New USB-based 3D digital echo sounder system for mapping and assessing fish and aquatic plants

A recently developed echo sounder with a global positioning system (GPS) receiver can display both the boat position and echo gram. However, this information is displayed in different views. In this paper, we present a new digital three-dimensional (3D) echo sounder system comprising a traditional analog echo sounder, GPS receiver, notebook personal computer (PC), and a low-cost, compact, self-developed universal serial bus (USB)-based analog-to-digital (A/D) converter board. Multiple echo views can simultaneously display various desired targets more clearly than the view in a traditional analog echo sounder. The newly developed analysis software can precisely extract the information related to bottom depth, plants, and fish schools from the echoes. By combining the acoustic and position data, the system can map both the fish and plant echoes on the 3D sea bed generated from the extracted bottom depth. This system has been proved to be useful in observing the 3D and wide-area distribution of both fishes and aquatic plants and in studying habitat parameters in aquatic ecosystems. A notebook PC equipped with the self-developed USB-based A/D converter board is capable of transforming any traditional analog echo sounder into a high-performance 3D digital echo sounder.     

Effects of growth factors on development of fetal islet B-cells in vitro

To investigate the role of growth factors (epidermal growth factor [EGF], betacellulin, and activin A) in the development of islet B cells of rat fetal pancreatic explants in vitro, pancreases from rat fetuses at day 18 of gestation were cultured for 96 hr, with or without these growth factors. Culture medium was changed every 24 hr, and the level of insulin released in the culture medium was measured. After 72 hr of culture, pancreases were examined histologically. As a result, EGF promoted cell proliferation, but reduced B cell volume. Whereas, betacellulin and activin A inhibited cell division, but promoted increased B cell volume and insulin secretion, especially activin A, which stimulated insulin release in a time dependent manner. These results suggest that EGF, betacellulin, and activin A promote pancreatic cell proliferation, islet B-cell differentiation, and islet B-cell differentiation and functional maturation, respectively, and that EGF, betacellulin, and activin A, in this order, regulate islet B-cell neogenesis.     

Glomus tumor of the liver in a cow

An 11-year-old Holstein-Friesian cow exhibited anorexia and jaundice. A large mass was found in the liver during necropsy. Macroscopically, the mass was composed of dark red multilobular tissue and a centrally located abscess, which was connected to the hepatic duct. Histologically, the mass consisted of proliferation of small neoplastic cells and was demarcated from the hepatic parenchyma by a thick region of granulation tissue. The neoplastic cells were predominantly arranged in solid sheets, but they also formed blood-filled cancellous structures, and proliferating foci were seen around blood vessels. Periodic acid-Schiff reaction demonstrated that a fine basement membrane-like structure surrounded the neoplastic cells. Immunohistochemically, the neoplastic cells were positive for vimentin and alpha smooth muscle actin and negative for cytokeratin, factor VIII-related antigen, chromogranin and desmin. Based on its histopathological features, the hepatic neoplasm was diagnosed as a primary glomus tumor. This is the first report about a primary glomus tumor of the liver in a cow.     

Detection of the nonsense mutation of OPA3 gene in Holstein Friesian cattle with dilated cardiomyopathy in Japan

Bovine dilated cardiomyopathy (DCM) is an autosomal recessive genetic disorder causing congestive heart failure and subsequent death. Recently, a nonsense mutation c.343C>T in the bovine optic atrophy 3 (OPA3) gene had been reported to cause the DCM in Holstein cattle in Switzerland. However, the mutation has not been confirmed in bovine DCM outside Switzerland. Nine Holstein Friesian cows that were macroscopically and histologically diagnosed with or suspected of DCM and 12 control cows kept in Japan were tested for the mutation. The mutation surrounding OPA3 DNA fragment was amplified by PCR and subjected to direct sequences. The homogeneous c.343C>T mutation was proved to occur in all the affected cows and not in the control cows. The present study is the first report of the mutation in the DCM affected cows outside Switzerland.     

Optic pathway degeneration in Japanese black cattle

Degeneration of the optic pathway has been reported in various animal species including cattle. We experienced a case of bilateral optic tract degeneration characterized by severe gliosis in a Japanese black cattle without any obvious visual defects. To evaluate the significance, pathological nature and pathogenesis of the lesions, we examined the optic pathway in 60 cattle (41 Japanese black, 13 Holstein and 6 crossbreed) with or without ocular abnormalities. None of these animals had optic canal stenosis. Degenerative changes with severe gliosis in the optic pathway, which includes the optic nerve, optic chiasm and optic tract, were only observed in 8 Japanese black cattle with or without ocular abnormalities. Furthermore, strong immunoreactivity of glial fibrillary acidic protein was observed in the retinal stratum opticum and ganglion cell layer in all 5 cattle in which the optic pathway lesions could be examined. As etiological research, we also examined whether the concentrations of vitamin A and vitamin B12 or bovine viral diarrhea virus (BVDV) infection was associated with optic pathway degeneration. However, our results suggested that the observed optic pathway degeneration was probably not caused by these factors. These facts indicate the presence of optic pathway degeneration characterized by severe gliosis that has never been reported in cattle without bilateral compressive lesions in the optic pathway or bilateral severe retinal atrophy.     

Analysis of the bone morphogenetic protein 6 gene promoter region in young beef cattle affected by enzootic bovine leukosis

Enzootic bovine leukosis (EBL) is typically observed in cattle over 3 years old. However, some cases of EBL onset in young beef cattle have been reported in Japan. The mechanism for early EBL onset is unclear. In Japan, beef cattle are given large amounts of concentrated feed with low vitamin A. Bone morphogenetic proteins (BMPs) are regulators of cell proliferation, differentiation, and apoptosis, and thought to represent one of the key players in tumor malignancy. The purpose of this study was to evaluate the differences in BMP-6 methylation status between EBL beef cattle under 3 years old and other cattle. We investigated the methylation status of the BMP-6 promoter region in 32 EBL beef cattle under 3 years old. We also compared the methylation status of EBL dairy cattle to that of healthy cattle. Median methylation rate of the BMP-6 promoter region in EBL beef cattle under 3 years old was 8.9%, which was significantly higher than that of other groups. Hypermethylation of the BMP-6 promoter region might contribute to early onset of EBL in beef cattle under 3 years old, and animal feeding management practices specific to beef cattle may affect the methylation status of the BMP-6 promoter region.     

Successful blastocyst production by intracytoplasmic injection of sperm after in vitro maturation of follicular oocytes obtained from immature female squirrel monkeys (Saimiri boliviensis)

Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys.     

五氟磺草胺在稻田中的消解动态及残留特性

建立了超高效液相色谱-质谱联用检测五氟磺草胺在水稻植株、稻田土壤、田水和糙米中残留的分析方法,结合田间试验研究了五氟磺草胺在稻田环境中的消解及残留特性,并对稻米中五氟磺草胺残留的膳食暴露进行了初步评估。结果表明:在0.005~0.5 mg/L范围内,五氟磺草胺的质量浓度与对应的峰面积间呈良好线性关系,检出限（LOD）为0.001~0.002 mg/kg,定量限（LOQ）为0.003~0.005 mg/kg。在0.005~0.5 mg/kg添加水平下,五氟磺草胺在水稻植株、稻田土壤、田水和糙米中的平均回收率在89%~106%之间,相对标准偏差在2.8%~8.5%之间。浙江、福建和黑龙江2年3地的田间试验表明:0.025%五氟磺草胺颗粒剂在水稻植株、稻田土壤和田水中的消解半衰期分别为1.5~3.3,3.0~4.7和1.6-3.0 d,说明该药剂在稻田环境中消解速率较快。以五氟磺草胺有效成分含量37.5和56.3 g/hm2分别施药1次,于水稻成熟期采样检测,发现其在糙米中的残留量低于0.005 mg/kg,表明其膳食摄入风险很低,该研究结果可为五氟磺草胺风险评估提供一定参考。