Environmental enrichment promotes neural plasticity and cognitive ability in fish

Different kinds of experience during early life can play a significant role in the development of an animal''s behavioural phenotype. In natural contexts, this influences behaviours from anti-predator responses to navigation abilities. By contrast, for animals reared in captive environments, the homogeneous nature of their experience tends to reduce behavioural flexibility. Studies with cage-reared rodents indicate that captivity often compromises neural development and neural plasticity. Such neural and behavioural deficits can be problematic if captive-bred animals are being reared with the intention of releasing them as part of a conservation strategy. Over the last decade, there has been growing interest in the use of environmental enrichment to promote behavioural flexibility in animals that are bred for release. Here, we describe the positive effects of environmental enrichment on neural plasticity and cognition in juvenile Atlantic salmon (Salmo salar). Exposing fish to enriched conditions upregulated the forebrain expression of NeuroD1 mRNA and improved learning ability assessed in a spatial task. The addition of enrichment to the captive environment thus promotes neural and behavioural changes that are likely to promote behavioural flexibility and improve post-release survival.     

Effects of learning experience on behaviour of the generalist parasitoid Sclerodermus pupariae to novel hosts

Massicus raddei Blessig (Coleoptera: Cerambycidae), also referred to as the oak long‐horned beetle (OLB), is a non‐natural host for the generalist parasitoid Sclerodermus pupariae Yang et Yao (Hymenoptera: Bethylidae). To determine whether this generalist parasitoid might be a suitable agent for the control of OLB, the adaptive learning experience of adult female parasitoids to OLB larvae was investigated in the laboratory. A Y‐tube olfactometer bioassay was used to examine the effects of adaptive learning experience on the foraging ability of parasitoids for OLB larvae. The results indicated that parasitoids were significantly attracted by the volatiles of ash bark, Fraxinus velutina, with emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) larvae and larval frass, after exposure to ash bark mixed with EAB larval frass (learning condition A). In contrast, after exposure to oak bark, Quercus liaotungensis, mixed with OLB larval frass (learning condition C), parasitoids showed significant preference for the volatiles of oak bark with OLB larvae and larval frass. On the basis of the results of no‐choice tests, we found that parasitoids exposed to learning condition C had greater paralysis efficiency and higher OLB larvae parasitism rates than those exposed to learning condition A or no experience. Furthermore, parasitoids fed on OLB larvae in learning condition C had significantly greater paralysis efficiency and higher OLB larvae parasitism rates than other parasitoids tested. Parasitoids fed on EAB larvae in learning condition A had the lowest paralysis efficiency and OLB larvae parasitism rates among the parasitoids tested. These findings suggested that adaptive learning significantly enhanced the ability of a generalist parasitoid to utilize a novel host. This may provide a new approach to controlling non‐natural hosts using generalist parasitoids.     

胎次、性别对成年小鼠海马齿状回神经发生及学习记忆的影响

目的探讨胎次、性别是否对成年小鼠海马齿状回神经发生及学习记忆产生影响。方法运用Morris水迷宫系统检测第1～3胎成年小鼠的学习记忆能力,腹腔注射BrdU,标记神经干细胞,检测不同胎次、性别小鼠海马齿状回中的神经发生的差异。结果 （1）在同性别、不同胎次成年小鼠间,第2胎的学习记忆能力（LMA）均显著地高于第1、3胎的,其影响规律为LMA2〉LMA1〉LMA3,且P〈0.05;在同胎次、不同性别成年小鼠间,雌性小鼠的LMA均高于雄性小鼠的,但其差异无显著性（P〉0.05）。（2）在同性别、不同胎次成年小鼠间,第2胎海马DG新生神经细胞的数量（N）均高于第1、3胎的,其影响规律分别为NF2〉NF3〉NF1和NM2〉NM1〉NM3,但其差异无显著性（P〉0.05）;在同胎次、不同性别成年小鼠间,雌性小鼠的N均高于雄性小鼠的,但其差异无显著性（P〉0.05）。结论胎次、性别对实验动物神经发生及学习记忆等方面产生的影响是肯定的。因此,在使用实验动物时,应予以充分考虑,尽量使用胎次、性别相同的。     

Not looking where you are leaping: a novel method of oriented travel in the caterpillar Calindoea trifascialis (Moore) (Lepidoptera: Thyrididae)

The prepupation caterpillar of the Southeast Asian moth Calindoea trifascialis constructs a leaf shelter that jumps across the ground using a jumping method novel among the insects. We found that movement path direction was correlated to the direction opposite to the most intense light. Correlated random walk (CRW) analyses found net squared displacements higher than predicted by a CRW, and fractal dimension analysis indicated straighter paths at large spatial scales. Rearing experiments showed high mortality from predation on the ground, but higher mortality resulted from sun exposure. We interpret jumping path orientation as an efficient search strategy to find shade in a variable landscape, given limited perception, in the presence of overheating and desiccation risks.     

基于应用能力培养的微生物学教学内容优化

微生物学作为生物学科的重要组成部分,是诸多专业的专业基础课程,在不同层次、不同类型、不同专业的高校,其教学基本遵循相同或相似的注重课程理论体系的经典教学模式,该模式不利于普通地方院校本科生应用能力的培养。为此,笔者根据微生物学科研项目思路的构建程序和微生物学实际应用的关键操作技术,以实验项目选择和实验项目顺序调整为突破口,优化微生物学理论和实验教学内容,使两者相辅相成融为一体,以充分发挥专业基础课程在培养学生应用能力方面的作用。     

根际不同供氮水平对紫青菜生长和营养品质的影响

为了解根际供氮对紫青菜(Brassica campestris ssp.chinensis var.communis)生长和营养品质的影响,用不同水平的NH_4NO_3处理,对紫青菜的生理特性和营养品质进行研究。结果表明,随着供氮水平的增加,紫青菜的鲜质量、干质量、根系活力和游离氨基酸含量均呈先上升后略下降趋势;硝酸还原酶(NR)活性、叶绿素含量、NO_3~–含量和可溶性蛋白质含量均呈上升趋势;DPPH·自由基清除率、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)同工酶和过氧化氢酶(CAT)同工酶活性等均提高;而花青素苷相对含量、可溶性糖含量、维生素C(Vc)含量、总酚含量和FRAP值均呈下降趋势。根际NH_4NO_3为75~300 mg L~(–1)时,紫青菜的鲜质量和干质量较低;NH_4NO_3达1200 mg L~(–1)时,其鲜质量和干质量又低于600 mg L~(–1)处理的,植株积累较多NO_3~–,导致营养品质下降,同时根际也积累NH4NO3。因此,600 mg L~(–1)的根际NH_4NO_3是适宜的氮水平,其鲜质量和干质量均最高、营养均衡、抗氧化能力强。     

便携式运动能力检测系统的研制

目的:检测儿童的平衡能力和下肢力量,研究评估儿童运动能力的相关指标。方法:设计了一套便携式运动能力检测系统,检测儿童的平衡能力和下肢力量。本系统由运动能力检测设备和上位机数据分析存储展示部分组成。结果:研制的便携式运动能力检测系统具有可穿戴、功耗低等优点,能够准确地记录儿童的运动数据。结论:便携式运动能力检测系统能够检测使用者在运动过程中的平衡数据和下肢力量数据,及时发现运动能力的缺陷,为儿童的日常生活和锻炼提供参考。     

韭菜迟眼蕈蚊雄虫日龄对其交配能力和雌虫生殖力的影响

为了提高韭菜迟眼蕈蚊性信息素监控水平,本文在25℃、RH70%±5%、光周期L∶D=14∶10的条件下研究韭菜迟眼蕈蚊不同日龄雄虫的交配能力及其对雌虫生殖力的影响。结果表明,未交配雄虫平均寿命4.5d,雌虫4.2d,雌雄成虫的平均寿命无显著差异。雄虫一生最多可交配13次,且随着雄虫日龄增加,雌虫交配成功率逐渐减少。随着雄虫交配经历的增加,雌虫交配的时间延长,最长达97min。雄虫的日龄并不影响与之交配雌虫的产卵量和卵孵化率,但是雄虫的交配经历与雌虫的产卵量和卵孵化率相关,尤其当雄虫交配经历超过8次时,与之交配的雌虫的产卵量和卵孵化率显著下降。研究阐明了韭菜迟眼蕈蚊的生殖行为特征,为其性信息素应用提供了参考。     

Antioxidant capacities in various animal sera as measured with multiple free-radical scavenging method

Scavenging abilities of animal sera against six reactive species (OH, O₂⁻, RO, t-BuOO, H₃C, and ¹O₂) were determined with the use of multiple free-radical scavenging (MULTIS) method. Commercially available sera from pig, horse, rabbit, Guinea pig, hamster and chicken were subjected to MULTIS analysis and the results were compared with human specimen. In general, animal sera showed lower scavenging ability against OH and RO radicals than human serum. However, it is noteworthy that rabbit and chicken sera have higher scavenging ability against O₂⁻ than others. This is consistent with the known data that superoxide dismutase levels in these sera are high. In addition, we determined the uric acid level in animal sera using the uricase-TOOS method. In chicken serum, uric acid was found to be the major effective component in RO scavenging. This paper is first to quantitatively evaluate antioxidant capacities in animal sera.