervention options. The results of this analysis indicate that the number of annual human E. coli O157:H7 illnesses avoided varies based on intervention type—organic acid rinsing (281), carcass trimming (787), organic acid rinsing plus trimming (1533), trimming plus cooking (1539), and carcass condemnation (1520). The model suggests that the numbers of illnesses prevented are largest and similar when either the organic acid plus trim, trim plus cook, or condemn interventions are set as the minimum. This conclusion was robust to sensitivity analysis of various uncertainties in the model. Interestingly, it was found that a universal condemnation of fallen cattle was not a necessary intervention. Although it was assumed that most large slaughter establishments currently implement a trimming plus cooking intervention for all fallen carcasses, the model suggests there is little difference among the three best interventions.

Development and validation of a streamlined method designed to detect residues of 62 veterinary drugs in bovine kidney using ultra‐high performance liquid chromatography – tandem mass spectrometry

In the USA, the US Department of Agriculture's Food Safety and Inspection Service (FSIS) conducts the National Residue Program designed to monitor veterinary drug and other chemical residues in beef and other slaughtered food animals. Currently, FSIS uses a 7-plate bioassay in the laboratory to screen for antimicrobial drugs in bovine kidneys from those animals tested positive by inspectors in the slaughter establishments. The microbial inhibition bioassay has several limitations in terms of monitoring scope, sensitivity, selectivity, and analysis time. Ultra-high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) has many advantages over the bioassay for this application, and this study was designed to develop, evaluate, and validate a fast UHPLC-MS/MS method for antibiotics and other high-priority veterinary drugs in bovine kidney. Five existing multi-class, multi-residue methods from the literature were tested and compared, and each performed similarly. Experiments with incurred samples demonstrated that a 5-min shake of 2 g homogenized kidney with 10 ml of 4/1 (v/v) acetonitrile/water followed by simultaneous clean-up of the initial extract with 0.5 g C18 and 10 ml hexane gave a fast, simple, and effective sample preparation method for the <10 min UHPLC-MS/MS analysis. An extensive 5-day validation process demonstrated that the final method could be used to acceptably screen for 54 of the 62 drugs tested, and 50 of those met qualitative MS identification criteria. Quantification was not needed in the application, but the method gave ≥ 70% recoveries and ≤ 25% reproducibilities for 30 of the drugs.

Examining the occurrence of residues of flunixin meglumine in cull dairy cows by use of the flunixin cull cow survey

To determine whether cull dairy cows with signs of certain clinical conditions, termed suspect, are more likely than healthy-appearing cull dairy cows to have violative concentrations of flunixin meglumine in their tissues at slaughter. Cross-sectional study. 961 cull dairy cows. Suspect cull dairy cows were selected from 21 beef slaughter establishments with a high production volume of dairy cows, and kidney and liver tissues were collected for screening. Kidney tissues were screened for antibiotics and sulfonamides with the fast antimicrobial screening test (FAST). Liver tissues were screened for flunixin meglumine with an ELISA, and quantitative analysis of ELISA-positive samples was performed with high-performance liquid chromatography. During the same time period, liver tissues from 251 healthy-appearing cull dairy cows were collected for the Food Safety and Inspection Service National Residue Program Scheduled Sampling Plan, but were screened only for flunixin meglumine. Of 710 suspect cull dairy cows, 50 (7.04%) had liver tissue flunixin concentrations higher than the flunixin tolerance concentration (0.125 ppm). Thirty-one of 168 (18.45%) FAST-positive and 19 of 542 (3.51%) FAST-negative suspect cull dairy cows had violative tissue flunixin concentrations. Two of the 251 (0.80%) healthy-appearing cull dairy cows had violative tissue flunixin concentrations. Suspect cull dairy cows, especially those that were also FAST positive, had a significantly higher incidence of violative tissue flunixin concentrations than healthy-appearing cull dairy cows at slaughter. Targeted sampling plans for flunixin meglumine in suspect dairy cows can help to support more efficient use of resources and further safeguard the nation's food supply.