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141.
为了预测景泰绿洲春小麦(Triticum aestivum)、燕麦(Avena sativa)、黑麦(Secale cereale)的产草量和营养品质,通过田间试验,测得牧产草量、株高和分蘖,室内测定粗蛋白、粗脂肪、中性洗涤纤维、酸性洗涤纤维、粗灰分和可溶性碳水化合物,分析各指标之间的相关性。结果表明,收获干草的3种小谷物分蘖和株高均与可溶性碳水化合物之外其它5个营养指标存在显著相关性(P0.05),模拟轮牧的春小麦和黑麦株高与营养指标均无相关性(P0.05),燕麦和黑麦的分蘖与6个营养指标均呈显著相关(P0.05)。建立了根据株高预测产草量和营养品质的模型、用分蘖预测牧草营养品质的模型、用产草量预测牧草营养品质的模型、用分蘖和产草量两个因子综合预测营养品质的模型。经过与实测值对比,各预测模型的准确性均较高。 相似文献
142.
柳蛎盾蚧危害与丁香防御蛋白活力的关系 总被引:1,自引:0,他引:1
在柳蛎盾蚧的未危害期(5月末)、危害盛期(6月末)、危害弱期(7月末)、危害末期(8月末),测定高抗类[什锦丁香等7种(品种)]、中抗类[西南丁香等3种(品种)]、易感类[紫丁香等2种]、高感类(红丁香)13种(品种)丁香叶中的POD,SOD,CAT,PPO,PAL,TI和CI 7种防御蛋白的活性.结果表明:危害时期,丁香种(品种)对丁香防御蛋白活力有极显著影响(P<0.01).POD活性,在危害盛期,在高抗、中抗类丁香中均显著升高(P<0.05),而在易感、高感类中应激滞后,即分别在危害弱期和危害末期升高.CAT在易感类和高感类丁香防御上起主导作用,其活性在危害盛期显著升高,而中抗和高抗类未见明显变化.SOD活性,在危害盛期高抗类丁香中无显著变化,而其余3类则显著降低.PPO活性在未危害期的高低与抗性相关,在虫害盛期诱导表达的强弱也与抗性相关;PAL活性未能反映抗性品种间的差异.TI和CI活性,在未危害期的高低与其抗虫性无明显相关性,在危害盛期的升高幅度与抗虫性呈正相关.综上所述,PPO在未危害期的活力可作为筛选丁香抗虫种(品种)的指标,危害盛期POD,PPO,TI和CI活性升高的幅度与丁香抗虫性呈正相关. 相似文献
143.
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145.
Fenway Chang Andrew K.J. Linklater 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):586
A 2-year-old neutered male 35-kg golden retriever mixed breed dog was presented because of a 3-day history of increased respiratory effort. The patient was subsequently diagnosed with a lung lobe torsion and underwent lung lobectomy. Chylothorax developed after surgery and persisted for 3.5 y. Pleural access port (PAP) placement was used for long-term medical management. Several complications were encountered, including 2 episodes of PAP occlusion that were successfully treated with unfractionated heparin. The dog had a surgical site seroma and 2 episodes of pleuritis; euthanasia was elected after the second episode.Key clinical message:This case demonstrates successful long-term management of chylothorax with a pleural access port and management of 3 complications. Instead of the less accessible and more expensive tissue plasminogen activator, unfractionated heparin was used as an effective treatment for PAP occlusions. 相似文献
146.
Dong Ruan Qiuli Fan Ahmed Mohamed Fouad Yunyun Sun Shengshu Huang Aiji Wu Chuxiao Lin Zhixiang Kuang Chang Zhang Shouqun Jiang 《Journal of animal science》2021,99(2)
Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition. 相似文献
147.
Taesik Yun Yoonhoi Koo Sanggu Kim Wonguk Lee Hakhyun Kim Dongwoo Chang Soochong Kim Mhan-Pyo Yang Byeong-Teck Kang 《The Veterinary quarterly》2021,41(1):163
An 8-year-old neutered male Yorkshire Terrier dog presented with head pressing, vestibular ataxia, neck tenderness, and no oculocephalic reflex. A demarcated lesion in the pons was identified on MRI. The patient was tentatively diagnosed with a glioma and was treated with hydroxyurea plus imatinib and prednisolone. After 30 days of therapeutic treatment, the patient showed a clear improvement in neurological signs, which lasted for 1117 days. On day 569 after the initiation of treatment, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) was performed with no significant findings on visual analysis. The average and maximal standardized uptake values (SUVs) were 1.92 and 2.29, respectively. The tumor-to-normal-tissue (T/N) ratio was 0.97. The first evidence of clinical deterioration was noticed on day 1147. On day 1155, 3,4-dihydroxy-6-[18F]-fluoro-l-phenylalanine (18F-FDOPA)-PET was performed. High uptake of 18F-FDOPA was observed in the intracranial lesion. The mean and maximal SUVs of the tumor were 1.59 and 2.29, respectively. The T/N ratio was 2.22. The patient was euthanized on day 1155 and histopathologic evaluations confirmed glioma (astrocytoma). This case shows that chemotherapy with hydroxyurea plus imatinib may be considered in the treatment of canine glioma. Furthermore, this is the first case describing the application of 18F-FDG and 18F-FDOPA in a dog with glioma. 相似文献
148.
鸭甲型肝炎(duck hepatitis A,DHA)是危害养鸭业的主要疾病之一,是一种雏鸭的急性、高度致死性传染病。本研究旨在研制一种对我国流行的鸭甲型肝炎血清1型(DHAV-1)和血清3型(DHAV-3)病毒具有交叉中和作用的单克隆抗体(monoclonal antibody,McAb)。人工合成12条DHAV-1和DHAV-3的VP1蛋白共有的抗原表位肽,分别与钥孔血蓝蛋白(keyhole limpet hemocyanin,KLH)载体偶联作为免疫抗原,免疫BALB/c小鼠制备McAb。通过检测McAb与DHAV-1和DHAV-3的交叉反应性,测定McAb对病毒增殖的抑制效率、中和效价以及攻毒保护率等来筛选McAb。本研究共获得了12株稳定分泌McAb的杂交瘤细胞株,其中6株(C1、C4、C7、C12、C13、C16)分泌的McAb同时与DHAV-1和DHAV-3发生特异性交叉反应; C1、C4、C7、C16可以抑制DHAV-1和DHAV-3在鸭胚中的增殖,抑制率在75.34%~100.00%不等;对DHAV-1和DHAV-3的中和效价:C1(1:3&1:5)、C4(1:3&1:3)、C7(1:10&1:11)和C16(1:9&1:9);C7和C16对DHAV-1和DHAV-3攻毒雏鸭的保护率较高,分别为“70%、80%”和“100%、60%”。本研究成功研制出对DHAV-1和DHAV-3具有交叉中和活性的McAb 4株,其中2株对病毒的感染具有良好的预防效果,为DHA的防控提供了新材料和新思路。 相似文献
149.
旨在研究猪C1QTNF3基因可变剪接体的特性及miR-101通过C1QTNF3基因促进猪脂肪SV细胞成脂分化的机制。本研究采集3头30日龄健康马身猪仔公猪心、肝、脾、肺、肾、胃、股二头肌、腰大肌、皮下脂肪和背部脂肪组织样品,首先利用RT-PCR技术和生物信息学方法对C1QTNF3基因的不同转录本进行扩增和生物学特性分析,采用qRT-PCR技术检测C1QTNF3基因不同转录本在猪组织中的表达变化。随后,利用生物信息学预测发现,C1QTNF3上游的调控因子是miR-101,采用双荧光素酶报告试验验证miR-101对C1QTNF3的调控作用。最后,利用油红O染色和qRT-PCR技术检测过表达miR-101对猪脂肪SV细胞成脂分化的影响。基因克隆得到猪C1QTNF3存在两个转录本C1QTNF3和C1QTNF3-1,其中C1QTNF3-1为新鉴定的转录本;测序分析显示,与C1QTNF3相比,C1QTNF3-1的第1外显子区域缺失了219个碱基,少编码73个氨基酸。进化树分析显示,猪C1QTNF3和C1QTNF3-1蛋白序列与人和马来亚穿山甲等物种的亲缘关系较近。C1QTNF3和C1QTNF3-1在猪各组织中均有表达,且在各组织中C1QTNF3-1的表达量均极显著高于C1QTNF3(P<0.01)。过表达miR-101极显著下调C1QTNF3 3'UTR区域的荧光素酶活性(P<0.01)和C1QTNF3 mRNA的表达(P<0.01),同时增加了脂肪细胞成脂分化关键基因PPARγ、C/EBPβ、SREBP-1c和FABP4的mRNA表达量(P<0.01)。本试验成功克隆了猪C1QTNF3基因的两个可变剪接体,其中C1QTNF3-1在猪不同组织中均高表达,推测该转录本为基因发挥功能的主要亚型。并深入研究了C1QTNF3基因的上游调控因子,揭示了miR-101靶向C1QTNF3促进成脂分化的机制,丰富了C1QTNF3的生物学作用和调控网络。 相似文献
150.