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91.
92.
选取28日龄断奶的三元[杜×(大×长)]杂交仔猪96头,平均体重为(7.46±0.38)kg,按体重和 性别随机分为4个处理组,每个处理组3个重复,每个重复8头仔猪,公母各半。第1个处理组为空白 组,第2、3、4个处理组在相同的基础日粮中分别添加0.1%、0.2%和0.4%的甘露寡糖,研究甘露寡糖对断 奶仔猪肠道菌群的影响。结果表明:1、各实验组肠道大肠杆菌的浓度极显著低于对照组。2、第3组和 第4组其结肠、盲肠和直肠中双歧杆菌增殖显著。第2组中只有结肠中双歧杆菌显著高于对照组,但盲 肠和直肠中双歧杆菌增殖不明显。3、各个处理组肠道中乳酸杆菌的浓度与对照组相比差异不显著。 相似文献
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以燕麦耐盐碱性品种白燕二号和盐碱敏感性品种草莜一号为试验材料,采用中性盐NaCl、Na2SO4及碱性盐Na2CO3、NaHCO3按摩尔比1∶1混合,研究不同盐、碱胁迫对燕麦生物产量及吸收Na+、K+的影响。结果表明,随着盐、碱胁迫浓度的增加,2个品种根、茎、叶中Na+含量增加,K+含量减少,K+/Na+和生物量下降,盐胁迫下K+/Na+及生物量降幅小于碱胁迫,Na+含量增幅小于碱胁迫;且同浓度胁迫下,盐胁迫较碱胁迫叶片中Na+含量较低,K+含量、K+/Na+较高。2个品种间存在差异,盐、碱胁迫下白燕二号中增加的Na+含量小于草莜一号,减少的K+含量、K+/Na+及生物量小于草莜一号,尤其在高盐、碱胁迫下叶片中K+含量及K+/Na+远大于同浓度下的草莜一号;白燕二号比草莜一号根中截留Na+和地上部选择性吸收K+能力强。 相似文献
95.
Cultivation of fungi for food by fungus-growing ants (Attini: Formicidae) originated about 50 million years ago. The subsequent evolutionary history of this agricultural symbiosis was inferred from phylogenetic and population-genetic patterns of 553 cultivars isolated from gardens of "primitive" fungus-growing ants. These patterns indicate that fungus-growing ants succeeded at domesticating multiple cultivars, that the ants are capable of switching to novel cultivars, that single ant species farm a diversity of cultivars, and that cultivars are shared occasionally between distantly related ant species, probably by lateral transfer between ant colonies. 相似文献
96.
TH Morris SW Paine PW Zahra EC Li SA Colgan SL Karamatic 《Australian veterinary journal》2020,98(12):578-585
Animals used in sport should be treated as required to ensure animal welfare but any such use of medication should also be controlled to ensure integrity. Pharmacokinetic studies on groups of six greyhounds were performed to measure plasma and urine levels of carprofen and firocoxib to inform medication control advice. Using the standard methodology for medication control the Irrelevant Plasma Concentration was determined as 20 and 2 ng/mL for carprofen and firocoxib, respectively. The Irrelevant Urine Concentration was also determined as 0.3 and 2 ng/mL for carprofen and firocoxib, respectively. These Irrelevant Plasma and Urine Concentrations will allow laboratory Screening Limits, Detection Times and Withdrawal Time advice to be determined and publicised by regulators of greyhound racing. The Screening Limits will also inform Recommended Limits of Detection if meat-containing residues of these medications are fed to greyhounds. 相似文献
97.
目的 探究广州动物园一例死亡白狐Alopex lagopus肾脏中鉴定出的星状病毒的遗传变异情况。方法 对死亡白狐进行剖检,利用半巢式RT-PCR对内脏器官进行病原学检测,对扩增出的病毒株的RdRp基因序列进行相似性分析。结果 死亡白狐的肾脏苍白肿大,被膜难以剥离,肾脏中检测出的星状病毒RdRp基因呈阳性。RdRp基因与9株参考毒株的核苷酸相似性为67.5%~96.2%,其中与香港猫源星状病毒1637F的核苷酸相似性(96.2%)最高。结论 本研究为星状病毒在野生哺乳动物间的跨种传播及肠外器官中的感染提供了依据。 相似文献
98.
【目的】研究蓝刺头花絮水提物的降血糖作用。【方法】采用煎煮法制备蓝刺头花絮水提物。使用四氧嘧啶诱导糖尿病小鼠模型,并随机分为4组,每组10只,蓝刺头高、中、低剂量组小鼠每天分别灌胃1.00,0.50和0.25g/mL的蓝刺头花絮水提物,对照组灌等量蒸馏水,于试验0,7,14和21d测定糖尿病小鼠空腹血糖、体质量;21d测定小鼠口服糖耐量、肝糖原、血清胰岛素、胰高血糖素及肾上腺素的含量。【结果】蓝刺头花絮水提物能够显著降低糖尿病小鼠的空腹血糖,改善糖尿病小鼠的口服糖耐量,升高肝糖原及血清胰岛素水平,极显著降低血清肾上腺素含量,对体质量和血清胰高血糖素含量无显著影响。【结论】蓝刺头花絮水提物能够降低糖尿病小鼠的血糖水平,且呈剂量依赖关系。 相似文献
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100.
Hydromorphone (H) may be an effective analgesic agent in cats, but fear of negative behavioral side‐effects associated with opioids is cited as a reason for avoiding this class of analgesics in cats. This study was designed to assess onset and duration of antinociception using an established feline thermal threshold model in cats, given an accepted clinical dose of 0.1 mg kg?1 of H. In addition, cats were observed for changes in behavior and other side‐effects. Six adult cats from an established colony (four spayed females and two castrated males, 4.7–7.0 kg) received 0.1 mg kg?1 H IV following establishment of baseline thermal threshold (TT) values. TT was tested at 15 minutes post‐injection, then at every 30–60 minutes for 12 hours. Side‐effects and behavior changes were recorded for 12 hours. Changes in TT over time were analyzed using a one‐way anova ; a p‐value <0.05 was considered significant. TT increased from a pre‐treatment value of (mean ± SD) 40.9 ± 1.65 °C to instrument cutout (55.5 °C) within 30 minutes for 5/6 cats. Mean TT was significantly elevated above baseline from 15 to 450 minutes after treatment. There was a significant increase in skin temperature from 15 to 300 minutes with peak increase of 1.55 °C at 135 minutes. Side‐effects included mydriasis (6/6) and nausea (4/6), characterized by licking, foaming, and gagging. Mydriasis occurred within 10–30 seconds of injection and persisted for 5–7 hours. Nausea was noted within 2 minutes of injection and persisted for 30–90 minutes; no vomiting occurred. Commonly observed behavioral changes included ventral tail curl (6/6 cats, onset 5–45 minutes, duration 4–5 hours) and euphoria (5/6 cats, onset <6 minutes for 4/6, duration 1–6 hours). 2/6 cats were profoundly sedate. Three cats showed signs of dysphoria with or without increased motor activity with variable onset and duration. Dysphoric behavior included staring, pacing, vocalizing, and sudden movements. 3/6 cats exhibited both euphoria and dysphoria at different times during the study. At no time were cats difficult to restrain or work with. Return to baseline behavior occurred 7–8.5 hours post‐injection. Mydriasis did not correlate closely with antinociception. Signs of sedation and euphoria corresponded with onset of antinociception, but not duration. Tail curl signs correlated with antinociception. In this model, H proved to be a rapid acting, potent, analgesic with a long (7.5 hours) duration of action. The most common behavioral changes noted were ventral tail curl, euphoria, and sedation. Mydriasis and nausea were noted as side‐effects. 相似文献