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Reproductive Biology (reproductive + biology)
Selected AbstractsReproductive Biology of Invertebrates, Volume XI: Progress in Asexual ReproductionETHOLOGY, Issue 12 2003Stephen M. Shuster No abstract is available for this article. [source] Reproductive Biology of the Epiphytic Bromeliad Werauhia gladioliflora in a Premontane Tropical ForestPLANT BIOLOGY, Issue 2 2005A. Cascante-Marín Abstract: The floral phenology, fruit and seed production, and self-compatibility of Werauhia gladioliflora, an epiphytic bromeliad with a wide distribution, were studied in a premontane forest in the Monteverde area in Costa Rica. The species presents the pollination syndrome of chiropterophily, and it is visited by the small bats Hylonycteris underwoodi and Glossophaga commissarisi (Glossophaginae). The population flowering period extended from October to early December (end of rainy season) and seed dispersal occurred from February to April (dry season). Most plants opened a single flower per night, either every day or at one-day intervals during the flowering period. In natural conditions, the average fruit set amounted to almost half of the potential output, but individual fecundity (number of seeds) remained high. Seed number per fruit and germination capacity after artificial selfing and out-crossing treatments did not differ from natural pollination conditions. Werauhia gladioliflora exhibited high levels of autonomous self-pollination and self-compatibility at the individual and population level, characters associated with the epiphytic habitat. These reproductive traits are also associated with early colonizer species, yet life history traits, such as seed dispersal, seedling establishment success, and growth, are likely to have a major role in determining the presence of this species in the successional vegetation patches scattered over the studied premontane area. [source] Effects of juvenile hormone I, precocene I and precocene II on the progeny of Microplitis rufiventris Kok. female when administered via its host, Spodoptera littoralis (Boisd.)JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2004W. E. Khafagi Abstract: Reproductive biologies of Microplitis rufiventris Kok. females resulting from topically treated Spodoptera littoralis (Boisd.) larvae with constant effective doses of juvenile hormone I (JHI, 1 ,g), precocene I (PI, 25 ,g) or PII (25 ,g) were investigated. Although the female wasps were treated during their presence as eggs or larvae in their hosts, the complete effects of the test compound were not apparent until the wasps had become adults. On the bases of the obtained results, the reproductive inhibition activity caused by the test compounds comprises of two categories: (1) reduction in progeny production, and (2) induction of significant proportion of imperfect ,non-functional' parasitoid progeny. Whereas, the adverse effect of JHI is only restricted to the second category, the adverse effects of PI or PII fall into both categories. Thus, workers should be aware of the delayed effects of new generations of pesticides which may occur in later stages of the non-target insects. [source] Reproductive biology of nonhuman primatesEVOLUTIONARY ANTHROPOLOGY, Issue S1 2002Article first published online: 7 JAN 200, Mike H. Jurke First page of article [source] Reproductive biology of the skate, Rioraja agassizii (Müller and Henle, 1841), off Puerto Quequén, ArgentinaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2009M. Estalles Summary A total of 230 specimens of the skate, Rioraja agassizii, was collected from the commercial bottom trawl fishery of Puerto Quequén, Argentina. During the warmer seasons greater proportions of females were sampled. The largest male and female sampled were 629 and 698 mm total length (TL), respectively. Sexual dimorphism was detected in the relationship between weight (W),TL and disc width (DW),TL, in that females were heavier and wider than males. The smallest mature male and female were 485 and 530 mm TL, respectively. TL at 50% maturity (TL50%) was estimated at 504 and 570 mm for males and females, respectively. Females exhibited heavier livers than males throughout their lifetimes. Seasonal variations in the gonadosomatic (GSI) and hepatosomatic (HSI) indices, and in the width of the left oviducal gland (OG), along with the greater number of pregnant females sampled during spring, suggested that the peak of the egg laying season could be during this season. The egg cases presented a mean length of 69.01 ± 5.53 mm, mean width of 43.40 ± 1.86 mm and mean weight of 17.00 ± 4.59 g. According to these results specimens from Puerto Quequén and southern Brazil appeared to differ in size, the peak of the egg-laying season and in egg dimensions. [source] Reproductive biology of Apareiodon affinis (Pisces: Parodontidae) in the Furnas Reservoir, Minas Gerais, BrazilJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2003T. Fonseca Ratton First page of article [source] Reproductive biology of the silver pomfret, Pampus argenteus (Euphrasen), in Kuwait watersJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2000S. Dadzie Summary The reproductive activities of the silver pomfret, Pampus argenteus (Euphrasen), in Kuwait waters were investigated from March 1996 to February 1998. Observations on the seasonal distribution of maturity stages and variations in seasonal fluctuations in the gonadosomatic index (GSI) confirmed recent findings that the spawning period begins in May. The species has a prolonged spawning period in the females extending from May to August, whereas the males mature in April and ripe specimens were encountered in monthly samples until September. The recruitment pattern confirmed the one breeding season. There are two spawning peaks, the first in May and the second in August. Variations in GSI relative to fish length indicated that females and males are most fecund at about 24.5,26.4 cm and 20.5,22.4 cm length classes, respectively. The males mature earlier than females, at a minimum size of 12.5,14.4 cm, while the females mature at 20.5,22.4 cm. The oocyte diameter-frequency distribution suggests a serial rhythm of spawning. Fecundity ranged from 28 965 to 455 661 and correlated positively with: (a) standard length (P < 0.006); (b) ovary weight (P < 0.001); and (c) body weight (P < 0.001), and negatively with egg size (P < 0.003). [source] Reproductive biology of the brown smoothhound shark Mustelus henlei, in the northern Gulf of California, MéxicoJOURNAL OF FISH BIOLOGY, Issue 4 2008J. C. Pérez-Jiménez Female brown smoothhound sharks Mustelus henlei were found to reproduce annually. A mature female carried both developing oocytes in the ovary and developing embryos in the uteri concurrently for c. 1 year. A great variability in the size of embryos was recorded each month, and the maximum embryo sizes were found from late January to mid-March. The largest oocytes in mature females were observed in mid-March. Gestation lasted c. 10 months. A linear relationship between maternal total length (LT) and the number of pups per litter (litter size one to 21) was estimated. Birth LT was reached in c. 280 mm. Females and males matured at 570,660 and 550,560 mm LT, respectively. Difference in the litter size among Californian coast (one to 10) and northern Gulf of California (one to 21) populations existed for this smoothhound shark. [source] Reproductive biology of two co-occurring mugilids, Liza argentea and Myxus elongatus, in south-eastern AustraliaJOURNAL OF FISH BIOLOGY, Issue 4 2008B. W. Kendall The reproductive biology of Liza argentea and Myxus elongatus occurring in two estuaries (Lake Macquarie and St Georges Basin) was found to differ. Gonado-somatic index values and macroscopic staging of gonads identified the peak spawning period of L. argentea occurred between March and November in Lake Macquarie and January and April in St Georges Basin. In contrast, peak spawning of M. elongatus was concentrated between January and March in both estuaries. Spawning of L. argentea probably occurred in the lower reaches of estuaries as well as in nearshore coastal waters, whereas evidence indicated M. elongatus spawned only in ocean waters. The mean fork length at maturity (LF50) was greater for females than males in both species, and it also occurred at a larger mean LF in M. elongatus (males = 230 mm and females = 255 mm) than L. argentea (males = 180 mm and females = 207 mm). Estimates of total potential fecundity were also greater for M. elongatus (425 484,1 157 029) compared to L. argentea (159 933,548 954). Both species had determinate fecundity and displayed a group synchronous pattern of oocyte development, with two distinct size classes of oocytes present in mature ovaries. Liza argentea probably release the larger class of oocytes in one spawning event, but this could not be established for M. elongatus. [source] Reproductive biology and population variables of the Brazilian sharpnose shark Rhizoprionodon lalandii (Müller & Henle, 1839) captured in coastal waters of south-eastern BrazilJOURNAL OF FISH BIOLOGY, Issue 3 2008A. C. Andrade Throughout 1 year, from October 2003 to September 2004, 88 visits to the landing site of a small urban fishery (APREBAN) in Rio de Janeiro city were conducted and 816 specimens of Rhizoprionodon lalandii were analysed. The sample, mostly females, was composed of two cohorts: young-of-the-year were abundant in spring and summer and adults predominated in autumn and winter. Gravid females were most abundant from April to June, whereas post-partum females composed most of the catch in August to September. Adult males were present all year although were more abundant between February and July. No neonates were captured during the study and most embryos collected measured slightly below the reported total length (LT) at time of birth (L0) for the species, suggesting that parturition may occur slightly outside the main fishing grounds or that neonates were not captured in commercial gillnets set at this time of the year. The mean LT at maturity (LT50) for males was 578 mm and females matured between 620 and 660 mm, although a precise estimate of LT50 for females could not be determined. The total length (LT) and total mass (MT) relationship was calculated for both sexes and showed no significant differences. The mean condition factor increased steadily from February to July followed by a steep decrease in values relative to females in August and September, suggesting a pupping season. The present study area can be classified as a coastal juvenile habitat and a probable mating ground for R. lalandii. [source] Reproductive biology of female big-bellied seahorsesJOURNAL OF FISH BIOLOGY, Issue 3 2004C. W. Poortenaar In this study, ovarian morphology, reproductive condition and sex steroid levels were investigated in the big-bellied seahorse Hippocampus abdominalis, collected by snorkel and SCUBA diving in Wellington Harbour, New Zealand. Within the ovary, oocytes were contained between an outer muscular wall and an inner layer of luminal epithelium. Two germinal ridges ran along the entire length of the ovary. In cross-section, oocytes were arranged in sequential order of development beginning at the germinal ridges and ending at the mature edge. Ovarian lamellae were absent. Vitellogenic and advanced cortical alveoli oocytes were elongated in shape, whereas maturing oocytes were distinctively pear-shaped. Mature oocytes were large (2·6 , 4·4 mm in length) and aligned with the animal pole towards the muscular wall. Reproductively mature females were found throughout the year indicating a protracted reproductive season. The gonado-somatic index was significantly different between all ovarian stages, but the hepato-somatic index was not. Females with previtellogenic ovaries had significantly higher plasma concentrations of testosterone than females with vitellogenic or maturing ovaries. There was no significant difference in plasma concentrations of testosterone between females with vitellogenic or maturing ovaries, or in plasma concentrations of 17,-oestradiol between females in all ovarian stages. This study contributes to the knowledge on the reproductive biology of female syngnathids. [source] Reproductive biology of the onychophoran Euperipatoides rowelliJOURNAL OF ZOOLOGY, Issue 4 2000Paul Sunnucks Abstract The reproductive biology of the ovoviviparous peripatus Euperipatoides rowelli was investigated from field collections and laboratory cultures. The sexes have different demographics. The frequency distribution of individual weight is essentially L-shaped in females, but closer to normality for males: thus the sexes must exhibit different patterns of growth and/or mortality. Males are generally much smaller and rarer than females. The primary sex ratio seems to be 1:1 with equal investment in the sexes, while the tertiary ratio is highly female-biased. Logs with fewer individuals tend to be male-biased while well-populated logs tend to be female-biased. Males mature at 15,30% of the bodyweight of mature females. The weight frequency distribution of males without developed sperm in their tracts is strongly skewed to the lower weights, while that of males with sperm is more normally distributed, indicating that sperm production occurs as soon in life as possible. Males mature in their first year of life, if growth rates in culture may be extrapolated to the wild. In contrast to this rapid maturity in males, females may mature as late as their second or third years. Most mature females, and many prior to maturity, carry sperm in their spermathecae. After maturity, there is an approximately linear relationship between body mass and number of developing embryos. Reproduction in E. rowelli is significantly seasonal despite high individual variance, with a major bout of parturition in November,December (summer). A female can harbour one developed and one undeveloped batch of embryos in each uterus. Excesses of developed embryos in one uterus are counterbalanced by deficits of undeveloped ones, indicating that females can use their paired reproductive tracts independently. Individual females in culture can experience episodes of parturition approx. 6 months apart without re-mating, thus gestation may be 6 months or more. Sperm in spermathecae remain capable of vigorous swimming for at least 9.5 months. [source] Reproductive biology and pollination ecology of the rare Yellowstone Park endemic Abronia ammophila (Nyctaginaceae)PLANT SPECIES BIOLOGY, Issue 2 2006N. ELIZABETH SAUNDERS Abstract We examined the breeding system, reproductive output and pollination ecology of Abronia ammophila Greene, a rare and highly restricted endemic of Yellowstone National Park, Wyoming, USA. Floral morphology permits the automatic deposition of self-pollen on the stigma of individual flowers, and male and female reproductive functions temporally overlap. In controlled hand-pollination treatments, we found no significant difference among pollination treatments (unmanipulated, self-pollinated or cross-pollination). The species maintains a long reproductive season with high reproductive output (natural seed set ranged from 59 to 84%). Our results, along with pollinator observations, suggest that A. ammophila exhibits a mixed-mating system: the species can produce seed without pollinators (via either autogamy or agamospermy), but is also visited by an array of pollinating insects that included moths, butterflies and bumblebees. However, noctuid moths were the most abundant pollinators. In contrast, other Abronia species are obligate outcrossers. The mixed-mating system of A. ammophila may have evolved as a consequence of ecological pressures such as scarcity of mates or pollinators. [source] Reproductive biology of two Cattleya (Orchidaceae) species endemic to north-eastern BrazilPLANT SPECIES BIOLOGY, Issue 2 2006ERIC CAMARGO SMIDT Abstract The reproductive biology of the endemic Cattleya elongata and the endemic and critically endangered Cattleya tenuis (Orchidaceae) was studied in areas of ,campo rupestre' and ,caatinga' vegetation, respectively, in the Chapada Diamantina, north-eastern Brazil. Floral visitors and their behavior were recorded, and experimental pollinations were carried out to determine the breeding systems of these species. The species have similar flower morphology, flower in synchrony and both are pollinated by queens of Bombus (Fervidobombus) brevivillus (Apidae, Bombina). Flowers of both species do not present nectar despite the presence of a nectary-like cuniculus. Cattleya tenuis presented low natural fruit set (10%), while C. elongata presented a higher fruit set (25%). Both species are self-compatible, and only C. tenuis presented inbreeding depression, expressed as reduced seed viability in self-pollinations compared with cross-pollinations. The species have a parapatric distribution and differences in their habitats probably act as the principal barriers to the formation of natural hybrids. [source] Reproductive biology of pink dentex Dentex gibbosus (Rafinesque) from the Adriatic Sea, CroatiaAQUACULTURE RESEARCH, Issue 9 2007Leon Grubisic Abstract A 4-year study (May 1997,December 2000) of the reproductive biology of pink dentex Dentex gibbosus (Rafinesque) from the Adriatic Sea revealed that this species is a rudimentary hermaphrodite. The smallest mature males and females captured were 38.70 cm in total length (TL) and 39.80 cm in total length (TL) respectively. The von Bertalanffy growth parameters estimated for the entire population were: L,=107.24, K=0.12 and t0=,0.90. Fifty per cent of the population were sexually mature at 41.50 cm TL, while 100% of the specimens were sexually mature at 57.00 cm TL. Both monthly gonadosomatic index and macroscopically determined gonad stages strongly indicate that the pink dentex from the Adriatic Sea spawn partially in August, September and October. The mean value of absolute fecundity (F) was 1672 × 106 eggs. The results of great fertility of the pink dentex, partial spawning and relatively late sexual maturation suggest that the pink dentex has a high potential for commercial culture. [source] Reproductive biology of Boswellia serrata, the source of salai guggul, an important gum-resinBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2005V. G. SUNNICHAN Detailed studies were carried out on the phenology, floral biology, pollination ecology and breeding system of Boswellia serrata Roxb. (Burseraceae) the source of ,salai guggul'. The trees remain leafless during the entire period of flowering and fruiting. The inflorescence is a terminal raceme and produces up to 90 bisexual, actinomorphic flowers. On average a flower produces 10 044 ± 1259 starch-filled pollen grains. About 85% of the fresh pollen grains are viable; the pollen to ovule ratio is 3348 : 1. The stigma is of the wet papillate type. The style is hollow with three flattened stylar canals filled with a secretion product. The stylar canals are bordered by a layer of glandular canal cells. The inner tangential wall of the canal cells shows cellulose thickenings. The ovary is trilocular and bears three ovules, one in each locule. Flowers offer nectar and pollen as rewards to floral visitors. The giant Asian honey bee (Apis dorsata) and A. cerana var. indica(Indian honey bee) are the effective pollinators. The species is self-incompatible and the selfed pollen tubes are inhibited soon after their entry into the stigma. Self-pollen tubes develop a characteristic ,isthmus' as a result of enlargement of the tube soon after emergence through the narrow germ pore. Cross-pollinated flowers allowed normal pollen germination and pollen tube growth, and resulted in fruit- and seed-set. Under open pollination fruit-set was only about 10%. Although manual cross-pollinations increased fruit set, it was only up to about 20%. Low fruit set appears to be the result of inadequate cross-pollination and other constraints, presumably limitation of available nutrients. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 147, 73,82. [source] Reproductive biology of a mycoheterotrophic species, Burmannia wallichii (Burmanniaceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2000DIANXIANG ZHANG The breeding system of a mycoheterotrophic species, Bumannia wallichii (Miers) Hook. f. (Burmanniaceae), is assessed using field observations, floral anatomy, pollen histochemistry and isozyme electrophoresis. The structure of the flower effectively prevents pollinators from accessing the stamens, and no pollinators were observed visiting natural populations in Hong Kong. The pollen is starch-rich but lipid-poor. Analysis of isozyme variation revealed a small proportion of polymorphic loci, a low level of total heterozygosity (HT= 0.1972), and a very high overall fixation index of populations (FIT= 0.6602). These results strongly suggest that B. wallichii is predominantly self-pollinated. The coefficient of gene differentiation (GST) is low (0.05), although it is suggested that this is due to genetic homogenization of populations consonant with the formation of numerous tiny ,diaspora' seeds that are wind dispersed. [source] Breeding biologies, seed production and species-rich bee guilds of Cleome lutea and Cleome serrulata (Cleomaceae)PLANT SPECIES BIOLOGY, Issue 3 2008JAMES H. CANE Abstract The summer-blooming annual forbs Cleome lutea and Cleome serrulata (Cleomaceae) are native across the US Intermountain West and Rocky Mountains, respectively. Their farmed seed is sought to help rehabilitate western rangelands in those regions. This study of the reproductive biologies and pollinator faunas of C. lutea and C. serrulata is the first for this cosmopolitan family, the sister family to the Brassicaceae. Unlike the S-allele self-incompatibility systems of some Brassicaceae, both species of Cleome were found to be self-fertile and capable of some autogamy. Compared with selfing, outcrossing did not enhance seed set, seed viability or seedling vigor for either species (in fact, selfed progeny were more robust). Large, openly visited plants yielded >20 000 seeds each. Like several species of the sister family Capparaceae, flowers of both species first shed their pollen, secreted nectar and became receptive nocturnally. Although no nocturnal visitors were found, both Cleome species attracted a diverse array of diurnal native bees, wasps and butterflies. Among the many floral generalist bees that work Cleome flowers for pollen and nectar are two managed agricultural pollinators, Apis mellifera and Megachile rotundata. These observations bode well for pollinating C. lutea and C. serrulata in small commercial seed fields. It appears that diverse wild bees would benefit from the addition of native Cleome to restoration seed mixes, with the objective of sustaining native pollinator faunas during the first few years of postfire plant community rehabilitation. [source] Shade-Coffee Plantations as Refuges for Tropical Wild Orchids in Central Veracruz, MexicoCONSERVATION BIOLOGY, Issue 3 2005LISLIE SOLIS-MONTERO biología reproductiva; epifitas vasculares; estratificación vertical; estructura poblacional; limitación de polinizador Abstract:,In central Veracruz, Mexico, coffee plantations have replaced large areas of lower montane cloud forest. Shade-coffee plantations with high levels of structural diversity provide refuge for forest-dependent biota (e.g., birds and insects). Orchids typical of natural forest may also be found in the canopy of shade-coffee agroecosystems. It is not known, however, whether these are relicts from the original forest vegetation or if the plantations themselves provide the necessary conditions to support a self-sustained orchid population. We studied the population structure of the epiphytic orchids Jacquiniella teretifolia (Sw.) Britton & Willson, Scaphyglottis livida (Lindl.) Schltr., and Maxillaria densa Lindl. in a shade-coffee plantation (commercial polyculture) in central Veracruz. We also studied the previously undescribed reproductive biology of the latter two species. Our results show that the three orchid species had high population densities (>800 plants/ha). In our study site, 50% to 68% of the orchid plants of the target species were young individuals (less than five shoots). Reproductive structures were present in 80% of individuals larger than 30 shoots in the three species. M. densa is self-incompatible, and the fruit set obtained from cross pollination (42.7%) was higher than that obtained from natural pollination (18.2%), suggesting that this species could be pollinator limited. S. livida is autocompatible, not autogamous, and was not pollinator limited. Our results show that the coffee plantation had abundant orchid populations with log-normal size/age structures. Two of the target species, M. densa and S. livida, depend on pollinators to reproduce. It is clear that pollinators that allow orchids to set a high proportion of fruits persist in shade-coffee plantations. Coffee plantations may not replace the original conditions of a forest, but it is possible that these and other orchid species survive and reproduce in coffee plantations that provide appropriate microclimate conditions for the plants, including pollinators. Resumen:,En el centro de Veracruz, México, las plantaciones de café han reemplazado a extensas áreas de bosque nublado montano. Las plantaciones cafetaleras de sombra con altos niveles de diversidad estructural proporcionan refugio a biota dependiente de bosques (e. g., aves e insectos). En el dosel de agroecosistemas de café de sombra también se pueden encontrar orquídeas típicas de bosques naturales. Sin embargo, no se conoce si son relictos de la vegetación del bosque original o si las plantaciones mismas proporcionan los recursos necesarios para soportar a una población de orquídeas auto sostenida. Estudiamos la estructura de la población de orquídeas epifitas Jacquiniella teretifolia (Sw.) Britton & Willson, Scaphyglottis livida (Lindl.) Schltr y Maxillaria densa Lindl en una plantación de café de sombra (policultivo comercial) en el centro de Veracruz. También estudiamos la biología reproductiva, no descrita previamente, de las últimas dos especies. Nuestros resultados muestran que las tres especies de orquídea tuvieron densidades poblacionales altas (>800 plantas/ha). En nuestro sitio de estudio, entre 50% y 68% de las plantas de las especies estudiadas eran individuos jóvenes (menos de cinco rebrotes). En las tres especies hubo presencia de estructuras reproductivas en 80% de los individuos con más de 30 rebrotes. M. densa es auto incompatible, y el conjunto de frutos obtenido por polinización cruzada (42.7%) fue mayor que el obtenido por polinización natural (18.2%), lo que sugiere que esta especie puede estar limitada por polinizadores. S. livida es autocompatible no autogama, y no fue limitada por polinizadores. Nuestros resultados muestran que la plantación de café tenía poblaciones de orquídeas abundantes con estructuras tamaño/edad log normales. Dos de las especies, M. densa y S. livida, dependen de polinizadores para su reproducción. Es claro que los polinizadores que permiten una alta proporción de frutos a las orquídeas persisten en las plantaciones. Puede que las plantaciones de café no sustituyan las condiciones originales de un bosque, pero es posible que estas, y otras, especies de orquídeas sobrevivan y se reproduzcan en plantaciones de café que proporcionen condiciones microclimáticas adecuadas, incluyendo polinizadores, para las plantas. [source] The sublethal effects of tebufenozide on the precopulatory and copulatory activities of Choristoneura fumiferana and C. rosaceanaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2004Renée Dallaire Abstract The sublethal effects of tebufenozide, an ecdysone agonist, on the reproductive biology of Choristoneura fumiferana (Clem) and of Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), treated during the larval stage, were evaluated using two treatment methods: the force-feeding method and the diet method. The percentage of mortality and the developmental time of survivors increased linearly with the concentration of tebufenozide used. This ecdysone analogue proved to be more toxic to C. fumiferana than to C. rosaceana. In C. rosaceana, the weight of males and females decreased proportionally with the dose ingested, but females were affected to a greater extent. This difference might be due to a greater consumption of the treated diet, or to a differential vulnerability to tebufenozide. Tebufenozide did not modify the pre-copulatory activities associated with chemical communication in the females. However, the consumption of tebufenozide delayed ovarian maturation, causing a reduction in the fecundity of females. Treated males had smaller spermatophores and fewer eupyrene sperms in their bursa copulatrix and spermatheca, along with lower mating success. In C. fumiferana, tebufenozide delayed the females' onset time of calling the first night after emergence, but did not affect the mean time spent calling or the production of the main component of the sex pheromone. The males showed significantly greater difficulty in executing oriented flight in a wind tunnel, although their mating success was not affected. We concluded that tebufenozide interferes with various aspects of the reproductive biology of males and females of C. fumiferana and C. rosaceana, including some pre-copulatory behaviors associated with sex pheromone communication. [source] Factors affecting the reproductive biology of Melittobia digitata and failure to meet the sex ratio predictions of Hamilton's local mate competition theoryENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2003M.F. Cooperband Abstract Melittobia digitata Dahms (Eulophidae, Tetrastichini), a species of parasitic wasp satisfying all of Hamilton's local mate competition requisites, does not exhibit the predicted change in sex ratio with increased foundress number. A multifactorial design was used to test how age, oviposition experience, feeding experience, mating, and foundress number affect host-acceptance, number of offspring, and sex ratio of this species developing on honey bee pupae, Apis mellifera (L.) (Apidae, Apini). All factors significantly affected the time it took for oviposition to commence. Females oviposited soonest when they were 2 days old, mated, had previous feeding and oviposition experience, and were placed on hosts with multiple foundresses. Although the age difference between 2- and 5-day-old females is small, it significantly affected reproductive behavior. Age, mating, and foundress number were found to have an effect on sex ratio, however, the foundress effect was found to be a mathematical artifact of the limited host size. After correcting for this variable, females were found to have a constant sex ratio of approximately 0.05. Several 2-way interactions between factors were revealed: age and experience, age and foundress number, age and mating, foundress number and experience, and foundress number and mating. One 3-way interaction was found between age, mating, and foundress number. This study demonstrates that the sex ratio of M. digitata is not altered with increased foundresses, as predicted by Hamilton, and that slight changes in preconditioning may modify reproductive behavior. [source] Female reproductive biology of Platygaster diplosisae (Hymenoptera: Platygastridae) and Aprostocetus procerae (Hymenoptera: Eulophidae), two parasitoids associated with the African Rice Gall Midge, Orseolia oryzivora (Diptera: Cecidomyiidae)ENTOMOLOGICAL SCIENCE, Issue 2 2008Souleymane NACRO Abstract We investigated the female reproductive system of Platygaster diplosisae (Hymenoptera: Platygastridae) and Aprostocetus procerae (= Tetrastichus pachydiplosisae) (Hymenoptera: Eulophidae), two parasitoids associated with the African rice gall midge, Orseolia oryzivora (Diptera: Cecidomyiidae). Both optical and electron microscopy were used. The female reproductive system of P. diplosisae includes two large ovaries of the meristic polytrophic-type, each composed of several tens of ovarioles. The system includes also a venomous gland that extends to a common oviduct. This gland had a filiform secretory portion, in which the epithelium was thin and surrounded a common evacuation canal. The secretory cells secrete into a large reservoir. Parasitism due to P. diplosisae is gregarious. The female reproductive system of A. procerae includes two ovaries of the meristic polytrophic-type, and each ovary has a few ovarioles. Each ovariole includes one or two oocytes, which can be seen in the vitellarium. Two accessory glands, which extend to the oviduct, are also visible. The secretory epithelium of the accessory gland is made up of a dense network of secretory cells surrounded by muscle fibers. Females of A. procerae pierce the tissues of the gall and probably deposit one egg on or close to the pupa of the midge. Aprostocetus procerae is a solitary parasitoid of the midge. The two parasitoids exploit the same host at different developmental stages. These findings improve our knowledge of the reproductive biology of these two parasitoids associated with the African rice gall midge, an important pest in Africa. [source] Effect of the pupal age of Calliphora erythrocephala (Diptera: Calliphoridae) on the reproductive biology of Melittobia acasta (Walker) (Hymenoptera: Chalcidoidea: Eulophidae)ENTOMOLOGICAL SCIENCE, Issue 1 2006Nyiutaha G. IMANDEH Abstract A laboratory experiment was conducted to determine the effect of the pupal age of Calliphora erythrocephala (Meigen) on the reproductive biology (in terms of number, size, developmental time and longevity of progeny) of the parasitoid Melittobia acasta Walker. Melittobia acasta females of uniform size were given five C. erythrocephala pupae from one of four experimental age groups: 17,24 h, 24,48 h, 48,72 h and 72,96 h, for parasitization. The mean number of progeny produced from the experimental age groups for a 24 h period were 2, 7.6, 15.6 and 13.6, respectively. The parasitoids preferred hosts that were 48,72 h old. There were no significant differences in the mean development time (18.2 days) and size of progeny (mean head width = 0.38 ± 0.01 mm) produced from the experimental host age groups. The longevity of progeny from the four host age groups varied (range: 4,39 days), with those from the 48,72 h group living longest (mean = 25 days). The F1 females from the 48,72 h group were reproductively more successful than those from the other groups, producing a mean F2 progeny of 912 individuals when compared with 867, 801 and 757 individuals from the 24,48 h, 72,96 h and 17,24 h age groups, respectively. These findings make significant contributions to our knowledge of the breeding and utilization of this parasitoid for the biological control of dipteran flies in pigsties and poultry houses. [source] Reproductive ecology of DrosophilaFUNCTIONAL ECOLOGY, Issue 5 2008T. A. Markow Summary 1Species of the genus Drosophila reproduce in a wide range of different resources, including fruits, sap, flowers, mushrooms and cacti. Drosophila species and their resources also exhibit considerable variability in geographic distribution. 2Habitat and resource differences pose enormous challenges for Drosophila species. Host chemistry may include highly toxic compounds and breeding sites may be characterized by extreme abiotic conditions such as high and/or low temperature and humidity. 3Drosophila reproductive biology, in terms of morphology, physiology, and behaviour, is as variable among Drosophila species as is their resource use. In some species, adults are ready to reproduce upon emergence, whereas one sex or the other in other species may require weeks to become sexually mature. 4Already a robust system for transmission and population genetic studies, the sequencing of the genomes of 12 diverse Drosophila species now brings the power of genomics to investigators wishing to understand the functional aspects of Drosophila ecology [source] The role of the Species Survival Plan in Maned wolf Chrysocyon brachyurus conservationINTERNATIONAL ZOO YEARBOOK, Issue 1 2010N. SONGSASEN The Association of Zoos and Aquariums Maned Wolf Species Survival Plan (MWSSP) was established almost 25 years ago. The goals of the MWSSP are to (1) maintain a viable self-sustaining captive population in North America, (2) enhance health and well-being of individuals living in North American zoos and (3) promote conservation of this species through education and field-conservation initiatives. Since its inception, the MWSSP and member institutions have supported studies on nutrition, medical management, behaviour and reproductive biology, and published a husbandry manual, which serves as a guide for captive management of Maned wolves Chrysocyon brachyurus in North and South American zoos. Furthermore, the MWSSP has provided funding for field studies aimed at identifying potential threats to wild populations in range countries, including Brazil, Bolivia and Argentina, as well as for the first Population and Habitat Viability Assessment Workshop for this species. Finally, the MWSSP has played an active role in promoting education and outreach efforts in both the United States and range countries. In this paper, we review and discuss the roles of the MWSSP in ex situ and in situ conservation of the Near Threatened Maned wolf. [source] Aspects of the reproductive biology and breeding management of Asian and African elephants Elephas maximus and Loxodonta africanaINTERNATIONAL ZOO YEARBOOK, Issue 1 2006T. B. HILDEBRANDT Elephants possess many unique qualities, including some that relate directly to their reproductive biology. Thus, comparative studies on elephants provide valuable information to the growing biological database for extant mammals. Left undisturbed, Asian Elephas maximus and African Loxodonta Africana elephants reproduce well in the wild. It is ironic then that most captive populations face possible,extinction'because of historically poor reproductive performance. Some of the problems with breeding elephants in captivity are logistical but others, like ovarian and uterine pathologies and bull infertility, have management-related aetiology. Through advances in endocrine monitoring and ultrasound imaging techniques, we are beginning to understand some of the complex mechanisms controlling reproductive function in elephants. Several reproductive characteristics appear to be unique to the taxon, such as luteal steroidogenic function, follicular development patterns, pituitary gonadotrophin secretion, a 22 month-long gestation and musth (in ,,). One example is the,double LH surge'occurring 3 weeks apart during the follicular or non-luteal phase of the cycle, with only the second surge inducing ovulation. These qualities have at times both enhanced and hampered efforts to understand and control reproduction. We have learned that techniques developed for domestic or laboratory species are not always directly applicable to elephants. However, the recent success of artificial insemination based on new ultrasound and endocrine methodology offers hope that establishing selfsustaining populations is possible. This paper reviews our current knowledge of elephant reproduction and how it is being used to aid species conservation for maximal reproductive efficiency and enhancement of genetic management. [source] Sperm morphology in the black coral Cirrhipathes sp. (Anthozoa, Antipatharia)INVERTEBRATE BIOLOGY, Issue 3 2008Elda Gaino Abstract. Male polyps of the antipatharian Cirrhipathes sp., collected along the coral reef of Siladen Island (Sulawesi, Indonesia), were studied in order to gain an insight into the reproductive biology. Spermatocysts (maximum size 120 ,m) are located within the primary gametogenic mesenteries and are separated by mesenteric cell cytoplasmic extensions. Sperm, maturing along radial rows, have a fairly round shape and contain a series of electron-dense vesicles in the apical nuclear region. A single mitochondrion flanks the nucleus. A peculiar cup-like electron-dense body, edged with regularly spaced electron-dense granules, is interposed between the nucleus and the tail, and delimits a central region that includes two centrioles. Cross-sections of the cup-like body reveal that the distal centriole has a pericentriolar system, consisting of nine arms arranged in a radial pattern. Each arm branches into three processes that are connected to the electron-dense granules. Indirect evidence of spawning is derived from the accumulation of sperm in the gastric cavity. This process takes place through the lysis of the cells bordering the mesenteries. Intact cells of this bordering layer appear to be involved in the phagocytosis of non-expelled gametes. [source] Biology and taxonomy of encrusting alcyoniid soft corals in the northeastern Pacific Ocean with descriptions of two new genera (Cnidaria, Anthozoa, Octocorallia)INVERTEBRATE BIOLOGY, Issue 2 2003Catherine S. McFadden Abstract. In this paper we summarize current knowledge of the distribution, ecology, and reproductive biology of 4 encrusting species in the soft coral family Alcyoniidae, with descriptions of 2 new genera and 2 new species. The new genus Discophyton is erected for Alcyonium rudyi, a species common in the lower intertidal of exposed rocky headlands from Vancouver Island, British Columbia, Canada south to Point Lobos, California, USA. Discophyton rudyi n. gen. & n. comb. propagates extensively by clonal fission, giving rise to characteristic aggregations of small, regularly spaced, disc-shaped colonies. We describe 2 new species and place them in a new genus, Thrombophyton. Thrombophyton coronatum n. gen. & n. sp. forms irregularly shaped, membranous colonies on rock surfaces; it occurs subtidally along the southern California coast from the Palos Verdes Peninsula to San Diego and on the California Islands. Thrombophyton trachydermum n. gen. & n. sp. has a similar, membranous growth form; it occurs both intertidally and subtidally on Vancouver Island, British Columbia, Canada, and in the San Juan Archipelago, Washington, and intertidally in central California, USA. Alcyonium pacificum, reported for the first time from North American waters, occurs in subtidal kelp beds around the Aleutian islands of Attu and Adak; its mushroom-shaped colonies are raised above the substrate on a short stalk. D. rudyi, T. trachydermum, and A. pacificum are all gonochores that reproduce in late summer; in contrast, T. coronatum appears to reproduce in the spring. D. rudyi and T. coronatum brood larvae internally to a late planula stage. A key to species is presented for all shallow-water soft corals known to occur in the northeastern Pacific Ocean. [source] A histo-morphological study of the testis of the sharptooth catfish (Clarias gariepinus) as reference for future toxicological assessmentsJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2008J. C. Van Dyk Summary The sharptooth catfish (Clarias gariepinus) has recently been shown to be a useful indicator species of oestrogen polluted waters in South Africa (Barnhoorn et al., 2004). Knowledge of the normal reproductive biology of this species is important to be able to assess the morphological changes caused by the exposure to potentially harmful toxicants including endocrine disruptor chemicals (EDCs). Eleven sexually mature C. gariepinus males were selected from an aquarium population bred through hormone induced spawning in reconstituted reverse osmosis water. The fish were reared under controlled conditions averting exposure to potentially EDCs and allowing the description of the normal testis histomorphology of unexposed healthy specimens. The testes of C. gariepinus are paired elongated organs situated in the dorsal region of the visceral cavity. Histologically, the testes possess a lobular organization enclosed by a thin tunica albuginea. Depending on the tissue region, each seminiferous lobule contains some or all of the various developmental stages of spermatogenesis including a single primary spermatogonia, groups of secondary spermatogonia, cysts of primary and secondary spermatocytes, spermatids, and spermatozoa. Nutritive Sertoli cells are visible on the periphery of the seminiferous lobules. Interstitial tissue (including groups of Leydig cells) and blood vessels constitute most of the interlobular space. It is expected that the histological results of this study will contribute to a currently limited, but growing gonadal histological database for southern African freshwater fish species to serve as reference in future toxicity assessments. [source] Age, growth and reproduction of Marcusenius pongolensis, Oreochromis mossambicus and Schilbe intermedius in an oligotrophic impoundment in SwazilandAFRICAN JOURNAL OF ECOLOGY, Issue 2 2010Anthony J. Booth Abstract The age, growth and reproductive biology of Marcusenius pongolensis, Oreochromis mossambicus and Schilbe intermedius were investigated in the Mnjoli Dam, Swaziland. Otolith annulus formation occurred in winter for M. pongolensis, and in spring/summer for O. mossambicus and S. intermedius. Maximum ages of 8, 6 and 8 years were recorded for M. pongolensis, O. mossambicus and S. intermedius, respectively. Growth was described by the von Bertalanffy growth model as Lt = 238.73(1 , exp,0.27(t+2.27) mm fork length (FL) for M. pongolensis, Lt = 226.83(1 , exp,0.45(t+2.02)) mm total length (TL) for O. mossambicus, and Lt = 214.59(1 , exp,0.60(t+1.20)) mm FL for S. intermedius. Sexual maturity was estimated for male and female M. pongolensis at 134 mm FL and 119 mm FL, respectively. Marcusenius pongolensis matured within their first year. Female O. mossambicus and S. intermedius matured at 239 mm TL and 205 mm FL, corresponding to 2 and 4 years of age, respectively. Extended spawning periods, with two spawning peaks was observed for M. pongolensis, one in spring (September) and the second in autumn (March) and one peak over late-summer for S. intermedius. Résumé L'âge, la croissance et la biologie reproductive de Marcusenius pongolensis, Oreochromis mossambicus et Schilbe intermedius ont étéétudiés dans le barrage de Mnjoli, au Swaziland. La formation des anneaux des otolithes se passe en hiver pour M. pongolensis et au printemps/été pour O. mossambicus et S. intermedius. On a enregistré les âges maximum de 8, 6 et 8 ans respectivement pour Marcusenius pongolensis, Oreochromis mossambicus et Schilbe intermedius. La croissance a été décrite selon le modèle de croissance de von Bertalanffy selon la formule suivante: Lt = 238.73(1 , exp,0.27(t+2.27) mm LF pour M. pongolensis, Lt = 226.83(1 , exp,0.45(t+2.02)) mm LT pour O. mossambicus, et Lt = 214.59(1 , exp,0.60(t+1.20)) mm LF pour S. intermedius. On a estimé que la maturité sexuelle était atteinte à 134 LF et à 119 LF respectivement pour le mâle et la femelle de M. pongolensis, qui arrivaient à maturité au cours de leur première année. Les femelles d'O. mossambicus et de S. intermedius devenaient matures à 239 mm LT et 205 mm LF, ce qui correspond à l'âge de 2 et de 4 ans, respectivement. On a observé des périodes de frai prolongées, avec deux périodes de frai pour M. pongolensis, une au printemps (septembre) et la seconde en automne (mars), et un pic en fin d'été pour S. intermedius. [source] | ||||||||||||||||||||||||||||||||||||||||