On the biology of female Epiplatys bifasciatus (Cyprinodontidae) from southern Sudan

The biology of female Epiplatys bifasciatus (Steindachner, 1881) from the Sudd region of southern Sudan was investigated. The population was dominated by females whose growth in body dimensions relative to total length was found to be linear. The reproductive system differs from that of oviparous teleosts in having a portion of the ovary (anterior) modified for carrying the developing brood. Gradual development of oocytes towards the nursing portion of the ovary, and low absolute fecundity of the brood, suggests a rather long breeding season (June to September).A large variety of food organisms belonging to three main groups, viz. insects, crustaceans and arachnids, were taken by Epiplatys collected from the littoral zones of two rivers, the Bahr El Ghazal and the White Nile. Little variation occurred in the food of these two populations. Chironomid larvae showed the highest occurrence frequency in the fish food for both localities, and insects in general constituted over 80% of all organisms eaten.     

Female Remating in Drosophila ananassae: Evidence for the Effect of Density on Female Remating Frequency

Drosophila ananassae, a cosmopolitan and domestic species, is largely circumtropical in distribution and belongs to the ananassae species complex of the ananassae subgroup of the melanogaster species group. In the present study, experiments were conducted to investigate the effect of density on female remating frequency by employing different wild-type and mutant strains of D. ananassae. Two experimental designs, i.e., 2-h daily observation and continuous confinement, were used. The results show that there is significant dependence of remating frequency on density in all strains tested under both experimental designs except in a wild-type strain (Bhutan), which shows no dependence of remating frequency on density under 2-h daily observation design. This finding provides evidence that density may increase the frequency of female remating in D. ananassae.     

A Comparative Analysis of Mating Recognition Signals in Graylings: Hipparchia statilinus vs. H. semele (Lepidoptera: Nymphalidae, Satyrinae)

Courtship is an important character linked to fitness and can evolve in response to female mate choice, to ensure sex identity and quality of a potential mate. It can also be a major pre-mating isolating mechanism in butterflies and many other species. In this paper, aspects of the reproductive behaviour of Hipparchia statilinus are described. First, the ethogram and the sequential structure of courtship leading to copulation and female refusal behaviour are showed; second, the results are compared with the behaviour of the sympatric and syntopic species, H. semele. Sequential analysis of H. statilinus courtship showed that, once a male has started the sequence, the following steps most likely follow up to the end. Courtship seems to reflect female behaviour: the male can repeat the whole sequence or part of it more than once, waiting for female signals. The general pattern of sexual behaviour in H. semele and in H. statilinus is mainly identical: perching strategy, flight pursuit, courtship. In both species, courtship consists of a highly stereotypic sequence, and differences between sequences are primarily related to presence/absence, order and performance of steps. This study is the first step of an experimental design addressed to a better understanding of mating recognition signals in Hipparchia and provides more details to define the relative roles of phylogeny and environment in shaping boundaries among species.     

Female wing spreading as acceptance signal in theDrosophila virilis group of species

Females of manyDrosophila species spread apart their wings prior to copulation. In the present study we found female wing spreading to provoke male copulation attempts inDrosophila virilis-group species, helping the males to attempt copulation when the female is ready to mate. The males of most species, however, rarely responded to female wing spreading by copulation attempt without licking the female genitalia before and/or after female wing spreading bout. Blocking the female genitalia (D. virilis, D. novamexicana) reduces males' tendency to attempt copulation after female wing spreading. In these, and most other species of the group, female wing spreading seems to be an efficient signal only when combined with stimuli from female genitalia.     

Antibacterial activity associated with Lactobacillus gasseri ATCC 9857from the human female genitourinary tract

The 10-fold concentrated spent MRS culture cell-free supernatant concentrate [(cCFS)] of the human female genitourinary tract isolate Lactobacillus gasseri ATCC 9857 was shown to exhibit antibacterial activity towards gram-positive sporogenous and asporogenous fermentative eubacteria in liquid and on solid media under conditions that eliminated the activity of lactic acid (-glycerophosphate) and hydrogen peroxide (catalase). The antibacterial activity of the cCFS was characterized by automated turbidometry (Bioscreen) and non-linear regression analysis (Gompertz model) using MRS broth cultures of the indicator strain L. acidophilus ATCC 11975. It exhibited a bactericidal mode of action, sensitivity to trypsin and proteinase K, partial sensitivity to pepsin and pronase E, partial heat stability at 121 °C for 15 min, and retained significantly more activity following exposure to pH 3.0 and 5.0 compared with pH 7.2 and 9.0. The inhibitory spectrum included a wide range of Lactobacillus species, Bifidobacterium bifidum, B. infantis and B. catenulatum, Lactococcus cremoris, Leuconostoc cremoris, Pediococcus pentosaceus, Bacillus cereus, Clostridium tyrobutyricum, C. pasteurianum, C. sporogenes, Staphylococcus carnosus, and Enterococcus faecalis. Although partial inhibition of Escherichia coli ATCC 25922 by cCFS was observed in liquid medium, inhibition of freshly isolated human uropathogenic E. coli strains could not be demonstrated on TSB agar plates by agar well diffusion. Following partial resolution by gel permeation FPLC on Superose-12, the fractionated cCFS was shown to comprise at least two inhibitory peptides (3.05 and 5.27 kDa) as well as aggregated inhibitory peptide material (21.65, 41.50, 81.20, and 120.90 kDa). The 3.05 kDa peptide, designated Gassericin D, inhibited L. acidophilus strains ATCC 11975 and ACA-DC 241. The 5.27 kDa peptide, designated Gassericin C, inhibited L. gasseri strain UCSC LF221Snb and En. faecalis DPC 3319. The aggregated 21.65 kDa peptide material strongly inhibited L. acidophilus ATCC 11975 and weakly inhibited Listeria inocua DPC 3306. The aggregated 41.50 kDa peptide material strongly inhibited Ba. cereus DPC 3316 and weakly inhibited L. acidophilus ACA-DC 241. The ability of L. gasseri ATCC 9857 to produce bacteriocin-like activity may be of importance in the biopreservation of nutraceuticals and in the management of female genitourinary and gastrointestinal tract infections involving En. faecalis.     

马哈利樱桃大孢子发生和雌配子体的发育

采用石蜡切片法对马哈利樱桃大孢子发生和雌配子体发育过程进行观察研究。结果表明:(1)马哈利樱桃雌配子体发育早期,在单室子房内可以看到2个倒生胚珠,但在后期其中一个退化,另一个发育为种子;其胚珠具双珠被,为厚珠心。(2)大孢子母细胞减数分裂形成直线型四分体,功能大孢子位于合点端;胚囊发育为蓼型,成熟胚囊为七细胞八核。(3)根据不同时间花的外部形态特征与内部解剖学对比的观察结果,在陕西关中地区,三月下旬是马哈利樱桃雌性生殖细胞分化和发育的重要时期,果园在此期间应加强肥水管理。     

Direct embryogenesis from female haploid protoplasts of Ginkgo biloba L., a medicinal woody species

Summary Haploid protoplasts isolated from prothallus (i.e. female gametophyte) of Ginkgo biloba, at densities ranging from 5×10⁴ to 10⁵ protoplasts per milliliter, were able to divide and form microclones which directly evolved into embryos, when they were cultured in two different liquid media. These were: the Murashige and Tucker medium (1969) modified by omitting ammonium ions and supplementing with glutamine, benzyladenine and various levels of naphthaleneacetic acid; or the Bourgin and Nitsch medium (1967) without growth regulators, supplemented with coconut milk. Three months later, the number of embryos ranged from 165 to 1900 embryos ml^–1 depending on the culture medium. After four months, embryos at whatever stage (globular, oblong or heart) exhibited a slow growth, which delayed the transfer onto solid media.Abbreviations BA 6-benzyladenine - BN Bourgin and Nitsch (1967) medium - MT Murashige and Tucker (1969) medium - NAA naphthaleneacetic acid     

Infant–Nonmother Interactions of Free-Ranging Mantled Howlers (Alouatta palliata) in Costa Rica

Proximate and ultimate explanations of interactions between infants and nonmothers vary depending upon the relatedness of the interactors. We investigated interactions of infants and nonmothers from a 22-month continuous study and from the long-term monitoring of the mantled howler population of La Pacifica, Guanacaste Province, Costa Rica. Relatedness is low or absent in these mantled howler groups. Juvenile females appeared to practice care skills with older infants, but as most first infants died, they failed to benefit. Infant positive interactions with adults occurred with the mother and probable father. Other adult females behaved aggressively toward the youngest infants. Mothers were retentive of infants and responded negatively to these interactions, suggesting that they perceived them as threatening. Interactions with infants appear to reflect competition in groups of unrelated adults. A review of other populations of Alouatta palliata and other species of howlers indicate variability in social group size and suggest variability in intragroup relatedness. We suggest that further study will confirm that social behavior (including interactions with infants) will vary by resource availability (group size) and associated demographic patterns (male and female migration) that affect relatedness in howler social groups.     

Male Sexual Signals and Female Choice in Drosophila grimshawi (Diptera: Drosophilidae)

Sexual selection and sexual signaling have been prominent topics in recent behavioral studies, but limited data have led to controversy regarding these topics. For example, the Hawaiian Drosophila are often cited as examples in which female choice has resulted in the evolution of elaborate male courtship signals, but relatively few data exist to test these claims adequately. We studied D. grimshawi, a lek-forming Hawaiian Drosophila, to determine whether there was evidence for female choice without male competition and to elucidate the possible cues females use to discriminate. Male mating success was found to be nonrandom and males that courted females intensely and deposited many pheromone-containing streaks on the substrate were the most successful. Hence, multiple cues seem to be involved in male mating success in this species. Some males performed only one display, however, and may represent an alternate male mating tactic. The protein content of the adult male diet significantly influenced the level of pheromone streak deposition, and thus, foraging environment may affect the outcome of sexual selection.     

Studies on the relationship between paracoccidioidomycosis in ddY mice and their estrous cycle

The relationship between paracoccidioidomycosis in ddY mouse and its estrous cycle was studied. Adult ddY mice of both sexes were used as experimental animals. Estrous cycle of female mice was examined before inoculation of Paracoccidioides brasiliensis yeast cells and mice were divided into 5 groups such as proestrus, estrus, metestrus-I, metestrus-II and diestrus. Each mouse was inoculated intravenously with 10⁶ P. brasiliensis yeast cell units and sacrificed on day 28 after inoculation. Their internal organs were cultured, and in addition, their histopathologies were studied. As a result, there was no difference in the organ cultures among the male and the female mice of 5 groups. However, histopathologically, the female groups at estrus, metestrus-I and metestrus-II were affected more severely than the male group, and the susceptibility of the female mice to the fungus was closely related to their estrous cycles.Abbreviations BHI-D brain heart infusion agar supplemented with 1.0% of anhydrous dextrose - PAS periodic acid-Schiff techniques - PBS phosphate buffered saline solution - SD standard deviation     

新小竹花形态结构及雌、雄配子体的发育研究

新小竹(Neomicrocalamus prainii)是一种小型攀援竹类,笋秆两用型竹种。该研究通过形态观察和石蜡切片的方法对新小竹花器官形态及解剖结构特征进行观察与描述,为研究竹类植物的生殖生物学提供新的理论信息。结果显示:(1)新小竹的花序为无限花序,没有小穗柄,成熟小穗平均长度为2.98 cm;每个小穗约有4～6朵小花,其中3～5朵为可育小花,顶端均有1朵不育小花;小穗基部有2～4个苞片;小穗轴每节长约0.52 cm。(2)新小竹的可育小花包括1片内稃、1片外稃、3枚浆片(浆片2大1小,边缘光滑)、6枚雄蕊和1枚雌蕊;雄蕊呈梭型,雌蕊羽毛状柱头三裂。(3)新小竹成熟花粉粒多为二核,具1个萌发孔;花药具有4个药室,花药壁由表皮、药室内壁、中层和绒毡层4层结构组成,绒毡层为腺质型;花药发育过程还存在多种异常情况。(4)新小竹子房一室,侧膜胎座,倒生胚珠,双珠被;大孢子母细胞由1个孢原细胞直接发育而成,合点端1个大孢子分化成为功能大孢子,由功能大孢子经过有丝分裂形成多核胚囊,直至发育成熟。研究表明,新小竹雄配子体存在发育异常现象,但大部分发育正常,其结实率低不仅与内在因素有关,外部环境也可能是导致其结实率低的重要因素。     

极危孑遗物种东方水韭雌配子体及胚胎的解剖学观察

以人工培养的国家一级保护植物东方水韭(Isoetes orientalis)为材料,采用切片技术对雌配子体和胚胎的发育进程进行解剖学观察研究,探讨其有性生殖过程及濒危机制。结果表明:(1)东方水韭大孢子3~5d萌发,成熟雌配子体呈球形,无假根,三裂缝处发育出多个颈卵器,成熟颈卵器只有颈壁细胞与颈沟细胞,无腹沟细胞。(2)多数雌配子体只发育出一个胚胎,偶见多胚共存现象;胚胎发育时期,第一叶原基相比第二、三叶原基发育迅速。(3)颈卵器部分组织常出现分化紊乱,导致雌配子体败育。该研究结果支持"根叶理论",并讨论了腹沟细胞的退化以及双胚共存机制,认为东方水韭雌配子体常停留在游离核阶段、颈卵器形态或位置不规则、卵细胞排列紊乱等可能是其败育的原因。     

The integration of an adult female gelada baboon (Theropithecus gelada)

An adult female gelada baboon has been integrated into an old-established group in the zoo in Rheine, West Germany. The integration took place in three steps: sight-contact, hourly meetings with the group, continuous stay in the group. Both the agonistic and the social-positive behaviour have been observed between the new female and the group-members. The integration was very difficult and lasted more than six months. The female was not really accepted, before she had not presented to the most dominant female of the one-male unit she has joined. This presenting only took place during the last part of the observations. In contrast to the adult female, the integration of juveniles occurred very quickly and nearly without any problems.     

A new species of Solanum subgen. Leptostemonum (Solanaceae) from Argentina

Solanum homalospermum (Solanum subgen.Leptostemonum) is described and illustrated from central Argentina.Solanum homalospermum is characterized by having heteromorphic gynoecia, strongly flattened seeds, unequal anthers, and gemmiferous roots.     

The influence of female age on phonotaxis during single and multiple song presentations in the field cricket,Gryllus integer (Orthoptera: Gryllidae)

The influence of age on variation in female phonontaxis in the field cricket,Gryllus integer, was investigated using a Kugel treadmill-type device. Synthetic male calling songs, with different pulse rates, were presented in both single-stimulus and three-stimulus designs. Females were either 11–14 or 25–28 days postecdysis. Females varied in motivation, or the degree of reproductive effort they exhibited, but only in single-stimulus trials: older females achieved higher scores than younger females. Females varied in selectivity, or the extent to which they discriminated among potential mates, in both presentation designs. All females discriminated against atypical pulse rates. In multiple-stimulus trials with normal range pulse rates, younger females were discriminatory; older females were not. Mated females showed reduced phonotaxis and selectivity irrespective of mating interval.     

Possible Female Choice During Copulation in Ozophora baranowskii (Heteroptera: Lygaeidae): Female Behavior, Multiple Copulations, and Sperm Transfer

The remarkable behavior of female Ozophora baranowskii of lightly tapping the male with the hind legs during copulation was studied in relation to multiple copulations, copulation length, and sperm transfer. Multiple copulations did not affect female fecundity, fertility, or longevity. The incidence of tapping was higher in shorter copulations, which did not result in sperm transfer to the female. Female tapping behavior may be a mechanism for choosing between males after copulation has begun.