Water quality and phytoplankton stability in response to application frequency of bioaugmentation agent in shrimp ponds

Splitting the recommended weekly dosage of bioaugmentation agent and applied at varying frequencies were tested to determine its effects on water quality and phytoplankton stability in tiger shrimp (Penaeus monodon) grow-out ponds. The supplier's recommended weekly dosage was followed but at varying application frequencies namely: once per week, twice per week, and four times per week for the duration of 120 culture days. A treatment with no bioaugmentation was added as control. Results showed that ammonia and particulate organic matter levels were significantly lower and plankton die-off was greatly minimized if the product was applied four times a week application compared with twice a week and weekly applications. Significant reduction in the number of luminous Vibrio species was observed in ponds with more frequent applications than those with less. For shrimp, survival and production were significantly higher in ponds with twice and four times per week applications compared to the weekly application and the control (P < 0.05). Results of this study indicate that splitting the weekly dosage of bioaugmentation agent and applying it four times per week is highly beneficial and ideal for shrimp culture.     

半散养东北虎非繁殖期与发情交配期的行为时间分配

[目的]研究东北虎在非繁殖期和发情交配期活动节律的差异,以及其活动节律之间是否存在性别差异。[方法]采用行为取样法对7只(3雌4雄)东北虎的发情交配期和非繁殖期进行了观察。[结果]东北虎发情交配期的主要行为包括休息、运动和发情交配,其中雌虎在发情交配期和非繁殖期休息和运动时间差别不大,而雄虎发情交配期的休息时间较非繁殖期明显下降,运动差异不明显;雌雄虎在非繁殖期和发情交配期的休息、运动和发情交配时间没有明显的性别差异。[结论]结果为优化东北虎的管理及提高其繁殖成功率提供了参考。     

虎血液生理生化值研究概况

虎的血液生理生化指标可以反映虎健康状况。处于不同生长发育时期和不同状态的老虎在血液生理及生化指标值上差异较大,部分指标值具有统计学意义,可以作为不同亚种虎以及虎是否健康的判断参考指标。     

东北虎豹国家公园黑龙江东宁片区人兽冲突现状调查分析

针对人兽冲突现状、补偿情况、野生动物保护态度等问题,通过入户访谈、调查问卷的方式对东北虎豹国家公园东宁片区两个乡镇5个村屯的居民进行了调查。结果显示,发生冲突率47.28%,人兽冲突形式有粮食减产、捕食家畜和人身伤害,造成损害的野生动物物种主要包括野猪、黑熊、东北虎、东北豹、马鹿和狍。造成的平均经济损失为8796.9元/年,其中农牧业损失最大,为10373.3元/年。但大部分野生动物损害未能得到补偿,仅1户得到了1000元的补偿款。人兽冲突的预防和缓解措施包括:规范当地居民的生产生活行为,禁止非法狩猎、在禁牧区放牧等活动;对东北虎及其他重点保护野生动物造成的损害采取经济补偿办法,建立东北虎损害保险制度;加强宣传,提高居民对东北虎等野生动物的保护意愿。     

Effects of dietary mannan oligosaccharide on growth, body composition and hepatopancreas histology of Penaeus semisulcatus (de Haan 1844)

The effects of dietary mannan oligosaccharides (MOS) on growth, body composition and hepatopancreas histology of Penaeus semisulcatus (postlarvae stage 20) were investigated for 48 days. Different dosages of MOS (0, 1.5, 3.0 and 4.5 g MOS kg⁻¹) were tested in triplicate groups. Shrimp postlarvae averaging 0.34 ± 0.01 g attained 1.52 ± 0.31, 1.51 ± 0.15, 2.18 ± 0.13, 1.57 ± 0.13-g final weight and 42.7 ± 2.7, 37.3 ± 1.3, 64.0 ± 6.9, 50.7 ± 4.8% survival, respectively. At the end of the study, generally enhanced growth performance and feed conversion ratio were observed in shrimp fed on diet containing 3.0 g kg⁻¹ MOS with the highest final live weight (2.18 ± 0.13 g) and survival rate (64.0 ± 6.9%) after 48 days of feeding. The protein contents in the whole body decreased with increasing rates of dietary MOS (P < 0.05). Different levels of dietary MOS used in this study showed no detrimental effects on hepatopancreas tissue judged by histological screening. In conclusion, 3.0 g kg⁻¹ MOS could be used as a healthy growth promoter in shrimp diets.     

明清时期江西境内的虎患及相关问题研究

历史时期，江西地区是华南虎的主要栖息地之一。然而，随着人类活动的加强和自然环境的变迁，人虎关系在明清时期表现得异常紧张，“虎患”问题成为地方政府头疼的灾害之一。以往学者在研究江西虎惠时，只是单方面强调人类无休止的开发活动压迫了虎的生存空间，最终导致虎患的发生。事实上，一些经济、文化水平较高的地区也是虎患高发地。究其原因，乃为战乱、灾荒导致人口锐减、社会残破和田地荒芜，次生林在战乱、灾荒之后得到恢复并成为战后较长一段时间内的主要植被，为虎提供了广阔的栖身之所，从而诱发了群虎入城袭击人类的事件发生。     

幼龄华南虎的人工饲养

华南虎幼崽为晚成哺乳动物,刚出生时双眼未睁、不能独立取食和排便,需要人工辅助其学习和完成。初生仔兽的喂饲以少量多食为佳,前3 d以7～8次较为适宜,喂奶量由少增多。饲喂幼虎时人工奶的初始浓度以1：8较适合。幼兽需要用纱布蘸水轻擦仔兽的肛周,以刺激其排便。在8周龄左右为幼虎添加肉浆,1个月后将肉浆替换为肉条。肉类食物的添加时间为观察到幼虎牙齿长出,此时喂奶量可以随着肉量的增加而逐渐减少,直至完全断奶。饲料转换过程中,动物对人工奶的取食量逐渐下降,并且在1周内会出现身体不适,体重增长减缓,一般持续5～7 d即恢复正常。动物对肉条适应以后,而对人工奶的需求量急剧下降,此时可以增加骨头以锻炼幼兽的啃食能力,此时幼兽的体重迅速上升。     

Patterns of spatiotemporal change in large mammal distribution and abundance in the southern Western Ghats, India

Large mammals face high risks of anthropogenic extinction owing to their larger body mass and associated life history traits. Recent worldwide mammal declines have highlighted the conservation importance of effective assessments of trends in distribution and abundance of species. Yet reliable data depicting the nature and extent of changes in population parameters is sparse, primarily due to logistical problems in covering large areas and difficulties in obtaining reliable information at large spatial scales, particularly over time. We used key informant surveys to generate detection histories for 18 species of large mammals (body mass > 2 kg) at two points in time (present and 30 years ago) in the Southern subregion of the Western Ghats global biodiversity hotspot. Multiple-season occupancy models were used to assess temporal trends in occupancy, detectability and vital rates of extinction and colonization for each species. Our results show significant declines in distribution for large carnivores, the Asian elephant and endemic ungulates and primates. There is a significant decline in detectability for 16 species, which suggests a decline in their abundance. These patterns of change in distribution and abundance repeat in our assessments of spatial variation in occupancy dynamics between the three contiguous forest complexes and two human-dominated landscapes into which the southern Western Ghats has been fragmented. Extinction rates are highest in the human-dominated landscapes. Declines in abundance for several species suggest the presence of extinction debts, which may soon be repaid with imminent range contractions and subsequent species extinctions unless immediate remedial conservation measures are taken. Detection/non-detection surveys of key informants used in an occupancy modeling framework provide potential for rapid conservation status assessments of multiple species across large spatial scales over time.     

浅谈野生虎生态学研究

虎在生态系统中处在食物链的顶端，是自然保护中的旗舰物种，具有重要的生态价值和科学价值。目前，虎的分布范围及数量已经明显减少，成为最受威胁的大型猫科动物之一。针对虎的这种濒危状况，虎的研究得到了极大关注，尤其是野生虎的生态学研究。本文综述了野生虎生态学的研究，从野生虎生态学的研究历史出发，作者认为野生虎的保护应该做到以下几点：减少人为干扰；保护好现有虎栖息地，对现有虎种群实行异质种群管理；建立新的保护区，扩大虎的栖息地；设法扩大虎猎物种群的数量。     

江蓠、浒苔、藻渣和菌渣替代鱼粉对红鳍东方鲀幼鱼生长性能、相关生化指标的影响

本实验旨在研究江蓠(Gracilaria verrucosa)、浒苔(Enteromorpha prolifera)、藻渣和菌渣替代鱼粉对红鳍东方鲀(Takifugu rubripes)幼鱼生长性能、血清和肝脏生化指标和体组成的影响。实验共制成6种等氮、等脂的饲料,以含鱼粉60%为对照组1和45%鱼粉的为对照组2,分别将10%的江蓠、浒苔、藻渣、菌渣与植物蛋白质配合后替代对照组1饲料中30%的鱼粉,投喂初始体重为(17.33±0.55) g的红鳍东方鲀幼鱼56 d。结果显示,1)浒苔组特定生长率(SGR)显著高于其他5组(P<0.05),藻渣组SGR显著高于对照组2和江蓠组(P<0.05),与对照组1和菌渣组无显著差异(P>0.05);对照组1和浒苔组饲料效率(FER)显著高于对照组2和菌渣(P<0.05),与江蓠和藻渣组无显著差异(P>0.05);对照组1的蛋白质沉积率(PPV)和蛋白质效率(PER)显著高于对照组2和菌渣组(P<0.05),与江蓠、浒苔和藻渣组无显著差异(P>0.05)。2)各组血清和肝脏中谷丙转氨酶(GPT)和谷草转氨酶(GOT)活性均无显著差异(P>0.05)。各组血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性均无显著差异(P>0.05)。3)菌渣组鱼体粗蛋白质含量显著高于藻渣组(P<0.05),与对照组1、对照组2、江蓠和浒苔无显著差异(P>0.05);浒苔和藻渣组鱼体粗脂肪含量显著高于对照组2 (P<0.05),与对照组1、江蓠和菌渣组无显著差异(P>0.05)。综合来看,将10%江蓠、浒苔、藻渣和菌渣与植物蛋白质配合后替代饲料中30%的鱼粉对红鳍东方鲀幼鱼的生长性能无不良影响,并且浒苔可以显著提高红鳍东方鲀的生长性能。