Journal of experimental zoology. Part A, Ecological genetics and physiology最新文献

Bi-directional actions of dehydroepiandrosterone and aggression in female Siberian hamsters. 脱氢表雄酮与雌性西伯利亚仓鼠攻击行为的双向作用。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2001

Nikki M. Rendon, G. Demas

There is a well-established positive relationship between gonadal steroids and aggression. In some seasonally breeding species, however, aggression often persists or is increased during short "winter-like" days when the gonads are regressed and circulating levels of gonadal steroids are relatively low. Although the mechanisms underlying short-day increases in aggression are not fully known, the adrenal androgen dehydroepiandrosterone (DHEA) has been suggested as an alternative neuroendocrine mechanism regulating seasonal aggression. We used two complementary experimental approaches to examine the bi-directional actions of DHEA and aggression in female Siberian hamsters, a seasonal rodent that displays increased aggression concomitant with elevated circulating DHEA in short days. In Experiment 1, we examined the effects of aggressive interactions on DHEA concentrations before and after an aggressive encounter in long- and short-day hamsters. Serum DHEA was altered in a photoperiod-dependent manner, with decreased DHEA levels in response to aggression in short- but not long-day hamsters. Next, we experimentally induced adrenal DHEA release via injections of exogenous ACTH and assessed changes in aggressive behavior across photoperiods. We show a robust increase in aggression in short compared with long days during baseline aggression trials; however, aggression was not significantly increased further in response to ACTH in either photoperiod during post-ACTH aggression trials. These findings suggest that DHEA plays a role in the regulation of short-day aggression, while also highlighting the need for additional studies addressing the causal relationship between DHEA and aggression in this and others species.

性腺类固醇与攻击性之间有明确的正相关关系。然而，在一些季节性繁殖的物种中，在性腺退化和性腺类固醇循环水平相对较低的短暂“冬季”日子里，攻击性往往持续存在或增加。虽然短时间内攻击性增加的机制尚不完全清楚，但肾上腺雄激素脱氢表雄酮(DHEA)已被认为是调节季节性攻击的另一种神经内分泌机制。我们使用了两种互补的实验方法来研究雌性西伯利亚仓鼠的DHEA和攻击性的双向作用，雌性西伯利亚仓鼠是一种季节性啮齿动物，在短时间内循环DHEA升高会增加攻击性。在实验1中，我们在长昼和短昼仓鼠中检测了攻击相互作用对攻击相遇前后DHEA浓度的影响。血清脱氢表雄酮(DHEA)以光周期依赖的方式改变，在短而非长日的仓鼠中，脱氢表雄酮(DHEA)水平在攻击反应中下降。接下来，我们通过注射外源性ACTH实验诱导肾上腺脱氢表雄酮释放，并评估整个光周期内攻击行为的变化。在基线攻击试验中，我们发现与长时间相比，短时间的攻击行为明显增加;然而，在ACTH后的攻击试验中，两种光周期对ACTH的反应并没有进一步显著增加攻击性。这些发现表明，脱氢表雄酮在短日攻击的调节中起作用，同时也强调需要进一步的研究来解决脱氢表雄酮和其他物种攻击之间的因果关系。

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引用次数: 17

Genetic variation in total number and locations of GnRH neurons identified using in situ hybridization in a wild-source population. GnRH神经元总数和位置的遗传变异利用原位杂交在野生源种群中鉴定。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2000

Katherine E. Kaugars, C. Rivers, M. Saha, P. Heideman

The evolution of brain function in the regulation of physiology may depend in part upon the numbers and locations of neurons. Wild populations of rodents contain natural genetic variation in the inhibition of reproduction by winter-like short photoperiod, and it has been hypothesized that this functional variation might be due in part to heritable variation in the numbers or location of gonadotropin releasing hormone (GnRH) neurons. A naturally variable wild-source population of white-footed mice was used to develop lines artificially selected for or against mature gonads in short, winter-like photoperiods. We compared a selection line that is reproductively inhibited in short photoperiod (Responsive) to a line that is weakly inhibited by short photoperiod (Nonresponsive) for differences in counts of neurons identified using in situ hybridization for GnRH mRNA. There was no effect of photoperiod, but there were 60% more GnRH neurons in total in the Nonresponsive selection line than the Responsive selection line. The lines differed specifically in numbers of GnRH neurons in more anterior regions, whereas numbers of GnRH neurons in posterior areas were not statistically different between lines. We compare these results to those of an earlier study that used immunohistochemical labeling for GnRH neurons. The results are consistent with the hypothesis that the selection lines and natural source population contain significant genetic variation in the number and location of GnRH neurons. The variation in GnRH neurons may contribute to functional variation in fertility that occurs in short photoperiods in the laboratory and in the wild source population in winter.

在生理调节中，脑功能的进化可能部分取决于神经元的数量和位置。野生啮齿动物种群在冬季样的短光周期对繁殖的抑制中含有天然的遗传变异，并且已经假设这种功能变异可能部分归因于促性腺激素释放激素(GnRH)神经元数量或位置的遗传变异。利用自然变化的野生白足鼠种群，在短的、类似冬季的光周期中，人工选择成熟性腺或反对成熟性腺的品系。我们比较了在短光周期(反应性)下繁殖抑制的选择系和在短光周期(无反应性)下弱抑制的选择系，以比较使用GnRH mRNA原位杂交鉴定的神经元计数的差异。光周期没有影响，但无反应选择系的GnRH神经元总数比有反应选择系多60%。不同系之间在更多前部区域的GnRH神经元数量有明显差异，而在后部区域的GnRH神经元数量没有统计学差异。我们将这些结果与早期使用GnRH神经元免疫组织化学标记的研究结果进行比较。结果与选择系和自然来源群体在GnRH神经元数量和位置上存在显著遗传变异的假设一致。GnRH神经元的变化可能导致实验室和野生源种群在冬季短光周期内的生育功能变化。

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引用次数: 2

Sponge cell reaggregation: Cellular structure and morphogenetic potencies of multicellular aggregates. 海绵细胞再聚集:多细胞聚集体的细胞结构和形态发生潜能。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2006

A. Lavrov, I. Kosevich

Sponges (phylum Porifera) are one of the most ancient extant multicellular animals and can provide valuable insights into origin and early evolution of Metazoa. High plasticity of cell differentiations and anatomical structure is characteristic feature of sponges. Present study deals with sponge cell reaggregation after dissociation as the most outstanding case of sponge plasticity. Dynamic of cell reaggregation and structure of multicellular aggregates of three demosponge species (Halichondria panicea (Pallas, 1766), Haliclona aquaeductus (Sсhmidt, 1862), and Halisarca dujardinii Johnston, 1842) were studied. Sponge tissue dissociation was performed mechanically. Resulting cell suspensions were cultured at 8-10°C for at least 5 days. Structure of multicellular aggregates was studied by light, transmission and scanning electron microscopy. Studied species share common stages of cell reaggregation-primary multicellular aggregates, early-stage primmorphs and primmorphs, but the rate of reaggregation varies considerably among species. Only cells of H. dujardinii are able to reconstruct functional and viable sponge after primmorphs formation. Sponge reconstruction in this species occurs due to active cell locomotion. Development of H. aquaeductus and H. panicea cells ceases at the stages of early primmorphs and primmorphs, respectively. Development of aggregates of these species is most likely arrested due to immobility of the majority of cells inside them. However, the inability of certain sponge species to reconstruct functional and viable individuals during cell reaggregation may be not a permanent species-specific characteristic, but depends on various factors, including the stage of the life cycle and experimental conditions.

海绵(门Porifera)是现存最古老的多细胞动物之一，可以为后生动物的起源和早期进化提供宝贵的见解。细胞分化和解剖结构的高度可塑性是海绵的特征。目前研究的海绵细胞解离后的再聚集是海绵可塑性的最突出的例子。本文研究了三种demosponge物种(Halichondria panicea (Pallas, 1766)、Haliclona aquaeductus (ssrhmidt, 1862)和Halisarca dujardinii Johnston, 1842)的细胞再聚集动态和多细胞聚集体结构。机械分离海绵组织。得到的细胞悬液在8-10℃下培养至少5天。用光镜、透射电镜和扫描电镜研究了多细胞聚集体的结构。所研究的物种具有相同的细胞再聚集阶段——初级多细胞聚集体、早期原始形态和原始形态，但物种之间的再聚集速度差异很大。在原始形态形成后，只有杜氏水蛭的细胞能够重建具有功能和活力的海绵。海绵重建在这个物种发生由于活跃的细胞运动。水蛭和水蛭细胞的发育分别在原始动物和原始动物的早期阶段停止。这些物种的聚集体的发育很可能由于它们内部的大多数细胞不动而被阻止。然而，某些海绵物种在细胞重组过程中无法重建功能和有活力的个体可能不是物种特有的永久特征，而是取决于各种因素，包括生命周期的阶段和实验条件。

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引用次数: 43

Performance of teeth of lingcod, Ophiodon elongatus, over ontogeny. 长形蛇鳕牙齿在个体发育中的表现。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 Epub Date: 2015-09-28 DOI: 10.1002/jez.1967

Katherine A Galloway, Philip S L Anderson, Cheryl D Wilga, Adam P Summers

Fish teeth can play several roles during feeding; capture, retention, and processing. In many fish lineages teeth may be present on non-jaw cranial bones that lack opposing teeth, such as the vomer and palatine. We hypothesized that teeth on different bones have different functions, and that the function of a set of teeth may vary over ontogeny. In this study, puncture, and draw performance of in situ vomerine teeth are compared to premaxillary teeth of the piscivorous lingcod, Ophiodon elongatus. The force required to pierce prey and to draw prey out of the mouth once the teeth were embedded was measured in ten individuals ranging from 205 to 836 mm SL to test for ontogenetic effects. Vomerine teeth in juvenile lingcod required proportionally less force to puncture prey items than adult lingcod, while premaxillary teeth showed the opposite trend. Draw force required to remove prey from the grasp of both toothed bones show the same shift with ontogeny. These results suggest that there is a shift in tooth function from vomerine to premaxillary teeth over ontogeny of lingcods. In juvenile lingcod, vomerine teeth function more effectively during initial puncture. In contrast, the premaxillary teeth pierce more effectively in adults. Juvenile lingcod are expected to use the premaxillary teeth while adult lingcod are expected to use the vomerine teeth to retain prey due to the larger force required for the prey to escape. The curvature of vomerine teeth increases over ontogeny suggesting increasing functional performance in retaining prey.

鱼的牙齿在进食过程中可以发挥多种作用;捕获、保留和处理。在许多鱼类谱系中，牙齿可能存在于没有相对牙齿的非颌颅骨上，如下颌和腭。我们假设不同骨骼上的牙齿具有不同的功能，并且一组牙齿的功能可能因个体发育而异。在这项研究中，刺穿和拉伸的原位vomerine牙齿的性能进行了比较，鱼食性lingcod，蛇齿鲨上颌前牙。在10个个体中测量了刺穿猎物和在牙齿嵌入后将猎物拉出口腔所需的力，其范围从205至836毫米SL，以测试个体发生效应。幼年陵鳕的下颌齿刺穿猎物所需的力量比成年陵鳕小，而前颌齿则相反。将猎物从两根齿骨的抓握中移走所需的拉力显示出个体发生时的相同变化。这些结果表明，在lingcods的个体发育过程中，牙齿功能从下颌到上颌前牙发生了转变。幼年伶鳕在初始穿刺时，牙的功能更有效。相比之下，上颌前牙在成人中穿洞更有效。幼年伶鳕会使用前颌牙，而成年伶鳕会使用后颌牙来留住猎物，因为猎物逃跑需要更大的力量。狼齿的弯曲度在个体发育过程中增加，表明在保留猎物方面的功能性能增加。

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引用次数: 15

Parasite infection negatively affects PHA-triggered inflammation in the subterranean rodent Ctenomys talarum. 在地下啮齿类动物中，寄生虫感染对pha引发的炎症有负面影响。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2003

J. Merlo, A. Cutrera, R. Zenuto

Magnitude and effectiveness of immune responses vary greatly between and within species. Among factors reported to determine this variation, parasitism is a critical one, although controversial effects of parasites over immunological indices have been reported. Information regarding immune strategies in species with different life histories is crucial to better understand the role of immune defenses in an ecological and evolutionary context. Here, we examine the influence of the parasite community on immune responsiveness of a solitary subterranean rodent, Ctenomys talarum. To do this, we assessed the impact of the natural parasite community and the experimental infection with Eimeria sp. on the phytohemagglutinin (PHA)-response, as well as other immune, condition, nutrition, and stress parameters. PHA-triggered inflammation was similarly impaired by Eimeria sp. infection alone or co-occurring with a number of gastrointestinal nematodes. None of the other physiological parameters studied were affected by parasitism. This indicates that parasitism is a general key factor modulating immune responsiveness of the host, and in particular for C. talarum, it could explain the great inter-individual variation previously observed in the PHA-response. Thus, our results highlight the importance of taking the parasite community into account in ecoimmunological studies, particularly when using immunological indices.

免疫反应的强度和效力在物种之间和物种内部差别很大。在已报道的决定这种变异的因素中，寄生是一个关键因素，尽管寄生虫对免疫指标的影响存在争议。关于不同生命史物种的免疫策略的信息对于更好地理解免疫防御在生态和进化背景下的作用至关重要。在这里，我们研究了寄生虫群落对独居地下啮齿动物Ctenomys talarum免疫反应的影响。为此，我们评估了天然寄生虫群落和艾美耳球虫实验感染对植物血凝素(PHA)反应的影响，以及其他免疫、条件、营养和应激参数。pha引发的炎症同样会因艾美耳球虫单独感染或与许多胃肠道线虫共同发生而受损。其他生理参数均不受寄生影响。这表明寄生是调节寄主免疫反应的一个普遍关键因素，特别是对于C. talarum，它可以解释之前在pha反应中观察到的巨大个体间差异。因此，我们的结果强调了在生态免疫学研究中考虑寄生虫群落的重要性，特别是在使用免疫学指标时。

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引用次数: 9

Morphological and ultrastructural study of the efferent ductules in the Chinese soft-shelled turtle Pelodiscus sinensis. 华鳖传出小管的形态学和超微结构研究。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2002

M. Waqas, Tengfei Liu, Ping Yang, N. Ahmed, Qian Zhang, Lisi Hu, C. Hong, Qiusheng Chen

Comparative study of the turtle excurrent duct system increases our understanding the evolution of sperm motility and fertility maintenance in higher vertebrates. Therefore, in this study we observed the histology and ultrastructure organization of efferent ductules in the Pelodiscus sinensis using light and transmission electron microscopy. The efferent ductules are extra- testicular and 22-28 in number originate from rete testis. The epithelium is entirely composed of two types of cells, the predominant non-ciliated and ciliated cells. The ciliated cells have long cilia that protrude into the lumen to form a meshwork. These cells associated with clusters of mitochondria in the supranuclear cytoplasm and possess coated vesicles, vacuole, intracellular spaces, and junction complexes. Ciliated cells in the proximal portion of the ductules contain an endocytic apparatus with coated pits and tubules in the apical cytoplasm. Interdigitations and lipid droplets are predominantly present around the nuclei of these cells. The non-ciliated cells have clusters of mitochondria present in both the supranuclear and perinuclear cytoplasm whereas, the nuclei of these cells are lightly stained. Moreover, the contour of the epithelium towards lumen is irregular as it has a deep indentation. The apical cytoplasm goes deep into the lumen to form cytoplasmic processes. This is the first study to describe the detailed features of efferent ductules in Pelodiscus sinensis with, special focus on the morphology of ciliated cells, as these cells are involved in the mixing of luminal fluid and transport of spermatozoa towards the distal region.

对龟排泄管系统的比较研究，增加了我们对高等脊椎动物精子运动和生育能力维持的进化的认识。因此，本研究采用光镜和透射电镜对中华佩罗铁花传出小管的组织学和超微结构组织进行了观察。传出小管位于睾丸外，22-28个起源于睾丸网。上皮完全由两种类型的细胞组成，主要是非纤毛细胞和纤毛细胞。纤毛细胞有长长的纤毛，伸入管腔形成网状结构。这些细胞与核上细胞质中的线粒体簇相关，具有包被的囊泡、液泡、细胞内空间和连接复合物。纤毛细胞在小管的近端部分包含一个内吞器，在顶端细胞质中有被包被的小坑和小管。这些细胞的细胞核周围主要有交叉结构和脂滴。非纤毛细胞在核上和核周细胞质中都有线粒体簇，而这些细胞的细胞核染色较浅。此外，上皮向管腔的轮廓不规则，有深凹痕。顶端细胞质深入管腔形成细胞质突起。这是第一个详细描述中国佩罗铁鱼传出小管特征的研究，特别关注纤毛细胞的形态，因为这些细胞参与了腔液的混合和精子向远端区域的运输。

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引用次数: 7

Overcrowding-mediated stress alters cell proliferation in key neuroendocrine areas during larval development in Rhinella arenarum. 过度拥挤介导的应激改变了砂鼻草幼虫发育过程中关键神经内分泌区域的细胞增殖。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-02-01 DOI: 10.1002/jez.2005

Mijal J Distler, L. Jungblut, N. Ceballos, D. Paz, A. Pozzi

Exposure to adverse environmental conditions can elicit a stress response, which results in an increase in endogenous corticosterone levels. In early life stages, it has been thoroughly demonstrated that amphibian larval growth and development is altered as a consequence of chronic stress by interfering with the metamorphic process, however, the underlying mechanisms involved have only been partially disentangled. We examined the effect of intraspecific competition on corticosterone levels during larval development of the toad Rhinella arenarum and its ultimate effects on cell proliferation in particular brain areas as well as the pituitary gland. While overcrowding altered the number of proliferating cells in the pituitary gland, hypothalamus, and third ventricle of the brain, no differences were observed in areas which are less associated with neuroendocrine processes, such as the first ventricle of the brain. Apoptosis was increased in hypothalamic regions but not in the pituitary. With regards to pituitary cell populations, thyrotrophs but not somatoatrophs and corticotrophs showed a decrease in the cell number in overcrowded larvae. Our study shows that alterations in growth and development, produced by stress, results from an imbalance in the neuroendocrine systems implicated in orchestrating the timing of metamorphosis.

暴露在不利的环境条件下会引起应激反应，从而导致内源性皮质酮水平的增加。在生命的早期阶段，已经有充分的证据表明，慢性应激通过干扰变质过程改变了两栖动物幼虫的生长和发育，然而，所涉及的潜在机制只被部分解开。我们研究了种在种内竞争对沙蟾蜍Rhinella arenarum幼虫发育过程中皮质酮水平的影响，以及它对特定脑区和脑垂体细胞增殖的最终影响。虽然过度拥挤改变了脑垂体、下丘脑和大脑第三脑室中增殖细胞的数量，但在与神经内分泌过程联系较少的区域，如大脑第一脑室，没有观察到差异。下丘脑细胞凋亡增加，垂体细胞凋亡未见增加。在过度拥挤的幼虫中，垂体细胞数量减少的是促甲状腺细胞，而不是生长萎缩细胞和促皮质细胞。我们的研究表明，由压力引起的生长和发育的改变，是由神经内分泌系统的不平衡引起的，而神经内分泌系统与变态时间的协调有关。

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引用次数: 4

How important is the eggshell as a source for initial acquisition of Salmonella in hatchling turtles? 蛋壳作为幼龟最初感染沙门氏菌的来源有多重要?

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2016-01-28 DOI: 10.1002/jez.2004

M. C. Holgersson, W. Nichols, R. Paitz, R. Bowden

How and when turtles first acquire gut microflora is largely speculative. In this study, the eggshell and hatching process were evaluated for their role in the initial acquisition of Salmonella, by red-eared slider turtles (Trachemys scripta elegans). First, we examined whether the eggshell is a viable substrate for bacterial persistence during incubation, and if internal egg components (i.e., albumen, yolk, and embryo) have detectable bacterial loads. Second, we experimentally manipulated Salmonella by treating eggs with combinations of Salmonella and gentamicin, an effective Gram-negative antibiotic. We found that the eggshell is a viable substrate for maintaining bacteria, as well as an effective barrier to Salmonella transmission as internal egg components were largely bacteria-free. Water samples collected 18 days post-hatch from individuals that were experimentally inoculated with a topical application of Salmonella as eggs had a higher prevalence of Salmonella than those from eggs inoculated with Salmonella but topically treated with gentamicin prior to hatching, control eggs, and eggs only treated with gentamicin, but by day 35 post-hatch there were no detectable differences among the treatment groups. Though it can also act as a barrier that prevents the bacteria from infecting the embryo prior to hatching these findings suggest that the eggshell is a likely source of Salmonella infection in turtle hatchlings.

海龟第一次获得肠道菌群的方式和时间很大程度上是推测性的。本研究对红耳滑龟(Trachemys scripta elegans)的蛋壳和孵化过程在沙门氏菌初始感染中的作用进行了评价。首先，我们检查了蛋壳是否是细菌在孵化期间持续存在的可行底物，以及鸡蛋内部成分(即蛋白、蛋黄和胚胎)是否具有可检测的细菌负荷。其次，我们通过实验，用沙门氏菌和庆大霉素(一种有效的革兰氏阴性抗生素)联合处理鸡蛋来控制沙门氏菌。我们发现蛋壳是维持细菌的可行底物，也是沙门氏菌传播的有效屏障，因为鸡蛋内部成分基本上是无细菌的。在孵卵后18天收集的水样中，实验接种沙门氏菌的个体的鸡蛋比接种沙门氏菌但在孵卵前局部使用庆大霉素的鸡蛋、对照鸡蛋和仅使用庆大霉素的鸡蛋的沙门氏菌患病率更高，但在孵卵后35天，处理组之间没有明显差异。虽然蛋壳也可以作为屏障，防止细菌在孵化前感染胚胎，但这些发现表明，蛋壳可能是海龟孵化中沙门氏菌感染的一个来源。

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引用次数: 6

Sperm storage and sperm competition across ovarian cycles in the dragon lizard, Ctenophorus fordi. 福特龙蜥(Ctenophorus fordi)卵巢周期中的精子储存和精子竞争。

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2013-08-01 Epub Date: 2013-06-06 DOI: 10.1002/jez.1803

Tobias Uller, Tonia Schwartz, Troy Koglin, Mats Olsson

Female sperm storage can influence male reproductive success and may favour males that produce sperm that remain viable across several ovarian cycles. Here we show that sperm are viable in the female reproductive tract across ovarian cycles in the mallee dragon, Ctenophorus fordi. Based on experimental mating trials, we show that stored sperm were generally less likely to fertilize eggs than recently inseminated sperm. The fertilization success of stored sperm increased with male body size relative to rivals. This may be due to differences in ejaculate volume or sperm number transferred by males of different sizes. However, there was no evidence that copulation time, which is correlated with ejaculate volume, contributed to fertilization success. We suggest that sperm storage across ovarian cycles may be common in small, multi-clutched lizards and that its impact on selection on male phenotypes could contribute to the evolution of lizard mating systems.

女性精子的储存可以影响男性的生殖成功，并可能有利于男性产生的精子在几个卵巢周期中保持活力。在这里，我们表明精子在雌性生殖道中存活在整个卵巢周期的mallee龙，Ctenophorus fordi。根据实验交配试验，我们表明，储存的精子通常比最近受精的精子更不可能使卵子受精。与竞争对手相比，储存精子的受精成功率随着雄性体型的增大而增加。这可能是由于不同大小的雄性在射精量或精子数量上的差异。然而，没有证据表明与射精量相关的交配时间对受精成功有影响。我们认为，精子在卵巢周期中的储存可能在小型、多卵蜥蜴中很常见，并且它对雄性表型选择的影响可能有助于蜥蜴交配系统的进化。

引用次数: 25

What do we (need to) know about the melatonin in crustaceans? 关于甲壳类动物的褪黑素，我们(需要)知道些什么?

IF 2.8 3区生物学 Q2 Agricultural and Biological Sciences

Journal of experimental zoology. Part A, Ecological genetics and physiology

Pub Date : 2013-08-01 Epub Date: 2013-05-06 DOI: 10.1002/jez.1800

S B Sainath, Ch Swetha, P Sreenivasula Reddy

Melatonin (N-acetyl-5-methoxy-tryptamine) was first discovered from the bovine pineal gland extract in 1958. Since then, its synthesis, metabolism, physiological, and patho-physiological functions are well studied in vertebrates; there is an increasing recognition of melatonin in invertebrates and especially in crustaceans. The presence of melatonin in crustaceans is now well documented and some functional aspects in the framework of crustacean biology have been demonstrated. This review aims at giving a comprehensive overview of the various physiological events regulated by this pleiotropic hormone. Topics include: glucose homeostasis, regulation of reproduction, molting, limb regeneration, and antioxidant properties. Finally, perspectives on current and possible research are offered.

褪黑素(n -乙酰-5-甲氧基-色胺)于1958年首次从牛松果体提取物中发现。从那时起，它的合成、代谢、生理和病理生理功能在脊椎动物中得到了很好的研究;在无脊椎动物，尤其是甲壳类动物中，人们对褪黑素的认识越来越高。褪黑素在甲壳类动物中的存在已经得到了很好的证明，并且在甲壳类动物生物学的框架中已经证明了褪黑素的一些功能方面。本文旨在对这种多效性激素调控的各种生理事件进行综述。主题包括:葡萄糖稳态、繁殖调节、蜕皮、肢体再生和抗氧化特性。最后，对当前和可能的研究进行了展望。

引用次数: 33