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21.
The aim of this study was to determine whether vitrification is an effective method when used for Japanese Black Cattle (Wagyu) in vivo‐derived embryos, collected following a superovulation treatment and embryo transfer (MOET) programme. In vivo‐derived morula and blastocysts collected on day 7 after artificial insemination, were vitrified using a modified droplet vitrification (MDV) procedure and subsequently warmed for transfer (ET) into synchronized recipients. Fresh embryos, and embryos cryopreserved using a standardized slow freezing procedure (direct thaw/direct transfer, DT) served as ET controls. Two different follicle‐stimulating hormone (FSH) sources, Folltropin® Canada (FSH BAH, 24 donors) and a brand prepared by the Chinese Academy of Science (FSH CAS, 16 donors), were compared in a series of superovulation outcomes following well‐established FSH administration protocols. Following data analysis, the total number of ovulations recorded at the time of embryo flushing (10.5 vs 8.5; p = 0.28) and the total number of transferable embryos (6.2 vs 5.1; p = 0.52) were similar between the two FSH sources. ET for MDV (39.7%, n = 78), DT (35.2%, n = 71) and fresh controls (47.1%, n = 34) resulted in similar pregnancy rates (p > 0.05). When MDV was used, a higher pregnancy rate (42.6%) resulted from the transfer of vitrified morulae, when compared to the DT counterparts (24.3%), (p = 0.05). Transfer of vitrified morulae resulted also in higher pregnancy rate, when compared to the transfer of vitrified blastocysts (42.6% vs. 29.4%; p < 0.05). Transfer of DT blastocysts resulted in higher pregnancy rate than morulae, similarly cryopreserved (47.1% vs. 24.3%, p < 0.05). In conclusion, MDV is an effective alternative methodology for cryopreservation of in vivo‐derived embryos. This study gives also indication that, compared to vitrified blastocysts, MDV of morula stage embryos results in higher pregnancy rates following warming and transfer into synchronized recipients.  相似文献   
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Radioactive iodine (131I) was used in the treatment of a 12-year-old female dog with hyperthyroidism resulting from a large, unresectable (and metastatic) thyroid carcinoma associated with signs of severe inspiratory stridor and dyspnea. Hyperthyroidism was diagnosed on the basis of clinical signs (polyuria, polydipsia, polyphagia, weight loss, nervousness) and high basal serum thyroxine (T4) concentrations, as well as thyroid radioiodine kinetic studies that showed a high radioiodine uptake into the thyroid (% thyroid uptake) and markedly increased serum concentrations of protein-bound iodine-131 (PB131I) after 131I tracer injection. Thyroid imaging revealed diffuse radionuclide accumulation by the tumor, which involved both thyroid lobes. The dog was treated with three large doses of radioiodine (131I), ranging from 60 to 75 mCi, given at intervals of 5 to 7 months. The dog became euthyroid, and the size of the tumor decreased by approximately 25% after each 131I treatment, improving the severe inspiratory stridor and dyspnea, but both the hyperthyroid state and breathing difficulty recurred within a few months of each treatment. The dog was euthanatized 5 months after the last treatment because of progressive tracheal compression and pulmonary metastasis.  相似文献   
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Swine uterine capacity affects litter size, and it could be used as a selection parameter of reproductive performance. Although there are some controversial results, evidences show that the catheter penetration length is positively correlated with litter size, and it could be used as a tool for predicting selection methods. The aim of this study was to determine whether there is any association between the prenatal survival rate and placental size at 70 days of gestation, the vaginal length [catheter penetration length during artificial insemination (AI)] and the uterine capacity in a homogeneous group of gilts. Sixty-six commercial-line gilts in pre-pubertal phase had their oestrus induced by hormonal treatment [600 UI of Equine Chorionic Gonadtrophin (eCG) i.m. and after a 72-h period 5 mg of luteinizing hormone (LH) i.m.], but only 40 gilts showed cyclicity after induction. The AI catheter penetration length was tested on these 40 gilts at the moment of AI using a calibrated AI catheter. Four gilts returned to oestrus and the other 36 were killed at around day 69 of pregnancy. The uterine length and weight showed a significant and positive correlation with the prenatal survival rate (p <0.05). The catheter penetration length was unable to predict the conceptus survival rate on 70 days of gestation; however, the uterine size influenced the survival rate positively. The mean placental area was positively correlated with the mean placental weight (p <0.0001), and both with the mean foetal weight (p <0.0001 and p <0.001, respectively). The analysis of the results obtained showed that neither did the catheter penetration length measurement during AI, nor the prenatal survival rate on day 70 of pregnancy predict the uterine capacity, but the uterine and placental size had a significant influence on the prenatal survival and foetus weight, respectively.  相似文献   
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Results of long-term treatment were evaluated in 200 dogs with primary hypoadrenocorticism and 5 dogs with spontaneous secondary hypoadrenocorticism. Fludrocortisone acetate initially was used for mineralocorticoid replacement in 190 of the dogs with primary hypoadrenocorticism. The daily dose of fludrocortisone required in these dogs increased significantly during the treatment period (median, 2.6 years) from an initial median dose of 13.1 μg/kg to a final dose of 22.6 μg/kg. In 27 of the 200 dogs, mineralocorticoid therapy was changed from fludrocortisone to desoxycorticosterone pivalate (DOCP) because of adverse effects, poor response, or financial considerations. The dose of DOCP required in the 33 dogs (27 dogs plus 6 dogs initially given DOCP) increased significantly during the treatment period (median, 3.5 years) from an initial median dose of 1.56 mg/kg to a final dose of 1.69 mg/kg; the interval between DOCP injections ranged from 14 to 35 days (median, 30 days). The dose of prednisone administered to the dogs with primary hypoadrenocorticism decreased significantly from an initial median dose of 0.3 mg/kg to a final dose of 0.2 mg/kg; the drug was discontinued in 22 dogs due to adverse effects. The 5 dogs with secondary hypoadrenocorticism received only glucocorticoid replacement therapy (prednisone) at initial and final daily dosages of 0.41 mg/kg and 0.25 mg/kg, respectively, during a median treatment period of 4.4 years. More than 80% of the dogs were considered to have a good to excellent response to therapy. The median survival time of all 205 dogs was 4.7 years. There were no differences in response to treatment or survival between dogs treated with fludrocortisone and those receiving DOCP, or between dogs with primary hypoadrenocorticism and those with secondary hypoadrenocorticism.  相似文献   
27.
多效唑调节杂交水稻制种父本花期利弊探讨   总被引:1,自引:0,他引:1  
目前在杂交水稻制种生产上,应用 15%多效唑调节发育偏快的父本较为普遍.但因施用技术不当,效果差异很大,甚至导致制种减产或失收.分析、探讨了其使用的利弊.  相似文献   
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