The present study was performed in order to define the optimum effective dose of dopamine for dogs. Thirty-nine anesthetized healthy mixed-breed dogs were given three different doses of dopamine by infusion (3, 10, or 20μg/kg, min), and regional blood flow was measured using colored microspheres in the brain, heart, kidneys, stomach, intestines, liver, and lungs. Blood flow in the brain was maintained unchanged. Blood flow in the heart increased in proportion to the increase in cardiac output, suggesting the need to avoid overloading the cardiac muscle. Blood in the digestive tract moved to the various organs as they required it. Generally speaking, a small dose of dopamine activates dopamine-specific receptors so that renal and coronary arteries expand, a larger dose activates β₁-adorenoceptors in the heart so that cardiac output increases, and a still larger dose of dopamine activates α-adorenoceptors in the whole body so that peripheral arteries contract. In our study, the larger the dose, the greater was the activating effect on α-adorenoceptors in all organs. We also found that the effect of dopamine was influenced not only by how it activated these receptors, but also by the autoregulation system of blood flow. Moreover, the group of dogs receiving 10μg/kg/min of dopamine showed a satisfactory increase of renal blood flow, cardiac blood flow and cardiac output. That is, a large dose of dopamine, such as the 10μg/kg/min used in this study, which is larger than usual, was more effective and safer than it was thought. These findings indicated the possibility of raising the upper limit of the dosage in administering dopamine to dogs clinically.

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The accuracy of hematological values calculated by an automated blood cell counter (Sysmex KX-21NV) was evaluated in dogs and cats. This apparatus has the advantage of simultaneous automatic counting of eight hematological parameters in one minute, namely white blood cell (WBC), red blood cell (RBC), hemoglobin (Hb), hematocrit (Ht), mean corpuscular diameter (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and blood platelets (Plat). Reproducibility tests were performed continuously ten times for each sample using 10μl of whole blood from two dogs and two cats. There was good reproducibility in every item in both dogs and cats. Correlation tests were also done, and compared with another kind of apparatus of the same purpose, Celltac MEK-6158 made by Nihon Kohden, using 46 dogs and 36 cats. There was a correlation between the results from the two in all items except MCHC. This newly developed automatic blood cell counter is easy to handle, with no need to input tested species. Therefore, it is considered that this apparatus is handy and useful for clinical use not only in dogs and cats but also in other small animals.

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A thirteen-year-old male cat with callous skin around the head and neck came for treatment. Stamp specimens obtained from the afflicted area revealed a large number of small-to-large yeast-like fungi with thick capsules on the surface of the skin. Mycological and histopathological examinations identified the disease as Cryptococcus neoformans. The infection was observed only on the surface of the skin, and histopathologically, many of these pathogens were found among the hair follicles, so the cat was treated with ketoconazole and flucytosine orally, and with ketoconazole percutaneously. On the fortieth day after the first visit, microscopy showed complete recovery of the skin, and mycological examination was negative. This successful case suggested that the combined use of internal and dermatologic medication is effective in treating superficial mycosis, especially cryptococcosis.

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In this paper, we report our dental treatment for malocclusion of the incisors in twelve rabbits and their individual prognoses. We also introduce a safety cover we designed to put around the bar of a dental engine. Four cases out of twelve were very successful, where rabbits which received occlusal correction of the incisors came to have completely normal incisors within three months, needing no further occlusal adjustment. Another four cases were fairly successful, where rabbits which received three-month frequent occlusal correction of the incisors came to have almost normal incisors, only needing a once-a-month occlusal adjustment after the first three months. The other four cases were unsuccessful. The rabbits of this group had a bone screw or plate placed inside the mouth, or had artificial teeth attached. They are still under observation. In daily clinics, short-time reductive procedure for permanently growing incisors without general anesthesia is meaningful because it will make pet owners feel comfortable with bringing their pets frequently. The protective cover we invented enabled us to burnish teeth more safely and quickly than ever without anesthesia, so our invention proved to be useful.

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This is a case of spontaneous closure of a ventricular septal defect (VSD) after being diagnosed by echocardiography in a dog. Holosystolic murmur (grade III of VI) was heard at the 4th right intercostal space of a male cavalier king charles spaniel when he was three months old. Dorsoventral and lateral thoracic radiographs showed a right ventricular enlargement, loss of cranial waist and a slightly increased shadow of peripheral pulmonary vascularity. Echocardiographic examinations revealed a left-to right shunting though a small solitary defect in the membranous septum. At the age of four months, cardiac murmur was inaudible, and a mosaic image depicted by shunting flow could not be seen in the right ventricle on echocardiogram so that the diagnosis of spontaneous closure of a ventricular septal defect was made. The patient has been doing well without requiring any medication since then. In conclusion, echocardiographic follow-ups are considered excellent as an noninvasive method in evaluating pathosis of VSD periodically in dogs.

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We report a successful case of a dog treated for canine insulinoma. The 13-year-old, unspayed, mixed-breed dog presented with ataxia as the main complaint. The dog was suffering from hypoglycemia with concomitant hyperinsulinemia, which suggested the presence of an insulin-secreting tumor. Surgically, an isolated nodular tumor was found in the pancreas, so partial removal of the pancreas was done, and a nearby lesion including an enlarged mesenteric lymph node was also removed. Histopathology confirmed the diagnosis of insulinoma accompanied by metastasis to a regional lymph node. Although the dog showed continuous hypoglycemia even after surgery, clinical signs caused by hypoglycemia have been well controlled for 320 days with medical treatment.

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