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This study evaluated the use of endemic enteric coronaviruses polymerase chain reaction (PCR)-negative testing results as an alternative approach to detect the emergence of animal health threats with similar clinical diseases presentation. This retrospective study, conducted in the United States, used PCR-negative testing results from porcine samples tested at six veterinary diagnostic laboratories. As a proof of concept, the database was first searched for transmissible gastroenteritis virus (TGEV) negative submissions between January 1st, 2010, through April 29th, 2013, when the first porcine epidemic diarrhea virus (PEDV) case was diagnosed. Secondly, TGEV- and PEDV-negative submissions were used to detect the porcine delta coronavirus (PDCoV) emergence in 2014. Lastly, encountered best detection algorithms were implemented to prospectively monitor the 2023 enteric coronavirus-negative submissions. Time series (weekly TGEV-negative counts) and Seasonal Autoregressive-Integrated Moving-Average (SARIMA) were used to control for outliers, trends, and seasonality. The SARIMA's fitted and residuals were then subjected to anomaly detection algorithms (EARS, EWMA, CUSUM, Farrington) to identify alarms, defined as weeks of higher TGEV-negativity than what was predicted by models preceding the PEDV emergence. The best-performing detection algorithms had the lowest false alarms (number of alarms detected during the baseline) and highest time to detect (number of weeks between the first alarm and PEDV emergence). The best-performing detection algorithms were CUSUM, EWMA, and Farrington flexible using SARIMA fitted values, having a lower false alarm rate and identified alarms 4 to 17 weeks before PEDV and PDCoV emergences. No alarms were identified in the 2023 enteric negative testing results. The negative-based monitoring system functioned in the case of PEDV propagating epidemic and in the presence of a concurrent propagating epidemic with the PDCoV emergence. It demonstrated its applicability as an additional tool for diagnostic data monitoring of emergent pathogens having similar clinical disease as the monitored endemic pathogens.

Fomites might be responsible for virus introduction in swine farms, highlighting the importance of implementing practices to minimize the probability of virus introduction. The study's objective was to assess the efficacy of different combinations of temperatures and holding-times on detecting live PRRSV and PEDV on surfaces commonly found in supply entry rooms in swine farms. Two PRRSV isolates (MN 184 and 1-4-4 L1C variant) and one PEDV isolate (NC 49469/2013) were inoculated on cardboard and aluminum. An experimental study tested combinations of four temperatures (20°C, 30°C, 40°C, and 50°C) and six holding-times (15 minutes, 60 minutes, 6 hours, 12 hours, 24 hours, and 36 hours) for the presence of the viruses on each surface type. After virus titration, virus presence was assessed by assessing the cytopathic effects and immunofluorescence staining. The titers were expressed as log10 TCID50/ml, and regression models; half-lives equations were calculated to assess differences between treatments and time to not detect the live virus. The results suggest that the minimum time that surfaces should be held to not detect the virus at 30°C was 24 hours, 40°C required 12 hours, and 50°C required 6 hours; aluminum surfaces took longer to reach the desired temperature compared to cardboard. The results suggest that PRRSV 1-4-4 L1C variant had higher half-lives at higher temperatures than PRRSV MN 184. In conclusion, time and temperature combinations effectively decrease the concentration of PRRSV and PEDV on different surfaces found in supply entry rooms in swine farms.

The control of porcine reproductive and respiratory syndrome virus (PRRSV) hinges on monitoring and surveillance. The objective of this study was to assess PRRSV RNA detection by RT-PCR in tongue tips from dead suckling piglets compared to serum samples, processing fluids, and family oral fluids. Tongue tips and serum samples were collected from three PRRSV-positive breeding herd farms (farms A, B, and C) of three different age groups: newborns (

Porcine reproductive and respiratory syndrome virus (PRRSV) became pandemic in the 1980's and today remains one of the most significant pathogens of the global swine industry. At the herd level, control of PRRSV is complicated by its extreme genetic diversity and its ability to persist in pigs, despite an active immune response. Ultimately, PRRSV control or elimination requires the coordination and active cooperation of producers and veterinarians at the regional level. Early voluntary PRRSV regional control programs focused on routine diagnostic testing and voluntary data-sharing regarding the PRRSV status of participants' herds, but no pre-defined action plans or decision trees were developed to secure project successes (or recover from failures). Given that control of PRRSV is paramount to producer profitability, we propose a coordinated approach for detecting, controlling, and ultimately eliminating wild-type PRRSV from herds participating in regional projects. Fundamental to project success is real-time, multi-platform communication of all data, information, and events that concern the regional project and project participants. New to this approach is the concept of agreed-upon action plans to be implemented by project participants in response to specific events or situations. The simultaneous and coordinated implementation of these strategies allows for early detection of wild-type PRRSV virus introductions and rapid intervention based on agreed-upon response plans. An example is given of a project in progress in the Midwest USA.

Developing and raising replacement heifers requires a large capital investment for producers. Therefore, it is imperative to discover traits and management practices to eliminate subfertile heifers prior to breeding and pregnancy determination. In this study, four years of data was analyzed from a centralized beef heifer development yard in the Midwest of the United States. The objective of this study was to analyze various heifer physical characteristics and management practices in order to quantify their impact on pregnancy and date of conception. Logistic regression models were built to investigate risk factors associated with conception to artificial insemination (AI), pregnancy by natural service after AI exposure, and pregnancy in the first 21-days of the breeding season. Age at entry, average daily gain from entry to breeding, pelvic width, and year were associated with AI pregnancy (p < 0.05). On the second model, average daily gain from entry to yearling weight, weight at breeding, weight at pregnancy diagnosis, and age at AI were significantly associated with pregnancy. There were no associations with reproductive tract score with any of the response variables analyzed. These results indicate there are physical measurements that can be used to improve the ability to select and develop heifers for improved reproductive performance.

Aims: Atrial fibrillation (AF) is a public health problem and its prevalence is increasing worldwide. Electronic cohorts, with large electrocardiogram (ECG) databases linked to mortality data, can be useful in determining prognostic value of ECG abnormalities. Our aim is to evaluate the risk of mortality in patients with AF from Brazil. Methods: This observational retrospective study of primary care patients was developed with the digital ECG database from the Telehealth Network of Minas Gerais, Brazil. ECGs performed from 2010 to 2017 were interpreted by cardiologists and the University of Glasgow automated analysis software. An electronic cohort was obtained linking data from ECG exams and those from a national mortality information system, using standard probabilistic linkage methods. We considered only the first ECG of each patient. Patients under 16 years were excluded. Hazard ratios (HR) for mortality were adjusted for demographic and self-reported clinical factors and estimated with Cox regression. Results: From a dataset of 1,773,689 patients, 1,558,421 were included, mean age 51.6 years; 40.2% male. There were 3.34% deaths from all causes in 3.68 years of median follow up. The prevalence of AF was 1.33%. AF was an independent risk factor for all-cause mortality (HR 2.10, 95%CI 2.03–2.17) and cardiovascular mortality (HR 2.06, 95%CI 1.86–2.29). Females with AF had a higher risk of overall and cardiovascular mortality compared with males (p < 0.001). Conclusions: AF was a strong predictor of cardiovascular and all-cause mortality in a primary care population, with increased risk in women. Condensed abstract To assess risk of mortality in AF patients, an electronic cohort was obtained linking data from ECG exams of Brazilian primary care patients and a national mortality information system. From 1,558,421 patients, AF (prevalence 1.33%) carried a higher risk of overall and cardiovascular mortality, with increased risk in women. What’s New This is the first study with a large Brazilian electronic cohort to evaluate the risk of mortality linked to AF in primary care patients. AF patients from a Brazilian primary care population had a higher risk of death for all causes (HR 2.10, 95%CI 2.03–2.17) and cardiovascular mortality (HR 2.06, 95%CI 1.86–2.29). Female patients with AF had an increased risk of overall and cardiovascular mortality compared with male patients (p < 0.001).

Abstract: In this retrospective study was determined the frequency of canine skin peripheral nerve sheath tumors (PNST) in cases diagnosed by the Setor de Patologia Veterinária of the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, between the years 2000 and 2012. The canine profiles, as well as histological, immunohistochemical and prognostic aspects of the tumors were based on 70 samples, comprising 40 females, 29 males and one unspecified sample. Between 2000 and 2012, 2,984 skin tumors of dogs were diagnosed in the SPV-UFRGS, totaling 2.34% of skin neoplasms in dogs. Animals that comprised the largest amount of samples (43%) were those with no breed (SRD), followed by German Shepherds (10%). Females were more affected than males (40/70 - 57% and 29/70 - 41% respectively). Skin PNST of this research showed predominant localization on the limbs (40% in the forelimbs and 29% in the hindlimbs); affecting adult dogs, mostly aged between 8 and 11 years (54%). The samples were routinely processed for hematoxylin and eosin, and were also evaluated by toluidine blue and Masson's trichrome staining, and immunohistochemistry (IHC) anti-vimentin, -S-100, -GFAP, -actin, von Willebrand factor and neurofilament. Anisocytosis and anisokaryosis, mitotic index, intratumoral necrosis, invasion of adjacent tissues, tumor location, local recurrence and metastasis were related to the diagnosis of benign (49/70) or malignant tumor (21/70). The Antoni A histological pattern was observed more frequently in benign tumors. The immunohistochemistry helped to diagnose PNST, and anti-vimentin and anti-protein S-100 showed the highest rates of immunostaining. Throughout statistical analysis of animals with tumor recurrence, it was found that the chance of an animal with a malignant peripheral nerve sheath tumor to develop recurrence is 4.61 times higher than in an animal that had a benign tumor.

RESUMO: Os neoplasmas cutâneos em cães apresentam elevada e relevante prevalência em todo o Brasil. Sendo assim, objetivou-se determinar a frequência e algumas características epidemiológicas dos neoplasmas cutâneos em cães diagnosticados no Laboratório de Patologia da Universidade Federal de Mato Grosso (LPV-UFMT), Cuiabá, entre os anos de 2007 a 2014. Foram revisados os protocolos de necropsias e biopsias do LPV-UFMT, de cães com neoplasmas cutâneos. Dados referentes à idade, sexo, raça dos cães afetados, localização anatômica, tamanho, diagnóstico histomorfológico e comportamento biológico foram coletados e analisados através de uma análise estatística descritiva. Adicionalmente o teste χ2, foi utilizado para associações entre comportamento biológico e tamanho da massa. Dos 3566 exames realizados, 656 (18,4%) foram diagnosticados como tumores cutâneos sendo cães adultos e idosos das raças Pit Bull, Boxer e Poodle os mais acometidos. Dentre os 11 padrões morfológicos mais diagnosticados o mastocitoma, carcinoma de células escamosas (CCE) e os tumores de origem vascular foram os mais frequentemente relatados. Em relação ao sítio anatômico, a cabeça foi a mais acometida. A maioria dos tumores benignos apresentaram menos de 1cm de diâmetro e os malignos de 3 a 5cm. O aumento de neoplasmas em adultos e idosos pode estar relacionado ao somatório de danos causados por agentes carcinogênicos e o comprometimento imunológico.

A interpretação das alterações encontradas na necropsia é uma etapa importante para o sucesso do diagnóstico final. Este trabalho tem como objetivo descrever e ilustrar os aspectos anatômicos, não lesões, artefatos, lesões sem significado clínico e alterações post mortem encontradas em suínos domésticos e selvagens. Além disso, também se recomenda técnicas de colheita de tecidos para o diagnóstico de doenças que acometem essa espécie. Os principais aspectos anatômicos e não lesões descritos são fímbrias linguais, quadrilátero esofágico, toro pilórico e demarcação do padrão lobular do fígado (sistema gastrintestinal); tonsilas do palato mole, tecido linfoide associado ao estômago, placas de Peyer do intestino delgado e dobras da margem do baço (sistema hematopoiético); mediastino proeminente do testículo e aréolas da placenta (sistema reprodutor); atelectasia pulmonar e apêndice decidual (feto); e glândulas carpais (sistema tegumentar). Os artefatos de eutanásia abordados são petéquias na superfície do pulmão e rim, falsa anemia por sangria, hemorragia subdural por concussão cerebral, pseudo-infartos do baço e aspecto cerebriforme do intestino delgado. As lesões de pouco significado clínico descritas são cistos renais, linfonodos com pigmento de ferro, papilomas e hemangiomas no escroto, ossos no mesentério e hiperemia da mucosa gástrica. As alterações post mortem comumente encontradas são livor mortis, músculos pálidos, pseudomelanose e líquido serosanguinolento nas cavidades torácica e abdominal em fetos.

ABSTRACT: Computerized microtomography is the gold standard examination for the evaluation of the three-dimensional bone structure. This experiment was developed to evaluate the structure and bone quality of Caiman yacare with metabolic bone disease using high resolution computerized microtomography (μCT). The animals were distributed into four groups: G1 - hyperphosphatemic diet with sun exposure deprivation (n=4), G2 - hyperphosphatemic diet with sun exposure (n=4), G3 - balanced diet with sun exposure deprivation (n=4), and G4 - balanced diet with exposure to sunlight (n=4). The parameters for the trabecular bone (Trabecular Number, Trabecular Thickness, Trabecular Separation, Bone Pattern Factor, Fractal Dimension, Euler Number, Structural Model Index, Degree of Anisotropy, Eigenvalues 1, 2 and 3, and Centroides X, Y and Z), and cortical bone (Number of Closed Pores, Volume of Closed Pores, Surface of Closed Pores, Closed Porosity, Volume of Open Pores, Open Porosity and Total Porosity). The overall results showed that the structure and bone quality of group G3 and G4 were better than those of groups G1 and G2, and that the diet factor influenced more than the sun exposure factor. The computerized microtomography allowed to evaluate the quality of the cortical and trabecular bones of the Pantanal alligator tibia with osteometabolic disease. The diet and sun exposure factors influenced individually the results of the μCT parameters between the groups, demonstrating the functional and structural complexity. Thus, these parameters can contribute to the interpretation of the mechanical behavior of bones and correlate them with the risk of lesions and fractures associated with osteometabolic diseases.

RESUMO: O granuloma leproide canino (GLC) é uma doença micobacteriana que cursa com lesão nodular, cutânea ou subcutânea, tipicamente auto limitante, decorrente de infecção pelo Mycobacterium. É uma doença dermatológica rara, usualmente relatada em países de clima tropical. O objetivo deste trabalho é caracterizar as alterações microscópicas e epidemiológicas de casos de GLC. Além disso, utilizar exames complementares para demonstração do Mycobacterium sp. na lesão analisada utilizando coloração de Ziehl-Neelsen, imuno-histoquímica e PCR para classificação e sequenciamento da espécie de Mycobacterium. Foram analisados 27 casos de GLC diagnosticados no período compreendido de 2005 a 2014 (21 exames histológicos e seis citológicos). A raça mais acometida foi Boxer (33,3%), seguida da Dachshund (11,1%). Foi frequente o acometimento de caninos de grande porte (64%) e de pelame curto (96%). Não foi possível estabelecer qualquer padrão de sazonalidade do GLC. As lesões se localizaram anatomicamente no pavilhão auricular na maioria dos casos (93%), constituindo-se de nódulos únicos ou múltiplos, ulcerados ou não. Em nenhum dos casos foi observado acometimento sistêmico. Lesões histológicas seguiram três padrões que variaram de nodulares a difusos, com infiltrado granulomatoso/piogranulomatoso com envolvimento de derme superficial e profunda. A observação de bacilos pela coloração de Ziehl-Neelsen confirmou o diagnóstico. Este teste demonstrou grande variação na quantidade de bacilos nas lesões, não relacionado estatisticamente ao tipo da lesão nem ao período evolutivo. A imuno-histoquímica foi positiva em 90% dos casos, e em alguns casos facilitou a identificação de bacilos, entretanto, em dois casos ocorreram resultados negativos mesmo havendo marcação pela coloração de Ziehl-Neelsen. Na técnica de PCR realizada em 18 amostras, 44% dos casos foram positivos, duas sequências inespecíficas, e demonstrou ainda, que Mycobacterium murphy foi responsável por 2 casos e Mycobacterium hodleri em um caso. Em outros três casos não se obteve 100% de semelhança entre o produto sequenciado e os demais Mycobacterium.

RESUMO: Foi realizado um levantamento nos arquivos do Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Mato Grosso (UFMT) das doenças de bovinos registradas entre os anos 2005 a 2014. Foram revisados 1124 casos. Destes, 27,6% foram amostras obtidas de necropsias realizadas por técnicos do LPV-UFMT e 72,3% foram amostras encaminhadas ao LPV-UFMT por veterinários de campo. Em 49,38% dos casos (555/1124) o diagnóstico da doença foi feito através da análise morfológica de lesões e/ou através de exames complementares. Raiva foi a principal causa de morte de bovinos neste estudo (7,82%). As doenças inflamatórias e parasitárias foram as mais prevalentes sendo diagnosticadas em 27,49% dos casos, seguida das doenças tóxicas e toxiinfecções com 9,78%. As demais categorias foram distribuídas em ordem decrescente em: neoplasmas e lesões tumoriformes (4%), doenças degenerativas (3,02%), distúrbios causados por agentes físicos (2,84%), distúrbios metabólicos e nutricionais (1,42%) e outras categorias (0,71%).

Abstract Background A Tonsil-Oral-Scrubbing (TOSc) method was developed to sample the sow’s oropharyngeal and tonsillar area without snaring and has shown comparable porcine reproductive and respiratory syndrome virus (PRRSV) RNA detection rates with tonsil scraping in infected sows. This study investigated the effect of specific TOSc collection factors on the PRRSV RT-rtPCR results (detection rates and Ct values). Those factors include whether the sow was snared or not snared at TOSc collection (“snared” vs. “not snared”); whether the sow was laying down or standing at collection (“laying down” vs. “standing”); and type of collectors used for TOSc collection (“TOSc prototype” vs. “Spiral-headed AI catheter (SHAC)”). Volume of fluid was compared between “snared” and “not snared” groups, and collection time was compared between “laying down” and “standing” groups as well. Results The effect for each factor was assessed in three independent studies following the same design: TOSc was collected twice from each studied sow, once with the baseline level for a factor (“not snared”, or “standing”, or “TOSc prototype”), and another time followed by the other level of the paired factor (“snared”, “laying down”, or “SHAC”, correspondingly). Results showed that “not snared” TOSc had numerically higher PRRSV RNA detection rate (60.7% vs. 52.5%, p = 0.11), significantly lower median Ct values (31.9 vs. 32.3, p

IntroductionCurrent common sample types for sows, such as serum and tonsil scraping, require snaring the animals, which can be labor-intensive and raise concerns regarding animal welfare. Obtaining oral fluids (OF) from individual sows in field conditions presents challenges, as not all sows readily respond to the rope method. The Tonsil-Oral-Scrubbing (TOSc) collector allows for the rapid retrieval of fluids from the sow’s oral and tonsillar areas without the need for snaring. Previous studies have reported comparable detection rates of porcine reproductive and respiratory syndrome virus (PRRSV) RNA between TOSc and tonsil scraping, with significantly higher positivity observed in TOSc compared to serum in acutely infected sows.MethodsGiven that PRRSV RNA detection rates can vary among different sample types and fluctuate over time, this field study aimed to compare PRRSV real-time reverse-transcription polymerase chain reaction (RT-rtPCR) positivity and cycle threshold (Ct) values between TOSc, serum, OF, and tonsil scraping at three time points following live-virus inoculation (LVI) in sows. This study was conducted within a breeding herd attempting to eliminate PRRSV following an outbreak. Four sample types were collected from each of the 61 conveniently selected sows at 30, 60, and 90 days post-LVI in the order of OF, TOSc, tonsil scraping, and serum, and subsequently tested for PRRSV RNA.ResultsThe results indicated that TOSc and tonsil scraping exhibited decreased PRRSV RNA detection rates over time, whereas the detection rates for OF and serum remained relatively stable. Moreover, the median Ct values for TOSc and tonsil scraping were numerically lower than those for OF and serum at all sampling points. Specifically, tonsil scraping demonstrated significantly higher PRRSV RNA positivity than the other three sample types. TOSc also exhibited significantly higher PRRSV RNA positivity than OF and serum at both 30 and 60 days post-LVI. By 90 days post-LVI, there was a significant difference in the PRRSV RNA detection rates between TOSc and tonsil scraping. However, no significant difference was observed between TOSc and OF or between TOSc and serum. According to the RT-rtPCR results, most PRRSV RNA-positive sows detected via TOSc and tonsil scraping turned negative by 90 days post-LVI, although a small proportion remained positive. Conversely, a small number of previously negative sows tested positive at 60 and 90 days post-LVI, indicating an intermittent mode of PRRSV RNA detection for both sample types.

Abstract Background Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific antemortem diagnostic tests, and the polymicrobial nature of swine diagnostic cases. The main objective of this retrospective study was to estimate temporal patterns of agent detection and disease diagnosis for five endemic bacteria that can cause systemic disease in porcine tissue specimens submitted to the Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) from 2017 to 2022. The study also explored the diagnostic value of specific tissue specimens for disease diagnosis, estimated the frequency of polymicrobial diagnosis, and evaluated the association between phase of pig production and disease diagnosis. Results S. suis and G. parasuis bronchopneumonia increased on average 6 and 4.3%, while S. suis endocarditis increased by 23% per year, respectively. M. hyorhinis and A. suis associated serositis increased yearly by 4.2 and 12.8%, respectively. A significant upward trend in M. hyorhinis arthritis cases was also observed. In contrast, M. hyosynoviae arthritis cases decreased by 33% average/year. Investigation into the diagnostic value of tissues showed that lungs were the most frequently submitted sample, However, the use of lung for systemic disease diagnosis requires caution due to the commensal nature of these agents in the respiratory system, compared to systemic sites that diagnosticians typically target. This study also explored associations between phase of production and specific diseases caused by each agent, showcasing the role of S. suis arthritis in suckling pigs, meningitis in early nursery and endocarditis in growing pigs, and the role of G. parasuis, A. suis, M. hyorhinis and M. hyosynoviae disease mainly in post-weaning phases. Finally, this study highlighted the high frequency of co-detection and -disease diagnosis with other infectious etiologies, such as PRRSV and IAV, demonstrating that to minimize the health impact of these endemic bacterial agents it is imperative to establish effective viral control programs. Conclusions Results from this retrospective study demonstrated significant increases in disease diagnosis for S. suis, G. parasuis, M. hyorhinis, and A. suis, and a significant decrease in detection and disease diagnosis of M. hyosynoviae. High frequencies of interactions between these endemic agents and with viral pathogens was also demonstrated. Consequently, improved control programs are needed to mitigate the adverse effect of these endemic bacterial agents on swine health and wellbeing. This includes improving diagnostic procedures, developing more effective vaccine products, fine-tuning antimicrobial approaches, and managing viral co-infections.

Aggregated diagnostic data collected over time from swine production systems is an important data source to investigate swine productivity and health, especially when combined with records concerning the pre-weaning and post-weaning phases of production. The combination of multiple data streams collected over the lifetime of the pigs is the essence of the whole-herd epidemiological investigation. This approach is particularly valuable for investigating the multifaceted and ever-changing factors contributing to wean-to-finish (W2F) swine mortality. The objective of this study was to use a retrospective dataset (“master table”) containing information on 1,742 groups of pigs marketed over time to identify the major risk factors associated with W2F mortality. The master table was built by combining historical breed-to-market performance and health data with disease diagnostic records (Dx Codes) from marketed groups of growing pigs. After building the master table, univariate analyses were conducted to screen for risk factors to be included in the initial multivariable model. After a stepwise backward model selection approach, 5 variables and 2 interactions remained in the final model. Notably, the diagnosis variable significantly associated with W2F mortality was porcine reproductive and respiratory syndrome virus (PRRSV). Closeouts with clinical signs suggestive of Salmonella spp. or Escherichia coli infection were also associated with higher W2F mortality. Source sow farm factors that remained significantly associated with W2F mortality were the sow farm PRRS status, average weaning age, and the average pre-weaning mortality. After testing for the possible interactions in the final model, two interactions were significantly associated with wean-to-finish pig mortality: (1) sow farm PRRS status and a laboratory diagnosis of PRRSV and (2) average weaning age and a laboratory diagnosis of PRRS. Closeouts originating from PRRS epidemic or PRRS negative sow farms, when diagnosed with PRRS in the growing phase, had the highest W2F mortality rates. Likewise, PRRS diagnosis in the growing phase was an important factor in mortality, regardless of the average weaning age of the closeouts. Overall, this study demonstrated the utility of a whole-herd approach when analyzing diagnostic information along with breeding-to-market productivity and health information, to measure the major risk factors associated with W2F mortality in specified time frames and pig populations.

Abstract Background Family oral fluids (FOF) sampling has been described as a sampling technique where a rope is exposed to sows and respective suckling litters and thereafter wrung to obtain fluids. PCR-based testing of FOF reveals presence of PRRS virus RNA only at the litter level, as opposed to conventional individual-animal-based sampling methods that demonstrate PRRSV RNA at the piglet level. The relationship between the PRRSV prevalence at the individual piglet level and at the litter level in a farrowing room has not been previously characterized. Using Monte Carlo simulations and data from a previous study, the relationship between the proportion of PRRSV-positive (viremic) pigs in the farrowing room, the proportion of litters in the farrowing room with at least one viremic pig, and the likely proportion of litters to be positive by a FOF RT-rtPCR test in a farrowing room was characterized, taking into account the spatial distribution (homogeneity) of viremic pigs within farrowing rooms. Results There was a linear relationship between piglet-level- and litter-level prevalence, where the latter was always larger than the former. When the piglet-level prevalence was 1%, 5%, 10%, 20%, and 50%, the true-litter level prevalence was 5.36%, 8.93%, 14.29%, 23.21%, and 53.57%, respectively. The corresponding apparent-litter prevalence by FOF was 2.06%, 6.48%, 11.25%, 21.60%, and 51.56%, respectively. Conclusion This study provides matching prevalence estimates to help guide sample size calculations. It also provides a framework to estimate the likely proportion of viremic pigs, given the PRRSV RT-rtPCR positivity rate of FOF samples submitted from a farrowing room.

Swine nursery mortality is one of the most important key performance indicators (KPIs) for commercial swine production systems and, for the purpose of this study, refers to the number of pigs that died during the first 60 days during the post-weaning phase (approximately 170-day period). Likewise, nursery mortality accounts for almost 50% of the mortality that occurs throughout the post-weaning phase. Despite being a metric concerning the post-weaning phase of production, previous studies have demonstrated that nursery mortality is highly correlated with the previous performance of the piglets in the pre-weaning phase and to stocking conditions at placement in nursery sites. However, there is no evidence of that predictive models are currently routinely utilized in the swine industry to predict the nursery performance of individual groups of pigs based on their previous performance in the pre-weaning phase. One obstacle to building such predictive models is that health and management data as well as production data for the pre and post-weaning phases are collected with separate record-keeping programs and stored in unconnected databases.Thus, the objective of this study was to measure and compare the performance of 5 forecasting models for predicting nursery mortality using a master table containing data collected from a single swine production system for 1,831 groups of pigs. An automated model was built to integrate information for 48 variables included in the master table that was previously disconnected within the production system. After the model and parameter tuning process, the model with the best overall prediction performance was the Support Vector Machine (SVM) in terms of Root Mean Squared Error (RMSE=0.3929), Mean Absolute Error (MAE=0.2956), and coefficient of determination (R2=0.7761). This study demonstrated the ability to use an integrated master table containing whole-herd information until the placement event of nursery groups to predict their downstream nursery mortality through the initial 60 days of the post-weaning phase.

IntroductionThe porcine reproductive and respiratory syndrome virus (PRRSV) continues to challenge swine production in the US and most parts of the world. Effective PRRSV surveillance in swine herds can be challenging, especially because the virus can persist and sustain a very low prevalence. Although weaning-age pigs are a strategic subpopulation in the surveillance of PRRSV in breeding herds, very few sample types have been validated and characterized for surveillance of this subpopulation. The objectives of this study, therefore, were to compare PRRSV RNA detection rates in serum, oral swabs (OS), nasal swabs (NS), ear-vein blood swabs (ES), and family oral fluids (FOF) obtained from weaning-age pigs and to assess the effect of litter-level pooling on the reverse transcription-quantitative polymerase chain reaction (RT-qPCR) detection of PRRSV RNA.MethodsThree eligible PRRSV-positive herds in the Midwestern USA were selected for this study. 666 pigs across 55 litters were sampled for serum, NS, ES, OS, and FOF. RT-qPCR tests were done on these samples individually and on the litter-level pools of the swabs. Litter-level pools of each swab sample type were made by combining equal volumes of each swab taken from the pigs within a litter.ResultsNinety-six piglets distributed across 22 litters were positive by PRRSV RT-qPCR on serum, 80 piglets distributed across 15 litters were positive on ES, 80 piglets distributed across 17 litters were positive on OS, and 72 piglets distributed across 14 litters were positive on NS. Cohen's kappa analyses showed near-perfect agreement between all paired ES, OS, NS, and serum comparisons (). The serum RT-qPCR cycle threshold values (Ct) strongly predicted PRRSV detection in swab samples. There was a ≥ 95% probability of PRRSV detection in ES-, OS-, and NS pools when the proportion of positive swab samples was ≥ 23%, ≥ 27%, and ≥ 26%, respectively.DiscussionES, NS, and OS can be used as surveillance samples for detecting PRRSV RNA by RT-qPCR in weaning-age pigs. The minimum number of piglets to be sampled by serum, ES, OS, and NS to be 95% confident of detecting ≥ 1 infected piglet when PRRSV prevalence is ≥ 10% is 30, 36, 36, and 40, respectively.

We evaluated an active participatory design for the regional surveillance of notifiable swine pathogens based on testing 10 samples collected by farm personnel in each participating farm. To evaluate the performance of the design, public domain software was used to simulate the introduction and spread of a pathogen among 17,521 farms in a geographic region of 1,615,246 km2. Using the simulated pathogen spread data, the probability of detecting ≥ 1 positive farms in the region was estimated as a function of the percent of participating farms (20%, 40%, 60%, 80%, 100%), farm-level detection probability (10%, 20%, 30%, 40%, 50%), and regional farm-level prevalence. At 0.1% prevalence (18 positive farms among 17,521 farms) and a farm-level detection probability of 30%, the participatory surveillance design achieved 67%, 90%, and 97% probability of detecting ≥ 1 positive farms in the region when producer participation was 20%, 40%, and 60%, respectively. The cost analysis assumed that 10 individual pig samples per farm would be pooled into 2 samples (5 pigs each) for testing. Depending on the specimen collected (serum or swab sample) and test format (nucleic acid or antibody detection), the cost per round of sampling ranged from EUR 0.017 to EUR 0.032 (USD 0.017 to USD 0.034) per pig in the region. Thus, the analysis suggested that an active regional participatory surveillance design could achieve detection at low prevalence and at a sustainable cost.

Classical swine fever (CSF) and foot-mouth disease (FMD) are both highly contagious disease and disruptive to commercial trades, but they are examples of foreign animal diseases that biosecurity-based compartmentalization could be used to support trade in free zones in response to an outbreak. This study aimed to evaluate biosecurity compliance to the Federal Normative Instruction #44 from December 4th, 2017 (BRAZIL, 2017) in commercial swine farms located in southern Brazil. A total of 604 swine farms from 10 commercial swine companies were sampled, from which 28.5% were breeding farms, 29.1% nursery, 32.8% finishing, 6.8% multipliers, and 2.8% farrow-to-finish. Cluster analyses revealed that farms with high compliance (n = 303, Cluster 1) performed 71% of the practices, moderate (n = 219, Cluster 2) 47%, and the low (n = 82, Cluster 3) 33%. A spatial logistic regression model estimated that biosecurity compliance was highest in only one of 10 commercial swine companies, and within a company, multipliers (when present) obtained the highest biosecurity compliance (p-value < 0.01). These results suggest that major improvements in biosecurity practices are needed in breeding herds, nursery, and grow-finish farms to be compliant to the Federal Instruction #44. Based on the combination of these analyses, only one commercial swine company was more suitable to establish compartments for CSF and FMD with minimal investments. Still, this study revealed that the majority of commercial swine companies needs to improve biosecurity practice protocols to then target compartmentalization.

Influenza A virus (IAV) is an endemic respiratory pathogen affecting swine worldwide and is a public health concern as a zoonotic pathogen. Veterinarians may respond to IAV infection in swine with varied approaches depending on their perception of its economic impact on human and animal health. This study considered three primary veterinary practice categories: swine exclusive veterinary practitioner, large animal practitioner, which corresponds to veterinarians that work predominantly with food animals including but not exclusively porcine, and mixed animal practitioner, which corresponds to veterinarians working with companion and food animals. This survey aimed to assess U.S. veterinarian perceptions, biosecurity practices, and control methods for IAV in swine. In this study, 54.5% (188/345) of the veterinarians that were targeted responded to all portions of the survey. The study results presented different perceptions regarding IAV among veterinarians in different types of veterinary practices and the current IAV mitigation practices implemented in swine farms based on strategic decisions. Collectively, this study also revealed the veterinarians' perceptions that IAV as a health problem in swine is increasing, IAV has a moderate economic impact, and there is a high level of concern regarding IAV circulating in swine. These findings highlight the need for IAV surveillance data, improved vaccine strategies, as well as important opportunities regarding methods of control and biosecurity. Additionally, results of this survey suggest biosecurity practices associated with the veterinarian's swine operations and prevention of zoonotic diseases can be strengthened through annual IAV vaccination of humans and support of sick leave policies for farm workers.

The performance of five forecasting models was investigated for predicting nursery mortality using the master table built for 3242 groups of pigs (~13 million animals) and 42 variables, which concerned the pre-weaning phase of production and conditions at placement in growing sites. After training and testing each model’s performance through cross-validation, the model with the best overall prediction results was the Support Vector Machine model in terms of Root Mean Squared Error (RMSE = 0.406), Mean Absolute Error (MAE = 0.284), and Coefficient of Determination (R2 = 0.731). Subsequently, the forecasting performance of the SVM model was tested on a new dataset containing 72 new groups, simulating ongoing and near real-time forecasting analysis. Despite a decrease in R2 values on the new dataset (R2 = 0.554), the model demonstrated high accuracy (77.78%) for predicting groups with high (>5%) or low (