A male Holstein calf (2-month-old) with ataxia and dysstasia was autopsied and examined by histological, immunohistochemical and ultrastructural methods. The central nervous system showed extensive spongiosus at junctions of the gray and white matters. Immunohistochemically, the walls of vacuoles constituting the spongiosus were positive for anti-myelin basic protein. Electron microscopy revealed vacuoles that had formed by splitting of the myelinic intraperiod line. The present case was thus diagnosed as spongiform myelinopathy of the central nervous system.
Outbreaks of swine Influenza occurred on 2 pig-farms in Nagasaki Prefecture during the 1989-1990 period. Two hemagglutinating viruses were isolated from nasal swabs of affected pigs and identified antigenically as reassortants of the influenza virus having the hemagglutinin subtype 1 (H1) and neuraminidase type 2 (N2). Serological tests indicated significant increases in hemagglutination inhibition (HI) and neuraminidase inhibition (NI) antibody titers in convalescent sera against the isolates of the influenza virus. A serological survey was conducted using 1, 512 sera from pigs raised on other farms in the prefecture; 31.6% of the swine had the HI antibody to subtype H1 and 29.1%, the HI antibody to subtype H3 of the influenza virus. Antibodies against H1 and N2 antigens of the reassortant viruses were shown present in 12% of the swine. The present results suggest that H1N2 type influenza virus may possibly be spreading among pigs in Nagasaki Prefecture.
The authors reported that K antigen formation of sulfamonomethoxine (SMMX)-resistant Bordetella bronchiseptica is inhibited by SMMX in vitro. The present study was conducted to determine whether inhibition occurs also on the pig's concha nasalis in vivo, using experimentally infected pigs. SMMX in form of a feed added at the rate of 500 ppm was administered consecutively from one day before bacterial inoculation to the day of autopsy, which was performed 11 and 25 days after bacterial inoculation. The SMMX-administered group showed distinct inhibition of bone atrophy of the concha nasalis (AR lesion) both macroscopically and electron microscopically, in contrast to the control group. Decrease in viable cell count of B. bronchiseptica in the concha nasalis was noted in the former group. The serum agglutination titer in the former group decreased to a low value. K antigen formation of SMMX-resistant B. bronchispetica would thus appear to be inhibited in the presence of SMMX on the pig's concha nasalis, leading to inhibition of AR lesions.
In Kagoshima Prefecture, 210 calf congenital abnormalities were observed from June 1987 through May 1992. Abnormalities in 4 calves obviously differed from Akabane disease. The calves were born in the northwest area of Kagoshima from February to April 1991 and in March 1992. Macroscopically, the dilated lateral ventricle and hydranencephaly were evident in all the animals. Cerebellar hypoplasia and cerebellar defect were seen. Some showed arthogryposis or gelatinized-yellowish skeletal muscle of the extremitas. Histopathologically, nonpurulent encephalitis in the cerebrum was demonstrated. The cerebellar structure was remarkably disordered. Loss or marked decrease in the nerve cells in the spinal ventral-horn and runt muscle of the extremitas were apparent. Antibody to Aino virus only was detected in the calves by the neutralization test. In the northwest area, Aino virus was shown most active between mid-October and early November in 1990 and 1991. Antibody-positive rates were higher than those of other areas. The present results suggest Aino virus infection of calves and the possibility that Aino virus may be an etiologic agent of these congenital abnormalities.
Thirty-day-old specific pathogen-free chickens were inoculated with avian reovirus (ARV) via the footpad (FP) and FP lesions were examined histopathologically. A comparison was made with lesions of the gastrocnemius tendon. In FP, edema and cellular infiltlation consisting of heterophils and mononuclear cells were observed 2 days after inoculation. These changes peaked 4-6 days after inoculation. Later, edema gradually disappeared with change in the swelling index. Lesions of the gastrocnemius tendon peaked 6-8 days after inoculation, and were milder than those of FP. Both lesions were similar qualitatively. The FP lesion would thus appear usable as an index of the severity of ARV infection, in place of the results of the gastrocnemius tenosynovitis examination.
A simple method for detecting Babesia gibsoni in blood was established. Red blood cells infected with B. gibsoni (treated with EDTA-2K) were collected by centrifugation and resuspended in a 10-fold volume of physiological saline. The suspension was transferred to a syringe, passed through a 3μm Millipore filter and lysed. The precipitate thus obtained was smeared on a slide glass, stained with Giemsa's solution and examined by microscopy. Protozoae were detected consistently in all smear samples. No parasite, however, could be found in any of whole blood smears.
Three % N-acetylcysteine collyrium (ACET: collagenase inhibitor) was evaluated for its effectiveness in treating corneal diseases (injury keratitis, keratoconjunctivitis sicca, corneal ulcer, etc.) in dogs. One or two drops of ACET were administered five or six times a day as a rule. Other drugs which would possibly influence assessment of effects were not administered with ACET. Seventy-one dogs were used for this assessment and 82 for the safety testing of ACET. Injury keratitis (30 cases) and corneal ulcer (40 cases) were the main diseases in the former. Beneficial effects were recognized in 63 (88.7%) of the 71 dogs. No animals became worse and no side effects were observed. Sixty-one (85.9%) of the 71 dogs showed improvement. ACET would thus appear to be a safe and reliable drug for treating corneal epithelium diseases in dogs.
An 8-year-old female Yorkshire terrier(Case 1)and a 14-year-old female Shetland sheepdog(Case 2)were admitted to the authors' Veterinary Clinic because of persistent vomiting after food intake. Both animals became weak after being treated conservatively without response. In both cases, pyloric stenosis was suspected by contrast radiography, and exploratory laparotomy was performed. In Case 1, the pyloric lumen was narrowed with cauliflower-like tissue. In Case 2, a globe-shaped swelling was observed on the serosa side. It was felt that these abnormal structures were tumors and the cause of the pyloric stenosis. From histopathological examination of the biopsytissue, the lesions of Cases 1 and 2 were diagnosed as adenocarcinoma and lymphosarcoma, respectively. Canine gastric tumors are rare and the noticeable symptoms are not characteristic. Thus, it is difficult to detect these conditions at an early stage. However, it suggests that cases of chronic voimting in older dogs should be carefully investigated for gastric tumors.
An analytical method for measurement of the synthetic antibacterials, difrazon and morantel, in pork was developed. The study was performed under the following conditions: a Finepak SIL C 18S was used as the analytical column, and the HPLC mobile phase consisted of 40%(v/v) acetonitrile and 0.1%(v/v) orthophosphoric acid in a mixture of 5 mM 1-hexanesulfonic acid sodium salt, pH 2.65. The antibacterials were detected at 380 nm for difurazon and 320 nm for morantel. The calibration curves for authentic difurazon and morantel were linear in the range of 5 to 200 ng. The detection limits were one ng for both antibacterials. The recovery rates of the authentic antibacterials added to pork or kidney tissue were more than 90%.