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1.
重新蓄水后的白洋淀鲫鱼的生物学分析 总被引:2,自引:1,他引:2
本文论述了重新蓄水后白洋淀鲫鱼的食性、年龄生长和繁殖。鲫鱼主要以硅藻、枝角类和水生维管束植物为食。可分为五个年龄组,平均肥满度为3.1324,Ⅱ-Ⅲ龄组生长最快、最好。绝对怀卵量为5127~61596粒,相对怀卵量为72.54~402.59粒/克,性腺成熟系数为4.293%~13.072%。 相似文献
2.
本标准依据家养麝的常用饲料营养成分、消化、代谢和饲养试验结果的大量资料制定。包括仔麝、育成雌雄麝、成年雌雄麝和繁殖雌麝等七种饲养标准。按本标准饲养大群雌麝的繁殖率比对照组提高34%,雄麝的麝香产量比对照组提高19%。 相似文献
3.
虎纹蛙(Rana tigerina rugulosa)的食性与繁殖习性的研究 总被引:3,自引:1,他引:3
本文研究报道虎纹蛙(RanatigerinarugulosaWiegmann)的生态习性特点.该蛙性凶猛,蝌蚪以活的小动物为主食,也会互相残杀,成体则喜吃昆虫和蟛蜞;繁殖期为4~8月,高峰期为4月下旬~5月中旬;属于一年多次产卵类型;卵群形态为小片状,沿着水域的岸边分布;个体发育迅速,春末夏初产卵发育而成的雄蛙,在当年冬眠之前可达性成熟. 相似文献
4.
鄱阳湖产太湖短吻银鱼以枝角类、桡足类等浮游动物为主要食料.它们天亮开始摄食,夜间停止,白天连续摄食,其援食速度和消化速度都很快.晴天摄食多,雨天摄食少.周年内,在6、10—11、3月份三次出现摄食高峰.正在产卵的雌鱼停止摄食,产卵后,摄食量又大增. 相似文献
5.
黑鲷化学感觉发育和摄食关系 总被引:4,自引:0,他引:4
研究了黑鲷(Sparusmacrocephalus)仔、稚、幼鱼嗅觉和味觉器官的基本结构及嗅觉、味觉与摄食的关系,初孵仔鱼的嗅囊很小、很浅,细胞没有分化。5d的嗅囊细胞开始分化,24d嗅囊分化完毕,嗅觉开始功能化,参与摄食反应。初孵仔鱼味蕾没分化,5d的仔鱼味蕾分化形成,参与摄食反应。随发育的进行,先后从口咽腔、头部、躯干、尾部、鳍等处依次出现味蕾。嗅觉和味觉是鱼类的化学感觉,嗅觉可以对远、近距离的食物发生反应,而味觉只能对接触的或几乎接触的食物发生反应。化学感觉对摄食的作用是对黑暗条件下视觉摄食的补充。 相似文献
6.
本文研究了坑道内3-5cm皱纹盘鲍(HaliotisdiscushannoiIno)的摄食习性。结果表明:随海水温度变化,鲍日摄食量呈明显曲线关系,以春末夏初日平均摄食量最大;光线长期在黑暗(光强〈50Lux)条件下,鲍能改变自然习性而昼夜摄食;在坑道内,3.5cm规格皱纹盘鲍生长最快,饵料系数最低;鲍对不同种海藻饵料表现出明显选择性,按喜好程度依次排列为裙带菜、海藻、石莼、鼠尾藻和羊栖菜,鲍较喜食叶片状海藻,对枝条状海藻则不太喜好。 相似文献
7.
《Journal of Natural History》2012,46(10):1447-1483
In the present study we investigate the trophic behaviour, stomach content and morphology of the feeding appendages, with emphasis on setae, of two callianassids; a generalist feeder, Callichirus major (Say, 1818) and a strict deposit feeder, Sergio mirim (Rodrigues, 1971). Of the 87 setal types described, only 5% were common to both species. Setal types were clustered in four main categories; plumed, serrate, plumodenticulate and simple. Callichirus major has higher setal diversity than S. mirim. Relative to the amount of setal types present in each species, C. major has a higher ratio of serrate to plumodenticulate setal types and similar percentages of plumed and simple setae. Examining the setae and spatial position of the segments of the feeding appendages, it is possible to infer that the main function of the dactyli, propodi and basal endites is to brush particles, while the meri, ischia and coxal endites retain sediment. The setal diversity found on the feeding appendages reflected the diverse trophic strategies of the callianassid species studied. Exclusive deposit feeders, e.g. S. mirim, appear to have fewer setal types than generalist feeders, e.g. C. major. Apparently, the higher ratio of serrate to plumodenticulate setal types in Callianassidae depends more on the necessity to triturate particles prior to ingestion than on the trophic mechanism used by the species. 相似文献
8.
《Journal of Natural History》2012,46(5-8):293-312
Over 4 years, daily counts recorded 830 Microplana scharffi, 2752 M. terrestris, and 108 of an unknown khaki Microplana species under wood, concrete, polythene, and a plank at a shaded site in a domestic garden. Numbers peaked in July and August. Microplana scharffi more often occurred under polythene, M. terrestris and the khaki species more often under wood. Cocoons peaked in June and July and hatchlings between July and September. Twelve M. terrestris cocoons yielded 50 hatchlings. Three M. scharffi cocoons yielded eight hatchlings. The time taken to hatch reduced from February to August. Earthworms accounted for 87% of M. scharffi prey. Microplana terrestris consumed earthworms, Arion hortensis and Discus rotundatus. Hatchling and unfed M. scharffi were yellow or cream. Fed individuals varied from pink to pale brown, depending on prey colour. 相似文献
9.
《Journal of Natural History》2012,46(1):7-13
Summary The discovery of Serolis tropica sp. nov. in the shallow shelf zone of the Pacific of Panamá, just south of 9°N latitude, establishes the first occurrence of the Serolidae in tropical American waters. Since gravid females were found in cool as well as warm thermal seasons, it is assumed that this species is adapted to live under tropical conditions. Serolis yongei, known from the Great Barrier Reef, was collected at a depth of 200 m. It is not presently known if this species, like S. tropica, also inhabits the shallow shelf where warm-water conditions prevail. Serolis tropica, a member of the North American ‘carinata’ group, is related to the ‘marplatensis’ group of South America. While it is argued that these two groups must have shared a common history, the remaining region of approximately 40° latitude between the northern and southern forms greatly complicates the relationship. Whether or not this gap is real or due to a lack of fine, inshore sampling can only be determined by further field work in this region. 相似文献
10.
分别将饱食后12h、24h、36h的水螅于胃腔中部横切:1)检查了下段横切面一定重量组织内有丝分裂处于中期的细胞数目;2)经12h、24h、36h修复后检查了上段一定重量愈合组织内有丝分裂处于中期的细胞数目.结果表明:1)水螅在饱食12h、24h、36h后,同一单位重量组织内有丝分裂处于中期的细胞数目以饱食24h时为最高;2)其创伤面经12h、24h、36h修复后,同一单位重量组织内有丝分裂处于中期的细胞数目以修复36h为最高;3)修复后愈合组织内有丝分裂处于中期的细胞数目均相应地高于横切后即时检查的数目. 相似文献