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91.
The aim of this study was to evaluate the effects of hCG, progesterone and oestradiol supplementation on nuclear and cytoplasmic maturation of canine oocytes cultured for 24, 48, 72 and 96 h. Oocytes obtained from 18 healthy bitches were divided into three groups according to their reproductive status (follicular, luteal and anoestrus stages) and cultured in TCM 199 + 25 UI/ml of hCG + 1 μg/ml of progesterone + 1 μg/ml of 17‐β oestradiol or without hormonal supplementation (control) for different periods. Then, they were stained with FITC‐LCA‐Hoescht for chromatin configuration and cortical granules distribution and evaluated under an epifluorescence microscope. Culture time and the influence of different stages of the oestrous cycle were also evaluated. The present study demonstrated that there was no significant difference among the reproductive stages. With regards to culture medium, only oocytes from the supplemented medium were able to complete meiosis; however, significant difference was only noticed in the percentage of MI stage oocytes (p < 0.05) in the follicular and luteal group at 72 h of culture. Most oocytes in germinal vesicle, germinal vesicle breakdown and metaphase I stage had cortical granules distributed throughout the cytoplasm (immature pattern), irrespective of the culture period (p < 0.05). Cortical granules distributed immediately beneath the plasma membrane (mature) was only observed in metaphase II stage oocytes, but not all of them presented matured cytoplasm. Our results reveal that cortical granules distribution in canine oocytes matured in vitro did not progressed in correspondence with nuclear stage changes and are in accordance with those from other species.  相似文献   
92.
This study was conducted to investigate the pattern of DNA methylation in pronuclearstage mouse embryos derived from vitrified-warmed oocytes.Mouse oocytes at metaphase Ⅱ (MⅡ) stage of meiosis were all...  相似文献   
93.
牛乳免疫球蛋白和补体含量测定   总被引:3,自引:0,他引:3  
用琼脂单项免疫扩散法测定牛乳免疫球蛋白和补体含量。结果表明:初乳免疫球蛋白和补体C3含量极显著高于常乳(P〈0.01);初乳补体C4含量显著高于常乳(P〈0.05);初乳中免疫球蛋白和补体含量于产后3天达到高峰。  相似文献   
94.
《中国动物检疫》2011年第1期,刊登了江苏省如东县动物卫生监督所高丰撰写的《我县首例动物防疫行政复议案件顺利结案》一文,本刊第4期又刊登了陕西省汉中市汉台区动物卫生监督所任润和等作者撰写的《对〈我县首例动物防疫行政复议案件顺利结案〉一文的商榷》,本作者与前两期作者在法律适用  相似文献   
95.
96.
Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation.  相似文献   
97.
试验旨在分离鉴定犬副流感病毒(canine parainfluenza virus,CPIV),并对其生物学特性进行研究。用Vero细胞接种感染CPIV阳性犬肺脏组织,盲传4代,收集72 h病毒液进行RT-PCR鉴定、电镜观察、血凝试验、热敏性试验、紫外照射试验及病毒一步生长曲线的测定,同时扩增N基因进行序列分析,并构建系统进化树。结果显示,试验成功从出现咳嗽、流鼻涕等呼吸系统疾病症状的病犬肺脏中分离出1株CPIV,命名为CPIV-BJ01;RT-PCR扩增结果发现,在534 bp处有特异性目的条带。病毒电镜观察发现,其超微结构呈圆形、有囊膜、直径在80~200 nm之间;血凝试验显示,病毒在4和37℃均能凝集1%猪红细胞,与报道的CPIV血凝特性一致;病毒对热敏感,长时间高温下病毒毒价会随之下降;紫外照射可使病毒在短时间内对细胞的感染性急剧下降。病毒一步生长曲线测定结果显示,在12~48 h病毒高速增殖,细胞培养液中病毒滴度急剧上升,之后趋于稳定。CPIV N基因序列与19株有代表性的副流感病毒N基因相比,其核苷酸序列同源性为97.1%~99.8%。遗传进化分析表明,CPIV-BJ01与PIV5 1168-1(登录号:KC237064.1)和PIV5 ZJQ 221(登录号:KX100034.1)位于同一分支上,亲缘关系较近。  相似文献   
98.
Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually‐exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations. In this study, aimed at characterizing the mutational status of SMO, BRAF, HRAS, KRAS, NRAS and FGFR2 in CAA, we used RNA sequencing, Sanger sequencing and restriction fragment length polymorphism assays to demonstrate that 94% of CAA (n = 16) harbour a somatic HRAS p.Q61R mutation. The similarities in MAPK‐activating mutational profiles between CAA and AM implicate conserved molecular mechanisms of tumorigenesis, thus, qualifying the dog as a potentially useful model of disease. Given the relevance of RAS mutations in the pathogenesis of odontogenic tumours and other types of cancer, the results of this study are of comparative, translational, and veterinary value.  相似文献   
99.
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.  相似文献   
100.
2002年1月30日广东省丝绸(集团)公司、广东省扶贫开发领导小组办公室在阳山县文化中心广场联合举办了《科技扶贫种桑养蚕新技术》下乡活动。承办这次活动的是广东省蚕业集团有限公司,同时阳山县委县政府、阳山县丝绸公司和阳山  相似文献   
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