Reproductive Physiology of Fishes

Atlantic cod Gadus morhua larvae reached four‐fold (at low larval density) to 11 fold higher body mass (high larval density) at 50 days post hatch (dph) when fed zooplankton rather than enriched rotifers. A short period (22–36 dph) of dietary change affected larval growth positively if changed from enriched rotifers to natural zooplankton and negatively if prey type changed vice versa. Overall survival did not differ between the two larval groups at low larval density, but at high density the rotifer group had a higher overall survival (10·8% v. 8·9%). Long‐term growth was affected significantly by larval diet in favour of the zooplankton diet; juveniles reached a 23% higher mass in a 12 week growth period. No difference in growth performance was found between juveniles fed natural zooplankton during the larval period for 36, 22 or 14 days, but all these juveniles performed significantly better compared with the rotifer‐fed group. These findings suggest that optimal diet during a short period in the larval period can result in improved growth in both the larval and juvenile period. Improved rotifer quality may, therefore, hold a large potential for growth improvement in this species.     

血吸虫生殖生理的研究进展

血吸虫体外培养研究工作经过了半个世纪的努力,取得了很大的进展,其中较突出的有 Clegg[1]从童虫培养至成虫; Basch[2]使尾蚴人工转变童虫后继续体外培养达到童虫发育,雌雄合抱,雌虫产卵,但卵为异常卵.目前为止,无论在曼氏或日本血吸虫均在体外培养成功,但两种血吸虫所产的卵均为异常卵,而血吸虫的生殖生理研究是寻找血吸虫体外培养不育的关键.     

The Comparative Reproductive Physiology of Sea Turtles

Although the reproductive ecology of marine turtles has beenthe subject of numerous long-range studies, the reproductivephysiology of these unique animals is little known. Recently,however, preliminary anatomical and endocrinological studieshave provided a good basis on which to begin to attempt to explainseveral of their unusual biological systems. New findings relatedto the anatomy of Chelonia mydas and Lepidochelys olivacea arepresented. The female, although having a very massive pair ofsimultaneously functioning ovaries, appears in most ways verysimilar to other chelonians. Corpora hemorrhagica, corpora luteaand corpora atretica from active ovaries are briefly described.Ovulation coincides with a luteinizing hormone and progesteronesurge. Sperm are probably stored for the season after a singlemating period which appears to occur prior to the first ovulation.Males may also cycle and mating as well as nesting are seenas more or less seasonal. The seasonality could be controlledin part by melatonin or other endocrines from the sea turtle'smassive pineal complex. A hypothetical model for reproductionis presented in hopes of stimulating interest in physiologicalapproaches to the study of marine turtle reproduction.     

产后鳗鲡生殖生理学的研究

产卵后的鳗鲡（Ａｎｇｕｉｌｌａ ｊａｐｏｎｉｃａ）可分为顺产鳗鲡（Ｓｍｏｏｔｈｌｙ ｏｖｕｌａｔｅｄ ｅｅｌｓ,ＳＯＥ）和部分产鳗鲡（Ｐａｒｔｌｙ ｏｖｕｌａｔｅｄ ｅｅｌｓ,ＰＯＥ）两种类型,经组织学检查发现,ＳＯＥ性腺中第Ⅳ＾＋＋＋和第Ⅴ时相的卵细胞较多,而ＰＯＥ性腺中第Ⅳ＾＋＋和第Ⅵ时相的卵细胞较多。ＳＯＥ脑部的ｍＧｎＲＨ、血清ＧｔＨ和雌二醇（Ｅ２）的含量均显著高于ＰＯＥ,但ＳＯＥ脑部ｃＧｎＲＨ－Ⅱ及血清睾酮（Ｔ）含量与ＰＯＥ无显著差异。     

重庆地区雌性恒河猴生殖生理的季节性变化

目的 研究重庆地区雌性恒河猴性周期的行为、内生殖器随季节的变化.方法 36只人工饲养条件下的成年雌性恒河猴,①建立恒河猴个体月经史档案,观察不同生殖季节性周期的行为变化.②用彩色多普勒超声(CDFI)和MRI检测不同生殖季节恒河猴子宫形态、子宫内膜厚度在月经周期中的变化.③剖腹探查,直视下测量子宫各径线.结果 10月至次年2月恒河猴的月经周期短而规则,CDFI和MRI检测子宫内膜线清晰可见.3月至9月恒河猴的月经周期多不规则,CDFI和MRI检测子宫内膜线模糊,子宫内膜组织、卵巢组织随月经周期变化不明显.结论 重庆地区人工饲养条件下,雌性恒河猴的生殖季节为10月至次年2月,非生殖季节为3月至9月,其性周期的行为、内生殖器随季节变化明显.     

Widespread Presence of Human BOULE Homologs among Animals and Conservation of Their Ancient Reproductive Function

Sex-specific traits that lead to the production of dimorphic gametes, sperm in males and eggs in females, are fundamental for sexual reproduction and accordingly widespread among animals. Yet the sex-biased genes that underlie these sex-specific traits are under strong selective pressure, and as a result of adaptive evolution they often become divergent. Indeed out of hundreds of male or female fertility genes identified in diverse organisms, only a very small number of them are implicated specifically in reproduction in more than one lineage. Few genes have exhibited a sex-biased, reproductive-specific requirement beyond a given phylum, raising the question of whether any sex-specific gametogenesis factors could be conserved and whether gametogenesis might have evolved multiple times. Here we describe a metazoan origin of a conserved human reproductive protein, BOULE, and its prevalence from primitive basal metazoans to chordates. We found that BOULE homologs are present in the genomes of representative species of each of the major lineages of metazoans and exhibit reproductive-specific expression in all species examined, with a preponderance of male-biased expression. Examination of Boule evolution within insect and mammalian lineages revealed little evidence for accelerated evolution, unlike most reproductive genes. Instead, purifying selection was the major force behind Boule evolution. Furthermore, loss of function of mammalian Boule resulted in male-specific infertility and a global arrest of sperm development remarkably similar to the phenotype in an insect boule mutation. This work demonstrates the conservation of a reproductive protein throughout eumetazoa, its predominant testis-biased expression in diverse bilaterian species, and conservation of a male gametogenic requirement in mice. This shows an ancient gametogenesis requirement for Boule among Bilateria and supports a model of a common origin of spermatogenesis.     

Physiology of Rana pipiens Reproductive Behavior: A Proposed Mechanism for Inhibition of the Release Call

SYNOPSIS. Non-gravid femaleRana pipiens clasped by sexuallyactive males emit a release call and thereby signal their unreceptivestatus to the clasping male. The receptive condition of gravidfemales is indicated by absence, or inhibition, of the call.This paper provides evidence that arginine-8 vasotocin (AVT)can inhibit the release call by causing water uptake when afemale is in an aquatic environment, and suggests that watermight exert this effect by means of a mechanical distensionof the body wall or internal pressure. This paper also includesevidence that the ovaries are not necessary for AVT's inhibitionof the call. The literature dealing with the physiological basisof female frog reproductive behavior and the physiological basisof the release call are reviewed.     

单细胞动物和多细胞动物的激素印迹

激素印迹是单细胞动物和多细胞动物的一种生理现象,也是选择参与信号识别过程分子的工具。激素印迹后,受体记忆将遗传给子孙后代,因此其对进化的作用可能是很大的。同时,激素印迹还有利于物种的维持。另外,激素印迹过程还是具有终身效应的临时开放系统的一部分。没有印迹,就没有完全的受体成熟,而不成熟的受体是不能和适量的激素结合的。在围 期诸如治疗药物和环境污染剂等人工合成的物质分子易致错误或病理印迹。许多研究表明错误印迹对生物体具有重要的影响。当然,单细胞动物的激素印迹过程与多细胞动物并不完全一样。     

Physiology

Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of Webwatch focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here merely scratch the surface, but hopefully, point those requiring more information in the correct direction.