A phenotypic study of murine oocyte death in vivo

Most studies of oocyte apoptosis have been performed in vitro and have employed the method of artificial induction of apoptosis by an anti-cancer agent. However, the process of oocyte death in vivo has not been clearly identified. To investigate the death process in unfertilized oocytes in vivo, we examined the cytochemical change of oocytes collected by oviduct flushing at various intervals after hCG injection. At each collection time, the collected oocytes were phenotypically classified under the microscope into four groups: single-cell oocytes (non-activated and without a nucleus and cytokinesis), activated oocytes (single-, 2- or 4-cell with a nucleus), fragmented oocytes, and dead oocytes. The number of single oocytes decreased and dead oocytes increased with the lapse of time, but the number of activated oocytes or fragmented oocytes did not. Also, most of the dead oocytes observed were single cell. At each time point, single oocytes were stained with anti-tubulin antibody to examine their spindle status. At 24 h after hCG injection, all ovulated oocytes had a normal bipolar spindle, while at 64 h all single-cell oocytes had no spindle. From these observations, we concluded that most oocyte deaths in vivo occur in the single oocyte stage, not in activated or fragmented oocytes.     

Medial canthoplasty for epiphora in dogs: a retrospective study of 23 cases

The medical records of 23 dogs that underwent medial canthoplasty for treatment of epiphora were reviewed. The most prevalent breed encountered was the shih tzu. Other affected breeds included the Pekingese, Maltese, toy poodle, and pug. All dogs had epiphora associated with medial canthal trichiasis and/or entropion. Other ocular abnormalities included conjunctivitis, keratitis, pigmentary keratitis, corneal ulceration, globe prolapse, and nasal fold trichiasis. After medial canthoplasty, the epiphora resolved in all dogs.     

Acquired cervical syringomyelia secondary to a brainstem meningioma in a maltese dog

A 15-year-old female maltese was referred to us because of a 3-month history of ataxia, circling, and acute blindness. A mass was noted in the brainstem on brain magnetic resonance images. A cerebellar herniation was also detected on T1-weighted sagittal images. The lateral, third and fourth ventricles and central canal of the cervical spinal cord were enlarged. Based on diagnostic imaging findings, cervical syringomyelia secondary to a brainstem tumor was suspected. The clinical signs were controlled well by lomustine and the dog survived for 8 months after the initial diagnosis. The mass was diagnosed as a meningioma based on histopathological findings. This report describes the clinical findings and imaging characteristics of an acquired syringomyelia resulting from a brainstem meningioma.     

Development and characterization of mouse monoclonal antibodies reactive with chicken CD83

This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein containing the extracellular region of chCD83 was expressed in Chinese Hamster Ovary (CHO) cells and isolated from the spent cell culture medium by protein G affinity chromatography. The extracellular region of the chCD83 protein was purified and used to immunize mice. A cell fusion was performed, from which 342 hybridomas were screened for mAbs to chCD83. Two mAbs, chCD83-159 and chCD83-227, stained the greatest percentage of chCD83-transfected CHO cells and were selected for further characterization. By flow cytometry, both mAbs reacted with a chicken macrophage cell line, HD11. Both mAbs also recognized a single 53 kDa protein on Western blots of lysates from lipopolysaccharide-stimulated spleen mononuclear cells or unstimulated HD11 cells. Immunostaining of chicken secondary lymphoid organs identified chCD83(+) cells with morphologic and subtissue localization properties comparable to mammalian DCs. In vitro stimulation of spleen mononuclear cells with concanavalin A (Con A) decreased the percentage of chCD83(+) cells compared with cells treated with medium alone. Interestingly, spleen cells treated with Con A in the presence of chCD83-227 mAb exhibited decreased percentage of MHCII(+) cells compared with cells treated with an isotype-matched negative control mAb. These chCD83 mAbs may be useful for future investigations of chicken immune cell maturation and mechanisms of action.     

Magnetic resonance imaging findings of hepatic encephalopathy in a dog with a portosystemic shunt

A 6-year-old ShihTzu presented with tonic-clonic cluster seizure. T2-weighted magnetic resonance (MR) images showed bilateral diffuse hyperintense lesions at the cerebral cortex with enlarged sulci. Computed tomography revealed a portosystemic shunt (PSS) and azygos continuation. Based on the clinical signs, blood examinations and diagnostic images, the dog was diagnosed with hepatic encephalopathy secondary to PSS. The neurologic signs were gradually improved after medical therapy for hyperammonemia. This is the first report of hyperintensity of the cerebral cortex on T2-weighted MR images associated with acute hepatic encephalopathy in a dog.     

Vertical Transmission of Brucella abortus Causes Sterility in Pregnant Mice

The mechanisms of abortion and sterility induced by bacterial infection are largely unknown. In the present study, we found that Brucella abortus, a causative agent of brucellosis and facultative intracellular pathogen, caused sterility in pregnant mice. We have recently established a mouse model for abortion induced by B. abortus infection and high rates of abortion are observed for bacterial infection on day 4.5 of gestation, but not for other days. Infected newborn (first generation) mice showed poor growth compared with uninfected newborn mice and bacterial replication in the spleen of the former was observed over a long period. When infected first generation female mice were mated to infected first generation male mice, the number of fetuses was significantly less than that in uninfected first generation mice. These infected second generation mice also showed poor growth. These results suggest that vertical transmission of B. abostus causes sterility in pregnant mice and our mouse model would be useful for the investigating of brucellosis.     

The effects of replacement of antibiotics with by‐products of oriental medicinal plants on growth performance and meat qualities in fattening pigs

The effect of by‐products of oriental medicinal plants (OMP; T1) containing 0.03% herb extracts (T2) or 0.1% aminolevulinic acid (T3) on the production performance of swine during the finishing period and on its meat quality were investigated. No significant differences were found in the weight gain, feed intake and feed conversion rate among the tested groups (P > 0.05). But the treated group showed higher (P < 0.05) moisture and ash and lower protein than the control group. The T3 group showed a lower meat cholesterol content (38.42 mg/100 g) compared to the other groups (P < 0.05). The vitamin E content of the muscle in the treated groups was higher compared to the control group. No antibiotic content was detected in all treated and control samples. The values of the volatile basic nitrogen (VBN) and thiobarbituric acid reactive substance (TBARS) of the treated groups were significantly lower (P < 0.01) than the control group. The treated groups had significantly better (P < 0.05) sensory‐test scores for color, flavor, off‐flavor and total acceptability compared to the control group.