人工哺育大熊猫幼仔1月龄内的饲喂及体重增长变化研究

人工圈养大熊猫出生幼仔一般采用自然哺育和人工哺育2种形式。人工哺育大熊猫幼仔1月龄内的饲喂及体重增长变化研究结果表明,3只研究个体均饲喂异母初乳时,其生长发育良好。经方差分析,3只幼仔1月龄内饲喂和体重变化均无显著差异。因圈养大熊猫产双胎的几率较大,所以采取人工哺育可以保证幼仔的成活率。目前人工哺育的方式主要是采集初乳及母乳和配制人工乳来进行人工育幼。     

豚草和三裂叶豚草拮抗植物的筛选

【目的】 研究豚草(Ambrosia artemisiifolia L.)和三裂叶豚草(Ambrosia trifida L.)浸提液对常用替代牧草高羊茅、早熟禾、黑麦草、披碱草,以及对苜蓿、葵花、玉米、小麦、甜菜种子萌发的影响;筛选对豚草和三裂叶豚草具有防控效果的替代植物以及最佳混种方式。【方法】 采用培养皿滤纸法,研究豚草和三裂叶豚草浸提液对供试种子萌发的影响。采用盆栽竞争试验,运用DeWit取代试验研究法,设置牧草和入侵杂草5种混种方式,混种比例分别为1∶1、1∶2、1∶3、2∶1、3∶1,研究黑麦草、披碱草和高羊茅与豚草和三裂叶豚草的竞争效应,分析3种牧草对豚草和三裂叶豚草的替代控制潜力。【结果】 随着豚草和三裂叶豚草的浸提液浓度的增加,4种常用替代牧草种子和新源县5种主要作物种子发芽率,发芽指数和化感效应指数均下降。5种混种密度下,黑麦草、高羊茅与三裂叶豚草混种比例为3∶1时,三裂叶豚草的竞争平衡指数分别为(-0.505 1±0.301 5)、(-0.757 6±0.265 88)均显著小于0(P<0.05);黑麦草、高羊茅与豚草混种比例为1:3时豚草竞争平衡指数分别为(-0.955 8±0.518 08)、(-2.049 7±0.178 55)均显著小于0(P<0.05)。【结论】 豚草和三裂叶豚草浸提液对供试种子萌发具有化感抑制作用;且浸提液浓度越大抑制作用越强,同时叶部化感抑制作用大于根部。三裂叶豚草对四种牧草种子萌发的化感抑制作用大于豚草。黑麦草和高羊茅可以作为豚草和三裂叶豚草的替代植物。黑麦草和高羊茅防治三裂叶豚草时建议播种比例为3∶1;防治豚草时建议播种比例为1∶3。豚草和三裂叶豚草发生密度较大时其化感抑制作用越强,影响牧草萌发生长,应适当加大替代牧草播种量。     

Cytologic findings from a benign giant cell tumor of the tendon sheath in a dog

A 6‐year‐old male neutered Australian Shepherd dog was presented for evaluation of a subcutaneous mass on the plantar aspect of the proximal left metatarsus. Fine‐needle aspirate smears contained numerous plump spindle cells and large multinucleated cells amongst a considerable amount of pink extracellular matrix. Histopathologic diagnosis of the tissue obtained during initial biopsy and eventual surgical cytoreduction of the mass was a benign giant cell tumor of the tendon sheath (GCTTS). Immunohistochemically, the synovioblastic neoplastic cells were diffusely strongly positive for vimentin and S‐100, were multifocally moderately positive for cytokeratin AE1/3, and were negative for CD18, muscle‐specific actin (MSA), and melanoma‐associated antigen (mutated) 1 (MUM‐1). The dog recovered from surgery and underwent definitive radiation therapy to treat the local residual disease. Eight months later, the mass had not recurred. The diagnosis of GCTTS in this case supports previously published reports describing GCTTS as a relevant disease entity in dogs, and provides the first documentation of cytologic findings with this tumor. Further investigation is needed to correlate pathologic features with clinical behavior and response to therapy in dogs.     

Comparison of larval performance between Thai and Vietnamese freshwater giant prawn, Macrobrachium rosenbergii (de Man): a preliminary study

This study compared the performance of larvae of giant freshwater prawn (Macrobrachium rosenbergii) from Thailand and Vietnam. Thai broods were collected from a farm and Vietnamese broods were collected from a river. Larvae from these two sources were raised in identical environments, and their rates of development and survival as well as their ability to withstand environmental stresses were assessed. The first postlarval stage was observed in both strains on day 22. All larvae (100%) from Thai broods completed metamorphosis by day 36, but only 89% of the Vietnam strain completed metamorphosis by day 45. The stages of development were more uniform in larvae from the Thai stock than the Vietnamese stock. Survival differences were observed within the first week (92% in the Thai group vs. 55% in the Vietnamese group). These differences were most pronounced beginning in week 5 (52% and 16% respectively) and week 7 (33% and 2% respectively). No clear difference was found in brood size and fecundity between the two groups. No difference in survival was observed between the two groups of larvae challenged with salinity, oxygen or formalin. Differential development rates of larvae in the same batch would naturally create conditions favourable for cannibalism and impaired ability to capture food. The earlier and more uniform rate of development, and subsequent higher rate of survival of Thai stock compared with the Vietnamese wild stock is suggested to be due to inadvertent selection in the domesticated stock.     

Culture of Macrobrachium rosenbergii (De Man 1879) in experimental cages in a freshwater eutrophic lake at different stocking densities

Macrobrachium rosenbergii (de Man 1879) juveniles (0.4 g) were cultured in experimental cages (L × W × H: 2.5 × 1 × 1 m) in Laguna de Bay, the largest lake in the Philippines. The following stocking densities at four replicates each were used: 15, 30, 60 and 90 prawns m⁻² of cage bottom. The mean sizes at harvest after 5 months of culture ranged from 14.3 g for the highest stocking density to 26.3 g for the lowest. The mean size at harvest, daily growth rate and size class distribution were significantly influenced by stocking density, with those at the lowest stocking density showing significantly better growth and overall proportion of larger prawns. Heterogeneous individual growth (HIG) was fairly evident in all treatments. The percentage of blue‐clawed males was not influenced by treatment but the mean weight was significantly higher in the lower stocking densities. Both the percentage and mean weight of berried females were significantly higher in the lowest stocking density. Survival was the highest in the lower stocking densities (55.3%, 54.0%, 52.7% and 36.9% for 15, 30, 60 and 90 prawns m⁻² respectively). Feed conversion ratio (FCR) improved with decreasing stocking density, ranging from 2.1 to 3. As expected, yield per cropping increased with stocking density and ranged from 450 to 1089 g m⁻² yr⁻¹ of actual cage area. Production values obtained in the cage cultured M. rosenbergii were comparable to or even higher than those reported from pond culture, given that the stocking densities used in this study were generally higher than in ponds. The results show that the farming of M. rosenbergii in cages in lakes is a viable alternative to pond culture and has the potential of improve aquaculture production in lakeshore fish farming communities.     

籼稻巨胚不育系龙特浦geA的选育

通过辐射诱变获得籼稻保持系龙特浦B巨胚隐性单基因突变体 (龙特浦geB) ,为龙特浦B的巨胚同型系 ,主要农艺性状无明显差异 ,但绝对胚重和相对胚重分别由原龙特浦B的 0 63mg和 2 78%提高到 1 1 5mg和 6 0 7% ,从而糙米粗脂肪含量由 2 50 %提高到 5 0 6% ,蛋白质由 9 0 0 %提高到 9 60 % ,各种氨基酸含量的相对值也相应提高 5 45%～ 3 0 3 6% ;用龙特浦geB回交龙特浦A育成巨胚不育系龙特浦geA ,其与龙特浦A的主要农艺性状、雄性育性特征及构成产量配合力无明显差异。     

基于野生动物适宜栖息地的保护区网络规划——以秦岭大熊猫保护区为例

不合理规划是我国目前自然保护区面临问题的主要原因,通过对秦岭大熊猫保护区网络内适宜栖息地的评估,发现秦岭大熊猫保护区网络没有基于适宜栖息地的生物边界进行科学规划,导致各保护区内大熊猫的生存环境质量差异巨大,造成目前秦岭大熊猫保护区网络功能不均衡,影响其效率和保护成效。适宜栖息地是保护区境内具有保护贡献的土地,是体现保护区功能的区域,是保护区及网络规划的核心。基于适宜栖息地的保护区网络规划和优化能提高我国保护区及网络的功能和效率,减少保护的土地成本,能有效缓解保护与发展的矛盾。     

罗氏沼虾消化系统组织学的光镜与扫描电镜观察

本文进行了罗氏沼虾（Macrobrachiumrosenbergii）消化系统的光镜组织学和扫描电镜研究。观察发现，罗氏沼虾的贲门胃内无齿，胃壁背、腹面的一定部位有角质板的特殊结构。中肠很长，占据头胸部的后半部分和腹部的大部分；中肠上皮细胞的游离端和中肠腺小管细胞的游离端均有纹状缘，无角质膜。后肠很短，无纹状缘。消化道上皮细胞有无纹状缘是区分中肠与前、后肠的重要标准之一。