The objective of this study was to determine appropriate sample size that simulated different assumptions for diagnostic test characteristics and true prevalences when designing serological surveillance plan for pullorum disease and fowl typhoid in domestic poultry production. The number of flocks and total number of chickens to be sampled was obtained to provide 95% confidence of detecting at least one infected flock, taking imperfect diagnostic tests into account. Due to lack of reliable data, within infected flock prevalence (WFP) was assumed to follow minimum 1%, most likely 5% and maximum 9% and true flock prevalence of 0.1%, 0.5% and 1% in order. Sensitivity were modeled using the Pert distribution: minimum 75%, most likely 80% and maximum 90% for plate agglutination test and 80%, 85%, and 90% for ELISA test. Similarly, the specificity was modeled 85%, 90%, 95% for plate agglutination test and 90%, 95%, 99% for ELISA test. In accordance with the current regulation, flock-level test characteristics calculated assuming that 30 samples are taken from per flock. The model showed that the current 112,000 annual number of testing plan which is based on random selection of flocks is far beyond the sample size estimated in this study. The sample size was further reduced with increased sensitivity and specificity of the test and decreased WFP. The effect of increasing samples per flock on total sample size to be sampled and optimal combination of sensitivity and specificity of the test for the purpose of the surveillance is discussed regarding cost.

Objective-To inoculate white-tailed deer (Odocoileus virginianus) during the sixth or seventh week of gestation with bovine viral diarrhea virus (BVDV) and observe for signs of reproductive tract disease during a 182-day period. Animals-10 pregnant white-tailed deer (8 seronegative and 2 seropositive [control deer] for BVDV). Procedures-Deer were inoculated with 1 of 2 deer-derived BVDV strains (RO3-20663 or RO3-24272). Serum anti-BVDV antibody titers were determined prior to and 21 or 35 days after inoculation. Virus isolation (VI) procedures were performed on tissues from fetuses and does that died and on blood samples collected from live fawns. Ear notch specimens obtained from live fawns were assessed by use of BVDV antigen-capture ELISA (ACE). Results-Both RO3-20663-inoculated seropositive deer gave birth to apparently normal fawns. Among the RO3-24272-inoculated seronegative deer, 1 died, and 1 aborted and 1 resorbed their fetuses; among the RO3-20663-inoculated seronegative deer, 3 died, 1 aborted its fetus, and 1 gave birth to 2 fawns that were likely persistently infected. On the basis of VI and ACE results, those 2 fawns were positive for BVDV; both had no detectable neutralizing anti-BVDV antibodies in serum. Conclusions and Clinical Relevance-Reproductive tract disease that developed in pregnant white-tailed deer following BVDV inoculation was similar to that which develops in BVDV-exposed cattle. Methods developed for BVDV detection in cattle (VI, immunohistochemical evaluations, and ACE) can be applied in assessments of white-tailed deer. Fawns from does that had serum anti-BVDV antibodies prior to inoculation were protected against BVDV infection in utero.

The present study was carried out to develop a sustained release implantable formula of bovine somatotropin (SRIF-BST) and to examine its sustained ralease effect. The SRIF-BST was produced by coating a solid pellet, which was comprised of BST and an excipient, made of a biodegradable polymer and poloxamer, which are capable of regulating the rate of BST release. The coated membrane of SRIF-BST was observed with a field emission scanning election microscope. The thickness of the coated membrane was approximately 1 ㎛, and the pore sizes of the coated membrane surface were below 10 ㎛. In dissolution test, the release duration of the SRIF-BST maintained for 10 days, whereas the release duration of the control BST formula maintained for 3 days. In weight gain assay and tibia test of hypophysectomized rats, the release duration of the SRIF-BST treated group was 12 days and the net weight gain was 53.16 g, also the tibia length and strength of the SRIF-BST treated group was increased 10.5% and 23.1% compared with those of the control group, respectively.

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are ubiquitous and can contaminate the food chain. A study monitoring PCD/Fs in imported meat was conducted at the National Veterinary Research and Quarantine Service (NVRQS, Republic of Korea) in order to maintain food safety from the bioaccumulative PCDD/Fs. Seventeen PCDD/Fs with toxic equivalency factors (TEFs) established by World Health Organization (WHO, 1998) were analyzed in imported beef, pork, and chicken by high resolution gas chromatography/mass spectrometry (HR-GC/MS). Results of the monitoring for the last 5 years are presented. The levels of PCDD/Fs were similar to other studies except two unusually high concentrations in pork and beef. Excessive levels greater than the Korean provisional maximum residue limit of PCDD/Fs were found in a sample of pork imported from Chile and a sample of beef imported from U.S, and those products were rejected and returned. These was no obvious trend or differences with respect to time or origin of meat in this study.

We have investigated efficiency of a recombinant subunit Pasteurella multocida toxin (PMT) that was mixed with a vaccine consisted of inactivated whole cells of Bordetella bronchiseptica, P. multocida (type A and D). For verification of the efficacy of the vaccine, all experimental pigs (suckling piglets, sow and gilts) in the three farms were vaccinated. Antibody titers against B. bronchiseptica and P. multocida type A of the vaccinated pigs by microplate agglutination were significantly higher than those of the control pigs (p less than 0.05). Similar patterns were observed in the analysis of anti- PMT neutralizing antibody by serum neutralizing method using Vero cell (p less than 0.05). Anti- P. multocida type D antibody titer of the vaccinated sows and gilts by ELISA showed significant differences with those of the non-vaccinated pigs (p less than 0.05). Although antibody titers increased, it was unable to fine out the differences in the clinical signs between the vaccinated and non-vaccinated pigs. However, the increase in body weight of the vaccinated piglets was observed in comparison with the non-vaccinated piglets on a farm. At slaughtering of the pigs, pathological lesions in the turbinate bones of the vaccinated pigs were significantly lower than those of the non-vaccinated pigs (p less than 0.001). These results suggested that efficacy of the vaccine in pigs demonstrated to protect against atrophic rhinitis in Korea.

Porcine reproductive and respiratory syndrome (PRRS) is the most economically important viral infectious disease in pig populations worldwide. This study was conducted to better understand the epidemic and dynamics of PRRS virus (PRRSV) on each farm and to evaluate the risk of PRRSV infection in Korea. Interviews with pig farmers were carried out to obtain PRRS vaccination programmes in 60 pig farms throughout Korea. Blood samples were also collected from the 59 pig farms to investigate outbreak patterns of each farm. Vaccination against PRRS was performed in 16.7% farms for breeding pigs and 8.3% of farm for nursery pigs. According to the seroepidemiological analysis, 56 (94.9%) out of 59 farms were considered to be affected by PRRSV infection. The results revealed that 68.9% of sows tested were seroconverted and interestingly, gilt herds had the highest seropositive rate (73%), suggesting that gilts may play a key role in PRRSV transmission in sow herds. Among the PRRS-affected piglet herds, 33 (55.9%), 14 (23.7%) and 6 (10.2%) farms were initially infected with PRRSV during the weaning, suckling and nursery period, respectively. It seems likely, therefore, that PRRSV infection predominantly occurs around the weaning period in piglet herds. Based on antibody seroprevalence levels in both sow and piglet groups, we were able to classify patterns of PRRSV infection per farm unit into 4 categories; category 1 (stable sow groups and non-infected piglet groups), category 2 (unstable sow groups and non-infected piglet groups), category 3 (stable sow groups and infected piglet groups), and category 4 (unstable sow groups and infected piglet groups). Our data suggested that 43 (72.9%) farms were analysed to belong to category 4, which is considered to be at high-risk for PRRS outbreak. Taken together, our information from this study will provide insight into the establishment of an effective control strategy for PRRS on the field.

A 6-year-old female Boston terrier dog was presented with seizure episode, forelimb paraparesis, excessive panting, and ataxia. On physical and neurological examination, episcleral vessel engorgement, delayed postural reaction, delayed pupillary light reflex (both direct and consensual), and crossed forelimb were noted. Serum biochemical profiles were not remarkable other than mildly elevated hepatic enzymes. On cerebrospinal fluid analysis, elevated protein concentration was observed. In magnetic resonance imaging scans, the left frontal brain lesion with ring enhancement strongly suggested the presence of intracranial tumor. Concurrently, secondary hydrocephalus and syringomyelia were also observed. The dog was euthanized at 4 months after initial presentation because of aggravated neurological signs. This case was definitely diagnosed as an intracranial anaplastic oligodendroglioma based on postmortem histopathologic examination.

A 2-month-old female Abyssinian cat was presented with a severe ascites, cyanosis, and exercise intolerance. Diagnostic studies revealed Ⅴ/Ⅵ holosystolic murmur, sinus tachycardia, generalized cardiomegaly with marked left atrial enlargement and shunt flow between left and right ventricles. Doppler study showed bi-directional shunts in rest and right-to-left shunt after exercise. Based on clinical signs and diagnostic findings, the cat was diagnosed as a reversed ventricular septal defect. The cat was treated with furosemide, nitroglycerine, dobutamine and oxygen supplement. Despite initial improvement of clinical signs after initiation of medical treatment, the cat died of sudden cardiac arrest. Necropsy revealed a perimembranous ventricular septal defect.

Gastrointestinal stromal tumor (GIST) is one of the mesenchymall tumors originated from gastrointestinal submucosa. A 10 year-old, male, mixed breed dog with persistent diarrhea, anorxia and lethargy was referred to Haemaru Animal Referral Hospital. Large mass originated from the transverse colon was observed and large amount of ascites and free gas were found on abdominal radiography and ultrasonography. The ascites was septic exudate mixed with bacteria that consisted with intestinal perforation. These was no metastatic lesion. This mass was tentatively diagnosed as adenocarcinoma, leiomyosarcoma (LMS) and lymphosarcoma and surgical resection and histilogical examination were planned. However, according to owner's request, the patient was euthanized and then the necropsy was performed. About 10 cm sized mass originated from the cecum, ascending colon and transverse colon was adhered to surrounding mesentery and the perforation and large amount of asicites were observed. GIST was suspected on histopathologic examination and confirmed according to CD117 expression in immunohistochemistry. GIST, derived from interstitial cells of Cajal, can be distinguished from LMS and leiomyoma (LM) on the basis of expression of CD117 (KIT) immunohistochemically. GIST has a different biological behavior and clinical course compared with LMS and LM, therefore definite diagnosis for GIST using immunohischemistry is clinically important to predict the precise prognosis of the patient.

Comparative studies of histopathologic lesions from 23 purified protein derivative (PPD) positive cattle, 21 slaughter cattle found with tuberculosis, and 11 tuberculosis-positive elk (Cervus elaphus) were performed. PPD positive cattle did not show specific histopathologic lesions in all 23 heads that were no visible lesion reactor. Slaughter cattle found with tuberculosis revealed microscopically classical granulomatous lesion (tubercle) with central caseous necrosis surrounded by mantle of epithelioid cells and Langhan's giant cells capsuled by connective tissue in lung. Elk was noted with some different lesion patterns with classical granulomatous lesion and suppurative abscesses that was composed of fibrin, degenerated cells without having connective tissue. In addition, many Langhan's giant cells infiltration in alveoli at peripheral lesion were observed in some cases of classical granulomatous lesion and suppurative abscesses.