High-resolution ultrasonography of xenografted domestic cat ovarian cortex

Transplantation of ovarian tissue has high potential for female gamete conservation. However, optimal timing of oocyte recovery for in vitro maturation and fertilization is still critical. Therefore the aim of the present study was to use high-resolution transcutaneous ultrasonography to monitor follicular development within xenografted ovarian tissue. Ovarian cortex fragments (n=44) from domestic cats were transplanted into athymic nude rats (n=12). Graft development in the animals was assessed weekly by high frequency ultrasound (10-22 MHz) under two different FSH regimes. Blood collection for serum estradiol determination and vaginal smears were performed simultaneously. The xenografts were removed at different time points according to the ultrasound findings. The survival rate of the transplants 4 weeks after surgery was 54.5% and antral follicular growth was observed within 10 grafts from 5 different hosts (8.6 +/- 6.43 follicles per graft). Early follicle antrums could be detected from 0.4 mm onwards. The growth rate of the antral cavity was calculated from weekly measurements (0.56 +/- 0.44 mm per week). Although vaginal cells and estradiol levels followed a cyclic pattern, no correlation was found between follicular diameter, estradiol and keratinized vaginal cells. We recovered 5, 1 and 4 cumulus oocyte complexes from three different individuals during weeks 19, 21, and 23 respectively. Extrusion of a polar body (1 oocyte) and germinal vesicle break down (7 oocytes) indicated progression of maturation after in vitro culture. We conclude that ultrasonography und provided a reliable method to examine xenograft survival and follicular development within the grafts. Furthermore, this technique is suitable for assessment of the efficiency of hormonal treatment and narrowing of the optimal time frame for oocyte retrieval. To our knowledge, this is the first report of the in vivo development of early antral follicles in mammalian species.     

Clinical features of avian vacuolar myelinopathy in American coots

OBJECTIVE: To characterize clinical features of avian vacuolar myelinopathy (AVM) in American coots. DESIGN: Case-control study. ANIMALS: 26 AVM-affected American coots and 12 unaffected coots. PROCEDURES: Complete physical, neurologic, hematologic, and plasma biochemical evaluations were performed. Affected coots received supportive care. All coots died or were euthanatized, and AVM status was confirmed via histopathologic findings. RESULTS: 3 severely affected coots were euthanatized immediately after examination. Seventeen affected coots were found dead within 7 days of admission, but 5 affected coots survived > 21 days and had signs of clinical recovery. Abnormal physical examination findings appeared to be related to general debilitation. Ataxia (88%), decreased withdrawal reflexes (88%), proprioceptive deficits (81%), decreased vent responses (69%), beak or tongue weakness (42%), and head tremors (31%), as well as absent pupillary light responses (46%), anisocoria (15%), apparent blindness (4%), nystagmus (4%), and strabismus (4%) were detected. Few gross abnormalities were detected at necropsy, but histologically, all AVM-affected coots had severe vacuolation of white matter of the brain. None of the control coots had vacuolation. CONCLUSIONS AND CLINICAL RELEVANCE: Although there was considerable variability in form and severity of clinical neurologic abnormalities, clinical signs common in AVM-affected birds were identified. Clinical recovery of some AVM-affected coots can occur when supportive care is administered. Until the etiology is identified, caution should be exercised when rehabilitating and releasing coots thought to be affected by AVM.     

Prevalence and risk factors for contamination with Listeria monocytogenes of imported and exported meat and fish products in Switzerland, 1992-2000

A total of 2053 import and 164 export samples from 425 production plants were examined over a 9-year period (1992-2000) for the presence of Listeria monocytogenes (L. monocytogenes) in Switzerland. Overall, 282 samples (12.2%) and 85 plants (20.5%) harbored the pathogen. The highest isolation risk was for marinated fish (38%); the lowest was in cured- and dried-meat products.Unconditional fixed-effect logistic regression was used to identify the main hazards associated with the presence of L. monocytogenes. The plant-level model considered potential risk factors for a positive culture operating at the production-plant level by including a random effect of plant and year.Food category was the only significant factor; sampling site, country of origin and season were not significant. Marinated fish was a strong predictor for positive culture, whereas cooked- and cured-meat products were protective. Plant and year effects were significant. Control measures should be focused on specific food items in each production plant.     

Continuous lumbar hemilaminectomy for intervertebral disc disease in an Amur tiger (Panthera tigris altaica)

A 13-yr-old Amur tiger (Panthera tigris altaica) was presented for an acute onset of paraplegia. Spinal imaging that included plain radiographs, myelography, and computed tomography performed under general anesthesia revealed lateralized spinal cord compression at the intervertebral disc space L4-5 caused by intervertebral disc extrusion. This extrusion was accompanied by an extensive epidural hemorrhage from L3 to L6. Therefore, a continuous hemilaminectomy from L3 to L6 was performed, resulting in complete decompression of the spinal cord. The tiger was ambulatory again 10 days after the surgery. This case suggests that the potential benefit of complete spinal cord decompression may outweigh the risk of causing clinically significant spinal instability after extensive decompression.     

Selenium balance in the adult cat in relation to intake of dietary sodium selenite and organically bound selenium

The response of cats to dietary sodium selenite (Na(2) SeO(3)) and organically bound selenium was studied in two separate studies with four cats per treatment and three levels of selenium supplementation (targets 1.0, 1.5 and 2.0 μg/g DM) for each Se source. Whole blood and plasma selenium concentrations and glutathione peroxidase (GPx) activity were determined at 7-time points across the 32-day study. Faeces were quantitatively collected during the last 8 days and urine was collected daily during both studies. The basal diet used had a low apparent faecal selenium absorption of 25.3 ± 3.0%. Daily faecal and urinary selenium excretion increased linearly with increasing selenium intake for both Se sources. Urinary selenium concentration of the cats fed the supplemented diets increased rapidly (～2 days) and remained constant throughout the remainder of the study. Apparent faecal selenium absorption was high for both selenium sources (73.2% and 80.0%). Plasma, and to a lesser extent, whole blood selenium concentrations increased in a dose-dependent manner with supplementation. Whole blood and plasma GPx activity were highly variable and showed a variable response to dietary selenium intake. Cats closely regulate selenium homeostasis through increasing urinary excretion whilst faecal absorption remains unaffected.     

Cooperating with industry to teach food-animal medicine

Cooperative programs with agribusiness offer opportunities for colleges of veterinary medicine to expand their instructional programs in agricultural practice. Agribusinesses associated with livestock agriculture recognize the importance of veterinary medicine in maintaining a vibrant and successful industry. Stewardship of corporate support involves close communication with advocates within the companies, providing them with documentation of the potential effects of corporate investments. This article describes the creation of the Michigan State University (MSU) Training Center for Dairy Professionals, a key aspect of which was the identification of innovative and productive areas of mutual interest and benefit. In addition to supporting the dairy industry by training veterinary students, the program offers specific benefits to investors, including the use of MSU facilities and direct participation in veterinary instruction.     

The 2006 American Association of Feline Practitioners Feline Vaccine Advisory Panel report

Vaccination is a medical procedure, and the decision to vaccinate should be based on a risk-based assessment for each cat and each vaccine.