Six pigs, 3-or 3.5-month-old, and 4 suckling pigs, 7-day-old, were vaccinated twice with a solubilized Aujeszky's disease virus (ADV) trial vaccine. Two to 4 weeks after the 2nd vaccination, all the vaccinated pigs, together with 4 non-vaccinated control pigs, were exposed to virulent ADV. Two or 4 months after exposure to the challenge virus, all the vaccinated animals, which developed no clinical sings of illness, and the control animals were given prednisolone (1g/day) intramuscularly for 4 or 5 consecutive days. Virus shedding after the prednisolone treatment was detected in one of 10 vaccinated pigs but not in the remaining 9 pigs. On the other hand, the virus shedding from nasal mucus was detected in 3 of 4 non-vaccinated pigs, but not in the remaining pig. Furthermore, all the pigs, which shed ADV, had an obvious increase in neutralizing antibody titer after the prednisolone treatment, whereas the pigs, which did not shed ADV, failed to do so. These results may explain that vaccination with the solubilized ADV vaccine prevents infection of pigs with virulent virus.

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In a swinary in Kagoshima Prefecture, 6 piglets, 46 days old, had diarrhea with a poor appetite, and as a result became too thin. They were treated but no effect was obtained on their conditions. Then, 2 piglets were sacrified at the age of 55 days to evamine the cause of diarrhea.
Hematologically, there were increases in the number of neutrophils, hematocrit value and serum level of total protein. No helminthic eggs were detected as a result of the fecal examination and trichomonads were not isolated from the feces. Bacteriologically, 10⁵cfu/g of Escherichia coli was isolated from the cecum and 10⁸cfu/g from the colon of the two piglets. From the cecum of one, 10³cfu/g of Campylobacter hyointestinalis was isolated. The rota virus antigen was negative in the feces and intestinal mucosa. At necropsy, there were observed numerous white nodes in the epithelium and thickened mucous membrane in the colon and cecum, as well as swelling of the mesenteric lymph nodes. Histologically, degeneration, desquamation and necrosis of the mucous epithelial cells, hyperplasia of intestinal crypts, suppuration and necrosis of submucosa, and numerous trichomonads in intestinal crypts were evident in the colon and cecum. The trichomonads were circular, oval or crescent in shape and had a mean size of 11.0μm long and 3.5, um wide. They were identified as Tritrichomonas suis from their size, positive reaction to PAS and darkbrown staining by the Warthin starry metnods. Electron microscopy revealed that the trichomonads had 3 anterior flagella and an undulating membrane. These results suggest that the present cases occurred in relation to trichomonad infection. Antibodies to trichomonads, which were examined by the indirect immunofluorescent technique on 8 farms, were positive in 6 farms (75.0%) and 17 of 44 pigs (38.6%), suggesting that trichomonads are prevalent on the swinaries to an extensive extent.

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A total of 143 strains of Pasteurella multocida isolated from the nasal cavity and pneumonic lung lesions of swine were tested for antibiotic susceptibility.
Almost all of the isolates were highly susceptible to penicillin (PC), ampicillin (ABPC), tetracycline (TC), oxytetracycline (OTC), chloramphenicol (CP), and thiamphenicol (TP). However, susceptibility of the isolates to aminoglycosides and macrolides was not high. A total of 18 strains (12.6%) were resistant to various antibiotics. Of them, two strains were resistant to six antibiotics (PC, ABPC, TC, OTC, streptomycin (SM) and kanamycin (KM)), one was double (TP and SM), and the others were single (PC, OTC, CP, SM). The frequencies of isolation of resistant strains were higher in the capsular serotype D (27.3%) than in serotype A (9.9%) of isolates, and in the dermonecrotic toxin-positive strains (27.3%) than in negative ones (9.9%, P<0.05).

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A modified EDTA tolerance test was applied to the diagnosis of hypoparathyroidism in a dog with idiopathic hypoparathyroidism, 3 parathyroidectomized dogs and 4 normal dogs.
A 200ml volume of 5% glucose solution supplemented with EDTA-2Na (70mg/kg) andprocaine hydrochloride (4mg/kg) was given intravenously in about 20 minutes. Blood sample were taken just before the infusion, 5 minutes after and 1, 2 and 3 hours thereafter. These samples were analyzed for serum calcium and serum parathyroid hormone (PTH) levels.
The estimated time of recovery of serum calcium in hypoparathyroid dogs took about 3 to 4 hours longer than that in normal dogs. The maximum rise of serum PTH levels was 3.15±0.77 (Mean±SD) times in normal dogs, whereas the serum PTH levels of hypoparathyroid dogs did not rise at all.
Therefore, it was proven that an EDTA tolerance test can be used as a definitive diagnosis of canine idiopathic hypoparathyroidism.

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Cardiazol activated electroencephalograms (EEG) were recorded from four normal dogs. The relationship between clinical features and the appearance of signs of electroencephalographic abnormality was investigated. The EEG seizures were a mixture of spikes, slow waves, and spike-and-slow-wave complexes in the early stage of Cardiazol activation. Following this spike-and-slow-wave complex phase, the EEG revealed persistent and generalized spikes (grand mal phase) and thereafter revealed an inactive phase (resting phase). Clinical manifestations of the seizures consisted of tonic flexion, tonic extension, and clonic convulsion. These motor seizures were in association with changes in the EEG seizures. A typical change in activities of the brain was observed by power spectral analysis. It was concluded that cardiazol activation was a useful technique for reproducing epileptic seizures, and that the activated EEG examination was also useful for clinical diagnosis in epileptic dogs.

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The authors attempted to isolate Streptococcus mutans from oral samples taken from 69 dogs kept indoors. Of them, 37 (53.6%) cases had S. mutans.
Among the 37 strains of S. mutans isolated, 15 strains were identified as serovar c (40.5%) and 4 serovar d (10.8%). The serovar of the remaining 18 strains was not able to be specified.

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