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21.
于2007年4月至2009年3月间,在广东北江中上游地区采集间(鱼骨)(Hemibarbus medius)样本640尾,以鳞片作为年龄鉴定材料,对其种群的年龄与生长特征进行了研究.结果表明,间(鱼骨)鳞片上年轮结构清晰,前区主要表现为疏密型,而侧区主要为切割型;鳞片的边缘生长率表明,间(鱼骨)年轮的形成期主要为3~4月份.样本由0+~6+龄7个龄组组成,其中,雌性由1+~6+龄6个龄组组成,主要为1+~4+龄;而雄性由1+~5+龄5个龄组组成,主要为1+~3+龄;在4+ ~6+龄个体中,雌性78尾,雄性27尾,雌性显著多于雄性.体长(L,cm)与体重(W,g)的关系为W=0.011L3.149(♀)、W=0.011L3.135(♂),协方差分析表明,雌雄个体体长与体重关系的差异不显著,所有样本体长与体重的关系式为W=0.011L3.148.体长与鳞长(R,mm)呈幂函数及直线关系,关系式分别为L=6.387R0.853、L=4.569R+ 2.587.拟合的von Bertalanffy生长参数为L∞=29.855 0 cm,k=0.223 1,W∞=483.889 8 g,t0=-0.928 2龄.对理论体长与实测体长、理论体重与实测体重进行x2检验,两者的差异均不显著,表明von Bertalanffy生长方程能较好地拟合间(鱼骨)的生长.体重生长的拐点年龄为4.21龄,拐点体长约为20.37 cm,体重约为166.19 g.作为渔业保护对策,建议起捕年龄3龄以上或体长17 cm以上的个体.  相似文献   
22.
蓝昭军  范明君  黄小林  赵俊 《生态学报》2016,36(19):6091-6102
为了解中国南方唇鱼骨(Hermibarbus labeo)和间鱼骨(Hermibarbus medius)的种群分化、亲缘地理格局及物种有效性,作者对唇鱼骨8个水系及间鱼骨9个水系共148尾样本的Cyt b基因全序列进行了测定。在所有序列中,共有128个变异位点,共检测出了41个单倍型,单倍型多样性为0.954,核苷酸多样性为0.02153。基于Cyt b基因全序列构建的NJ树显示,中国南方的唇鱼骨与间鱼骨合聚为两大支,其中韩江和九龙江的全部唇鱼骨样本组成了Ⅰ支,而其他水系的唇鱼骨和间鱼骨样本则组成了Ⅱ支。两支系间的遗传距离为5.1%,而唇鱼骨和间鱼骨之间的遗传距离为3.2%。现有证据不支持间鱼骨与唇鱼骨达到种一级的分化。单倍型网络图显示,韩江、九龙江种群和其他水系的种群分化较大;海南岛三大水系种群和漠阳江种群的单倍型分支与代表珠江水系单倍型的分支之间的亲缘关系较近,与其他地理区间种群的亲缘关系则相对较远;西江可能为珠江水系、漠阳江水系和海南岛三大水系间鱼骨种群的扩散中心,其中一支往东向北江和东江扩散;另一支往南向海南岛扩散,海南岛三大水系种群尔后在冰期海退时向北扩散至漠阳江水系及珠江水系。AMOVA分析表明,唇鱼骨和间鱼骨地理区之间变异约占54.50%,地理区内种群间变异约占18.64%,种群内的变异占26.86%,这说明,唇鱼骨和间鱼骨种群Cyt b的遗传分化主要是来自地理区之间。错配分析及中性检验显示,全部种群、唇鱼骨种群、间鱼骨种群在历史上均没有发生过明显的扩张,两个mtDNA支系亦未发生过扩张,而海南岛的昌化江种群曾发生过种群扩张。  相似文献   
23.
There are 1 to 4 rows and five types of cortical alveoli in the cortex of the pallas (Hemibarbus labeo) egg.From the outer to the inner of the cortex,the diameter of the cortical alveoli decreases gradually.We found a new structure named solicitation speckle at the low latitude of the animal pole and near the micropylar apparatus between the ovum envelope and cell membrane in the zygote of fish.The solicitation speckle similar to type I cortical alveoli was very purple in H.E chromosome,and it had no obvious boundary with the ovum envelope and membrane.Moreover,no membrane around the solicitation speckle in TEM was found.In SEM,the solicitation speckle looked flocculent.During cortical reaction,the solicitation speckle played a very important function in arousing cortical reaction.Thirty-five seconds after fertilization,cortical alveoli began to break down near the low latitude of the animal pole.At the same time,the same thing happened near the micropylar apparatus before cortical reaction.Both starting points encountered and healed up at the vestibule of the micropylar apparatus.The cortical reaction that happened near the low latitude of the animal pole was another new pattern.The cortical reaction was divided into four parts that included latent period,developmental period,climactic period and declining period.In the latent period,no cortical alveoli were released.In the developmental period,a few cortical alveoli were released outside the cortex.In the climactic period,several cortical alveoli were inosculated into a big vesicle and released intensely.In the declining period,the type V cortical alveoli and the other remnant cortical alveoli were released.Five minutes after fertilization,cortical alveoli were released entirely in the animal pole.Five minutes after fertilization,all of the remnant cortical alveoli were released.This leads us to Conclude that cortical reaction is induced by type I cortical alveoli,and the solicitation speckle is a volcanic chain reaction under water or the other lower osmotic pressure of fluids.The outer cortical reaction can accelerate the inner cortical reaction.While cortical alveoli releases in batches,the cell plasma membrane is reorganized over and over.No cortical alveoli were found below the micropylar tube where sperm enters the ovum,which suggests that the cortical reaction prevents polyspermy.  相似文献   
24.
The fat-tailed dwarf lemur (Cheirogaleus medius; Cheirogaleidae) lives in the tropical forests of Madagascar. It is exceptional among primates, because this small nocturnal lemur hibernates during the dry season from the end of April until October. This field study was carried out to assess seasonal changes in body mass and behavioral traits (locomotor activity, feeding ecology) of C. medius that enable this species to accumulate large quantities of fat within weeks. Feeding observations of 36 radio-collared individuals were combined with a mark-recapture study in western Madagascar during the rainy seasons from 1995 to 1998. Pulp of fruit species not consumed, as well as fruit species eaten by C. medius was analyzed for lipid and sugar contents. Body mass changes of recaptured individuals revealed that C. medius may double its body mass within a few weeks. Most of the increase in body mass took place between March and April after infants had been weaned and directly before the onset of hibernation. Locomotor activity was significantly reduced during the period of body mass gain. During the entire study, fruits, nectar, and flowers of 34 different plant species comprised about 80% of the diet, supplemented by a seasonally varying intake of animal prey. Lipid contents of consumed fruits were comparatively low throughout the study period. No difference in lipid content was detectable between fruit species consumed and not consumed by C. medius. During prehibernation fattening, C. medius consumed mostly fruit species with a high sugar content, significantly higher than that of fruit species that were not consumed. The results suggest that a reduction in locomotor activity as well as a preference for fruit species with a high sugar content enable C. medius to deposit large quantities of fat in a few weeks. Received: 15 March 1999 / Accepted: 30 June 1999  相似文献   
25.
蓝昭军  林龙峰  赵俊 《生态学杂志》2017,28(4):1377-1386
唇鱼骨和间鱼骨均为分布较广的初级淡水鱼类,是理想的亲缘地理研究材料;且两者形态特征较为相似,不易鉴别,故两者的分布记述和物种有效性存在争议.为了解我国南部唇鱼骨和间鱼骨的群体遗传结构并探讨两者的物种有效性,本研究对8条水系的唇鱼骨和9条水系的间鱼骨共130尾个体的COIND5基因序列片段进行了测定,并对这两个基因的组合序列(2151 bp)进行了分析.结果表明: 在130尾个体的COIND5基因组合序列中,共有196个核苷酸变异位点,共检测出50个单倍型,单倍型多样性为0.964,核苷酸多样性为0.019,遗传多样性较高.基于COIND5基因组合序列构建的 NJ 树显示,所有种群可分为两支,支系Ⅰ包含了韩江和九龙江的全部单倍型以及瓯江的部分单倍型,余下的单倍型组成了支系Ⅱ.两支系间的遗传距离为0.036,而唇鱼骨与间鱼骨之间的遗传距离为0.027.单倍型网络图表明,韩江、九龙江种群和其他水系种群分化较大;漠阳江种群由海南岛种群扩散而来;海南岛各种群及漠阳江种群的单倍型分支与珠江水系单倍型的分支之间的亲缘关系较近,与长江水系单倍型分支之间的亲缘关系则较远;湘江、桂江和柳江之间的亲缘关系较近.AMOVA分析结果显示,地理区之间的变异约占71.2%,地理区内种群间变异约占16.6%,种群内的变异占12.2%,表明其遗传分化主要来自地理区之间.错配分析及中性检验结果显示,全部种群、唇鱼骨种群、间鱼骨种群、支系Ⅰ和支系Ⅱ在历史上均没有发生过明显的扩张.  相似文献   
26.
The purpose of this study was to establish the effects of different hip rotations during isometric side-lying hip abduction (SHA) in subjects with gluteus medius (Gmed) weakness by investigating the electromyographic (EMG) amplitude of the Gmed, tensor fasciae latae (TFL) activity, and gluteus maximus (Gmax), and the activity ratio of the Gmed/TFL, Gmax/TFL, and Gmed/Gmax. Nineteen subjects with Gmed weakness were recruited for this study. Subjects performed three isometric hip abductions: frontal SHA with neutral hips (SHA-N), frontal SHA with hip medial rotation (SHA-MR), and frontal SHA with hip lateral rotation (SHA-LR). Surface EMG amplitude was measured to collect the EMG data from the Gmed, TFL, and Gmax. A one-way repeated-measures analysis of variance was used to determine the statistical significance of the Gmed, TFL, and Gmax EMG activity and the Gmed/TFL, Gmax/TFL, and Gmed/Gmax EMG activity ratios. Gmed EMG activity was significantly greater in SHA-MR than in SHA-N. TFL EMG activity was significantly greater in SHA-LR than in SHA-N. The Gmed/TFL and Gmed/Gmax EMG activity ratios were also significantly greater in SHA-MR than in SHA-N or SHA-LR. The results of this study suggest that SHA-MR can be used as an effective method to increase Gmed activation and to decrease TFL activity during SHA exercises.  相似文献   
27.
There are 1 to 4 rows and five types of cortical alveoli in the cortex of the pallas (Hemibarbus labeo) egg. From the outer to the inner of the cortex, the diameter of the cortical alveoli decreases gradually. We found a new structure named solicitation speckle at the low latitude of the animal pole and near the micropylar apparatus between the ovum envelope and cell membrane in the zygote of fish. The solicitation speckle similar to type I cortical alveoli was very purple in H.E. chromosome, and it had no obvious boundary with the ovum envelope and membrane. Moreover, no membrane around the solicitation speckle in TEM was found. In SEM, the solicitation speckle looked flocculent. During cortical reaction, the solicitation speckle played a very important function in arousing cortical reaction. Thirty-five seconds after fertilization, cortical alveoli began to break down near the low latitude of the animal pole. At the same time, the same thing happened near the micropylar apparatus before cortical reaction. Both starting points encountered and healed up at the vestibule of the micropylar apparatus. The cortical reaction that happened near the low latitude of the animal pole was another new pattern. The cortical reaction was divided into four parts that included latent period, developmental period, climactic period and declining period. In the latent period, no cortical alveoli were released. In the developmental period, a few cortical alveoli were released outside the cortex. In the climactic period, several cortical alveoli were inosculated into a big vesicle and released intensely. In the declining period, the type V cortical alveoli and the other remnant cortical alveoli were released. Five minutes after fertilization, cortical alveoli were released entirely in the animal pole. Five minutes after fertilization, all of the remnant cortical alveoli were released. This leads us to conclude that cortical reaction is induced by type I cortical alveoli, and the solicitation speckle is a volcanic chain reaction under water or the other lower osmotic pressure of fluids. The outer cortical reaction can accelerate the inner cortical reaction. While cortical alveoli releases in batches, the cell plasma membrane is reorganized over and over. No cortical alveoli were found below the micropylar tube where sperm enters the ovum, which suggests that the cortical reaction prevents polyspermy. __________ Translated from Acta Hydrobiological Sinica, 2005, 29(5): 479–487 [译自: 水生生物学报, 2005, 29(5): 479–487]  相似文献   
28.
Korean barbel, Hemibarbus mylodon, is an endangered freshwater species endemic to Korea. In order to undertake a conservation program for this species in Korea, it is essential to evaluate its genetic diversity and population structure. For this purpose, we developed 10 polymorphic microsatellite markers and examined their allelic variation using a total of 60 wild individuals collected from three different localities. The number of alleles per locus ranged from three to 26. The expected and observed heterozygosities per locus ranged from 0.19 to 0.94 and from 0.20 to 0.98, respectively. Significant departures from Hardy–Weinberg equilibrium expectations occurred in four loci. These markers will be useful for the assessment of genetic diversity for this species.  相似文献   
29.
利用国内外通用的营养测试方法测定了花(Hemibarbus maculates)和唇(Hemibarbu labeo)的含肉率和肌肉营养成分。结果表明:花和唇含肉率分别是70.61%7、1.52%;花肌肉(鲜样)中蛋白质(18.41%)和脂肪含量(2.46%)显著高于唇的,而花的灰分含量要显著低于唇;水分含量分别是78.35%、78.51%,两者无显著差异。花和唇肌肉中脂肪酸种类丰富,饱和脂肪酸(SFA)4种,不饱和脂肪酸(UFA)7种;其中单不饱和脂肪酸(MUFA)4种,多不饱和脂肪酸(PUFA)3种;其中DHA含量高达5.00%和14.32%。花和唇肌肉中的氨基酸总量分别是63.07%和67.63%,呈味氨基酸分别为25.96%和26.30%。缬氨酸、蛋氨酸和胱氨酸为限制性氨基酸。  相似文献   
30.
There is a requirement in some beef markets to slaughter bulls at under 16 months of age. This requires high levels of concentrate feeding. Increasing the slaughter age of bulls to 19 months facilitates the inclusion of a grazing period, thereby decreasing the cost of production. Recent data indicate few quality differences in longissimus thoracis (LT) muscle from conventionally reared 16-month bulls and 19-month-old bulls that had a grazing period prior to finishing on concentrates. The aim of the present study was to expand this observation to additional commercially important muscles/cuts. The production systems selected were concentrates offered ad libitum and slaughter at under 16 months of age (16-C) or at 19 months of age (19-CC) to examine the effect of age per se, and the cheaper alternative for 19-month bulls described above (19-GC). The results indicate that muscles from 19-CC were more red, had more intramuscular fat and higher cook loss than those from 16-C. No differences in muscle objective texture or sensory texture and acceptability were found between treatments. The expected differences in composition and quality between the muscles were generally consistent across the production systems examined. Therefore, for the type of animal and range of ages investigated, the effect of the production system on LT quality was generally representative of the effect on the other muscles analysed. In addition, the data do not support the under 16- month age restriction, based on meat acceptability, in commercial suckler bull production.  相似文献   
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