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Sexual Performance (sexual + performance)
Selected AbstractsMethoprene modulates the effect of diet on male melon fly, Bactrocera cucurbitae, performance at mating aggregationsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2010Ihsan ul Haq Abstract The effect of access to dietary protein (P) (hydrolyzed yeast) and/or treatment with a juvenile hormone analogue, methoprene (M), (in addition to sugar and water) on male aggregation (lekking) behaviour and mating success was studied in a laboratory strain of the melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). Six-day-old males were treated with (1) protein and methoprene (M+P+), (2) only protein (M,P+), or (3) only methoprene (M+P,), and compared with 14-day-old sexually mature untreated males (M,P,). The lekking behaviour of the four groups of males when competing for virgin sexually mature females (14,,16 days old) was observed in field cages. The following parameters were measured at male aggregations: lek initiation, lek participation, males calling, male,male interaction, female acceptance index, and mating success. For all these parameters, the M+P+ males significantly outperformed the other males. Moreover, for all parameters, there was a similar trend with M+P+ > M,P+ > M,P, > M+P,. More M+P+ males called and initiated and participated in lek activities than all other types of male, which resulted in higher mating success. They had also fewer unsuccessful copulation attempts than their counterparts. Whereas treatment with methoprene alone had a negative effect in young males with only access to sugar, access to dietary protein alone significantly improved young male sexual performance; moreover, the provision of methoprene together with protein had a synergistic effect, improving further male performance at leks. The results are of great relevance for enhancing the application of the sterile insect technique (SIT) against this pest species. The fact that access to dietary protein and treatment of sterile males with methoprene improves mating success means that SIT cost-effectiveness is increased, as more released males survive to sexual maturity. [source] Severely reduced sexual reproduction in northern populations of a clonal plant, Decodonverticillatus (Lythraceae)JOURNAL OF ECOLOGY, Issue 3 2001Marcel E. Dorken Summary 1,In flowering plants the balance between sexual and clonal, asexual reproduction can vary widely. We quantified variation in sexual reproduction in a tristylous, clonal, aquatic plant, Decodon verticillatus, and investigated the role of ecological and genetic factors in causing this variation. 2,We surveyed components of sexual fertility and vegetative growth in 28 populations distributed along a 500-km latitudinal transect in New England, USA. Northerly populations tend to be monomorphic (M) for style length, and probably therefore have reduced sexual reproduction compared with southerly, trimorphic (T) populations. 3,Compared with T populations (n = 10), M populations (n = 18) exhibited large reductions for all components of sexual reproduction, including flower production, pollen deposition, pollen tube growth, fertilization, fruit set and seeds per fruit. Seven M populations produced no seed at all, and the other 11 very little (mean = 24 vs. 1139 seeds per plant in trimorphic populations). Clonal propagation was also greatly reduced in M populations. 4,A survey of three polymorphic allozyme loci detected only single, usually heterozygous, genotypes in 15 M populations, whereas all T populations were genotypically diverse. The other three M populations contained three or fewer genotypes and one always predominated. Sexual recruitment is therefore extremely rare. 5,Comparison of the sexual fertility of M and T populations in a concurrent common glasshouse experiment with our field data revealed that reduced sexual performance in northern M populations is principally due to genetic factors, but is also caused by ecological factors that covary with latitude. 6,This abrupt shift away from sexual reproduction in populations at the northern periphery of the geographical range in D. verticillatus may greatly limit their evolutionary potential and restrict further northward expansion. [source] Oestrogen Receptor , is Essential for Female-Directed Chemo-Investigatory Behaviour but is not Required for the Pheromone-Induced Luteinizing Hormone Surge in Male MiceJOURNAL OF NEUROENDOCRINOLOGY, Issue 2 2000S. R. Wersinger The expression of normal masculine sexual behaviour requires testosterone. Testosterone can bind to androgen receptors, either in its native form, or after reduction to other androgen metabolites. In addition, testosterone can be aromatized to oestrogen, and bind to oestrogen receptor , and/or ,. Male copulatory behaviour is deficient in mice lacking functional oestrogen receptor , gene (ER,KO mice). We sought to determine which aspect(s) of masculine sexual behaviour is compromised in the ER,KOs. Specifically, we asked whether ER,KO males have reduced motivation and/or an inability to recognize oestrous females. We found significant differences between mice of different genotypes in the amount of chemo-investigatory behaviour displayed and in the target of their investigation. Wild-type males spent more time investigating ovariectomized, oestradiol-treated females, than either males, or ovariectomized females that had not received hormone priming. ER,KO males spent little time investigating any of the stimulus mice and showed no preferences. To test the hypothesis that this lack of chemo-investigatory behaviour is due to the inability of ER,KO males to detect and respond to female pheromones, we exposed males to chemosensory cues (soiled bedding) from females. Males resided in clean, or female-soiled, cage bedding for 60 min. Next, blood was collected and plasma luteinizing hormone (LH) assayed. We also assessed Fos-like immunoreactivity (Fos-ir) in several neural regions involved in processing chemosensory cues. Despite the fact that male ER,KOs spend little time engaged in chemo-investigation of females, their neuroendocrine responses to female-soiled bedding were similar to those seen in wild-type males. Our data suggest that the normal coupling between the neuroendocrine response to females and the generation of sexual behaviour is disrupted in ER,KO mice. Responses to female pheromones do not require ER,. However, normal male sexual performance requires the ER, gene. [source] The Majority of Men with Lifelong Premature Ejaculation Prefer Daily Drug Treatment: An Observation Study in a Consecutive Group of Dutch MenTHE JOURNAL OF SEXUAL MEDICINE, Issue 4i 2007Marcel D. Waldinger MD ABSTRACT Introduction., Whether men with lifelong premature ejaculation (PE) prefer on-demand drug treatment to delay ejaculation time to daily drug treatment, has never been studied as a separate study question. Aim., To study how men with lifelong PE feel about the use of serotonergic antidepressants, and which option they would prefer for themselves: either a daily drug, a drug to be used on demand, or a topical anesthetic cream to be applied on demand. Main Outcome Measures., Treatment preference was determined by questionnaire. Methods., An observational questionnaire survey in a clinical sample. Preferences of different treatment strategies were queried before and after standard efficacy and safety information. Results., A consecutive group of 88 men with lifelong PE who decided for themselves to be seen for rapid ejaculation was studied. The age was 37 ± 11 years (mean ± SD), range 18,64 years. None of these men was ever treated for PE and 21% used medication that did not affect sexual performance. Of them, 71 (81%) preferred a drug for daily use, 14 (16%) a drug on demand, while three men preferred topical anesthetic cream. Those men who initially preferred daily treatment did not change their view after standard information about efficacy and side effects, while 9 of 17 men who initially preferred on-demand drug treatment had switched their preferences to daily oral drug usage. Around 60% of men did not care about the nature of the drug, i.e., an antidepressant. The most frequently reported argument to prefer daily drug treatment was that this strategy would have the least effects toward the spontaneity of having sex. Conclusion., As opposed to agents that must be taken 4,6 hours prior to coitus and with the methods used here, this group of Dutch men with lifelong PE favor uninterrupted daily drug treatment to delay ejaculation mainly because daily treatment guarantees no interference with the spontaneity of having sex. Waldinger MD, Zwinderman AH, Olivier B, and Schweitzer DH. The majority of men with lifelong premature ejaculation prefer daily drug treatment: An observation study in a consecutive group of Dutch men. J Sex Med 2007;4:1028,1037. [source] Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trialANDROLOGIA, Issue 2 2009T. Zenico Summary Lepidium meyenii (Maca) is a cultivated root belonging to the brassica family used in the Andean region for its supposed aphrodisiac properties. We carried out a double-blind clinical trial on 50 Caucasian men affected by mild erectile dysfunction (ED), randomised to treatment with Maca dry extract, 2400 mg, or placebo. The treatment effect on ED and subjective well-being was tested administrating before and after 12 weeks the International Index of Erectile Function (IIEF-5) and the Satisfaction Profile (SAT-P). After 12 weeks of treatment, both Maca- and placebo-treated patients experienced a significant increase in IIEF-5 score (P < 0.05 for both). However, patients taking Maca experienced a more significant increase than those taking placebo (1.6 ± 1.1 versus 0.5 ± 0.6, P < 0.001). Both Maca- and placebo-treated subjects experienced a significant improvement in psychological performance-related SAT-P score, but the Maca group higher than that of placebo group (+9 ± 6 versus +6 ± 5, P < 0.05). However, only Maca-treated patients experienced a significant improvement in physical and social performance-related SAT-P score compared with the baseline (+7 ± 6 and +7 ± 6, both P < 0.05). In conclusion, our data support a small but significant effect of Maca supplementation on subjective perception of general and sexual well-being in adult patients with mild ED. [source] | |||||||||||||