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91.
Won-Il Jeong Sun Hee Do Da-Hee Jeong Jae-Yong Chung Hai-Jie Yang Dong-Wei Yuan Il-Hwa Hong Jin-Kyu Park Moon-Jung Goo Kyu-Shik Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(3):299-301
Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined. 相似文献
92.
在摇瓶培养条件下对分离获得的抗逆、高效新疆紫花苜蓿中华根瘤菌(Sinorhizobium sp.) XGL026菌株的发酵条件进行优化。依据单因素试验结果,采用Plackett-Burman设计对菌体生长的影响因素进行效应评价,筛选出麦芽糖浓度、酵母膏浓度及初始pH是显著影响菌株生长的主要因子。响应面法优化获得根瘤菌XGL026的最佳培养基为:麦芽糖27.20 g·L-1,酵母膏10.54 g·L-1,K2HPO40.8 g·L-1,MgSO4·7H2O 0.2 g·L-1,NaCl 0.1 g·L-1,初始pH 6.98。在转速150 r·min-1, 28℃条件下摇瓶培养24 h,活菌数可达3.47×1012 cfu·mL-1。通过3次重复的发酵试验验证,与预测值相对误差为1.17%,表明模型拟合效果良好。 相似文献
93.
影响仔猪胃肠道发育的因素 总被引:1,自引:0,他引:1
仔猪胃肠发育的情况直接影响了营养物质的消化、吸收及利用,及时找到影响其发育的因素对仔猪的营养管理是非常有意义的。目前发现的诸多因素中,生长因子及营养物质对其发育起到促进作用,而抗营养因子往往对其发育不利。本文从生长因子、营养物质到抗营养因子角度出发,分析了它们对仔猪肠道发育影响,为今后合理配制仔猪饲养阶段的日粮提供依据。 相似文献
94.
Trinexapac-ethyl、Prohexad ione-Ca在草坪化学控制中的应用研究 总被引:2,自引:0,他引:2
为探明Trinexapac-ethyl和Prohexadione-Ca用于草坪化学控制的可行性,研究了其对高羊茅(Festuca arundinacea)生长发育的影响。结果显示:使用剂量高于0.095 kg/hm2时,Trinexapac-ethyl对高羊茅具有明显的矮化作用,在0.36kg/hm2剂量下Prohexadione-Ca的抑制率可达95.2%;Trinexapac-ethyl和Prohexadione-Ca都能使植株新增鲜重显著降低,但对新增干重影响很小,Trinexapac-ethyl对植株新增干重无影响;在施用Trinexapac-ethyl的情况下,随着留茬高度的增加新增株高减少,合理留茬高度为4-6cm;Trinexapac-ethyl和Prohexadione-Ca可以有效降低株高,从而减少草坪修剪次数。 相似文献
95.
植物内整流K~+通道AKT1的研究进展 总被引:1,自引:0,他引:1
K~+是植物生长发育所必需的大量营养元素。内整流K~+通道(Arabidopsis K~+transporter 1,AKT1)属于Shaker家族,是介导K~+吸收的重要通道,为质膜的K~+感应器,参与调节细胞的生长发育、调控气孔运动及植物蒸腾作用,能够提高植株的抗旱耐盐性,因而在植物生长过程中具有重要作用。该文概述了AKT1的结构、组织表达定位和表达调控及功能等方面的研究进展,并提出采用蛋白组学、基因工程技术及RNAi手段深入研究K~+、Na~+吸收及转运的协同调控机制,提高作物对土壤中K~+的利用效率及AKT1在植物生理代谢、抗逆性中的作用。 相似文献
96.
Qiyan Xiong Yanna Wei Zhixin Feng Yuan Gan Zhanjun Liu Maojun Liu Fangfang Bai Guoqing Shao 《Veterinary journal (London, England : 1997)》2014,199(2):268-274
An attenuated Mycoplasma hyopneumoniae vaccine that requires intrathoracic administration is commercially available for use against mycoplasmal pneumonia in China. Given the limitations of such a route of administration, this study was undertaken to assess the capacity of an ISCOM-matrix adjuvant to enhance immunogenicity following intramuscular use. Immune responses in pigs following vaccination and subsequent intra-tracheal bacterial inoculation were examined using lymphocyte proliferation, serology and mucosal IgA in both nasal and saliva swabs.Vaccination induced clear lymphocyte proliferation, but only slight serum antibody responses although these were significantly increased following experimental infection. Mucosal IgA was not detected in either nasal or salivary secretions. Following bacterial challenge, animals vaccinated with the adjuvant-containing live vaccine exhibited less severe pulmonary lesions (median score 3.67) than unvaccinated pigs (median score 13.58). The degree of ciliary loss on the respiratory tract surface was reduced in vaccinated pigs compared with experimentally infected controls. The findings indicated that the adjuvant vaccine administered IM provided protection against experimentally induced mycoplasmal pneumonia and could have commercial potential. 相似文献
97.
98.
通过对鸭静脉接种或眼-鼻-口腔-泄殖腔接种禽流感病毒A/duck/Guangdong/220/2004(H5N1)后,采用免疫组织化学方法检查病毒核蛋白抗原,探讨了该病毒在组织器官中的定位与分布.结果表明,病毒核蛋白抗原主要存在于鸭的心肌细胞、肝细胞、枯否氏细胞、胰腺泡上皮细胞、肾小管上皮细胞、血管内皮细胞和血液吞噬性自细胞;在气管和支气管黏膜上皮,脑组织,肠黏膜上皮,胸腺、法氏囊、脾脏和肺脏的巨噬细胞或组织细胞以及坏死的细胞碎片中也可检查到少量病毒核蛋白抗原;而在食管、胃、睾丸、卵巢、甲状腺、肾上腺、哈德氏腺、骨骼肌等未检查到该抗原. 相似文献
99.
Multi‐level mixed models for evaluating factors affecting the mortality and weaning weight of piglets in large‐scale commercial farms in central China 下载免费PDF全文
This study investigated the factors affecting piglet mortality (square root of mortality, SQRM) and average weaning weight (AWW) in commercial farms in central China. Information on sow diets, management and climate from 2478 weaning batches completed in 16 pig farms was collected from 2009 to 2013. Multi‐level mixed models, which included batch level (level 1) and farm level (level 2), were used to analyze the factors associated with SQRM and AWW. The mean values of SQRM and AWW were 2.52% (SD = 0.96) and 7.31 (SD = 0.77), respectively. Lactation sow diets supplemented with oregano essential oils (OEOs) decreased the SQRM (P < 0.05) and increased the AWW of piglets (P < 0.01). The SQRM was lower in period 2 (June to September, hot) than in period 1 (February to May, warm) and period 3 (October to January, cold; P < 0.05 and 0.001, respectively). The AWW was lower in periods 2 and 3 than in period 1 (P < 0.01). In conclusion, supplying OEOs to lactation diets can increase the weaning weight and reduce the mortality of piglets. The sources of variations in SQRM and AWW are of greater concern in the warm season than in the hot season. 相似文献
100.
Qian ZHANG Mo LI Yuan YIN Shiyong GE Danjie LI Ibrahim M. AHMAD Ghulam NABI Yanfeng SUN Xu LUO Dongming LI 《Integrative zoology》2023,18(5):891-905
Human commensal species take advantage of anthropogenic conditions that are less likely to be challenged by the selective pressures of natural environments. Their morphological and physiological phenotypes can therefore dissociate from habitat characteristics. Understanding how these species adjust their morphological and physiological traits across latitudinal gradients is fundamental to uncovering the eco-physiological strategies underlying coping mechanisms. Here, we studied morphological traits in breeding Eurasian tree sparrows (ETSs; Passer montanus) among low-latitude (Yunnan and Hunan) and middle-latitude (Hebei) localities in China. We then compared body mass; lengths of bill, tarsometatarsus, wing, total body, and tail feather; and baseline and capture stress-induced levels of plasma corticosterone (CORT) and the metabolites including glucose (Glu), total triglyceride (TG), free fatty acid (FFA), total protein, and uric acid (UA). None of the measured morphological parameters varied with latitude except in the Hunan population, which demonstrated longer bills than those in other populations. Stress-induced CORT levels significantly exceeded baseline levels and decreased with increasing latitude, but total integrated CORT levels did not vary with latitude. Capture stress-induced significantly increased Glu levels and decreased TG levels, independent of site. However, the Hunan population had significantly higher baseline CORT, baseline and stress-induced FFA levels, but lower UA levels, which differed from other populations. Our results suggest that rather than morphological adjustments, physiological adjustments are mainly involved in coping mechanisms for middle-latitude adaptation in ETSs. It is worth investigating whether other avian species also exhibit such dissociation from external morphological designs while depending on physiological adjustments. 相似文献