Historical backgrounds of veterinary epidemiology in Europe and America are compared with those in Japan. The activities played by epidemiologists in these countries are also briefly compared. The role to be played by epidemiologists in decision making continues to increase as the range of subjects to be covered by veterinarians are expanding in such areas as food safety, the control of zoonoses, environmental health, antibiotic resistance and animal welfare. Accordingly, the OIE has expanded its activities in these fields, and plans to hold an international conference in 2009 with aims to strengthen the veterinary education on specific subjects including epidemiology.

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Veterinary epidemiology has received increased attention over the past last 10 years as a result of the rising threat of emerging zoonoses, such as Avian flu and BSE, and food-borne disease occurred in Japan. Therefore, some Veterinary schools in Japan had started the subject for Veterinary Epidemiology in their curriculum. Of 15 Japanese Veterinary schools, 5 schools educated the subject for Veterinary Epidemiology in 2008. However, Veterinary Epidemiology had been educated in the subjects for Veterinary Public Health, Animal Hygiene and Veterinary Infectious Disease in remaining 10 Veterinary schools. The Japan society of Veterinary Epidemiology propose that Veterinary Epidemiology should be educated as an independent subject in Veterinary Education and should be required to earn 2 credits (90 minute weekly classes held during one half-year semester).

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Current situations of veterinary epidemiology education in foreign countries were overviewed based on the information acquired through available materials and personal interviews. Veterinary epidemiology related courses at universities in North America and Europe are mainly established for graduate students, and provide practical skills for data analysis, surveillance, disease control, etc. Many courses aim at training experts on veterinary public health, and veterinary epidemiology is taught as a main subject in veterinary public health programs. Given that many courses has been newly established recently, increased public awareness of food safety and zoonotic diseases these days are considered to boost demands for veterinary epidemiologists worldwide. In order to meet these demands, education on veterinary epidemiology in Japan needs to be strengthened referring to overseas programs.

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Veterinary epidemiology is a useful study in the field of animal health science. In this report, disease identification and reporting system, as well as disease prevention and control system currently used by central and local governments were discussed. Epidemiological research works, some of which were done by the National Institute of Animal Health and others by veterinary universities were summarized. Post-graduate veterinary epidemiological education system, which were conducted at the National Institute of Animal Health, were also introduced in this paper.

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Epidemiology is basically the science for human population. Veterinary epidemiology has much wider targets to cover, for example various kinds of animals, environment, quality of life, etc. Veterinary epidemiology has not been set as an independent unit of veterinary school, but now it becomes an important part of veterinary science.
Veterinary epidemiology covers food safety, zoonosis, symbiosis of human and animals, environmental health.
Society of Veterinary Epidemiology has a responsibility to contribute to Japanese society through the activity to promote epidemiology into veterinarian

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We examined the dynamics of antibiotic resistance and pulsed-field gel electrophoresis (PFGE) patterns of E. coli isolates from health swine feces. Ten piglets were randomly chosen in each of 4 pig-raising farms. Feces were collected at the piglet stage, growing stage and at the finishing stage. Ten strains were isolated from each sample and isolates identified as E. coli were used for analysis. All the 553 strains, isolated at the piglet and growing stage of 3 farms, showed resistance against 2 to 9 antibiotics. Strains isolated at the finishing stage showed reduction of antibiotic resistance, and 70 of 294 strains showed susceptibility for all the 15 antibiotics tested. Similar reduction was observed in the remaining farm. However, in this farm, antibiotic susceptible strains were isolated from all stages, being 62 of 300 strains susceptible for all the antibiotics. The majority of strains showing the same antibiotic resistance pattern showed the same PFGE pattern, but also different PFGE patterns were found among those strains, even they have been isolated from the same animal.
These results demonstrated that, the E. coli strains of each farm might be originated from multiple sources, and, although a same strain could remain along the stages, changes of antibiotic resistance patterns and PFGE profiles occurred in a short time period. Thus, for monitoring systems related to food safety, analysis at the finishing stage seems the most recommended. Moreover, studies to elucidate the causes of changes in the E. coli strains of intestinal flora might be of great interest.

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The Tsushima leopard cat (Prionailurus bengalensis euptilura) is indigenous to the island of Tsushima in Nagasaki prefecture, Japan, and was declared as a critically endangered species by Species Conservation Act of Japan. In 1996, one of the wild Tsushima leopard cats was found to positive for FIV (feline immunodeficiency virus) that was original in domestic cats. Many captive or feral domestic cats can be found all over the island, and they might carry the FIV to the Tsushima leopard cat. According to the result of this survey, FIV infection rates in captive domestic cats were 13.6% (38/280) in Kami-shima (Northern Island) distributed the population of Tsushima leopard cats, and 10.6%(46/433) in Shimo-shima (Southern island) not confirmed the population. It was found through the GIS analysis that there are some specific areas where the FIV infection risks for the Tsushima leopard cat are much higher than other areas. It was recommended that it should be intensively done the action for prevention the Tsushima leopard cat from the FIV infection in this high risk area.

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In April 2008, questionnaires to investigate wildlife animals and their damage were sent to 687 public pastures throughout Japan. The proportion of the public pastures, answered to observe each mammalian species, were in the following orders ; red foxes, Japanese hares and mountain hares, raccoon dogs, sika deer, etc. Sika deers were the most frequently identified in northern island and the major problems caused by them were “damage to grown forage grasses for cattle” and “destroying fences in the pasture”. Damage problems by other wild animals observed were “wrapped silage punctured or torn” and “concentrate feed stolen” by crows “facilities intruded and broken” and “fears of disease transmissions” by red foxes, raccoon dogs and bears. This study was the first nation-wide survey on damage problems by wild animals at public pastures in Japan.

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We surveyed the health management practices in horse holdings except racehorse facility using postal questionnaires. The survey response rate was 50% (938/1,875). From the purpose of keeping horses, holdings were classified into seven types : equestrian clubs, private owners, educational facilities, exhibition facilities, Bannei horse racing facilities, fattening facilities, and other. As for the number of horses kept per holding, equestrian clubs have the largest number (median : 15), while other holdings have only six or less horses. Concerning health managements, the inspection of equine infectious anemia has been carried out at more than 80% of equestrian clubs and educational facilities in the least five years, while done at 50% of private owner's holdings and 60% of fattening facilities. Vaccination of equine influenza and Japanese encephalitis was conducted at 90% of equestrian clubs and 60% of educational facilities.
However, only 40% of private owner's holdings and 60% of fattening facilities were vaccinated horses against these diseases. The health management practices varied among types of horse holdings. It is important to consider different characteristics of each holding type to implement control measures against infectious diseases.

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To select efficient and effective option of animal disease control, economic appraisal helps both farm manager and regional or national authority. Economic appraisal can be thought as a comparison among two or more options or states, one of which is regarded as benchmark. Even good deals of economic appraisals of animal disease have done, its theoretical background is still unclear.
In this research, we tried to show the importance of the scope and the timing in calculating the cost of animal disease from economics and accounting point of view. We classified literatures published in Japan by their scope in terms of actor and costs. Then we reviewed whether they can be justified from theoretical and practical standpoint.
Main results are followings : firstly, what should be included in the cost depends on the scope and the timing of the appraisal. From theoretical point of view, to evaluate the economic loss of animal disease, we should focus on accounting cost that includes wasted capital invested on diseased animals. On the other hand, to evaluate the economic efficiency of disease control options, opportunity cost should be included as its cost. Existing literatures don't always fit to this framework, however, most of them can be justified for practical reason. Secondly, impact on market structure caused by animal disease or disease control should be taken into considerations. Increase in supply may not be accomplished without price drop, which has often been ignored in previous researches.

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Bats belong to the order Chiroptera and are divided into two suborders, Microchiroptera (microbats) and Megachiroptera (megabats). In Australia, there are 13 species of megachiropterans in the genus Pteropus, 8 of which are flying foxes. Four species of the flying foxes, grey-headed (P. poliocephalus), black (P. alecto), little red (P. scapulatus) and spectacled (P. conspicillatus), seem to play an important role as reservoir hosts for important zoonotic viruses in spreading and establishing infection in some species of animals including humans.
A few of the several novel viruses isolated from flying foxes in Australia in the 1990s, such as Hendra virus, Menangle virus and Australian bat lyssavirus, are important as zoonotic pathogens. Hendra and Menangle viruses are characterised as Paramyxoviridae. Hendra virus causes respiratory and neurological signs and often fatal illness in both horses and humans. Menangle virus which caused fetal deaths in a piggery may cause a febrile, influenza-like illness in humans. The Australian bat lyssavirus is considered to be a new species within the genus Lyssavirus and is most closely related to serotype 1 (classical rabies) and serotype 5 (European bat lyssavirus 1). This virus causes neurological signs in bats and can cause a fatal human illness.

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The objective of the present study was to determine the factors associated with the occurrence of decreased pigs born alive (PBA) in parity 2 (D-PBA). The sow data used were farrowing records of 51,259 sows farrowed in parity 1 and parity 2 from 2001 to 2005 relating to 104 herds in Japan. D-PBA was defined as the same or fewer numbers of PBA in parity 2 compared to PBA in parity 1. Mixed-effects logistic regression analysis with contrasts was applied to the results of the study. Of the 51,259 sows studied, 49.5% manifested an occurrence of D-PBA. A high occurrence of D-PBA in sows was associated with PBA 13 or more pigs in parity 1, lactation length 17-19 days, weaning-to-conception interval (WCI) 7-12 days and being conceived during summer in parity 1 (P<0.05). Three two-way interactions between PBA in parity 1 x season of conception, WCI x season of conception, and WCI x PBA in parity 1 were found for the occurrences of D-PBA (P<0.05). In sows having PBA≥13 pigs in parity 1, no difference between the four season groups was found for the occurrences of D-PBA (P<0.05). Meanwhile, in PBA<13 pigs in parity 1, sows conceived during summer had higher occurrences of D-PBA than those conceived during the winter and the fall (P<0.05). Among all the groups categorized by season of conception and PBA in parity 1, sows with WCI 7-12 days had the highest occurrence of D-PBA among the WCI groups (P<0.05). No differences were found in the occurrence of D-PBA among the five age groups of sows at first conception. Additionally, a slight difference (0.3-0.5%) in the occurrence of D-PBA was found between the groups categorized by lactation length from 17-19 to ≥26 days (P<0.05). In conclusion, the occurrence of D-PBA was suggested to be related to the large PBA, the WCI 7-12 days and the conception during summer.

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In Paraguay, vaccination programmes for infectious bursal disease (IBD) virus control planned by foreign vaccine manufacturers are commonly used, which are not always adapted to the particular conditions on the farm and to the status of maternally derived antibody (MDA) in chicks. The objectives of this study were to fit a generalised linear mixed model for MDA titre values for estimating optimal days of age for IBD vaccination in broiler flocks, and to assess how optimal vaccination timing estimates differ between flocks. The MDA titre values were measured by enzyme-linked immunosorbent assay (ELISA) with sera collected from 20 chicks per flock (n=14) at 1, 8, 15 and 30 days of age. Markov chain-Monte Carlo method was used to fit a generalised linear mixed model for the dependent variable “log-transformed MDA” at 1, 8 and 15 days of age. Optimal days of age for IBD vaccination for the reference flock, and differences in optimal days of age between flocks were estimated. The study chicks were vaccinated according to the estimated optimal days of age. Data collected at 30 days of age were only used for checking a rise in antibody titres after vaccination. The mean log-transformed MDA titre values at hatch was estimated 12.35 [95% Bayesian credible interval (BCI) : 12.16-12.53] and half-life period of log-transformed MDA titre values was 3.7 days (95%BCI : 3.5-3.9). Given the use of intermediate vaccine with breakthrough titre value of 125, the optimal vaccination timing for the study flocks is at least seven days later than the recommended timing by the vaccine manufacturers. The results can be used as a standard to create IBD vaccination programmes, however it is recommended for estimating the vaccination timing to measure the MDA status on a routine basis.

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We conducted a workshop for veterinarians who are involved in the BSE active surveillance as a part of evaluation to identify problems and get ideas for solutions concerning BSE surveillance system in Japan. In this paper, we report how to plan such a workshop and its outcomes. Every participant was satisfied with the workshop mainly due to interactive opinion-exchanges (intellectual dialogue) among themselves. An ultimate goal of veterinary epidemiological research is to identify problems and propose solutions in fields of public and animal health. Therefore, workshop would be a useful tool to enhance activities among all stakeholders and achieve such a goal of epidemiological research.

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[in Japanese]

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[in Japanese]

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