ABSTRACT
For successful development and adoption of technology on dairy farms, farmers need to be included in the innovation process. However, the design of agricultural technologies usually takes a top-down approach with little involvement of end-users at the early stages. Living Labs offer a methodology that involve end-users throughout the development process and emphasize the importance of understanding users' needs. Currently, exploration of dairy farmers' technology needs has been limited to specific types of technology (e.g., smartphone apps) and adult cattle. The aim of this study was to use a Living Lab approach to identify dairy farmers' data and technology needs to improve herd health and inform innovation development. We conducted 18 focus groups with a total of 80 dairy farmers from Belgium, Ireland, the Netherlands, Norway, Sweden, and the United Kingdom. Data were analyzed using Template Analysis, and 6 themes were generated representing the fundamental needs of autonomy, comfort, competence, community and relatedness, purpose, and security. Farmers favored technologies that provided them with convenience, facilitated their knowledge and understanding of problems on farm, and allowed them to be self-reliant. Issues with data sharing and accessibility and usability of software were barriers to technology use. Furthermore, farmers were facing problems around recruitment and management of labor and needed ways to reduce stress. Controlling aspects of the barn environment, such as air quality, hygiene, and stocking density, were particular concerns in relation to youngstock management. Overall, the findings suggest that developers of farm technologies may want to include farmers in the design process to ensure a positive user experience and improve accessibility. The needs identified in this study can be used as a framework when designing farm technologies to strengthen need satisfaction and reduce any potential harm toward needs.
Subject(s)
Dairying , Farmers , Focus Groups , Cattle , Dairying/methods , Animals , IrelandABSTRACT
In the Surveillance Tool for Outcome-based Comparison of FREEdom from infection (STOC free) project (https://www.stocfree.eu), a data collection tool was constructed to facilitate standardised collection of input data, and a model was developed to allow a standardised and harmonised comparison of the outputs of different control programmes (CPs) for cattle diseases. The STOC free model can be used to evaluate the probability of freedom from infection for herds in CPs and to determine whether these CPs comply with the European Union's pre-defined output-based standards. Bovine viral diarrhoea virus (BVDV) was chosen as the case disease for this project because of the diversity in CPs in the six participating countries. Detailed BVDV CP and risk factor information was collected using the data collection tool. For inclusion of the data in the STOC free model, key aspects and default values were quantified. A Bayesian hidden Markov model was deemed appropriate, and a model was developed for BVDV CPs. The model was tested and validated using real BVDV CP data from partner countries, and corresponding computer code was made publicly available. The STOC free model focuses on herd-level data, although that animal-level data can be included after aggregation to herd level. The STOC free model is applicable to diseases that are endemic, given that it needs the presence of some infection to estimate parameters and enable convergence. In countries where infection-free status has been achieved, a scenario tree model could be a better suited tool. Further work is recommended to generalise the STOC free model to other diseases.
Dans le cadre du projet européen STOC free (Surveillance Tool for Outcome-based Comparison of FREEdom from infection, outil de surveillance permettant de comparer les probabilités d'absence d'infection sur la base des résultats, https://www.stocfree.eu), un outil de recueil des données a été construit pour faciliter une collecte normalisée des données d'entrée ; un modèle a également été élaboré pour permettre une comparaison normalisée et harmonisée des données sur les résultats des différents programmes de contrôle des maladies des bovins. Le modèle STOC free peut être utilisé pour évaluer la probabilité d'absence d'infection au sein des troupeaux dans le cadre des programmes de contrôle et déterminer si ces programmes sont conformes aux normes définies par l'Union européenne en termes de résultats attendus. L'infection par le virus de la diarrhée virale bovine a été choisie comme maladie d'étude pour ce projet en raison de la diversité des programmes de contrôle dans les six pays participants. Les informations relatives aux programmes de contrôle et aux facteurs de risque d'infection ont été recueillies à l'aide de l'outil de collecte des données. Les aspects clés et valeurs par défaut ont été quantifiés en vue d'être inclus dans le modèle STOC free. Un modèle de Markov caché dont les paramètres sont estimés par inférence bayésienne a été considéré comme le plus adapté et développé pour une application aux données issues des programmes de contrôle de la diarrhée virale bovine. Ce modèle a été testé et validé en utilisant des données réelles des programmes de contrôle du virus de la diarrhée virale bovine des pays participants ; le code informatique correspondant a été rendu public. Le modèle STOC free utilise des données au niveau des troupeaux, même si des données au niveau des animaux individuels peuvent être incluses une fois agrégées au niveau du troupeau. Le modèle STOC free s'applique aux maladies endémiques, puisqu'un certain niveau de présence de l'infection est nécessaire pour estimer les paramètres et permettre la convergence. Dans les pays ayant obtenu le statut indemne d'infection, un modèle du type arbre de scénario pourrait être un outil plus adapté. Des travaux supplémentaires sont recommandés pour généraliser le modèle STOC free à d'autres maladies.
Como parte del proyecto europeo STOC free (Surveillance Tool for Outcome-based Comparison of FREEdom from infection, herramienta de vigilancia para comparaciones por resultados respecto a la ausencia de infecciones, https://www.stocfree.eu), se confeccionó una herramienta de obtención de datos para facilitar la recogida normalizada de datos entrantes y se elaboró un modelo que posibilitara una comparación normalizada y armonizada de los resultados (datos salientes) de distintos programas de control de enfermedades bovinas. El modelo STOC free puede servir para calcular la probabilidad de ausencia de infección en los rebaños como parte de los programas de control y para determinar si estos programas se ajustan a las normas predefinidas de resultados de la Unión Europea. Como ejemplo de estudio para el proyecto se eligió el virus de la diarrea viral bovina (virus DVB) por la diversidad que presentaban los correspondientes programas de control de los seis países participantes. Empleando la herramienta de obtención de datos, se reunió información pormenorizada de los programas de control del virus DVB y los factores de riesgo. Para incluir los datos en el modelo STOC free, se cifraron unos aspectos clave y valores predeterminados Juzgando conveniente el empleo de un modelo oculto de Markov cuyos parámetros se estiman por inferencia bayesiana, se elaboró un modelo de esta índole aplicable a los programas de control del virus DVB. Para ensayar y validar el modelo se utilizaron datos reales de los programas de control del virus DVB de los países participantes, tras lo cual se hizo público el correspondiente código informático. El modelo STOC free trabaja con los datos por rebaño, aunque tras la agregación por rebaños pueden incluirse también datos por individuo. Para que este modelo sea aplicable a una enfermedad es preciso que esta sea endémica, pues el modelo requiere la presencia de cierto nivel de infección para calcular los parámetros y determinar convergencias. En aquellos países donde ya esté reconocida la ausencia de infección, sería más apropiado utilizar como herramienta un modelo de árbol de hipótesis. Los autores recomiendan ahondar en esta línea de trabajo para poder extender a otras enfermedades el uso del modelo STOC free.
Subject(s)
Bovine Virus Diarrhea-Mucosal Disease , Cattle Diseases , Diarrhea Viruses, Bovine Viral , Cattle , Animals , Bovine Virus Diarrhea-Mucosal Disease/epidemiology , Bovine Virus Diarrhea-Mucosal Disease/prevention & control , Bayes Theorem , Cattle Diseases/epidemiology , Cattle Diseases/prevention & control , Risk Factors , FreedomABSTRACT
Countries have implemented control programmes (CPs) for cattle diseases such as bovine viral diarrhoea virus (BVDV) that are tailored to each country-specific situation. Practical methods are needed to assess the output of these CPs in terms of the confidence of freedom from infection that is achieved. As part of the STOC free project, a Bayesian Hidden Markov model was developed, called STOC free model, to estimate the probability of infection at herd-level. In the current study, the STOC free model was applied to BVDV field data in four study regions, from CPs based on ear notch samples. The aim of this study was to estimate the probability of herd-level freedom from BVDV in regions that are not (yet) free. We additionally evaluated the sensitivity of the parameter estimates and predicted probabilities of freedom to the prior distributions for the different model parameters. First, default priors were used in the model to enable comparison of model outputs between study regions. Thereafter, country-specific priors based on expert opinion or historical data were used in the model, to study the influence of the priors on the results and to obtain country-specific estimates. The STOC free model calculates a posterior value for the model parameters (e.g. herd-level test sensitivity and specificity, probability of introduction of infection) and a predicted probability of infection. The probability of freedom from infection was computed as one minus the probability of infection. For dairy herds that were considered free from infection within their own CP, the predicted probabilities of freedom were very high for all study regions ranging from 0.98 to 1.00, regardless of the use of default or country-specific priors. The priors did have more influence on two of the model parameters, herd-level sensitivity and the probability of remaining infected, due to the low prevalence and incidence of BVDV in the study regions. The advantage of STOC free model compared to scenario tree modelling, the reference method, is that actual data from the CP can be used and estimates are easily updated when new data becomes available.
Subject(s)
Bovine Virus Diarrhea-Mucosal Disease , Cattle Diseases , Diarrhea Viruses, Bovine Viral , Animals , Bayes Theorem , Bovine Virus Diarrhea-Mucosal Disease/epidemiology , Bovine Virus Diarrhea-Mucosal Disease/prevention & control , Cattle , Cattle Diseases/epidemiology , FreedomABSTRACT
For endemic infections in cattle that are not regulated at the European Union level, such as bovine viral diarrhea virus (BVDV), European Member States have implemented control or eradication programs (CEP) tailored to their specific situations. Different methods are used to assign infection-free status in CEP; therefore, the confidence of freedom associated with the "free" status generated by different CEP are difficult to compare, creating problems for the safe trade of cattle between territories. Safe trade would be facilitated with an output-based framework that enables a transparent and standardized comparison of confidence of freedom for CEP across herds, regions, or countries. The current paper represents the first step toward development of such a framework by seeking to describe and qualitatively compare elements of CEP that contribute to confidence of freedom. For this work, BVDV was used as a case study. We qualitatively compared heterogeneous BVDV CEP in 6 European countries: Germany, France, Ireland, the Netherlands, Sweden, and Scotland. Information about BVDV CEP that were in place in 2017 and factors influencing the risk of introduction and transmission of BVDV (the context) were collected using an existing tool, with modifications to collect information about aspects of control and context. For the 6 participating countries, we ranked all individual elements of the CEP and their contexts that could influence the probability that cattle from a herd categorized as BVDV-free are truly free from infection. Many differences in the context and design of BVDV CEP were found. As examples, CEP were either mandatory or voluntary, resulting in variation in risks from neighboring herds, and risk factors such as cattle density and the number of imported cattle varied greatly between territories. Differences were also found in both testing protocols and definitions of freedom from disease. The observed heterogeneity in both the context and CEP design will create difficulties when comparing different CEP in terms of confidence of freedom from infection. These results highlight the need for a standardized practical methodology to objectively and quantitatively determine confidence of freedom resulting from different CEP around the world.
Subject(s)
Bovine Virus Diarrhea-Mucosal Disease/prevention & control , Diarrhea Viruses, Bovine Viral/physiology , Diarrhea/virology , Animals , Bovine Virus Diarrhea-Mucosal Disease/epidemiology , Bovine Virus Diarrhea-Mucosal Disease/virology , Cattle , Diarrhea/epidemiology , Diarrhea/prevention & control , Disease Eradication , Epidemiological Monitoring , Europe/epidemiology , Female , Risk FactorsABSTRACT
Based on Swedish legislation, all herds where Salmonella of any serotype is detected are put under restrictions, and measures aiming at eradication are required. Costs for sampling and control have increased in recent years and the aim of this study was to investigate the efficiency of different sampling strategies. We also compiled test results from recent surveillance activities and used these to complement and compare with calculated results. Sensitivities and specificities at group and herd level were calculated for different test strategies. A scenario-tree modeling approach was used to account for the hierarchy of animals within herds, and different relative risk of salmonella in different age groups. Negative and positive predictive values (NPV and PPV), and probability of freedom from Salmonella were calculated to compare the added value of different sampling strategies. Results showed that more fecal samples than serological samples per group are needed to reach a group sensitivity >0.50. This also means that serological testing leads to a higher NPV. For example, with 10 negative test-results from a group of 25 animals in a herd with a suspicion of Salmonella, the NPV based on serology was 0.75 and based on culture was 0.56. For the PPV, testing based on culture from fecal sampling was superior, as specificity of such testing was close to perfect. By changing the threshold for considering a group positive, from 1 test-positive animal to 2, the PPV of serological results could be increased without substantial loss in NPV. The herd sensitivity based on (1) bulk milk sampling, (2) fecal sampling of all animals, and (3) bulk milk sampling and individual sera from 20 animals within each age group was 0.53, 0.88, and 0.95, respectively. In low-prevalence regions, this sensitivity was enough to verify a high probability of freedom (>0.99), as the probability of infection in such Swedish regions has been shown to be 0.01. For herds with a higher prior probability of infection, repeated sampling (2-9 sampling occasions) was needed to reach the same level of confidence. Analysis of surveillance data indicated that boot swabs can be used to replace the standard fecal sampling presently used in Sweden. It was also confirmed that the individual specificity of the tests used for serological testing of Swedish calves is high (0.99). The results can form a basis for fit-for-purpose testing strategies (e.g., surveillance or prepurchase testing).
Subject(s)
Cattle Diseases/prevention & control , Milk/metabolism , Salmonella Infections, Animal/prevention & control , Salmonella/immunology , Animals , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/microbiology , Epidemiological Monitoring , Feces/microbiology , Female , Prevalence , Salmonella/isolation & purification , Salmonella Infections, Animal/epidemiology , Salmonella Infections, Animal/microbiology , Sensitivity and Specificity , Serogroup , Sweden/epidemiologyABSTRACT
A preventive herd health approach will most likely reduce incidences of clinical and subclinical disease. Swedish veterinary organizations offer specific veterinary herd health management (HHM) programs, but these services are not used to a large extent. The aim of this study was to investigate dairy farmers' experience of HHM and the conditions for collaboration with veterinarians in HHM. Six focus group discussions were conducted in March 2015 in West Sweden. In total, 33 dairy farmers participated. The recordings were transcribed and coded using thematic analysis, and the transcripts were reviewed to identify potential factors indicating barriers for farmers to engage a veterinarian in HHM. The participants reported HHM to be important, but they had difficulty defining the actions included in the concept. They described a wide range of their work duties as preventive. The farmers' list of potential contributions by the veterinarians in HHM was strikingly short compared to the considerable number of preventive measures they performed themselves. Four main obstacles for farmers and farm managers to engage a veterinarian in HHM on their farm were identified in the analysis: "costs", "veterinary knowledge, skills, and organization", "farmer attitudes", and "veterinarian-farmer relationships". Costs were proposed as the main reason against engaging a veterinarian in HHM and included a high veterinary bill, low cost-benefit of veterinary services, and high costs to implement advice. Poor veterinary competence in HHM and poor knowledge about effective measures, practical farming, and farm economics were other important obstacles. Veterinarians were perceived to insufficiently describe their services and their benefits, and several participants felt they had never been offered veterinary HHM. Although veterinary HHM may be initiated by the farmer, the participants expected the veterinarian to have special responsibility for the initiation. A firm trust between farmer, staff, and veterinarian was considered crucial for veterinary HHM, but such trust takes a long time to build and can easily be disrupted by, for example, a veterinarian's poor communication skills or lack of time. Our findings suggest that Swedish dairy farmers and herd managers find disease prevention important and that they perform a wide range of tasks to prevent disease in their animals. However, they do not see what role the veterinarian can play, and veterinarians were mainly associated with treating unhealthy cows. In order to increase the use of veterinary HHM programs the services and potential benefits of such programs need to be communicated more proactively.
Subject(s)
Cattle Diseases/prevention & control , Dairying/methods , Disease Management , Farmers/psychology , Animals , Cattle , Farms , Female , Sweden , VeterinariansABSTRACT
Mastitis is one of the most costly diseases in dairy cows worldwide. Increased somatic cell count (SCC) is an indication of mastitis, often subclinical, which implies bacterial infection without clinical signs of inflammation. The aim was to investigate the occurrence of elevated udder SCC (defined as ≥200,000 cells/mL) over the lactation period, and before and after the dry period, for cows of different parity. The aim was also to analyze the association between prevalence and incidence of increased udder SCC and information on cow and herd level, such as breed and milking system type. Data were extracted from the Swedish Official Milk Recording Scheme between January 1, 2008, and December 31, 2011, including all herds with a yearly average of >60 cows. The data include descriptive information on herd and cow level and the results from the systematic test milking. The data included the following: for 2009, 239,182 cows in 1,633 herds; for 2010, 251,852 cows in 1,680 herds; and for 2011, 247,746 cows in 1,596 herds. The results show a peak in elevated udder SCC during the late summer season and that the highest proportion of cases occurs during the first lactation month; the latter was most prominent for primiparous cows. Forty-seven percent of all cows with elevated SCC recovered during dry period (went from high to low SCC), whereas 34% of all cows with low SCC before the dry period had an elevated SCC at first testing after calving. For first lactation cows, 19% had an elevated SCC at first test milking. When the outcomes for the 3 consecutive years were reanalyzed, it was confirmed that the effect of fixed factors such as breed, milk yield, and parity did not change over time, whereas the effect of milking system type did. For the incidence of becoming a new case and the prevalence of cows with elevated udder SCC, automatic milking system (AMS) was associated with reduced SCC in 2009 but associated with increased SCC in 2011. Regarding the proportion of new cases of elevated SCC per cow and year, AMS appeared to be a risk factor for all 3 yr, but the effect decreased over time. The shift for AMS from protective to risk factor regarding incidence of new cases and number of recordings with elevated SCC might reflect a change of the AMS population over these years. The findings indicate the need for appropriate udder health management customized to the system.
Subject(s)
Dairying/methods , Mammary Glands, Animal/pathology , Mastitis, Bovine/pathology , Milk/cytology , Animals , Cattle , Cell Count/veterinary , Female , Lactation , Mastitis, Bovine/epidemiology , Milk/metabolism , Pregnancy , Sweden/epidemiologyABSTRACT
Determining welfare status in a population is the first step in efforts to improve welfare. The primary objective of this study was to explore a new epidemiological approach for analysis of data from official competent authorities that pertain to compliance with animal welfare legislation. We reviewed data already routinely collected as part of Swedish official animal welfare inspections for 2010-13, using a checklist containing 45 checkpoints (CPs). These covered animal-, resource- and management-based measures of equine welfare. The animal-based CPs were measures that directly related to the animal and included social contact, body condition, hoof condition and cleanliness. Non-compliance with one or more of the animal-based CPs was used as a binary outcome of poor equine welfare; 95% confidence intervals (CI) were estimated using the exact binomial distribution. Associations were determined using multivariable logistic regression, adjusting for clustering on premises. Resource- and management-based CPs (model inputs) were reduced by principal component analysis. Other input factors included premises characteristics (e.g. size, location) and inspection characteristics (e.g. type of inspection). There were 30 053 premises with horses from 21 counties registered by the Swedish Board of Agriculture. In total 13 321 inspections of premises were conducted at 28.4% (n=8532) of all registered premises. For random inspections, the premises-prevalence of poor equine welfare was 9.5% (95% CI 7.5, 11.9). Factors associated with poor equine welfare were non-compliance with requirements for supervision, care or feeding of horses, facility design, personnel, stable hygiene, pasture and exercise area maintenance, as well as the owner not being notified of the inspection, a previous complaint or deficiency, spring compared with autumn, and not operating as a professional equine business. Horses at premises compliant with stabling and shelter requirements had significantly better welfare if they also complied with documentation requirements. We present a novel approach for analysis of equine welfare data from regulatory inspections by the official competent authorities, and propose on-going analyses and benchmarking of trends in animal-based measures over time. We also suggest how such a database could be further improved to facilitate future epidemiological analyses of risk factors associated with poor equine welfare. The study has implications for other competent authorities and researchers collaborating in the area of animal welfare epidemiology.
Subject(s)
Animal Husbandry/standards , Animal Welfare/statistics & numerical data , Horses/physiology , Animal Husbandry/legislation & jurisprudence , Animal Welfare/legislation & jurisprudence , Animals , Hygiene , Logistic Models , Prevalence , Risk Factors , Sweden/epidemiologyABSTRACT
Real-time PCR analysis of milk samples is a fast method to identify intramammary infections (IMI) in dairy cows, and has the potential to be used for routine analysis of test milking composite milk samples. However, the results of the PCR analysis can be difficult to interpret. The objective of this study was to compare the sensitivity (Se) and specificity (Sp) of PCR analysis of composite milk samples, and conventional bacteriological culturing (BC) of quarter milk samples, when used to identify cows with IMI. The comparisons were performed for IMI with four common udder pathogens; Staphylococcus aureus (S aureus), Streptococcus dysgalactiae (Str dysgalactiae), Str uberis and coagulase negative staphylococci (CoNS). The Se and Sp of real-time PCR (SePCR; SpPCR) and BC (SeBC; SpBC) was simultaneously estimated using latent class analysis (LCA), studying one pathogen at the time. Milk samples from 970 dairy cows from 25 herds were included. Aseptically collected quarter milk samples taken at the day before test milking (TM), at the day of TM, and at the day after TM, were analyzed using BC. Non-aseptically collected composite milk samples taken at the day of TM were analyzed using PCR. Moreover, the composite milk somatic cell count (SCC) was recorded and summarized by diagnostic test and bacterial finding. LCA was first performed using only test results from samples taken at the day of TM, but in a second analysis BC results from the three consecutive samplings, interpreted in parallel, were included. The SePCR was significantly higher than the SeBC for S aureus, Str dysgalactiae and CoNS in the first analysis, but only for CoNS in the second analysis. The SpPCR was significantly lower than the SpBC for Str dysgalactiae and CoNS. In conclusion, using PCR analysis of composite milk samples, as a diagnostic tool for identifying cows with IMI increased the Se for all the pathogens investigated (although not always significantly), while Sp in general remained on a similar level, compared to BC of quarter milk samples. The use of repeated quarter milk sampling improved the SeBC, making the results of PCR analysis and BC more similar. However, the SCC of cows with IMI according to BC was higher than for cows with IMI according to PCR, suggesting that some of the cows with IMI according to PCR did not have an active inflammation. Hence, extra caution is needed when decisions about treatment of IMI are based on PCR.
Subject(s)
Mastitis, Bovine/epidemiology , Milk/microbiology , Real-Time Polymerase Chain Reaction/veterinary , Staphylococcal Infections/veterinary , Streptococcal Infections/veterinary , Animals , Bayes Theorem , Cattle , Female , Mastitis, Bovine/diagnosis , Mastitis, Bovine/microbiology , Sensitivity and Specificity , Staphylococcal Infections/diagnosis , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Staphylococcus/classification , Staphylococcus/genetics , Staphylococcus/isolation & purification , Streptococcal Infections/diagnosis , Streptococcal Infections/epidemiology , Streptococcal Infections/microbiology , Streptococcus/classification , Streptococcus/genetics , Streptococcus/isolation & purification , Sweden/epidemiologyABSTRACT
Ruminants are considered the main reservoir for transmission of Coxiella burnetii (Cb) to humans. The implementation of effective control measures against Cb in ruminants requires knowledge about potential risk factors. The objectives of this study were (i) to describe the spatial distribution of Q fever-infected dairy cattle herds in Sweden, (ii) to quantify the respective contributions of wind and animal movements on the risk of infection, while accounting for other sources of variation, and (iii) to investigate the possible protective effect of precipitation. A total of 1537 bulk milk samples were collected and tested for presence of Cb antibodies. The prevalence of test-positive herds was higher in the south of Sweden. For herds located in areas with high wind speed, open landscape, high animal densities and high temperature, the risk of being infected reached very high values. Because these factors are difficult to control, vaccination could be an appropriate control measure in these areas. Finally, the cumulated precipitation over 1 year was identified as a protective factor.
Subject(s)
Antibodies, Bacterial/immunology , Coxiella burnetii/immunology , Milk/immunology , Q Fever/veterinary , Rain , Wind , Animals , Cattle , Cattle Diseases/epidemiology , Enzyme-Linked Immunosorbent Assay/veterinary , Prevalence , Protective Factors , Q Fever/epidemiology , Risk Factors , Seroepidemiologic Studies , Sweden/epidemiology , WeatherABSTRACT
Extensive and rapid spread of Schmallenberg virus (SBV) in Sweden was detected by consecutive serological bulk milk surveys conducted before and after the vector season of 2012. Whereas <0.2% of cattle herds tested positive in a first survey in spring 2012, SBV-specific antibodies were detected in almost 75% of 723 bulk milk samples randomly collected all over the country 6 months later, beyond the 65th northern latitude, and with an observed spatial distribution suggesting multiple introductions of the virus. Circulation of virus was later confirmed by the detection of SBV in malformed lambs and calves starting from November 2012 and January 2013, respectively. These observations suggest SBV circulation starting from July 2012, with a peak in transmission between August and October. A local heterogeneity of within-herd seroprevalence was found, indicating that SBV-naïve animals remain also in highly infected areas enabling the re-emergence of the infection in the coming vector season.
Subject(s)
Bunyaviridae Infections/epidemiology , Bunyaviridae Infections/veterinary , Cattle Diseases/virology , Orthobunyavirus/isolation & purification , Sheep Diseases/virology , Animals , Bunyaviridae Infections/virology , Cattle , Geography, Medical , Milk/virology , Orthobunyavirus/immunology , Seasons , Seroepidemiologic Studies , Sheep , SwedenABSTRACT
Toxoplasma gondii is a zoonotic protozoan parasite, infecting a wide range of warm-blooded animals. The Swedish wild boar population is expanding and increased hunting provides its meat to a growing group of consumers. We performed a spatio-temporal investigation of T. gondii seroprevalence in Swedish wild boars. An ELISA was set up and evaluated against a commercial direct agglutination test, using Bayesian latent class analysis. The ELISA sensitivity and specificity were estimated to 79% and 85%, respectively. Of 1327 serum samples, 50% were positive. Thirty-four per cent of young wild boars and 55% of adults were positive (P < 0.001). The total seroprevalence ranged from 72% in 2005 to 38% in 2011 (P < 0.001), suggesting a declining trend. The highest seroprevalence, 65%, was recorded in South Sweden. In other regions it varied from 29% in Stockholm to 46% in East Middle Sweden.
Subject(s)
Antibodies, Protozoan/blood , Swine Diseases/epidemiology , Swine Diseases/immunology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/epidemiology , Toxoplasmosis, Animal/immunology , Age Factors , Agglutination Tests/veterinary , Animals , Enzyme-Linked Immunosorbent Assay/veterinary , Geography , Meat/parasitology , Prevalence , Seasons , Seroepidemiologic Studies , Sweden/epidemiology , Swine , Swine Diseases/parasitology , Toxoplasma/immunology , Toxoplasmosis, Animal/parasitologyABSTRACT
The aim of this retrospective single-cohort study was to investigate if a rapid change in feeding, management, or housing or an increasing incidence of claw diseases or udder health problems is associated with decreased reproductive performance. Data on individual cows and herds were retrieved from the Swedish official milk recording system and questionnaire data on feeding system was obtained from the regional dairy associations. In total, 63,561 cows in 759 herds were included in the study. The associations between the probability of pregnancy at first insemination and number of inseminations per animal submitted for artificial insemination and potential predictor variables were investigated using a logistic regression model and a Poisson regression model, respectively. The results indicated that cows with severe claw lesions or an increasing somatic cell count after calving had a lower probability of pregnancy at first insemination and had a higher number of inseminations per animal submitted for artificial insemination than healthy cows. Variables representing a change in housing, production system, or milking system within the period from 6 mo before calving until establishment of a new pregnancy were significantly associated with decreased reproductive performance. No differences in fertility were observed between cows milked in an automatic milking system compared with cows milked conventionally. The results indicate that a change of system, rather than the actual type of milking or housing system negatively affects reproductive performance. Special attention should therefore be paid to the fertility of cows when the herd management is changing. It is also important to prevent claw lesions and increasing cell counts after calving to avoid a decrease in reproductive performance.
Subject(s)
Foot Diseases/veterinary , Hoof and Claw/pathology , Infertility, Female/veterinary , Insemination, Artificial/veterinary , Animals , Cattle , Cell Count/veterinary , Dairying , Female , Fertility , Infertility, Female/epidemiology , Infertility, Female/therapy , Insemination, Artificial/statistics & numerical data , Lactation , Logistic Models , Mammary Glands, Animal/physiology , Milk/metabolism , Pregnancy , Reproduction , Retrospective StudiesABSTRACT
Sweden experienced its first outbreak of bluetongue virus (BTV) infection beginning in September 2008. Mandatory vaccination with an inactivated vaccine (BTVPUR Alsap8; Merial, Lyon, France) began 2 days after bluetongue was confirmed in the country. The aim of this study was to investigate whether the goal of 80% seroconversion by the susceptible population within the vaccination area was met during the initial phase of the Swedish vaccination campaign and whether there were discrepancies between subpopulations. Milk or blood samples were collected from 274 cattle randomly selected from the vaccinated population. Blood samples were also collected from ten ewes on each of 28 randomly selected vaccinated herds. The vaccination campaign in Sweden may be regarded as successful, as measured by apparent seroprevalence in the vaccinated population. The overall apparent seroprevalence was 77%, and in cattle, which constituted the majority of the susceptible population, the apparent seroprevalence was 82%. Factors that influenced the titres after vaccination were as follows: (i) the time span between vaccination and sampling and (ii) the age of the animals.
Subject(s)
Antibodies, Viral/analysis , Bluetongue virus/immunology , Bluetongue/prevention & control , Cattle/immunology , Mass Vaccination/veterinary , Sheep/immunology , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Bluetongue/epidemiology , Cattle Diseases/epidemiology , Cattle Diseases/prevention & control , Female , Male , Milk/immunology , Seroepidemiologic Studies , Sweden/epidemiology , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunology , Viral Vaccines/administration & dosageABSTRACT
Negative energy balance is a known risk factor for decreased fertility in dairy cows. This study evaluated the accuracy of plasma concentrations of nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHBA), and insulin-like growth factor 1 (IGF-1)-factors related to negative energy balance-in predicting decreased fertility. One plasma sample per cow was collected from 480 cows in 12 herds during the period from d 4 to 21 in milk and analyzed for NEFA, BHBA, and IGF-1. For each cow, data on breed, parity, calving date, gynecological examinations, and insemination dates were obtained. Milk samples from 241 cows in 7 of the participating herds were analyzed for progesterone concentration to define the first day of luteal activity. The diagnostic sensitivity (Se) and specificity (Sp) at different cut-off concentrations of NEFA, BHBA, or IGF-1 were calculated and related to individual cow fertility status, measured as anestrus (ANEST), delayed first artificial insemination (DFAI), or delayed conception. Positive and negative predictive values (PV+; PV-) were calculated considering different levels of (within-herd) prevalence. Strata (i.e., subgroup)-specific Se and Sp and associations between test results and fertility parameters were investigated using logistic regression. The NEFA and BHBA tests for ANEST and DFAI had the highest combined Se and Sp and were thus evaluated further. Cut-off values with Sp around 80% were used in this step to provide a reasonable number of test-positive cows, representing a practical situation. This corresponded to a cut-off value for the NEFA test of 400 µEq/L (Se 0.27-0.45) and for the BHBA test of 1.8mM (Se 0.15-0.30) across all cows included in the study. The estimated Sp was generally higher than the original 80%, but the corresponding Se was further decreased when the test was used in heifers compared with older cows. The true prevalence of ANEST in the study population was 27%, which gave a PV+ of 0.36 to 0.45 and a PV- of 0.76 to 0.79. With 35% true prevalence of DFAI, PV+ was 0.29 to 0.38 and PV- was 0.64 to 0.66. Thus, overall test performance was low when metabolic indicators measured as single values in early lactation were used to predict fertility in dairy cows, but accuracy was influenced by cow-level factors such as parity. The prevalence of the target condition (in this case, decreased fertility) also influences test usefulness and should be considered when planning test systems and interpreting test results.
Subject(s)
Cattle/physiology , Fertility/physiology , 3-Hydroxybutyric Acid/blood , Anestrus/blood , Anestrus/metabolism , Anestrus/physiology , Animals , Biomarkers/blood , Cattle/blood , Cattle/metabolism , Fatty Acids, Nonesterified/blood , Female , Insulin-Like Growth Factor I/analysis , Milk/chemistry , Progesterone/analysis , Sensitivity and SpecificityABSTRACT
The objective of this field study was to evaluate the effect of supplemental feeding with glycerol or propylene glycol to dairy cows in early lactation on metabolic status, body condition and milk yield. In total, 673 newly calved cows from 12 commercial Swedish dairy herds were randomized to daily supplementation with 450 g of glycerol (GLY), 300 g of propylene glycol (PG), or nothing (control, CON). Supplements were fed twice daily from 0 to 21 d in milk (DIM) as a top dress on concentrates. For each cow, data on parity, breed, calving date, monthly test-day milk yield, and cases of diseases were collected. Blood samples were taken at approximately 2, 5, and 8 wk postpartum (pp) and analyzed for glucose, ß-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), and insulin. Samples taken within 3 wk pp were also analyzed for insulin-like growth factor 1 (IGF-1). Measurements of body condition score (BCS) and heart girth (HG) were obtained at approximately 2 and 5 wk pp and at time of first insemination. The effects of supplemental feeding with GLY or PG on the plasma concentrations of glucose, NEFA, BHBA, insulin, and IGF-1, and BCS, HG, and occurrence of disease were analyzed. No differences in BCS or HG or in plasma concentrations of glucose, BHBA, NEFA, or IGF-1 were found between the control group and any of the treatment groups. Cows in the GLY group had lower plasma insulin concentrations during DIM 0 to 63 compared with group CON, but no difference in insulin was found between the PG group and the CON group. Cows supplemented with GLY had a higher milk yield (kg of milk and kg of energy-corrected milk) during the first 90 DIM. Cows in the PG group tended to yield more milk during the same period. No differences in the occurrence of diseases were seen between the groups. In conclusion, supplementation with GLY in early lactation did increase milk yield without a subsequent decrease of metabolic status, and supplementation with PG tended to do the same.
Subject(s)
Dietary Supplements , Glycerol/pharmacology , Lactation/drug effects , Propylene Glycol/pharmacology , 3-Hydroxybutyric Acid/blood , Animals , Blood Glucose/analysis , Cattle/metabolism , Fatty Acids, Nonesterified/blood , Female , Insulin/blood , Insulin-Like Growth Factor I/analysis , Milk/metabolismABSTRACT
The aim of this field study was to evaluate the effect of supplemental feeding with glycerol (GLY) or propylene glycol (PG) during early lactation on the fertility of Swedish dairy cows. Within 17 commercial dairy herds, 798 cows were randomized to three groups that were daily fed supplements with 450 g GLY, 300 g PG or nothing (control, C). The supplements were given twice daily during 0-21 days in milk as a top dress on concentrates. Data on calving date, insemination dates, gynaecological examinations, as well as breed, parity and monthly milk yield were collected. From a subset of 308 cows in seven herds, milk samples for progesterone analysis were taken twice weekly and used to determine the time for onset of luteal activity. The effects of supplements on the intervals from calving to first luteal activity (FLA), first AI (FAI) and conception (CON), respectively, were analysed using semi-parametric survival models (Cox proportional hazards models) controlling for the effect of parity, breed, calving season, milk yield and the clustering effect of herd. There was no difference in time to FLA between the cows in group C and in group GLY or PG. No differences in time to FAI or in time to CON were found between cows in group PG and group C. However, cows in the GLY group tended to get their FAI later compared with cows in the control group but without at subsequent delaying of time to CON.
Subject(s)
Cattle/physiology , Dietary Supplements , Fertility/physiology , Glycerol/pharmacology , Lactation/drug effects , Propylene Glycol/pharmacology , Animal Feed/analysis , Animals , Dairying , Diet/veterinary , Female , Lactation/physiology , Pregnancy , SwedenABSTRACT
On-farm biosecurity is important for preventing the spread of several contagious animal diseases. In this study, biosecurity routines among Swedish farmers with livestock (cattle, pigs, sheep or goats) were examined through questionnaires posted by mail. Moreover, the use of protective clothing among professionals visiting farms, such as animal transporters and veterinarians, were investigated through assessments made by the farmers. Questionnaires were completed, partly or fully, by 518 farmers (overall response rate 34%). Possible associations between biosecurity routines and livestock species, geographic location and herd size were analysed. Large variations in biosecurity routines were found, both within and between groups, and some farms appeared to have a relatively high level of biosecurity. However, <40% of the farmers reported that they provide protective clothing for visitors, and 50% of farmers buying live animals introduced these directly into the herd without prior isolation. In general, a higher level of biosecurity was reported by farmers with herds with only pigs, when compared to farmers with cattle, sheep/goats or mixed species. A higher level of biosecurity was also reported by larger farms compared to hobby farms. Inconsistent biosecurity routines were reported, which was interpreted as a lack of knowledge of how different infections can spread and how this can be prevented. Furthermore, some replies indicated that the farmers perceived the risk of introduction of disease as low. According to the farmers' assessments, the use of protective clothing among professionals visiting farms varied considerably, both among different professions and within the same profession. On average, veterinarians and artificial insemination (AI) technicians got high scores in this assessment, while salesmen, repairmen and animal transporters were reported to seldom use protective clothing. Based on the findings, there is room for improvement of on-farm biosecurity. There is also a need to further investigate the motivators and constraints for altered routines among both Swedish livestock farmers and professionals visiting farms.
Subject(s)
Animal Diseases/prevention & control , Animal Husbandry/standards , Livestock , Agriculture , Animal Diseases/epidemiology , Animal Technicians , Animals , Data Collection , Surveys and Questionnaires , Sweden/epidemiology , VeterinariansABSTRACT
Herd, within-herd and animal prevalences for Neospora caninum in beef and dairy cattle were compared between four countries. In randomly selected herds from regions of Germany, The Netherlands, Spain and Sweden that were representative for the cattle production of these countries, all animals > or = 2 years were examined serologically by enzyme-linked immunosorbent assays (ELISAs) with high test specificity (> 98.0%). In a previous study, the ELISAs had been validated against each other. Single reacting animals within a herd were confirmed by immunobloting. At the time of sampling, animal (age, breed, herdtype, sex, lactation stage) and herd data (region) were collected. Considerable differences in N. caninum herd, within-herd, and overall animal prevalence estimations were observed between countries, regions, herdtype, age categories and breeds. Herd prevalences, based on confirmation of single reactors, for dairy herds were estimated to be 16% (95%CI: 10-24%) in Sweden, 49% (95%CI: 39-59%) in Germany, 63% (95%CI: 57-69%) in Spain and 76% (95%CI: 67-84%) in The Netherlands and for beef herds 41% (95%CI: 31-50%) in Germany, 46% (95%CI: 41-51%) in Spain and 61% (95%CI: 50-72%) in The Netherlands. No beef herds were examined in Sweden. The lowest animal true prevalence was estimated in dairy cattle in Sweden (0.5% (95%CI: 0.1-0.8%)) while the highest animal true prevalence was estimated for dairy cattle in Spain (16.2% (95%CI: 14.9-17.5%)). Within-herd prevalences varied greatly, with very few farms in Sweden having more than 10% seropositive animals while in Spain more than 10% of the herds had within-herd prevalences between 50 and 100%. Seropositivity was significantly associated with herdtype (beef versus dairy), age, breed and region within countries. The results of this supranational comparative study showed that the importance of N. caninum infection varied greatly within in Europe. Estimates of prevalence can be used to calculate the economic impact of N. caninum infection as well as to evaluate the effect of prevention and control strategies over time.
Subject(s)
Antibodies, Protozoan/blood , Cattle Diseases/epidemiology , Coccidiosis/veterinary , Neospora/immunology , Age Factors , Animals , Breeding , Cattle , Coccidiosis/epidemiology , Cross-Sectional Studies , Dairying , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Germany/epidemiology , Immunoblotting/veterinary , Male , Netherlands/epidemiology , Sensitivity and Specificity , Seroepidemiologic Studies , Spain/epidemiology , Sweden/epidemiologyABSTRACT
Various existing serological tests were compared with a standard panel of 523 sera in a multicentred study across Europe. Well characterised sera from animals that were experimentally or naturally infected with Neospora caninum as well as sera from cattle deemed uninfected with N. caninum were provided by the participants of the study and analysed in several commercial (CHEKIT Dr. Bommeli/Intervet, CIVTEST BOVIS NEOSPORA Hipra, Cypress Diagnostics C.V., Herd Check IDEXX, Mastazyme MAST Diagnostics, P38-ELISA Animal Welfare and Food Safety GmbH (AFOSA)) as well as in-house assays (five ELISAs and one IFAT). Most tests showed a high level of agreement in the interpretation of the test results (positive or negative). A further distinct increase in agreement between tests was obtained after the application of standardised cut-offs offered by a two-graph receiver operating characteristic analysis. This procedure allows a standardised interpretation of results obtained with different tests used in independent, parallel seroepidemiological studies.