The optimal time of initial vaccination with a mild-type live IBD vaccine in chicks with maternally derived antibody (MDA) was studied. The half-life of MDA was 3.46 days, and critical MDA titer to protect from infection with field virus was 1: 28. The protective immunity was acquired 6 days after vaccination, and an MDA titer of 1: 28 interfered with active immunization. If the initial vaccination should be made at age when geometric mean MDA titer lowered to 1: 80, the optimal time (Y) was calculated from age of MDA titration in days (Z) and log10 geometric mean MDA titer (X) of flocks by the following formula; Y=11.49X+Z-21.87.
At 31 days after the 2nd vaccination of porcine epidemic diarrhea virus (PEDV) live vaccine the vaccinated sows were shown to have antibody titers of 1: 4 to 1: 128, and the titers were 1: 4 or 1: 8 at six months after vaccination. Maternally derived antibodies in piglets from the vaccinated sows disappeared around 2 months of age.
Sera collected from pig farms in Tochigi Prefecture were examined for neutralizing antibody against porcine epidemic diarrhea (PED) virus. Antibody was detected in 9 of 34 (26.5%) cities and towns, 13 of 88 (14.8%) farms and 63 of 1, 183 (5.3%) pigs, while no apparent cases suspected of PED were recognized.
From July to December in 1996 at hoggery in Okayama Prefecture, about 270 piglets showed edema of eyelids and nervous symptom about 10 days after weaning and acutely died. Three killed or dead pigs were necropsied, revealing histopathologically fibrinoid and hyaline degeneration of vascular walls in the brain stem and the submucosa of the small intestine. Verotoxigenic Escherichia coli (VTEC) O 139 was isolated from the brain, lymph nodes and intestinal contents. VTEC O139 of the same serotype as isolats from the dead cases was also detected from storage tank and drinking water in the hoggery, and no more outbreaks occurred after chlorinating water and complete sweeping-out and disinfecting of the farmhouses.
A 5.5-month-old male Shih Tzu with the unerupted maxillary deciduous canines and swelling of the alveolar mucosa was shown to have bilateral impacted deciduous canines by X-ray examination. The crown of the left deciduous canine was partially erupted from the jaw bone showing a unilocular radiolucent area around the crown, and a small amount of clear and mucous fluid was obtained by exploratory puncture, suggesting the presence of an odontogenic cyst. The impacted left deciduous canine was extracted and the cyst wall was removed with a curet, resulting in normal eruption of the left upper canine after treatment. Histopathology of the removed specimen revealed a cystic structure lined by the non-keratinized stratified squamous epithelium with bud-like proliferation, and the case was diagnosed as odontogenic eruption cyst.
A 5-year-old mongrel male cat showing swelling of multiple pads with or without hemorrhage, was diagnosed as feline plasma cell pododermatitis by clinical, hematological and histopathological findings. The case was subjected to surgical debridement of the affected metacarpal pads and local injections of prednisolone for 20 days. No recurrence was seen at 20 months postoperation.
A 9-year-old, spayed female Shih-Tzu had vomiting, stranguria and hematuria and abdominal radiography and intravenous pyeliography revealed calculi in the left kidney and abscence of the right kidney. Emergent operation was performed to remove the renal calculi, and postoperatively, genaral physical conditions were well recovered without any significant clinical signs.
Seven of 100 wild boars (Sus sucrofa) captured in Saitama, Gunma and Fukushima Prefectures, Japan, were positive for Sarcocystis cysts by light-or electron-microscopy. Fresh mature cysts from the diaphragm and heart were 450-2, 120×115-140μm in size, and the cyst wall 4 to 6μm thick showed a palisade-like structure. Scanning electron microscorsy revealed mamy villar protrusions 4μm in length and 1μm in width on the cyst surface. Nine or more days after ingestion of the infected boar muscle, two 6-month-old dogs excreted oocysts and sporulated sporocysts 12-13×10μm in size, in the feces. Based upon the Size and fine Structure of cysts and host Specificity, the detected species was identified as S. miescheriama Kuhn, 1865.
Two species of Sarcocystis were detected from the diaphragm muscle of 124 (91.2%) of 136 sika deer, Cervus nippon centralis and Corvus nippon yesoensis, which were captured in Saitama, Gunma and Hokkaido Prefectures, Japan from November, 1994 to January, 1998. The infection rates of one species with the thick (8-10 μm) radialley striated cyst wall (S. sp.1) and the other with the thin (<1μm) smooth wall (S sp.2), were 84.6% and 22.1%, respectively. Cysts of S sp.1 (1, 050-2, 060×60-112μm) provided with finger-like Villar prot trusions (7-9×0.3-0.4μm) on the surface, while those of S sp.2 (680-1, 120×86-132μm) had hair-like protrusions (7-8×0.3-0.4μm). Two each of 6-month-old dogs shed sporulated sporocysts (15-17×10-12μm and 16-17×10-11μm) in the feces 12 and 10 days or later after ingestion of S. sp.1 and S.sp. 2 cysts, respectively.
Hog carcasses skinned by a standing-type skin stripper were examined for microbiological and hog hair contamination. After skinning, the totao viable counts of bacteria were<1-<102CFU/cm2 and no bacteria were detectable from 34 of 54 cases examined. However, microbiological contamination was recognized from dressed carcasses, showing total viable counts of 101-<104CFU/cm2, and 17 of 30 samples showed 102-<103CFU/cm2. By hygienic handling and washing with hot water, microbiological contamination decreased showing the total viable counts of 1-<102CFU/cm2, and the counts were 101-<102CFU/cm2 in 16 of 24 samples. The average number of hog hairs per carcass was 48.8, a significantly lower value (p<0.01) as compared to the values (104.1) of the bed-type skinner carcasses.