Pathological and pathogenic examinations were carried out on three heifers suffering severe respiratory disease on a dairy farm. Extensive fibrinonecrotic inflammation was evident in the respiratory mucosa from the nasal cavity to the lung, nonsuppurative inflammation was found in the trigeminal ganglia, pons and medulla oblongata, and the presence of eosinophilic intranuclear inclusion bodies was detected in the laryngeal glands. Bovine herpesvirus type 1 (BHV-1) antigens and herpesvirus particles were detected in these lesions, and BHV-1 was isolated from the nasal swabs. The lesions in the brain stem were confined to the nuclei associated with the trigeminal nerve tract. The results indicate that the virus produced both lesions in the respiratory mucosa and central nervous system, and suggest that the virus might have reached the brain stem along the trigeminal nerve tract as the predominant route.
Eighty-seven (31%) of 290 cows suffered severe pneumonia on a dairy farm in Iwate Prefecture in March 2005. Thirteen of 17 deceased cows were in the early lactating period and were housed in a shed with free stalls. Pathological and etiological examinations of four dead animals revealed necrotic bronchopneumonia with Mannheimia haemolytica antigen as well as interstitial emphysema and syncytium formation in the lungs. M. haemolytica serotype 6 was isolated from the pulmonary lesions and bovine respiratory syncytial (BRS) virus gene was detected by PCR from the nasal swabs. A significant increase in serum antibody titers against M.haemolytica and BRS virus was found in other affected cows during the epidemic. These results suggest that feeding in loose housing systems and BRS virus infection could have been linked with the outbreak of the disease.
To assess the relationship between the grade of heart failure and blood pressure, 89 healthy dogs and 72 dogs with untreated mitral regurgitation (MR) were compared. Dogs with MR are divided into four groups by NYHA grade. For control, healthy dogs were divided into age-matching four groups. The followings are compared: heart rate, systolic blood pressure, mean arterial pressure and diastolic blood pressure. The results showed that as the NYHA grades rise, so do systolic blood pressure, mean arterial pressure and diastolic blood pressure.
A five-year-old male Boston terrier was presented to the hospital with chronic diarrhea. Various medical and endoscopic examinations suggested that the case was an inflammatory bowel disease. Immunosuppressive therapy based on prednisolone was effective in stopping the clinical symptoms. But the symptoms relapsed after the prednisolone dose was reduced. Subsequently, treatment with prednisolone and cyclosporine was performed, but improved efficacy was not observed. When the concomitant drug was changed to methotrexate (intramuscular) from cyclosporine, a gradual decrease in the prednisolone dose was possible without a relapse in the symptoms. A favorable prognosis was achieved also with oral administration of methotrexate.
At the recommendation of the World Health Organization, preventative measures have been taken for canine infections with the rabies virus and outbreaks have been eliminated by maintaining vaccine coverage of more than 70% in susceptible areas. Recently, Coleman et al. reported that the standard estimation of vaccine coverage, namely the critical percentage (pc), for the prevention of rabies outbreaks among the dog population is 39-57%, using regression analysis of outbreaks in the United States, Mexico, Malaysia and Indonesia. Additionally, the estimated vaccine coverage with 95% confidence is 55-71%, and outbreaks of rabies infections in dogs can be discouraged by vaccine coverage of more than 70% with a 96.5% probability. However, additional actions are necessary for complete prevention and elimination of rabies outbreaks in the dog population, although statistically outbreaks in dogs may be discouraged with 39-57% pc. Consequently, in cases of vaccine coverage of less than 70%, additional actions are helpful for controlling infections in dogs and for reducing the risk of infection.