Death in four RHDV2-vaccinated pet rabbits due to rabbit haemorrhagic disease virus 2 (RHDV2).

OBJECTIVES: To create awareness of single RHDV2 infections and cases of death despite immunisation with RHDV2-specific vaccine. MATERIALS AND METHODS: Retrospective case series of four companion rabbits. Patient signalment, vaccination history, pathology and molecular examinations were obtained from the medical records. RESULTS: The animals died peracutely or with nonspecific symptoms like apathy and inappetence. Pathological examination indicated and molecular biological findings confirmed RHDV2 infection in four animals. Several partner animals died at the same time under the same circumstances. CLINICAL SIGNIFICANCE: This is the first report of fatalities in RHDV2-vaccinated companion rabbits due to rabbit haemorrhagic disease virus 2 infection with documented case and vaccination history. Veterinarians should be aware of possible single fatal RHDV2 infections despite vaccination, should initiate the clarification of suspected cases and inform vaccine manufacturers and competent authorities.

Genital Tract Pathology in Female Pet Guinea Pigs (Cavia porcellus): a Retrospective Study of 655 Post-mortem and 64 Biopsy Cases.

Disorders of the female genital tract are among the most common disorders in pet guinea pigs (Cavia porcellus); however, knowledge of many aspects of these disorders is sparse, especially regarding their incidence and age distribution. Ovarian cysts, as the most common genital tract disorder in guinea pigs, have been investigated in detail; however, information on the nature of these cysts is inconsistent. The present study reviewed genital tract disorders occurring within 655 full post-mortem examinations of intact female pet guinea pigs and 64 female genital tract biopsies examined over a 22.5 year period. Age distribution was determined from 550 post-mortem examinations of animals of known age. Genital tract disorders were found in 295 post-mortem examinations (45.0%) in animals with a median age of 52 months. Additionally, disorders were found in all genital tract biopsy samples from guinea pigs with a median age of 48 months. The incidence of genital tract diseases increased from 1.5% in guinea pigs ≤6 months of age to up to 77.8% in animals >6 years of age. Ovarian cysts were the most common genital tract disorder, found in 245 of the 655 post-mortem cases (37.4%) and 38 of 43 ovarian biopsy samples (88.4%). The incidence of ovarian cysts increased with advancing age, reaching 75.6% in animals >6 years. In 119 cases, histopathology and immunohistochemistry confirmed cystic rete ovarii as the only cyst type. A Fallopian tube adenoma was found in a single case, so disorders of the Fallopian tube should be considered rare. Uterine disorders were diagnosed in 17.4% of the post-mortem examinations and 98.1% of uterine biopsy samples. Uterine neoplasia, hyperplasia and inflammation were common, but occurred at different ages. The incidence of uterine neoplasia and hyperplasia was higher in older animals (>15% in guinea pigs >6 years), while the incidence of uterine inflammation was the highest (17.9%) in animals aged 7-12 months. An association between ovarian cysts and uterine neoplasia or hyperplasia was not evident. Vaginal disorders were rare and included leiomyoma, polyps and vaginitis.

Genital Tract Pathology in Female Pet Rabbits (Oryctolagus cuniculus): a Retrospective Study of 854 Necropsy Examinations and 152 Biopsy Samples.

Genital tract disorders, especially uterine disorders, are the most common conditions of the female pet rabbit (Oryctolagus cuniculus); however, there have been few large studies of diseases of the female genital tract of this species. The present study examined diseases of the ovaries, Fallopian tubes, uterus and vagina, retrospectively over a period of 22 years, and included 854 full post-mortem examinations of female pet rabbits and 152 female genital tract biopsy samples. The age distribution of uterine neoplasia, endometrial hyperplasia and uterine inflammation was determined in the post-mortem cases. Uterine disorders were a common finding, occurring in 26.8% of all full necropsy examinations and in almost all genital tract biopsy samples. Uterine tumours (n = 205) were the most common uterine pathology, with adenocarcinoma being the most frequent tumour type. Metastasis was found in 46.2% of rabbits with uterine adenocarcinomas diagnosed at post-mortem examination, with metastatic spread to the lung occurring in 79.1% of these animals. The second most common uterine pathology was endometrial hyperplasia, which was glandular-cystic in most cases. The incidence of uterine tumours and endometrial hyperplasia increased with age, while endometrial hyperplasia was found more commonly in slightly younger animals. In contrast, uterine inflammation, the third most common finding, was found predominately in young to middle-aged rabbits. Ovarian disorders were found rarely at post-mortem examinations (3.3% of all animals), but comprised 16.9% of biopsy samples. Of these, ovarian cysts, especially follicular cysts, and secondary tumours were found most frequently. Disorders of the Fallopian tube and the vagina were found in <1% of cases and should be considered rare.

General anesthesia increases temporal precision and decreases power of the brainstem auditory-evoked response-related segments of the electroencephalogram.

BACKGROUND: Brainstem auditory-evoked responses (BAEP) have been reported to be unchanged in the presence of drugs used for induction and maintenance of general anesthesia. The aim of this study was to investigate if the signal segments after the auditory stimulus that are used to average the evoked response change under the influence of general anesthesia. METHODS: BAEPs of 156 patients scheduled for elective surgery under general anesthesia were investigated. Anesthetic regimen was randomized as a combination of one of four hypnotic drugs supplemented by one of four opioids. Signal segments after the auditory stimulus were obtained at six different periods of anesthesia. Power and phase properties of wavelet-filtered single-sweep auditory-evoked activity accounting for the waveform of the averaged BAEP wave V and the stability of amplitude and latency of the averaged BAEP wave V over periods were analyzed. RESULTS: Amplitude and latency of wave V change slightly with no significant difference between the periods. During anesthesia, however, the power of single sweeps is significantly reduced, whereas phase-locking properties of the according signal segments are significantly enhanced. This effect is independent of the anesthetic or opioid used. CONCLUSIONS: General anesthesia affects phase and power of the segments of the electroencephalogram related to BAEP wave V. This study's results support the idea that temporally precise responses from a large number of neurons in the brainstem might play a crucial role in encoding and passing sensory information to higher subcortical and cortical areas of the brain.