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Assessing Paternity in Japanese Quails (Coturnix Japonica) Using Microsatellite Markers - Inferences for Its Mating System and Reproductive Success

Gomes, M. L.; Hatanaka, T.; Campos, W. N. de; Wasko, A. P.
Fonte: Facta-fundacio Arnco Ciência Tecnologia Avicolas Publicador: Facta-fundacio Arnco Ciência Tecnologia Avicolas
Tipo: Artigo de Revista Científica Formato: 329-338
ENG
Relevância na Pesquisa
45.89%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Microsatellite markers were analyzed in Japanese quails, Coturnix japonica, using different methodologies (PAGE and automated genotyping), in order to evaluate their use in paternity testing. Ten animal triplets composed by a female and two males were used to mate and generate an offspring. Paternity was determined in five-day-old embryos, and the data generated by fluorescent labeled and tailored primers in PCR and further automated genotyping were robust. Three microsatellite markers were polymorphic (Na = 5-8, H-E = 0.75) and no loci were found to deviate significantly from Hardy-Weinberg equilibrium or showed any evidence of linkage disequilibrium (p > 0.05). A slight heterozygote deficiency and some incompatibilities between the female known parent and its offspring that involved homozygous genotypes were observed at GUJ0001 locus and may indicate the presence of null alleles. Although a reduced set of microsatellite primers were applied, it was possible to determine the paternity of 96.87% of the embryos, using combined data of three loci. The approach was useful for parentage inferring in a captive population of C. japonica and the results evidenced a potential polyandric mating system in the species...

Assessing paternity in japanese quails (Coturnix japonica) using microsatellite markers - inferences for its mating system and reproductive success

Gomes,ML; Hatanaka,T; Campos,WN de; Wasko,AP
Fonte: Fundação APINCO de Ciência e Tecnologia Avícolas Publicador: Fundação APINCO de Ciência e Tecnologia Avícolas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
Relevância na Pesquisa
45.89%
Microsatellite markers were analyzed in Japanese quails, Coturnix japonica, using different methodologies (PAGE and automated genotyping), in order to evaluate their use in paternity testing. Ten animal triplets composed by a female and two males were used to mate and generate an offspring. Paternity was determined in five-day-old embryos, and the data generated by fluorescent labeled and tailored primers in PCR and further automated genotyping were robust. Three microsatellite markers were polymorphic (Na = 5-8, H E = 0.75) and no loci were found to deviate significantly from Hardy-Weinberg equilibrium or showed any evidence of linkage disequilibrium (p > 0.05). A slight heterozygote deficiency and some incompatibilities between the female known parent and its offspring that involved homozygous genotypes were observed at GUJ0001 locus and may indicate the presence of null alleles. Although a reduced set of microsatellite primers were applied, it was possible to determine the paternity of 96.87% of the embryos, using combined data of three loci. The approach was useful for parentage inferring in a captive population of C. japonica and the results evidenced a potential polyandric mating system in the species, in which no advantage mechanism of last-male sperm precedence seems to occur.

Biases in sperm use in the mallard: no evidence for selection by females based on sperm genotype

Cunningham, E. J. A.; Cheng, K. M.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 07/05/1999 EN
Relevância na Pesquisa
36.21%
If we are to understand fully the factors influencing fertilization success, it is essential to untangle male and female effects on sperm use. In many species, differences in fertilizing ability have been found between males or male genotypes, but the impact of female effects is less clear and may vary between taxa. Here, we examine sperm use in the mallard (Anas platyrhynchos), a species of bird in which forced copulation forms a major component of the mating system, to investigate whether there is any evidence for post-insemination female choice or rejection of particular sperm genotypes. Current models of sperm use in birds suggest observed patterns of paternity are a result of passive sperm loss from the reproductive tract and the relative timing of inseminations. Although this type of model successfully predicted average values of last male precedence observed in this species, there was considerable variation between females in their pattern of sperm use, with a tendency for females to use sperm of a single genotype. However, females did not consistently prefer one genotype over another in repeated inseminations with identical sperm mixtures, suggesting that post-insemination female preference based on sperm genotype did not account for this variation.

Female age and sperm competition: last-male precedence declines as female age increases.

Mack, Paul D; Priest, Nicholas K; Promislow, Daniel E L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 22/01/2003 EN
Relevância na Pesquisa
66.41%
Until very recently, most studies of sperm competition have focused on variation in male competitive ability. However, we now know that a number of reproductive traits, including oviposition rate, use of stored sperm and receptivity to mating, vary with female condition. Because females can play an active part in the movement of sperm within their reproductive tract, sperm competition may be influenced by female condition. Existing studies of sperm competition in fruitflies ignore the effects of female condition, using females that are 3-4 days old and in their reproductive prime. But condition will decline as a female senesces. Here, we examine the effect of female age on the outcome of sperm competition in three strains of the fruitfly, Drosophila melanogaster. Previous studies have shown that female age influences preference for mates and male ejaculation strategies. In this study, we find that when males are mated to females that are older than 17 days, last-male sperm precedence decreases significantly. These results could lead to a greater understanding of the physiological mechanisms that regulate the outcome of sperm competition.

Drosophila melanogaster females change mating behaviour and offspring production based on social context

Billeter, Jean-Christophe; Jagadeesh, Samyukta; Stepek, Nancy; Azanchi, Reza; Levine, Joel D.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.98%
In Drosophila melanogaster, biological rhythms, aggression and mating are modulated by group size and composition. However, the fitness significance of this group effect is unknown. By varying the composition of groups of males and females, we show that social context affects reproductive behaviour and offspring genetic diversity. Firstly, females mating with males from the same strain in the presence of males from a different strain are infecund, analogous to the Bruce effect in rodents, suggesting a social context-dependent inbreeding avoidance mechanism. Secondly, females mate more frequently in groups composed of males from more than one strain; this mitigates last male sperm precedence and increases offspring genetic diversity. However, smell-impaired Orco mutant females do not increase mating frequency according to group composition; this indicates that social context-dependent changes in reproductive behaviour depend on female olfaction, rather than direct male–male interactions. Further, variation in mating frequency in wild-type strains depends on females and not males. The data show that group composition can affect variance in the reproductive success of its members, and that females play a central role in this process. Social environment can thus influence the evolutionary process.

Comparison of reproductive traits of regular and irradiated male desert locust Schistocerca gregaria (Orthoptera: Acrididae): Evidence of last-male sperm precedence

Dushimirimana, Severin; Hance, Thierry; Damiens, David
Fonte: The Company of Biologists Publicador: The Company of Biologists
Tipo: Artigo de Revista Científica
Publicado em 01/02/2012 EN
Relevância na Pesquisa
56.11%
The sterile insect technique (SIT) is increasingly used to control pest insect populations. The success of SIT control programs depends on the ability to release sterile males and on the capacity of sterile males to compete with wild males to inseminate wild females. In this study, we evaluated the mating performance of Schistocerca gregaria (Försk.) males irradiated with 4 Gray. We compared reproductive traits, such as duration of precopulation time, mating duration, quantity of sperm stored by females after copulation, number of females mated successively and postmating competition of irradiated males with non-irradiated males. Irradiated males were able to mate but the resulting number of offspring was dramatically reduced compared to the average number of offspring observed during a regular mating. During a single copulation, irradiated males transferred fewer sperm than regular males but, theoretically, this quantity is enough to fertilize all the eggs produced by a female during its reproductive life. Irradiated males also had the ability to remove sperm from a previous mating with unirraditated males. This new information on the mating strategies helps explain the post-copulation guarding behaviour of S. gregaria.

Do Candidate Genes Mediating Conspecific Sperm Precedence Affect Sperm Competitive Ability Within Species? A Test Case in Drosophila

Civetta, Alberto; Finn, Scott
Fonte: Genetics Society of America Publicador: Genetics Society of America
Tipo: Artigo de Revista Científica
Publicado em 16/07/2014 EN
Relevância na Pesquisa
46.4%
When females mate to multiple males, the last male to mate fathers the majority of progeny. When males of different species inseminate a female, the sperm of the male conspecific to the female is favored in fertilization in a process known as conspecific sperm precedence (CSP). A large number of studies in Drosophila have assayed the genetic basis of sperm competition, with a main focus on D. melanogaster and accessory gland protein genes. Only a few studies have attempted to disentangle the genetic basis of CSP between related species of Drosophila. Although there is no a priori reason to believe that genes influencing intraspecific sperm competitive ability might also mediate conspecific sperm precedence, no study has addressed the question. Here, we test a group of candidate CSP genes between D. simulans and D. mauritiana for their effect on sperm competition in D. melanogaster. The use of P-element insertion lines identified CG14891 gene disruption as the only one causing a significant decrease in second male paternity success relative to wild-type and ebony tester males. The gene disruption affected both sperm displacement and the sperm fertilizing ability. Out of five genes tested using RNA interference, only gene knockdown of CG6864 (Mst89B) significantly reduced the male’s ability to father progeny when second to mate. Our results suggest that CG14891 and CG6864 might have been co-opted from an intraspecies gene function (i.e....

Polyandry as a hedge against genetic incompatibility

Zeh, Jeanne Anne
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
46.36%
Why do females across a wide range of taxa mate with more than one male? Here, I present the hypothesis that females engage in polyandry as a hedge against genetic incompatibility. I review evidence from the literature showing that the genomes of species are dynamic entities, constantly evolving as a consequence of genetic conflicts within and between the nucleus and the cytoplasm. Cellular endosymbionts, segregation distorter alleles, transposable elements and genomically-imprinted genes can all threaten female fitness by modifying maternal and paternal haplotypes in ways that render them incompatible within the developing embryo. I discuss the potential for polyandrous females to utilize postcopulatory mechanisms such as sperm competition, female choice of sperm, and reallocation of maternal resources from defective to viable embryos in order to minimize the risk and/or cost of fertilization by genetically-incompatible sperm. In a sperm precedence experiment carried out on the pseudoscorpion, Cordylochernes scorpioides, single-locus minisatellite DNA fingerprinting demonstrated strong last-male sperm precedence when females were mated to two males which broke down completely when females were mated to three males. This result indicates that the opportunity for postcopulatory sexual selection may be much greater in nature than is evident from standard...

Sperm utilization patterns in Gryllus integer (orthoptera: gryllidae

Backus, Vickie Lynn.
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
ENG
Relevância na Pesquisa
36.58%
Sperm competition is the competition for fertilizations between ejaculates, within a female, following multiple mating. There are four sperm utilization or precedence patterns: first male precedence, where the first male to mate fertilizes most of the eggs laid by a female; last male precedence, where the last male to mate fertilizes most of the eggs laid by a female; "all-or-none" pattern, where sperm from either male fertilizes all the eggs laid by a female but which male's sperm that is used is random; or sperm mixing, where sperm from each male is used equally in fertilizing eggs laid by a female. Intermediate utilization patterns are also possible. Sperm competition occurs in a wide variety of insect species as well as other animals. This study was undertaken to study sperm competition in the field cricket, Gryllus integer. Four experiments were conducted: a radiation and sterilization experiment, a diapause experiment, and 2 competition experiments. It was found that 7,000 rad of gamma radiation sterilized adult ~ integer males. There was no diapause in the laboratory in ~ integer eggs. In the first competition experiment, three groups of females were used: females mated with a normal male, then with a second normal male (NN group); females mated with a normal male...

Traumatic insemination and sexual conflict in the bed bug Cimex lectularius

Stutt, Alastair D.; Siva-Jothy, Michael T.
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.98%
The bed bug, Cimex lectularius, has a unique mode of copulation termed “traumatic” insemination [Carayon, J. (1966) in Monograph of the Cimicidae, ed. Usinger, R. (Entomol. Soc. Am., Philadelphia), pp. 81–167] during which the male pierces the female's abdominal wall with his external genitalia and inseminates into her body cavity [Carayon, J. (1966) in Monograph of the Cimicidae, ed. Usinger, R. (Entomol. Soc. Am., Philadelphia), pp. 81–167]. Under controlled natural conditions, traumatic insemination was frequent and temporally restricted. We show for the first time, to our knowledge, that traumatic insemination results in (i) last-male sperm precedence, (ii) suboptimal remating frequencies for the maintenance of female fertility, and (iii) reduced longevity and reproductive success in females. Experimental females did not receive indirect benefits from multiple mating. We conclude that traumatic insemination is probably a coercive male copulatory strategy that results in a sexual conflict of interests.

Female genotypes affect sperm displacement in Drosophila.

Clark, A G; Begun, D J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1998 EN
Relevância na Pesquisa
36.19%
Differential success of sperm is likely to be an important component of fitness. Extensive variation among male genotypes in competitive success of sperm in multiply mated females has been documented for Drosophila melanogaster. However, virtually all previous studies considered the female to be a passive vessel. Nevertheless, under certain conditions female fitness could be determined by her role in mediating use of sperm from multiple males. Here we ask whether females differ among genotypes in their tendency to exhibit last-male precedence. Competition of sperm from two tester male genotypes (bwD and B3-09, a third-chromosome isogenic line from Beltsville, MD) was quantified by doubly mating female lines that had been rendered homozygous for X, second, or third chromosomes isolated from natural populations. The composite sperm displacement parameter, P2', was highly heterogeneous among lines, whether or not viability effects were compensated, implying the presence of polymorphic genes affecting access of sperm to eggs. Genetic variation of this type is completely neutral in the absence of pleiotropy or interaction between variation in the two sexes.

'Sloppy' sperm mixing and intraspecific variation in sperm precedence (P2) patterns.

Harvey, I F; Parker, G A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 22/12/2000 EN
Relevância na Pesquisa
46.38%
Sperm precedence patterns are typically highly variable within (and between) species. Intraspecific variation in sperm precedence (measured as P2, the proportion of progeny fathered by the last male to mate' is frequently seen as a candidate for adaptive interpretation through either male effects (e.g. body size), female effects (e.g. cryptic female choice) or an interaction between the two. Here we show, using computer simulation, that if ejaculates divide into a number of 'packets' and packets from two males mix randomly, then a variety of patterns of sperm precedence may result. We term this process 'sloppy' mixing. If ejaculates break into a small number of packets, bimodal P2 distributions are predicted. As the number of packets is increased, then a complex series of changes through multimodal and flat to unimodal distributions results. Sloppy mixing can thus result in many of the observed P2 distributions. Sloppy mixing is unlikely to change the predictions of adaptive models of sperm competition.

Fertilization by proxy: rival sperm removal and translocation in a beetle

Haubruge, E.; Arnaud, L.; Mignon, J.; Gage, M. J. G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 07/06/1999 EN
Relevância na Pesquisa
56.44%
Competition between different males' sperm for the fertilization of ova has led to the evolution of a diversity of characters in male reproductive behaviour, physiology and morphology. Males may increase sperm competition success either by enhancing the success of their own sperm or by negating or eliminating the success of rival sperm. Here, we find that in the flour beetle Tribolium castaneum, the second male to mate gains fertilization precedence over previous males' sperm and fertilizes approximately two-thirds of the eggs. It is not known what mechanism underlies this pattern of last-male sperm precedence; however, the elongate tubules of the female sperm storage organ may encourage a 'last-in, first-out' sperm use sequence. Here we present an additional or alternative mechanism of sperm precedence whereby previously deposited sperm are removed from the female tract by the mating male's genitalia. In addition to providing evidence for sperm removal in T. castaneum, we also show that removed, non-self sperm may be translocated back into the reproductive tracts of new, previously unmated females, where the translocated sperm go on to gain significant fertilization success. We found that, in 45 out of 204 crosses, sperm translocation occurred and in these 45 crosses over half of the offspring were sired by spermatozoa which had been translocated between females on the male genitalia. In the natural environment of stored food...

Partitioning sexual selection into its mating success and fertilization success components

Pischedda, Alison; Rice, William R.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.11%
Postcopulatory sexual selection due to sperm competition and/or cryptic female choice has been documented in a diversity of taxonomic groups and is considered a pivotal component of sexual selection. Despite this apparent importance, the relative contribution of postcopulatory fertilization success to overall sexual selection has not yet been measured in any species. Here, we used a laboratory-adapted population of the promiscuous fruit fly Drosophila melanogaster to partition the variance in male reproductive success into mating success (a major component of precopulatory sexual selection) and fertilization success (a major component of postcopulatory sexual selection). We found that fertilization success contributed nearly as strongly as mating success to a male's net performance in sexual selection, but that most of this postcopulatory component was attributable to variation in male mating order (the tendency to be the last male to mate a female). After adjusting for mating order, only ≈2% of the residual variation in male reproductive success was attributable to differential fertilization success. We found no correlation between male mating success and fertilization success in this system. Unlike natural populations of Drosophila...

Aspetti del sistema nuziale del Punteruolo rosso delle palme (Rhynchophorus ferrugineus): un approccio molecolare e bioinformatico.

BELVEDERE, SILVIA
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
IT
Relevância na Pesquisa
86.22%
Il Punteruolo rosso delle palme, Rhynchophorus ferrugineus, Olivier (Curculionoidea, Dryophtoridae), è un coleottero originario del Sud-Est asiatico e della Melanesia invasivo in Medio Oriente ed in quasi tutti i paesi del bacino del Mediterraneo, compresa l'Italia. Il fitofago arreca ingenti danni a numerose specie di Arecaceae, tra cui molte palme di interesse economico. Le attuali azioni di controllo integrato, adottate per contenerne l'espansione, si sono rivelate finora insufficienti anche perché manca una approfondita conoscenza del sistema nuziale dell'insetto, ed il suo grande successo riproduttivo è proprio una delle cause principali del enorme potenziale invasivo di questa specie dannosa. Obiettivo generale del progetto di dottorato è stato dunque lo studio di aspetti del mating system del Punteruolo rosso legati ad eventuali comportamenti poliandrici e fenomeni di selezione sessuale post-copulatoria. Sono stati eseguiti a questo scopo dei test di paternità, per mezzo di analisi genetiche e bioinformatiche, sulla prole di esperimenti di incrocio effettuati in laboratorio, in modo da verificare ipotesi alternative riguardanti il sistema nuziale della specie. Date le scarse informazioni genetiche disponibili su R. ferrugineus...

Sexual selection when fertilization is not guaranteed

Kokko, Hanna; Mappes, Johanna
Fonte: Society for the Study of Evolution Publicador: Society for the Study of Evolution
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
56.18%
Much of the theory of sexual selection assumes that females do not generally experience difficulties getting their eggs fertilized, yet sperm limitation is occasionally documented. How often does male limitation form a selection for female traits that improve their mating rate? The question is difficult to test, because if such traits evolve to be efficient, sperm limitation will no longer appear to be a problem to females. Here, we suggest that changes in choosiness between populations, and in particular between virgin and mated females, offer an efficient way to test this hypothesis. We model the "wallflower effect," that is, changes in female preferences due to time and mortality costs of remaining unmated (for at least some time). We show that these costs cause adaptive reductions of female choice, even if mate encounter rates appear high and females only rarely end their lives unfertilized. We also consider the population consequences of plastic or fixed mate preferences at different mate encounter rates. If mate choice is plastic, we confirm earlier verbal models that virgins should mate relatively indiscriminately, but plastic increase of choosiness in later matings can compensate and intensify sexual selection on the male trait...

Influence of alternate reproductive tactics and pre- and postcopulatory sexual selection on paternity and offspring performance in a lizard

Keogh, J Scott; Umbers, Kate; Wilson, Eleanor; Stapley, Jessica; Whiting, Martin J.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26%
Sexual selection theory predicts different optima for multiple mating in males and females. We used mating experiments and genetic paternity testing to disentangle pre- and postcopulatory mechanisms of sexual selection and alternate reproductive tactics in the highly promiscuous lizard Eulamprus heatwolei. Both sexes mated multiply: 30-60 % of clutches were sired by two to four fathers, depending on the experiment. Larger males sired more offspring when we allowed male contest competition: 52 % of large males but only 14 % of small males sired at least one offspring. In the absence of male contest competition, females mated promiscuously and there was no large male advantage: 80 % of large males and 90 % of small males sired at least one offspring, and there was no evidence for last-male precedence. Multiple mating did not yield obvious direct or indirect benefits to females. E. heatwolei represents a complex system in which males attempt to improve their fertility success by limiting rivals from access to females and through adopting alternate reproductive tactics. Conversely, females exhibit no obvious precopulatory mate choice but may influence fitness through postcopulatory means by either promoting sperm competition or through cryptic female choice. Our results support the hypothesis that female multiple mating in nonavian reptiles is best explained by the combined effect of mate encounter frequency and high benefits to males but low costs to females.