Because they are a major source of virus spread in a herd, cattle persistently infected (PI) with the bovine viral-diarrhea virus (BVDV) must be identified and removed. PI cattle generally show various clinical manifestations and are often identified on the basis of mucosal lesions. Some, however, demonstrate no mucosal disease. The present study involves surveillance of BVDV infection in diseased cattle. Examinations for persistent infection were performed on 157 head of cattle demonstrating such clinical manifestations as stunted growth, diarrhea, and pneumonia and others failing to respond to treatment. Of 157 animals demonstrating clinical manifestations, 27 (17.2%) were identified as PI. Next, 14 head of cattle with the same pedigrees as the PI animals but demonstrating no clinical manifestations were examined; 4 of them were identified as PI. It is therefore practically impossible to detect all PI cattle on the basis of clinical manifestations because some demonstrate none at all. Consequently, to determine disease prevalence, examining the whole herd is more important.
Concentrations of serum amyloid A protein (SAA) in serum and milk from healthy cows and cows with subclinical mastitis were measured. In addition, we investigated relations among milk SAA concentration, somatic cell count (SCC), modified California mastitis test (MCMT) scores and bacterial species isolated from milk. There were no differences in serum SAA concentrations between healthy cows and cows with subclinical mastitis. Mean concentrations of milk SAA for each group diagnosed with MCMT were 8.3±13.8μg/ml for negatives, 25.1±26.1μg/ml for repeat examinations, 32.2±65.2μg/ml for suspicious cases and 168±225.2μg/ml for positives. Values for the negative group were significantly lower than those for the other three groups (P<0.01) and the values for the positive group were significantly higher than those for the other three groups (P<0.05). The mean milk-SAA concentration from which Staphylococcus aureus or Streptococcus agalactiae was isolated was significantly higher than those from which Corynecabterium bovis or coagulase-negative staphylococci were isolated. Furthermore there was a significant correlation between the concentration of milk SAA and SCC (r=0.862, P<0.01). These results suggest that concentration of milk SAA rises in subclinical mastitis cases and that the rise may depend on the severity of tissue damage caused by differences in the infecting bacterial species. They also suggest the possibility of SAA production in mammary glands.
Immunological examination of two dogs (flat-coated retrievers) diagnosed as lymphocytic- plasmacytic gonarthritis revealed a T-cell subset imbalance in the knee joints and increased activity of transforming- growth factor-β1 (TGF-β1) as a Th3 cytokine. This finding suggests that immune abnormality mediated by TGF-β1 may play a part in the development of this disease.
A ten-year-old female domestic shorthair cat was referred to the Azabu University Teaching Hospital with a four-week history of episodic syncope. Electrocardiography revealed Adam-Stokes syncope caused by a paroxysmal third-degree atrioventricular block. A permanent pacemaker implantation was performed to prevent further episodes. Inappropriate pacing like spikes on T, which might cause critical arrhythmias, was noticed immediately after implantation. Refractory-period reduction to minimize the likelihood of noise reversion during tachycardia, selection of bipolar pacing, and sensitivity adjustment eliminated the pacing problem. Nine months after the implantation, no further abnormal pacing had occurred.
Histopathologically, a large mass encountered in a unilateral ovary of a slaughtered sow consisted of blood vessels of various sizes and shapes and abundant fibrous tissues. Blood-vessel endothelial cells were well differentiated and positive for Factor VIII related antigens. Ovoid to spindle-shaped cells positive for the anti-human smooth-muscle actin antibody had proliferated diffusely or compactly around the vessels. The tissues contained scattered, medium-sized blood vessels with layers of smooth muscle fiber. Organized thrombi were frequently encountered. On the basis of these findings, the case was diagnosed as an ovarian vascular hamartoma.