Der Einfluß von Vitamin A und β-Carotin auf die Fruchtbarkeit bei suboptimalen und optimalen Vitamin-B-Gaben

Die vorliegenden Untersuchungen sind Bestandteil eines komplexen Forschungsprogramms zur Weiterentwicklung der energetischen Futterbewertung im Nettoenergie‐Fett‐System. Sie wurden mit dem Ziel durchgeführt, neue Ergebnisse zur Erfassung des Zusammenhanges zwischen Ort und Art der Nährstoffverdauung und der energetischen Verwertung von Rationen bei der Tierart Rind zu erarbeiten. Für 9 Rationsvarianten mit jeweils 3 Varianten der Stärkeherkunft (Gerste, Mais, Kartoffeln) und ihres Rationsanteiles (50, 25 und 10 %) wurde an weitgehend ausgewachsenen Ochsen mit Hilfe von duodenalen Brückenfisteln auf dem Ernährungsniveau 1.7 die ruminale Nährstoffverdaulichkeit gemessen. Bei Stärkeeinnahmen zwischen 484 und 2573 g je Tier und Tag wurden Mengen an ruminai und postruminal verdauter Stärke zwischen 444 und 2336 bzw. 10 und 284 g je Tier und Tag bestimmt. Für die organische Substanz, Stärke, wasserlöslichen Kohlenhydrate und N‐freien Reststoffe wurden hohe relative Anteile der ruminai verdauten an den scheinbar verdauten Nährstoffen mit Werten zwischen 78 und 88, 83 und 98, 93 und 97 bzw. 88 und 100% ermittelt.     

冬虫夏草菌丝状菌源增殖培养的研究

冬虫夏草菌是珍稀濒危名贵中药材冬虫夏草的无性型菌种,是侵染蝠蛾幼虫的唯一菌种,其侵染后形成名贵中药材冬虫夏草。冬虫夏草菌在不同营养及条件下生长形态不同,主要有丝状体和菌球体两种生长形态。冬虫夏草菌丝状菌体能够侵染蝠蛾幼虫,有可能作为一种新的接种体被广泛应用;但丝状菌体对营养要求苛刻、生长缓慢、菌丝体得率低的特点,阻碍了冬虫夏草菌丝状菌体作为侵染蝠蛾幼虫的接种体的开发及应用,从而阻碍了冬虫夏草人工培殖产业化的进程。为了提高冬虫夏草菌丝状菌体的生物表达量,本文对营养及培养条件进行了优化研究,得出了最佳条件为:葡萄糖质量浓度40 g/L、酵母粉质量浓度65 g/L、培养温度17℃、MgSO_4质量浓度3 g/L、KH_2PO_4质量浓度1.5 g/L、培养时间12 d,按最优培养条件,冬虫夏草菌丝状菌体干重得率15.67 g/L,为下一步新的接种体的制备提供菌源保障。     

外源激素对马尾松花芽分化及内源物质的影响

为探讨马尾松球花形成与植物激素水平的关系,该研究对贵州省都匀无性系种子园11年生马尾松进行不同浓度的 IAA、IBA、GA3、BAP等植物激素处理,采用考马斯亮蓝G-250染色法、蒽酮法分别对不同浓度不同激素处理后的枝条上针叶中的可溶性蛋白质和可溶性糖含量变化进行测定,并在第二年开花时对试验枝条的开花情况进行了调查。结果表明：在8－11月份,进行500 mg·L-1的BAP 处理有利于马尾松雌球花和雄球花的形成,100 mg·L-1的GA3处理有利于马尾松雌球花的形成;而GA3250 mg·L-1和GA3500 mg·L-1处理有利于马尾松雄球花的形成,IAA 250 mg·L-1对马尾松雌雄球花同枝的数量有提高作用。在10－11月份,对马尾松进行500 mg·L-1的BAP、IAA、GA3处理后,马尾松针叶内蛋白质含量变化有显著影响;在10月份时,进行BAP 100 mg·L-1处理后,其可溶性糖含量及可溶性蛋白含量均可达到极显著水平。而在8月份与10月份时,分别进行IBA 100 mg·L-1与IBA 250 mg·L-1处理后,其可溶性蛋白含量与其对照差异处于极显著水平;在11月份时,进行GA3100 mg·L-1处理后,其可溶性蛋白含量与其对照差异处于极显著水平;而在11月份时,进行IBA 500 mg·L-1处理后,其可溶性蛋白含量与对照差异处于显著水平。     

Early constraints in sexual dimorphism: survival benefits of feminized phenotypes

Sexual dimorphism (SD) has evolved in response to selection pressures that differ between sexes. Since such pressures change across an individual's life, SD may vary within age classes. Yet, little is known about how selection on early phenotypes may drive the final SD observed in adults. In many dimorphic species, juveniles resemble adult females rather than adult males, meaning that out of the selective pressures established by sexual selection feminized phenotypes may be adaptive. If true, fitness benefits of early female‐like phenotypes may constrain the expression of male phenotypes in adulthood. Using the common kestrel Falco tinnunculus as a study model, we evaluated the fitness advantages of expressing more feminized phenotypes at youth. Although more similar to adult females than to adult males, common kestrel fledglings are still sexually dimorphic in size and coloration. Integrating morphological and chromatic variables, we analysed the phenotypic divergence between sexes as a measure of how much each individual looks like the sex to which it belongs (phenotypic sexual resemblance, PSR). We then tested the fitness benefits associated with PSR by means of the probability of recruitment in the population. We found a significant interaction between PSR and sex, showing that in both sexes more feminized phenotypes recruited more into the population than less feminized phenotypes. Moreover, males showed lower PSR than females and a higher proportion of incorrect sex classifications. These findings suggest that the mechanisms in males devoted to resembling female phenotypes in youth, due to a trend to increase fitness through more feminized phenotypes, may provide a mechanism to constrain the SD in adulthood.     

One size fits all? Determinants of sperm transfer in a highly dimorphic orb‐web spider

The evolutionary significance of widespread hypo‐allometric scaling of genital traits in combination with rapid interspecific genital trait divergence has been of key interest to evolutionary biologists for many years and remains poorly understood. Here, we provide a detailed assessment of quantitative genital trait variation in males and females of the sexually highly dimorphic and cannibalistic orb‐weaving spider Argiope aurantia. We then test how this trait variation relates to sperm transfer success. In particular, we test specific predictions of the one‐size‐fits‐all and lock‐and‐key hypotheses for the evolution of genital characters. We use video‐taped staged matings in a controlled environment with subsequent morphological microdissections and sperm count analyses. We find little support for the prediction of the one‐size‐fits‐all hypothesis for the evolution of hypo‐allometric scaling of genital traits, namely that intermediate trait dimensions confer highest sperm transfer success. Likewise, our findings do not support the prediction of the lock‐and‐key hypothesis that a tight fit of male and female genital traits mediates highest sperm transfer success. We do, however, detect directional effects of a number of male and female genital characters on sperm transfer, suggesting that genital trait dimensions are commonly under selection in nature. Importantly, even though females are much larger than males, spermatheca size limits the number of sperm transferred, contradicting a previous hypothesis about the evolutionary consequences of genital size dimorphism in extremely size‐dimorphic taxa. We also find strong positive effects of male body size and copulation duration on the probability of sperm transfer and the number of sperm transferred, with implications for the evolution of extreme sexual size dimorphism and sexual cannibalism in orb weavers.     

Mate choice and the operational sex ratio: an experimental test with robotic crabs

The operational sex ratio (OSR: sexually active males: receptive females) predicts the intensity of competition for mates. It is less clear, however, under what circumstances, the OSR predicts the strength of sexual selection – that is, the extent to which variation in mating success is attributable to traits that increase the bearer's attractiveness and/or fighting ability. To establish causality, experiments that manipulate the OSR are required. Furthermore, if it is possible to control for any OSR‐dependent changes in the chosen sex (e.g. changes in male courtship), we can directly test whether the OSR affects the behaviour of the choosing sex (e.g. female choice decisions). We conducted female mate choice experiments in the field using robotic models of male fiddler crabs (Uca mjoebergi). We used a novel design with two females tested sequentially per trial. As in nature, the choice of the first female to mate therefore affected the mates available to the next female. In general, we detected significant sexual selection due to female choice for ‘males’ with larger claws. Importantly, the strength of sexual selection did not vary across five different OSR/density treatments. However, as the OSR decreased (hence the number of available males declined), females chose the ‘males’ with the largest claws available significantly more often than expected by chance. Possible reasons for this mismatch between the expected and observed effects of the OSR on the strength of sexual selection are discussed.     

Female behaviour and the interaction of male and female genital traits mediate sperm transfer during mating

Natural selection and post‐copulatory sexual selection, including sexual conflict, contribute to genital diversification. Fundamental first steps in understanding how these processes shape the evolution of specific genital traits are to determine their function experimentally and to understand the interactions between female and male genitalia during copulation. Our experimental manipulations of male and female genitalia in red‐sided garter snakes (Thamnophis sirtalis parietalis) reveal that copulation duration and copulatory plug deposition, as well as total and oviductal/vaginal sperm counts, are influenced by the interaction between male and female genital traits and female behaviour during copulation. By mating females with anesthetized cloacae to males with spine‐ablated hemipenes using a fully factorial design, we identified significant female–male copulatory trait interactions and found that females prevent sperm from entering their oviducts by contracting their vaginal pouch. Furthermore, these muscular contractions limit copulatory plug size, whereas the basal spine of the male hemipene aids in sperm and plug transfer. Our results are consistent with a role of sexual conflict in mating interactions and highlight the evolutionary importance of female resistance to reproductive outcomes.     

Magico‐spiritual power,female sexuality and ritual sex in Muslim Java: Unveiling the kesekten of magical women

This article argues that in practice, concepts of magico‐spiritual power (Javanese: kesekten; Indonesian: kesaktian) are linked with sexuality, particularly female sexuality, in some segments of contemporary Central and East Javanese Muslim society. Few scholars have turned attention to the interconnectedness of these seemingly contradictory topics. Feminist studies tend to focus on the ways in which women locate themselves within and critique Sharia‐based discursive and social orders, without considering the roles that magico‐spiritual power and associated practices play in these Islamic systems or in Islam in a more general sense. Similarly, male scholarship that considers the cultural relevance of Islam and magic rarely refers to gendered and sexual dimensions as praxis from a feminist perspective. By drawing on examples of ‘magical women’ including the Javanese spirit queen of the southern ocean Gusti Kanjeng Ratu Kidul, the historical Hindu figure Ken Dedes, and contemporary ritual sex practices at a Muslim saint's grave, we show how women, female spiritual beings and female sexuality, and sexuality in general, can be considered sources of magico‐spiritual power in Muslim Java. Our arguments conclude that in Javanese Islam, transgression of Sharia sexual norms can be both a sign and a source of magico‐spiritual power.     

Protective Cellular Mechanism of Estrogen Against Kidney Stone Formation: A Proteomics Approach and Functional Validation

Females have less incidence/prevalence of kidney stone disease than males. Estrogen thus may serve as the protective factor but with unclear mechanism. This study explores cellular mechanism underlying such stone preventive mechanism of estrogen. Madin darby canine kidney (MDCK) renal tubular cells are incubated with or without 20 nm 17β‐estradiol for 7 days. Comparative proteomics reveals 58 differentially expressed proteins in estrogen‐treated versus control cells that are successfully identified by nanoLC–ESI–Q‐TOF‐MS/MS. Interestingly, these altered proteins are involved mainly in “binding and receptor,” “metabolic process,” and “migration and healing” networks. Functional investigations demonstrate reduction of calcium oxalate (CaOx) crystal‐binding capability of the estrogen‐treated cells consistent with the decreased levels of annexin A1 and α‐enolase (the known CaOx crystal‐binding receptors) on the cell surface. High‐calcium and high‐oxalate challenge initially enhances surface expression of annexin A1 and α‐enolase, respectively, both of which return to their basal levels by estrogen. Additionally, estrogen reduces intracellular ATP level and promotes cell migration and tissue healing. Taken together, estrogen causes changes in cellular proteome of renal tubular cells that lead to decreased surface expression of CaOx crystal receptors, reduced intracellular metabolism, and enhanced cell proliferation and tissue healing, all of which may contribute, at least in part, to stone prevention.     

Male mate‐seeking and mating behaviors of Eucera nipponensis (Hymenoptera: Apidae) at a nectarless orchid habitat: Are empty flower patches a profitable rendezvous site?

Male solitary bees typically use emergence‐nesting areas and/or flower patches of food plants, where receptive females are relatively numerous, as rendezvous sites. However, mate‐seeking males have been also observed at food‐deceptive orchid patches, where numerous encounters with foraging females can hardly be expected, owing to the lack of floral rewards. Here, we describe the male mate‐seeking and mating behaviors of the Japanese long‐horned bee Eucera nipponensis at habitats of the food‐deceptive orchid Cymbidium goeringii. On the basis of the results, we report empty flower patches are not necessarily fruitless sites for mate‐seeking males because naive female bees, which are highly likely to be recently emerged and unmated, can be attracted to non‐rewarding orchids. We also suggest a possibility that a small number of the males could receive a “sexual reward” (i.e. mating opportunities), owing to the food‐deceptive orchid, in return for their pollination work. This occasional interaction could represent the initial stage in the evolution of sexually deceptive orchids from food‐deceptive orchids.