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1.
An enriched environment is widely used to improve domestic animals’ welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.  相似文献   
2.
本研究旨在探明鸡恒定链(invariant chain,Ii)与内吞体转运蛋白Rab5a和Rab7b结合的结构域和在细胞内共定位的特征。首先,用PCR和基因突变技术将Ii胞浆区与跨膜区[Ii(Cyt-Tra)]、Ii CLIP (class Ⅱ-associated invariant chain peptide)-三聚体区[Ii(CLIP-TRIM)]和Ii突变体[Ii(M81-87aa)、Ii(M91-99aa)和Ii(M81-99aa)]分别插入pET-32a和pEGFP-C1构建相应的原核和真核重组质粒。其次,将构建的含有绿色荧光蛋白的重组质粒与实验室保存的含有红色荧光Rab5a和Rab7b的重组质粒共转染至人胚胎肾细胞系293 T,观察它们的共定位。将构建的原核重组质粒进行表达和纯化,最后用拉下法和免疫印迹检测Ii与Rab5a和Rab7b的结合域。结果表明,成功构建Ii结构域及Ii突变体的重组质粒。Ii(Cyt-Tra)及Ii突变体均能与Rab5a和Rab7b在细胞内共定位,而Ii(CLIP-TRIM)与空载体却不能。Ii的胞浆区和跨膜区是与Rab5a和Rab7b结合的功能结构域,而不是CLIP与三聚体区。综上所述,鸡Ii与Rab5a和Rab7b共定位和结合的区域是其胞浆区和跨膜区,而不是内质网腔区。这些结果提示Rab分子参与了Ii在胞内细胞器的转运机制,为进一步研究Ii及其载体在细胞内的转运机制和功能提供了新的途径。  相似文献   
3.
在丛生竹林下对不同基质配方和硒浓度菌棒进行埋棒栽培以及覆土方式栽培试验,结果表明,菌棒不同基质配方对竹荪产量及其营养成分有显著影响,而且三列浅沟形和双列龟背形2种覆土方式有利于提高竹荪产量。改良基质配方菌棒竹荪产量比常规配方提高约50%;在添加外源硒质量分数为0~2.0 mg/kg的浓度范围内,竹荪子实体产量先随着硒浓度的增加而逐渐增加后再有所降低,基质中添加1.5 mg/kg硒肥比不添加产量提高了195.30%。基质中添加硒质量分数为1.0~2.0 mg/kg的硒肥可以较显著地提高竹荪花的硒含量,其干物质中硒含量平均值从约2.50 mg/kg提高到8.05~13.30 mg/kg,外源硒肥利用率达到9.70%~15.36%。菌棒不同基质配方对竹荪子实体的粗蛋白及粗多糖含量有明显影响,改良配方竹荪蛋与竹荪花的粗蛋白含量是常规配方的1.21和1.29倍,其粗多糖含量是常规配方的4.81和1.35倍;基质中添加硒肥与不添加硒肥相比,竹荪蛋与竹荪花中粗蛋白含量分别增加了40.90%和14.30%。在硒质量分数为1.0 mg/kg的竹荪菌棒林下覆土栽培试验中,三列浅沟形覆土方式单位面积鲜竹荪蛋产量最高,为10.27 kg/m2;双列龟背形覆土方式单个菌棒的鲜竹荪蛋产量最高,达1.40 kg。三列浅沟形和双列龟背形2种覆土方式基质生物转化率分别为93.00%和94.14%,达到了较高水平。  相似文献   
4.
不同施肥处理对马铃薯农田土壤理化性状及产量的影响   总被引:1,自引:1,他引:0  
为了探究不同施肥处理对马铃薯农田土壤理化性状及产量的影响,试验地采用马铃薯连作模式,设置3个施肥处理,即:单施化肥(T)、有机肥配施化肥(YTF 1/2)、全量有机肥(YTF)。结果表明:在不同施肥处理下马铃薯农田土壤的理化性质和马铃薯产量发生了变化,其中变化最为明显的土壤指标有土壤容重、孔隙度、饱和导水率、有效磷。YTF处理较T处理可分别显著(P<0.05)降低土壤容重16.8%,增加土壤孔隙度12.7%,提升饱和导水率25.3%。YTF处理可显著提升土壤有效磷含量43.0%,但各处理间土壤pH、有机碳、全氮、全磷、碱解氮、速效钾之间差异并未达到显著水平。同时,较之T处理,YTF处理亦可显著提升土壤团聚体含量。YTF和YTF 1/2处理可分别较T处理提升马铃薯产量24.6%和12.8%。因此,施用有机肥不仅可以改善土壤结构,改良土壤物理性状,亦能促产增收。  相似文献   
5.
近年来象耳豆根结线虫的危害日益严重.为筛选抗象耳豆根结线虫的辣椒种质,本试验利用种属特异性引物对根结线虫病原物开展分子鉴定,确定为象耳豆根结线虫.接着采用室内人工接种法,对10份一年生辣椒种质和10份中国辣椒种质进行象耳豆根结线虫抗性鉴定,计算根结指数和卵粒指数,并通过比较隶属函数,发现其中3份辣椒种质对象耳豆根结线虫表现为高抗,抗病性最强的是L518M和L525-1M,L42M次之;10份表现为中抗;7份表现为感病,抗病能力最弱的是L69-1M;未发现免疫品种.本研究发现中国辣椒种质的抗病性整体高于一年生辣椒,是重要的抗病种质来源,可用于象耳豆根结线虫抗病育种和后续抗病机理的研究.  相似文献   
6.
旨在满足马铃薯生产中茬口衔接、机械化生产技术应用、不利气候下稳产等对马铃薯出苗早、齐、壮的需求,以‘费乌瑞它’为供试品种,用基于有益活菌或工程菌提取物的5种生物制剂进行种薯处理,对多重性状进行了对比分析。5种生物制剂较常规化学制剂,均能够不同程度地促进种薯萌芽和芽根同生,出苗期提前2~7天,播种后49天的出苗率提高3.33%~17.78%。其中,表现最好的为酵母核苷酸衍生物和VDAL,种薯萌发和生根均显著高于对照。霜冻后,生物剂拌种处理在恢复前期促进植株生长,由此促进恢复后期的块茎发育,较常规化学处理增产8.39%~24.03%,体现了不同程度的保产效果。多马道黑、酵母核苷酸衍生物、根肽和VDAL体现出较好的保产效果,可作为种薯处理剂投入马铃薯生产。  相似文献   
7.
为探明长江中游玉米籽粒机械直收适宜品种与配套农艺措施,2018—2019年选用不同玉米品种,测定不同机收时间下玉米关键农艺性状、产量及机收质量指标。结果表明,收获时间对春玉米机收产量与机收质量均有显著影响。延迟1周收获后籽粒容重显著增加,机收产量显著提高,2年平均提高9.72%;而延迟2周收获则有降低机收产量的趋势。2年收获时杂质率总体≤3%,而机收籽粒破碎率与损失率均>5%,是该区域春玉米籽粒机收面临的主要问题。籽粒厚度、籽粒含水率和百粒重是影响机收籽粒破碎率的关键性状,三者与机收籽粒破碎率均呈显著的倒二次曲线关系;玉米的倒伏率、穗位高和重心高度是影响机收损失率的关键性状,倒伏率与机收损失率呈显著正相关,而穗位高和重心高度与机收损失率均呈显著的二次曲线关系。延迟收获能显著降低籽粒含水量,从而降低籽粒破碎率,但继续延迟收获有增加倒伏的风险。综上,长江中游春玉米成熟后适时延迟7~10 d收获,可有效降低籽粒含水量与机收籽粒破碎率,提高玉米籽粒机收产量。  相似文献   
8.
喆茗 《茶叶》2018,(1):51-55
斯里兰卡茶产业对推动本国经济发展具有重要作用,政府高度重视并制定了产业政策。斯里兰卡茶业发展迅速,但也面临诸多问题。本文分析了斯里兰卡茶业的发展现状及存在的主要问题,提出了斯里兰卡茶业未来发展的方向。  相似文献   
9.
Carbon storage in the soils on the Qinghai–Tibetan Plateau plays a very important role in the global carbon budget. In the 1990s, a policy of contracting collective grasslands to smaller units was implemented, resulting in a change from the traditional collective grassland management to two new management patterns: a multi‐household management pattern (MMP: grassland shared by several households without enclosures) and a single‐household management pattern (SMP: grassland enclosed and used by only one household). In 2016, 50 MMP and 54 SMP winter pastures on the Qinghai–Tibetan Plateau were sampled to assess the differences in soil organic carbon (SOC) between the two management patterns. Results showed that average SOC was significantly greater under MMP than under SMP, with an estimated 0.41 Mg C/ha/yr lost due to SMP following the new grassland contract. Based on the government's grassland policy, four grassland utilization scenarios were developed for both summer and winter pastures. We found that if the grassland were managed under SMP, likely C losses ranged between 0.31 × 107 and 6.15 × 107 Mg C/yr across the Qinghai–Tibetan Plateau relative to MMP, which more closely resembles pre‐1990s grassland management. Previous estimates of C losses have only considered land use change (with cover change) and ignored the impacts driven by land management pattern changes (without cover change). The new data suggest that C losses from the Qinghai–Tibetan Plateau are greater than previously estimated, and therefore that the grassland contract policy should be reviewed and SMP households should be encouraged to reunite into the MMP. These findings have potential implications for land management strategies not only on the Qinghai–Tibetan Plateau but also other grazing regions globally where such practices may exist.  相似文献   
10.
The important root characteristics of root length density (RLD) and root mass density (RMD) generally differ among irrigation managements and potato cultivars. The objective of this study was to investigate the RLD and RMD variations and their functional relationships with gross potato tuber yield for two commercial potato cultivars, Agria and Sante, under different irrigation strategies. Full irrigation and water‐saving irrigation strategies, deficit and partial root drying irrigations, were applied statically (S) and dynamically (D) based on daily crop evapotranspiration. Results showed that SPRD had significantly greater RLD (3.64 cm/cm3) and RMD (132.7 μg/cm3) than other irrigation treatments. Between the potato cultivars, Agria had significantly larger values of RLD (3.50 cm/cm3) and RMD (138.7 μg/cm3) than Sante. The functional relationship between the root growth characteristics and tuber yield showed that under water‐saving irrigations, Agria increased root mass at the expense of gross tuber yield but Sante increased root mass to maintain larger gross tuber yields. However, Agria produced more roots and gross tuber yield than Sante, and it is concluded that Agria is a more drought‐tolerant potato cultivar, which is recommended for tuber production in regions where water might be scarce. It was shown that larger root production in potatoes was associated with improved tolerance to water stress.  相似文献   
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