Risk factors for stillbirths and mortality during the first 24h of life on dairy farms in Hokkaido, Japan 2005-2009.

This was a retrospective cohort study using data from the insurance scheme provided by the Japanese Mutual Aid Association (NOSAI). The population of interest comprised all cattle born on NOSAI-client farms in the Japanese prefecture of Hokkaido, Japan for the period 1 April 2005-31 March 2009. The outcome of interest was whether or not at least one calf was stillborn, had died during delivery or died during the first 24 hours of life for a given calving event, termed first 24h mortality risk. A mixed-effects logistic regression model was developed to identify explanatory variables associated with first 24h mortality risk. The final data set comprised details of 1,281,737 calving events on a total of 5172 dairy herds from 19 NOSAI branches located throughout the prefecture of Hokkaido. Throughout the study period 7.68 (95% CI 7.64-7.73) of every 100 calving events had at least one calf that was either stillborn, dead at the time of delivery or dead during the first 24h of life. Factors that were positively associated with an increase in first 24h mortality risk included delivery during the colder months of the year (November-March), being of Wagyu breed, having a multipara dam, multiple (as opposed to single) birth deliveries, and delivery in larger herds. ​After adjusting for the fixed effects included in our multilevel model, 89% of the unexplained variation in first 24h mortality risk was at the calving event level. We propose that the data recording requirements of the NOSAI scheme are extended to include details of calving events (e.g. the presence or absence of dystocia) and details of the way in which calves are managed post delivery. This would allow more subtle risk factors for calf mortality to be identified which, in turn, will lead to refinement of recommendations for calf management during the first 24h of life in this area of Japan.

Stakeholder prioritization of zoonoses in Japan with analytic hierarchy process method.

There exists an urgent need to develop iterative risk assessment strategies of zoonotic diseases. The aim of this study is to develop a method of prioritizing 98 zoonoses derived from animal pathogens in Japan and to involve four major groups of stakeholders: researchers, physicians, public health officials, and citizens. We used a combination of risk profiling and analytic hierarchy process (AHP). Profiling risk was accomplished with semi-quantitative analysis of existing public health data. AHP data collection was performed by administering questionnaires to the four stakeholder groups. Results showed that researchers and public health officials focused on case fatality as the chief important factor, while physicians and citizens placed more weight on diagnosis and prevention, respectively. Most of the six top-ranked diseases were similar among all stakeholders. Transmissible spongiform encephalopathy, severe acute respiratory syndrome, and Ebola fever were ranked first, second, and third, respectively.

Review: Evaluation of Foot-and-Mouth Disease Control Using Fault Tree Analysis.

An outbreak of foot-and-mouth disease (FMD) causes huge economic losses and animal welfare problems. Although much can be learnt from past FMD outbreaks, several countries are not satisfied with their degree of contingency planning and aiming at more assurance that their control measures will be effective. The purpose of the present article was to develop a generic fault tree framework for the control of an FMD outbreak as a basis for systematic improvement and refinement of control activities and general preparedness. Fault trees are typically used in engineering to document pathways that can lead to an undesired event, that is, ineffective FMD control. The fault tree method allows risk managers to identify immature parts of the control system and to analyse the events or steps that will most probably delay rapid and effective disease control during a real outbreak. The present developed fault tree is generic and can be tailored to fit the specific needs of countries. For instance, the specific fault tree for the 2001 FMD outbreak in the UK was refined based on control weaknesses discussed in peer-reviewed articles. Furthermore, the specific fault tree based on the 2001 outbreak was applied to the subsequent FMD outbreak in 2007 to assess the refinement of control measures following the earlier, major outbreak. The FMD fault tree can assist risk managers to develop more refined and adequate control activities against FMD outbreaks and to find optimum strategies for rapid control. Further application using the current tree will be one of the basic measures for FMD control worldwide.

A quantitative risk assessment for bovine spongiform encephalopathy in Japan.

A predictive case-cohort model was applied to Japanese data to analyze the interaction between challenge and stability factors for bovine spongiform encephalopathy (BSE) for the period 1985-2020. BSE risk in cattle was estimated as the expected number of detectable cases per year. The model was comprised of a stochastic spreadsheet calculation model with the following inputs: (1) the origin and quantity of live cattle and meat and bone meal imported into Japan, (2) the age distribution of native cattle, and (3) the estimated annual basic reproduction ratio (R(0) ) for BSE. The estimated probability of having zero detectable cases in Japan in 2015 was 0.90 (95% CI 0.83-0.95). The corresponding value for 2020 was 0.99 (95% CI 0.98-0.99). The model predicted that detectable cases may occur in Japan beyond 2015 because of the assumption that continued transmission was permitted to occur (albeit at a very low level) after the 2001 ban on the importation and domestic use of all processed animal proteins for the production of animal feed and for fertilizer. These results reinforce the need for animal health authorities to monitor the efficacy of control measures so that the future course of the BSE epidemic in Japan can be predicted with greater certainty.

Computed tomography of the prostate gland in apparently healthy entire dogs.

OBJECTIVES: To describe the computed tomography (CT) features of the prostate gland and determine prostate size using CT in entire male dogs. METHODS: The prostate gland was evaluated in 35 dogs. Morphological features including homogeneity, delineation, shape and intraprostatic differentiation were assessed. Height, length, width, area, volume and attenuation values of the prostate gland were measured. Ratios of prostatic height (rH), length and width to the sixth lumbar vertebral body length were calculated. Relationships of prostatic dimensions with body weight and age were evaluated. RESULTS: The prostate gland was homogeneous in 29 dogs on non-contrast images and 18 of 24 dogs on postcontrast images. Transverse images revealed a semi-oval prostate gland in 29 dogs and irregularly shaped prostate gland in 6 dogs. A prominent median septum was observed in postcontrast images. Significant positive correlations were found between body weight and age and all prostatic dimensions except between age and rH. The mean ± sd values for attenuation were 59·3 ± 9·1 and 121·3 ± 22·7 HU in non-contrast and postcontrast image, respectively. CLINICAL SIGNIFICANCE: CT can be useful for evaluating morphological features of the prostate gland. Prostatic length or width is a better measure than height for computed tomographic estimation of prostate size.

Epidemiology of bovine spongiform encephalopathy in cattle in Hokkaido, Japan, between September 2001 and December 2006.

Between October 2001 and December 2006 an estimated total of 6 million cattle in Japan were tested for BSE, with 31 returning a positive result. Exploratory mapping, the space-time scan statistic, and ordinal logistic regression have been used to describe the epidemiology of the 24 cases identified in the prefecture of Hokkaido, and to quantify the risk factors for the disease. Two birth cohort groups were affected: cattle born during a period of seven months in 1996, and cattle born between 1999 and 2001. The descriptive spatial analyses showed that eight of the 10 cases born in 1996 were born in areas with a relatively high density of dairy farms in the east of Hokkaido, but that the 14 later cases were more widely distributed throughout the prefecture, with equal numbers of cases in the east and the west. These findings provide indirect evidence of a single localised contamination of the cattle feed supply in 1996, and recycling of the infection after 1999.

Variations in the prevalence of antibody to brucella infection in cattle by farm, area and district in Kenya.

Variations in the sero-prevalence of antibody to brucella infection by cow, farm and area factors were investigated for three contrasting districts in Kenya: Samburu, an arid and pastoral area: Kiambu, a tropical highland area; and Kilifi, a typical tropical coastal area. Cattle were selected by a two-stage cluster sampling procedure and visited once between August 1991 and 1992. Schall's algorithm, a statistical model suitable for multi-level analysis was used. Using this model, older age, free grazing and large herd size (> or = 31) were associated with higher seroprevalence. Also, significant farm-to-farm, area-to-area and district-to-district variations were estimated. The patterns of high risk districts and areas seen were consistent with known animal husbandry and movement risk factors, but the larger than expected farm-to-farm variation within high risk areas and districts could not be explained. Thus, a multi-level method provided additional information beyond conventional analyses of sero-prevalence data.

Assessing infections at multiple levels of aggregation.

The patterns of sero-prevalence of antibodies to four infectious diseases, representing a broad range of pathogens (bacteria: brucellosis; mycoplasma: contagious bovine pleuropneumonia; viruses: infectious bovine rhinotracheitis; protozoa: trypanosomosis) were investigated at three levels of organization (farm, area and district). Three contrasting districts in Kenya were compared: an arid and pastoral area (Samburu); a tropical highland area (Kiambu), and a tropical coastal area (Kilifi). Cattle in three districts were selected by two-stage cluster sampling between August 1991 and 1992. Schall's algorithm, a generalized linear mixed model suitable for multi-level analysis, was compared to ordinary logistic regression (OLR), which ignores clustering of responses; generalized estimating equations (GEE) or Jacknife, to account for clustering at the farm level; SAS VARCOMP, which provides normal-theory random-effects models. Schall's algorithm provided similar estimates to GEE (regression effects) and Jackknife (standard errors) for farm-level clustered data. Extending Schall's procedure for additional district and area-within-district random effects usually provided additional information. In general, models that included only a farm-level random effect consistently provided larger estimates of farms' variance components than did models with additional district and area random effects. The four type diseases exhibited various amounts of clustering. Brucellosis had moderate farm clustering plus some area and district clustering. Contagious bovine pleuropneumonia had only a small amount of clustering, mostly by area. Infectious bovine rhinotracheitis exhibited a large amount of clustering, primarily at the farm level. Trypanosomiasis antibody prevalence varied by district, area and farm. We believe that patterns of disease clustering identified by multi-level analysis can be used to better target high-risk units for disease control and guide research to understand disease transmission factors.

A comparison of different models for assessing variations in the sero-prevalence of infectious bovine rhinotracheitis by farm, area and district in Kenya.

The relative variability of the sero-prevalence of antibodies to infectious bovine rhinotracheitis (IBR) due to cow, farm, and agroecological area levels were investigated for three contrasting districts in Kenya: Samburu, an arid and pastoral area; Kiambu, a tropical highland area; and Kilifi, a typical tropical coastal area. Cattle were selected by two-stage cluster sampling and visited once between August 1991 and 1992. Data on animal, farm, and area factors were analyzed using Schall's algorithm and MLn (multi-level, n-level), two generalized mixed-model programs suitable for multi-level analysis. Most variation in IBR sero-prevalence was from farm-to-farm. This was reflected by the many farm-level fixed effects (farm size, disease control measures and type of breeding) significant in models both ignoring and accounting for single variance components (clustering) at farm, area, and district levels. Area-to-area and district-to-district variations were noted but the area and district variance components were one-third and one-fifth the size of the farm variance components for both methods. As farm-to-farm variation differed markedly by farm size and district, models in MLn were extended to allow for multiple farm-level variance components by these categories. For each, sero-prevalence of IBR increased with age and was significantly decreased on small-sized zero-grazing farms. These models, particularly the model with different farm variance components by districts, fit the data better and highlighted well that there was considerable farm-to-farm variation--differing by district--and that the available farm-level fixed effects did not predict IBR sero-prevalence well.