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为研究长沙市生态动物园引进的非洲肯尼亚斑马蜱的线粒体DNA的部分细胞色素C氧化酶第Ⅰ亚基(cytochrome coxidase subunit l,pcox1)基因序列的遗传变异情况,本研究对其线粒体pcox1基因序列进行PCR扩增,并使用DNAStar(V5.01)、Clustalx2.0及Phylip3.67进行分析。结果显示,几种斑马蜱为消色牛蜱、丽色扇头蜱和璃眼蜱属,种间差异为0.7%~20.2%,种内相似度较高,表明pcox1基因可作为蜱种间遗传变异研究的标记,研究结果为蜱的分类鉴定以及进一步的分子流行病学调查奠定了基础。 相似文献
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Objective To determine ocular distribution and toxicity of a single injection of intravitreal triamcinolone acetonide (TA) in normal horses.
Animals studied Six adult horses, donated to North Carolina State University.
Procedures Six horses were injected intravitreally with either 10, 20, or 40 mg ( n = 2 each) of TA. The opposite eye of each horse was injected with balanced salt solution (BSS). Ocular toxicity was assessed by biomicroscopy, tonometry, indirect ophthalmoscopy, and electroretinogram. Aqueous humor (AH), vitreous humor (VH), and plasma samples were collected. Horses were euthanized 7 or 21 days after injection and eyes enucleated for histopathology. TA concentrations in AH, VH, and plasma were measured by HPLC.
Results Three control eyes and one TA eye developed inflammation after injection or collection of AH. Positive bacterial cultures ( Corynebacterium spp., Staphylococcus spp., and Streptococcus spp.) were obtained from three of these eyes. Other than transient corneal edema in TA injected eyes, which resolved by 7 days after injection, no other changes were observed. TA crystals were visible within the vitreous body. No evidence of TA toxic effect was noted on histopathology. TA was detected in all AH and VH samples from treated eyes following injection. Drug was not detected in the plasma.
Conclusions There was no evidence of overt toxicity from intravitreal TA in normal horses and a single intravitreal injection resulted in TA ocular levels for 21 days. However, the risk for bacterial infections with intravitreal injection or anterior chamber aspirations in horses is high. Use of topical and systemic antibiotics after injection is recommended. 相似文献
Animals studied Six adult horses, donated to North Carolina State University.
Procedures Six horses were injected intravitreally with either 10, 20, or 40 mg ( n = 2 each) of TA. The opposite eye of each horse was injected with balanced salt solution (BSS). Ocular toxicity was assessed by biomicroscopy, tonometry, indirect ophthalmoscopy, and electroretinogram. Aqueous humor (AH), vitreous humor (VH), and plasma samples were collected. Horses were euthanized 7 or 21 days after injection and eyes enucleated for histopathology. TA concentrations in AH, VH, and plasma were measured by HPLC.
Results Three control eyes and one TA eye developed inflammation after injection or collection of AH. Positive bacterial cultures ( Corynebacterium spp., Staphylococcus spp., and Streptococcus spp.) were obtained from three of these eyes. Other than transient corneal edema in TA injected eyes, which resolved by 7 days after injection, no other changes were observed. TA crystals were visible within the vitreous body. No evidence of TA toxic effect was noted on histopathology. TA was detected in all AH and VH samples from treated eyes following injection. Drug was not detected in the plasma.
Conclusions There was no evidence of overt toxicity from intravitreal TA in normal horses and a single intravitreal injection resulted in TA ocular levels for 21 days. However, the risk for bacterial infections with intravitreal injection or anterior chamber aspirations in horses is high. Use of topical and systemic antibiotics after injection is recommended. 相似文献
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[目的 ]构建重大动物疫病暴发流行预警指标体系。[方法 ]以禽流感和口蹄疫为例,采用文献调研法和德菲尔专家咨询法中的专家会议法初拟重大动物疫病预警体系的框架和指标;应用德菲尔专家咨询法评价预警指标的重要性、可操作性;应用组合权重法比较各指标综合影响的大小,并将指标分类。[结果 ]筛选出禽流感和口蹄疫预警预报一级指标6项(易感动物、饲养管理和免疫情况等)以及二级指标14项(免疫效果、环境消毒、温度等),并将指标分为三类(关键指标、重要指标和一般指标)。[结论 ]初步构建了重大动物疫病暴发流行预警指标体系。 相似文献
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中国荷斯坦种公牛BLAD遗传缺陷的分子检测及系谱分析 总被引:1,自引:0,他引:1
本试验运用限制性片段长度多态性聚合酶链式反应(RFLP-PCR)方法,检测我国荷斯坦种公牛白细胞粘附缺陷(bovine leukocyte adhesion deficiency,BLAD)基因的携带频率。共检测了来自全国14个公牛站的587头种公牛,发现BLAD携带者8头,携带率为1.36%。对现有公牛系谱信息分析显示,携带者公牛来自美国、加拿大和中国,其中6头携带者公牛可以追溯到共同祖先Osborndale Ivanhoe。此外,本研究还对我国荷斯坦牛遗传缺陷的控制和携带者公牛的利用提出建议。 相似文献