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81.
The objective of this study was to examine the effects of canthaxanthin (Cx) treatment during in vitro maturation (IVM) of porcine oocytes on embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT), on intracellular glutathione (GSH) and reactive oxygen species (ROS) levels in mature oocytes, and on gene expression in both PA‐ and SCNT‐derived blastocysts. To determine the optimal effective concentration of Cx, porcine oocytes were cultured in IVM medium supplemented with various concentrations (0, 20, 40 and 80 μM) of Cx for 22 hr. Compared to other groups, supplementation with 40 μM Cx significantly improved blastocyst formation rates after PA (< .05), but no significant differences were observed among groups in total blastocyst cell numbers. Subsequently, oocytes were cultured in IVM medium supplemented with or without 40 μM Cx. Oocytes treated with 40 μM Cx showed significantly increased cleavage and blastocyst formation rates after SCNT compared to the control group (< .05). Moreover, significantly increased intracellular GSH and reduced ROS levels were observed in the Cx‐treated group (< .05). In addition, both PA‐ and SCNT‐derived blastocysts from the 40 μM Cx‐treated group showed significantly increased mRNA expression of Bcl2 and Oct4 and decreased Caspase3 expression level (< .05), when compared with the control group. PA‐derived blastocysts from the 40 μM Cx‐treated group also exhibited significantly decreased expression of Bax (< .05). Our results demonstrated that treatment with 40 μM Cx during IVM improves the developmental competence of PA and SCNT embryos. Improvement of embryo development by Cx is most likely due to increased intracellular GSH synthesis, which reduces ROS levels in oocytes, and it may also positively regulate apoptosis‐ and development‐related genes.  相似文献   
82.
本研究以半血野生盘羊和欧拉羊杂交F1代羊,即含1/4野生盘羊血统羊为素材,对含1/4野生盘羊血统羊生长发育规律进行了分析。结果表明:含1/4野生盘羊血统羊早期生长发育快,体重与体尺间呈极显著的正相关(P0.01),体尺与体重的最优回归方程Y=-37.758+0.431X3+0.529X1,R2=0.962。  相似文献   
83.

Aim

A prospective, observational study to determine the prevalence of post‐exercise conditions at Australian Greyhound race meetings and to assess association with race performance and other environmental, race‐ and dog‐related factors was undertaken.

Methods

A total of 4020 starters were observed (2813 Greyhounds, 1009 trainers, 536 races, 52 race meets, 48 race dates and 11 race tracks) following a race. The presence of diaphragmatic flutter (DF), ataxia, seizure, collapse or sudden death was recorded. Risk factors were screened by univariable logistic regression prior to multivariable backward stepwise model building.

Results

In this study, 962 starters (n = 768 dogs) had DF (23.9%), 16 starters were ataxic (0.4%) and there were no observed cases of collapse, seizure or sudden death. Race track location, increasing race distance, race grade based on increasing 1st place prize value, lower (earlier) race number at the meeting, age, a previous observation of DF at the last start, females, colour (white) and better finishing position were all associated with an increased risk of a Greyhound being observed with DF. However, when logistic regression assessing the random effect of dog was performed, the presence of previous DF was not significant. In this cohort, DF was common following strenuous exercise in Greyhounds and on its own does not appear to result in reduced performance or distress to the animal.

Conclusion

The incidence of ataxia was low and collapse, seizure and sudden death were not observed. However, even though uncommon, ataxia has welfare concerns for racing Greyhounds that warrants further investigation.  相似文献   
84.
本文具体介绍了一个农牧民家庭档案管理软件系统,该系统采用数据分散收集、查询与统一集成处理相结合的两级数据库设计结构,既能适应目前基层乡镇独立建立农牧户家庭档案的发展现状,也为进一步向网络化管理平滑过渡建立了统一规范的数据基础.系统实现中针对家庭档案的特点解决了录入数据格式、录入项目灵活设置等问题,满足了家庭档案格式、主题随时间不断扩展、变化的需求.还实现了统计结果查询、多维度统计分析等数据分析的特色功能来为管理决策分析服务.这些功能为建立统一规范、可扩展的实用农牧民家庭档案提供了保障.使该系统成为具体落实农牧户家庭档案工作的一种有效实践手段.  相似文献   
85.
A foal was examined for abnormal upper airway noise. Endoscopically, there were narrowed nasal passages and an extralumenal mass of the cranial trachea. Using ultrasonography and magnetic resonance (MR) imaging of the larynx and cranial cervical trachea, irregular margins of the laryngeal cartilages and first tracheal ring containing areas consistent with fluid were identified. In MR images, a widened nasal septum was seen that contained material consistent with fluid. Postmortem examination confirmed the diagnosis of nasal septal, laryngeal, and cranial cervical tracheal cyst‐like lesions. This is a unique congenital condition, in which premortem imaging was instrumental in defining the abnormalities.  相似文献   
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以3头安装永久性瘤胃瘘管的泌乳前期荷斯坦奶牛为试验动物,在精粗比为55:45的日粮条件下,采用In sacco法测定了不同温度和时间烘烤加工处理的玉米在奶牛瘤胃内干物质和淀粉的降解规律。结果表明,玉米经过不同温度和时间的烘烤处理,干物质和淀粉的瘤胃降解率都有不同程度的降低,随着温度逐渐升高、作用时间逐渐延长,干物质和淀粉的降解率也逐渐降低。在所有处理组中,140℃35min处理组可以明显降低玉米的瘤胃淀粉降解率(P〈O.05),比未处理玉米组降低了15.26%。淀粉在瘤胃中降解的影响因素最主要的是淀粉的快速可溶部分和降解速率。  相似文献   
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