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.

A castrated male, 4-year old, Dachshund weighing 5.3 kg with an acute history of anorexia, vomiting, severe depression, and hypothermia for 1 day was referred. Severe leukopenia, mild increased hepatic enzymes, and mild imbalanced electrolyte were found on laboratory tests. There are no remarkable findings on abdominal radiographs. Ultrasonography showed multifocal heterogeneous and hypoechoic round regions in the liver. Ultrasound guided fine needle aspiration and drainage were performed and hepatic abscess was diagnosed. The patient was recovered normally without any complications through aggressive medical treatments from the result of culture and sensitivity test.

Mesenteric torsion was diagnosed in a 2-year-old, spayed female Miniature Schnauzer. The patient was presented with acute depression, vomiting, lethargy and hematochezia. On physical examination, severe dehydration, tachycardia, tachypnea, weak femoral pulse, delayed capillary refill time and pale mucous membrane were found and the dog was in shock. Radiography and ultrasonography revealed intestines distended with gas, ascites and the "C" shaped distended intestine. Medical treatments including fluid therapy, analgesics, antibiotics and lidocaine for reducing reperfusion injury were applied. And then, the mesenteric torsion was definitively diagnosed through exploratory laparotomy and intestinal resection and anastomosis were performed. The dog made an uneventful recovery and was free of clinical sign one week after surgery. Mesenteric torsion is an unusual and life-threatening disease in dogs. It has usually been described in the middle and large breed dogs, especially German Shepherds. However, the mesenteric torsion should be included in the differential diagnostic lists for acute abdomen even in small breed dog. The mortality rate of mesenteric torsion can be reduced through prompt diagnosis, proper preventive therapy for shock and reperfusion injury and emergency surgery.

Pesticides are extensively used for the control of crop pests in agriculture and forestry. Organophosphate (OP) and carbamate pesticides are especially effective for the control of a variety of harmful insects. However, these cholinesterase inhibitors are also dangerous to non-target organisms (wildlife and other animals) because of their high acute toxicity. Most poisonings by pesticides occur as a result of misuse or accidental exposure, but intentional killing of unwanted animals also occurs. At the request of a local autonomous entity, we investigated wild bird poisonings by pesticides from 2003 to 2007. The 207 suspicious samples of pesticide poisoning based on the necropsy were analyzed by GC/NPD, GC/FPD, or GC/MSD. We looked for trends in the identification of pesticides in wild birds thought to have died from poisoning. Pesticides were determined in 59% of the total samples analyzed. Phosphamidon and monochrotophos were the most common pesticides identified, which amounted to 77% of the subtotal. Other OP and carbamate pesticides were also found in various concentrations from dead wild birds. The determined rates of pesticides were as high as 86% and 76% in 2003 and 2006, respectively, during an outbreak of avian influenza in Korea.

We report here two cases of Rhodococcus (R.) equi-causing pneumonia of Throughbred foals in Gyeonggi-do in 2006. R. equi was isolated from the lung lesions of the dead foals, and from the feces and soils on the farms where the clinical cases of R. equi infection occurred. The isolates were characterized by biochemical properties, polymerase chain reaction for vapA gene and antimicrobial susceptibility. In drug susceptibility test, erythromycin, gentamycin, vancomycin, and rifampin were found to be the most susceptible for all isolates. These results suggest that R. equi pneumonia may be endemic in the horse-breeding farms in inland Korea and the farm environment may be widely contaminated with virulent R. equi.

Many neurotoxigenic clostridia are found in soil. Among animals, birds are especially susceptible to botulism, perhaps because they feed on insects, invertebrate carcasses, and decayed feeds contaminated with spores of Clostridium (C.) botulinum. C. botulinum type C is mainly involved in avian botulism. In the summer of 2005, death of a mute swan (cygnus olor) living in the pond of large bird cage was found in Seoul Grand Park Zoo. The birds presented presumptive clinical signs of botulism, such as ruffled hackle feathers, abnormal posture of the head, weakness, and flaccid paralysis. At that time, pond water in the breeding facilities was drained for 7 days, but there were still remained water containing sediment of feed and feces. Therefore, botulism was suspected and an experimentation were made to detect C. botulinum in the dead mute swan. Gross post-mortem findings of a mute swan showed jelly-like hemorrhagic contents in the intestine, sands and vegetations in the stomach. C. botulinum was isolated from the liver, small intestine and large intestine samples. Botulism was also confirmed by mouse inoculation test with the organ samples. With PCR, a gene encoding C. botulinum type C toxin was detected for the several organs of the mute swan died. These results suggested that death of mute swan was caused by C. botulinum type C.

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.

A four-month-old intact femlae Abyssinian cat was present for routine health evaluation, because her littermate was recently died of ventricular septal defect. Diagnostic imaging studies showed a large caudal paracardiac mass in thoracic radiography and homogenous mass adjacent to heart in the echocardiography. Further echographic study revealed that the mass was liver and the diaphragmatic line was intact. The positive contrast celiogram revealed that no extravasation of the contrast media across the diaphragm and the prolapse of diaphragm into the pleural cavity. Based on our diagnostic imaging studies, the case was diagnosed as diaphragmatic deformity in a cat mimicking a cardiac mass.

A six-year-old, female Jin-do dog was referred for the recurrence of vaginal prolapse. Less than 7 months previously, the dog with the vaginal prolapse had been treated with hormone therapy because ultrasonography had identified a single follicular cyst in the left ovary. Three months after the first visit, the dog came into heat and the vaginal prolapse recurred. Ultrasonography showed multiple follicular cysts in both ovaries and radioimmunoassay detected a plasma estradiol-17β concentration of 13.3 pg/ml. Treatment involved the repositioning of the vaginal prolapsed, ovariohysterectomy and the resection of the protruding tissue. The dog had been completely recovered two months later after the treatment.

A calmodulin-dihydrofolate reductase (DHFR) sandwich fusion protein was generated by insertion of calmodulin into the β-bulge region of DHFR to observe the effects of structurally constraining the calmodulin structure. The calcium binding properties of the sandwich protein were almost identical to calmodulin. Similar to calmodulin (10.7 μM), the sandwich protein bound four equivalents of calcium, with half saturation (K∧0.5) observed at a [Ca²+] of 8 μM. However, nicotinamide adenine dinucleotide (NAD) kinase activation property of the sandwich protein was lower than that of calmodulin. The sandwich protein activated NAD kinase, but to only half of the level obtained with calmodulin. The K∧0.5 for both calmodulin and the sandwich protein were approximately the same (1-2 nM). Methylation analyses of the sandwich protein show that insertion of calmodulin into DHFR results in a large decrease in methylation. The V∧max observed with the sandwich protein (95 nmole/min/ml) was only 22% of the value observed with calmodulin (436 nmol/min/ml) in the presence of calcium. Addition of trimethoprim to the reaction significantly inhibited the observed methylation rate. Overall, the data suggest that the insertion of calmodulin into the DHFR structure has little effect on calcium binding by the individual lobes of calmodulin, but may constrain the lobes in a manner that results in altered interaction with the calmodulin-dependent proteins and severly perturbed the methyltransferase recognition site.