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61.
Eastern little tuna (ELT, Euthynnus affinis) is expected to see use as a novel aquaculture species due to its rapid growth and high economic value. In this study, closing of the complete life cycle of ELT in land‐based tanks was successfully carried out. Seed production of a first generation (F1) derived from wild‐caught ELT broodstock was conducted in 2010, 2011 and 2012. Survival percentages of F1 ELT at 365 days post hatching for the 2010, 2011 and 2012 year classes were 0.9%, 0.4% and 6.3% respectively. On average, F1 ELT were approximately 40 cm in total length and weighed 1500 g by the time they reached 1 year of age. Successful artificial induction of spawning was achieved in 1‐year‐old F1 ELT using a gonadotropin‐releasing hormone analogue (GnRHa). Induction of spawning was successful at the first administration of GnRHa in the 2010, 2011 and 2012 year classes. First spawning was observed at 4 or 5 days post implantation, which indicated that oogenesis and spermatogenesis progressed within 1 year of rearing in land‐based tanks. During spawning periods, the average number of fertilized eggs and the average number of hatched larvae per spawning event in the 2010, 2011 and 2012 year classes were 20,480 eggs day?1 and 177 larvae day?1, 39,423 eggs day?1 and 9347 larvae day?1, and 819,555 eggs day?1 and 674,445 larvae day?1 respectively. Therefore, it was concluded that both male and female ELT reared in land‐based tanks were capable of reproduction at 1 year of age.  相似文献   
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The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer.  相似文献   
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Tumor cell invasion into the surrounding nervous tissue is one of the histologic hallmarks of anaplastic meningiomas. To identify other possible markers for aggression in canine meningiomas, the relationship between histologic features and the expression of molecules involved in cell adhesion, cell proliferation, and invasion was examined. Immunohistochemistry for epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), β-catenin, doublecortin (DCX), and Ki-67 was performed for 55 cases of canine meningioma. DCX was preferentially expressed in tumor cells invading the brain parenchyma (12 of 14 cases), suggesting its involvement in the invasion process. Regardless of the histologic type, E-cadherin and N-cadherin expression was observed in 31 of 55 and 44 of 55 cases, respectively. There was a significant positive correlation between DCX and N-cadherin expression and a significant negative correlation between E-cadherin and N-cadherin expression, suggesting that decreased E-cadherin and increased N-cadherin expression induce DCX expression. Typical membranous β-catenin expression was observed in 10 of 55 cases, whereas nuclear translocation was observed in 33 cases. Nuclear β-catenin expression was frequently found in anaplastic meningiomas (12 of 14 cases). The Ki-67 labeling indices were significantly higher in anaplastic meningiomas than in other types. These findings indicate that the expression of N-cadherin and DCX and the nuclear translocation of β-catenin are closely associated with the presence of invasion and anaplasia in canine meningiomas. Notably, granular cell meningiomas were negative for almost all the molecules examined, suggesting that they have a different tumor biology than other meningiomas.  相似文献   
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The present study was conducted to examine whether colostrum supplementation in peripartum goats increases the antimicrobial peptides in their milk. Goats were orally administered 2 ml of colostrum whey products (colostrum group) or water (control group) daily, from 2 weeks before until 2 weeks after kidding. Body weights of mothers and kids were measured. Blood, milk, and fecal samples were collected from the mothers, and blood samples were collected from the kids. Concentrations of milk antimicrobial peptides (beta‐defensin, cathelicidin, lactoferrin, S100A7, lactoperoxidase, and immunoglobulin A [IgA]) were determined. IgA and nutritional parameters (glucose, total cholesterol, triglyceride, ketone bodies, and non‐esterified fatty acids) were also determined in the blood of mothers and kids. Milk IgA and lactoferrin concentrations were higher in the colostrum group than in the control group. Conversely, lower milk concentrations of S100A7 were observed in the colostrum group than that in the control group. Plasma IgA concentrations were higher for kids from the colostrum group than for those from the control group. These results suggest that oral administration of colostrum in pregnant goats increases IgA concentration in postpartum milk, which can subsequently improve the health of their kids.  相似文献   
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Pneumocystis carinii pneumonia was diagnosed by postmortem examination of a one-year-old Cavalier King Charles Spaniel with four-week history of dyspnea. Cytologic and histologic examination of lung tissues revealed numerous P. carinii trophozoites and cysts, and P. carinii specific DNA was detected by polymerase chain reaction. The dog showed hypogammagloblinemia and extremely low levels of serum IgG. It was considered that P. carinii pneumonia in this case was associated with an immunodeficient condition which has already been reported in Miniature Dachshunds.  相似文献   
68.
Natural rubber is a critical agricultural material, and guayule (Parthenium argentatum Gray) is the most promising domestic, agricultural source. A study on guayule was initiated to provide information on the water requirements and plant water stress behavior for this new perennial crop. Measured evapotranspiration averaged 3000, 2410, 2040, 1720, 1470 and 1520 mm, from May 1981 to December 1982, in decreasing order of water applications on the six irrigation treatments from the wettest to the driest. These evapotranspiration values indicated that the water use by guayule can be higher than many former estimates for an arid-type crop. Plant canopy temperatures also showed a progressive increase in plant water stress as irrigation water amounts decreased. The two-fold decrease in evapotranspiration from the wet to dry treatments corresponded to a four-fold increase in plant water stress indices based on remote infrared thermometer measurements. Both the concepts of stress degree days and crop water stress index, evaluated over the entire growing cycle, correlated well with the measured evapotranspiration. Even though the guayule plant can withstand long periods of drought, moisture stress will occur within a relatively short period of time after an irrigation for the guayule crop.  相似文献   
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Intraoperative spinal ultrasonography was performed in cervical and lumbar spine of 2 and 5 normal dogs, respectively, following ventral slot technique or dorsal or hemilamenectomy. The dura was hyperechoic, while the parenchyma was hypoechoic. The subarachnoid space was anechoic. An echogenic line was present in the center of the spinal cord, as seen in human. Pulsation of the spinal cord was noted during M-mode imaging. Clinical findings of one dog with thoracolumbar disk herniation and one with thoracic vertebral fracture/subluxation confirmed the usefulness of intraoperative spinal ultrasonography for real time evaluation of spinal canal spatial abnormalities (mass lesion and degree of spinal cord compression on scanning planes) and spinal cord motion. Follow-up ultrasound examinations were possible from 6 days postoperatively.  相似文献   
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