This study investigated the potential effects of amitraz on the pre- and postnatal development, behavior, and reproductive performance of offspring of parent rats given amitraz during pre-mating, gestation, and lactation. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and lactation up to weaning. Based on fluid consumption, the male rats received an average of 0, 5.7 ± 1.33, 13.2 ± 2.08, and 35.8 ± 3.42 mg/kg/day amitraz, and the female rats received an average of 0, 8.7 ± 4.42, 20.1 ± 9.60, and 47.6 ± 22.38 mg/kg/day amitraz, respectively. At 360 ppm, an increase in the incidence of abnormal clinical signs, a suppression in the body weight gain, a decrease in the food consumption and litter size, an increase in the post-implantation loss, and a decrease in the seminal vesicle weight were observed in the parent animals. In addition, a suppression in the body weight gain, a decrease in the grip strength, a delay in the negative geotaxis, an increase in the pre- and post-implantation loss, and a decrease in the number of live embryos were observed in the offspring. At 120 ppm, suppressed body weight gain and reduced food consumption were observed in the parent rats. Suppressed body weight gain and decreased grip strength were also observed in the offspring. There were no signs of either reproductive or developmental toxicity at 40 ppm. Under these experimental conditions, the no-observed-adverse-effect level of amitraz for parent rats and their offspring was estimated to be 40 ppm in rats.

A 2-month-old male Jeju native black calf with respiratory distress was died and requested to the Veterinary Pathology Laboratory of Jeju National University for diagnosis. Grossly, lungs were focally attached to the pleura and heart with fibrin. Purple red sublobar consolidations were distributed in both apical and cardiac lobes of lungs. Histopathologically, diffuse severe bronchointerstitial pneumonia characterized by multifocal necrotizing bronchiolitis, formation of numerous multinucleated syncytial cells in bronchiolar and alveolar lumens, and diffuse alveolar wall thickening were observed in lungs. Eosinophilic intracytoplasmic inclusions were observed in bronchiolar epithelial cells and syncytial cells. According to reverse transcriptase polymerase chain reaction (RT-PCR), bovine respiratory syncytial virus (BRSV) was detected in the lung of calf. Based on the histopathologic findings and RT-PCR, this calf was diagnosed as BRSV infection. In our best knowledge, this is the first case of BRSV infection in Jeju native black calf.

This study was carried out to find whether phenidone (1-phenyl-3-pyrazolidinone), a cyclooxygenase as well as a lipoxygenase inhibitor, exhibits the preventive effect on carbon tetrachloride (CCl₄)-induced acute liver injury in rats. Rats were pretreated with phenidone at a dose of 50 or 200 mg/kg (p.o.) once daily for 3 consecutive days before CCl₄ administration. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Malondialdehyde (MDA) production was determined as an index of lipid peroxidation in the liver and serum. The histopathological changes in the liver were also examined in each group. The reduction in body weights was significantly inhibited in the phenidone-treated group than in the CCl₄ control group. Significant increase in the relative liver weights of the phenidone-treated groups was observed compared with either the vehicle or CCl₄ groups. Elevation of serum AST and ALT activities occurred after CCl₄ treatment was significantly attenuated by the pretreatment with phenidone. The elevation of MDA levels in liver and serum were completely inhibited in phenidone-treated groups. The protective effects on phenidone-treated groups were confirmed histopathologically. These results suggest that phenidone may be a useful protector through modulation of hepatic inflammation in CCl₄-induced acute liver injury.

Among 203 avian pathogenic Escherichia coli (APEC) isolated from poultry with colibacillosis in korea, 14 isolates were selected from total 68 isolates transferred R plasmid and classified into 5 groups on the basis of antimicrobial minimal inhibitory concentration (MIC) pattern, farm source and O serotype. An association between clonal origin and R plasmid of them was investigated by R plasmid profile, restriction endonuclease analysis and pulsed-field gel electrophoresis (PFGE). The strains that showed the same or very similar antimicrobial MIC pattern, but different farm source and O serotype, revealed different PFGE pattern, which seemed to be different clonal origin. And the strains that showed the same MIC pattern and O serotype, revealed different PFGE pattern, seemed to be originated from different clone. Also the strains showing the same MIC pattern and farm source, but different O serotype, revealed to be different clonal origin. The strains that showed the same or similar MIC pattern, farm source, and O serotype, revealed identical or similar PFGE pattern, which seemed to belong to be one clone. Meanwhile, horizontal transfer of R plasmid seems to be common in APEC with regardless of O serotype and clone of the strains. These results indicate that rapid and accurate epidemiological survey of APEC can be possible by the combination of O serotyping, plasmid profiling and PFGE analysis following the classification of them into groups of antimicrobial drug resistance pattern.

A 3-day-old Appaloosa colt was examined because of acute onset of ataxia, left-sided head tilt, fever and heart murmur. The foal continued to nurse but became increasingly depressed and mild colic. On plain radiological examination, the foal was normal. Uroperitoneum was diagnosed following abdominocentesis. Postmortem examination revealed bladder rupture. The lesion was in the dorsomedial part of the bladder wall. We suggested that the cause of bladder rupture was parturient trauma. Even though the rupture was associated with trauma, the margin of rupture of bladder was clearly smooth and regular.

Linear and non-linear regressions were used to derive the calibration function for the measurement of roxithromycin plasma concentration. Their results were compared with weighted least squares regression by usual weight factors. In this paper the performance of a non-linear calibration equation with the capacity to account empirically for the curvature, y = ax∨b + c (b not equal to 1) is compared with the commonly used linear equation, y = ax + b, as well as the quadratic equation, y = ax²+ bx + c. In the calibration curve (range of 0.01 to 10 ㎍/mL) of roxithromycin, both heteroscedasticity and nonlinearity were present therefore linear least squares regression methods could result in large errors in the determination of roxithromycin concentration. By the non-linear and weighted least squares regression, the accuracy of the analytical method was improved at the lower end of the calibration curve. This study suggests that the non-linear calibration equation should be considered when a curve is required to be fitted to low dose calibration data which exhibit slight curvature.

This survey was carried out to investigate the seroprevalence of antibodies to Neospora (N.) caninum in dairy cattle raised in Kangwon province in Korea. A total of 349 sera collected from dairy cattle were tested for N. caninum antibodies using an indirect immunofluorescent antibody test (IFAT). Ninety six (27.5%) dairy cattle were positive by IFAT. Seroprevalence of cows was 28.9% (91/315) and seroprevalence of boars was 14.7% (5/34). The seroprevalences of cows were increased according to the ages from 19.6% in cows less than 2 year-old to 50.0% in cows more than 7 year-old. Among the seroprevalences of cattle according to the raised areas, five counties or cities, Wheongsung was 34.6% (27/78), Wonju was 29.3% (46/157), Hongcheon was 28.9% (13/45), Chuncheon was 15.0% (3/20) and Cheolwon was 13.3% (2/15). It was proved that dairy cattle raised in Kangwon provinces exposed extensively and seriously to N. caninum.

Caseous lymphadenitis (CLA) is a chronic and contagious disease of sheep and goats caused by Corynebacterium (C.) pseudotuberculosis. A four-year-old female Saanen dairy goat was submitted to the Animal Disease Diagnostic Center at National Veterinary Research and Quarantine Service. The clinical signs of the goat were emaciation, abortion and quadriplegia. The multifocal nodules of lymph nodes were encapsulated and filled with whitish caseous contents on the cut surface. Histopathologically, lymph nodes displayed suppurative and necrotizing granulomas. Caseous necrosis was diffusely observed in the center of the lymph nodes. Gram positive bacilli were shown in the lesions. C. pseudotuberculosis was isolated and confirmed by the biochemical tests and PCR assay. Based on clinical signs, histopathological examination and bacterial isolation, we diagnosed this case as CLA. To our knowledge, this is the first report of CLA in a Saanen dairy goat in Korea.

A trematode species belonging to the genus Prosthogonimus (family: Prosthogonimidae) was collected in August, 2004 from the bursa of Fabricius of a single Little Grebe, Tachybaptus ruficollis, caught in Chuncheon, Korea. Five specimens were collected in total and fluke morphology was examined under using a light microscope. The average parasite size was 5.6 × 3.2 mm (length × width; based on 4 specimens). The genital pore was located on the anterior right margin of the oral sucker. The cirrus sac was strongly sinuous and extended beyond the intestinal bifurcation to the ventral sucker. The prepharynx was extremely short and the pharynx was small. The vitellaria consisted of 6 follicle bunches and extended from the ventral sucker to the posterior of the testes. Finally, the uterus filled the body cavity posterior to the testes. In addition, there were no heavy slings occurred anterior to the testes. Based on these morphological characteristics, the parasites were identified as P. cuneatus. The discovery of P. cuneatus within a Little Grebe constitutes a new host identification and a new geographical record. This is the first reported case of Prosthogonimus infection within wild birds in Korea.

The large amount of tissue culture medium (TCM), which contains some of the active secretory components of Korean wild ginseng (KWG; Panax ginseng) such as saponins, is usually discarded after harvest of KWG. The present study was aimed to investigate the efficacy of oral administration of the TCM-KWG on growth performance and diseases resistance in broiler chickens. A day old broiler chickens randomized in 6 groups (n=60/groups) were administered orally with 0, 2, 4, 8, 16 and 32 mL/L TCM-KWG through drinking water for 5 weeks and examined the change of weight gain, feed intake and blood components. Also, five weeks old broiler chickens (n=15/groups) were challenged orally with Salmonella (S.) gallinarum and investigated the mortality in broiler chickens. An average weight gain and feed intake significantly didn't change in TCM-KWG administration groups as compared to control group. The concentration of calcium (Ca), phosphate (Pi) and potassium (K) in serum were increase by TCM-KWG administration in broiler chickens. We also found that oral administration of TCM-KWG through drinking water significantly reduced the mortality in broiler chickens experimentally infected with virulent S. gallinarum. The results of this study indicated that TCM-KWG administration may elevate the resistance on disease and improved the skeleton formation and body homeostasis of chickens, and TCM-KWG can be used as a cost-effective and environmentally alternative additives to control of the disease and growth.