Assuring paternity in a promiscuous world: are there lessons for ticks among the insects?

Parasitology ◽  
2004 ◽  
Vol 129 (S1) ◽  
pp. S145-S160 ◽  
Author(s):  
W. R. KAUFMAN
Keyword(s):  
Female Fecundity ◽  
Male Factor ◽  
Physiological Factors ◽  
Accessory Glands ◽  
The Future ◽  
Mating Choice ◽  
Stimulating Factor ◽  
Male Factors

In this article I begin with a few current ideas on some physiological factors that influence mating choice in insects. Emphasis is placed on those proteins produced by the male reproductive accessory glands which increase female fecundity and reduce her receptivity to subsequent males. Strategies used by late-arriving males to favour their paternity are also mentioned. With a number of insect models as background, I then review what is currently known about several male factors in ticks (a capacitation factor, a male factor, an engorgement factor and a vitellogenesis stimulating factor) and suggest where we might focus our experimental activities in the future.

scholarly journals Paternal effects correlate with female reproductive stimulation in the polyandrous ladybirdCheilomenes sexmaculata

2014 ◽  
Vol 104 (4) ◽  
pp. 480-485 ◽  
Author(s):  
M.A. Mirhosseini ◽  
J.P. Michaud ◽  
M.A. Jalali ◽  
M. Ziaaddini
Keyword(s):  
Female Reproduction ◽  
Paternal Effects ◽  
Female Fecundity ◽  
Adult Weight ◽  
Male Age ◽  
Mating History ◽  
Epigenetic Effects ◽  
Seminal Fluids ◽  
Egg Fertility ◽  
Male Factors

AbstractComponents of male seminal fluids are known to stimulate fecundity and fertility in females of numerous insect species and paternal effects on offspring phenotype are also known, but no studies have yet demonstrated links between male effects on female reproduction and those on progeny phenotype. In separate laboratory experiments employing 10-day-old virgin females ofCheilomenes sexmaculata(F.), we varied male age and mating history to manipulate levels of male allomones and found that the magnitude of paternal effects on progeny phenotype was correlated with stimulation of female reproduction. Older virgin males remained in copula longer than younger ones, induced higher levels of female fecundity, and sired progeny that developed faster to yield heavier adults. When male age was held constant (13 days), egg fertility declined as a function of previous male copulations, progeny developmental times increased, and the adult weight of daughters declined. These results suggest that male epigenetic effects on progeny phenotype act in concert with female reproductive stimulation; both categories of effects increased as a consequence of male celibacy (factor accumulation), and diminished as a function of previous matings (factor depletion). Male factors that influence female reproduction are implicated in sexual conflict and parental effects may extend this conflict to offspring phenotype. Whereas mothers control the timing of oviposition events and can use maternal effects to tailor progeny phenotypes to prevailing or anticipated conditions, fathers cannot. Since females remate and dilute paternity in polyandrous systems, paternal fitness will be increased by linking paternal effects to female fecundity stimulation, so that more benefits accrue to the male's own progeny.

scholarly journals Epigenetic reprogramming during spermatogenesis and male factor infertility

Reproduction ◽  
2018 ◽  
Vol 156 (2) ◽  
pp. R9-R21 ◽  
Author(s):  
H M McSwiggin ◽  
A M O’Doherty
Keyword(s):  
Dna Methylation ◽  
Male Infertility ◽  
Deep Sequencing ◽  
Male Factor Infertility ◽  
Male Factor ◽  
Chromatin Dynamics ◽  
Sequencing Technologies ◽  
Male Germline ◽  
Male Factors ◽  
Epigenetic Processes

Infertility is an often devastating diagnosis encountered by around one in six couples who are trying to conceive. Moving away from the long-held belief that infertility is primarily a female issue, it is now recognised that half, if not more, of these cases may be due to male factors. Recent evidence has suggested that epigenetic abnormalities in chromatin dynamics, DNA methylation or sperm-borne RNAs may contribute to male infertility. In light of advances in deep sequencing technologies, researchers have been able to increase the coverage and depth of sequencing results, which in turn has allowed more comprehensive analyses of spermatozoa chromatin dynamics and methylomes and enabled the discovery of new subsets of sperm RNAs. This review examines the most current literature related to epigenetic processes in the male germline and the associations of aberrant modifications with fertility and development.

scholarly journals Seminal Fluid Metabolomic Markers of Oligozoospermic Infertility in Humans

Metabolites ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 64 ◽  
Author(s):  
Federica Murgia ◽  
Valentina Corda ◽  
Marianna Serrenti ◽  
Valeria Usai ◽  
Maria Laura Santoru ◽  
...  
Keyword(s):  
Seminal Fluid ◽  
Partial Least Square ◽  
Least Square ◽  
Resonance Spectroscopy ◽  
Fluid Composition ◽  
Male Factor ◽  
Metabolic Fingerprint ◽  
Infertility Patients ◽  
Male Factors

Infertility affects 12–15% of couples worldwide, and male factors are the cause of nearly half of all cases. Studying seminal fluid composition could lead to additional diagnostic accuracy and a better understanding of the pathophysiology of male factor infertility. Metabolomics offers a new opportunity to evaluate biomarkers and better understand pathological mechanisms. The aim of the study was to identify new markers or therapeutic targets to improve outcomes in male factor or idiopathic infertility patients. Semen samples were obtained from 29 men with a normal spermogram test, and from 18 oligozoospermic men. Samples were processed and analyzed by Nuclear Magnetic Resonance spectroscopy and, subsequently, multivariate and univariate statistical analyses. Receiving Operator Curves (ROC) and Spearman correlations were also performed. An Orthogonal Partial Least Square Discriminant Analysis supervised multivariate model was devised to compare the groups. The levels of fructose, myo-inositol, aspartate and choline were altered. Moreover, Spearman Correlation associated fructose, aspartate and myo-inositol with the total amount of spermatozoa, total motile spermatozoa, % of immotility and % of “in situ” spermatozoic motility respectively. NMR-based metabolomics allowed the identification of a specific metabolic fingerprint of the seminal fluids of patients affected by oligozoospermia.

scholarly journals Epidemiologic aspects of male infertility

2017 ◽  
Vol 6 (8) ◽  
pp. 3362 ◽  
Author(s):  
Arunadevi Velu ◽  
Geetha Prasad
Keyword(s):  
Alcohol Consumption ◽  
Associated Factors ◽  
Male Partner ◽  
Medical Sciences ◽  
Male Factor ◽  
Cross Sectional ◽  
Infertile Men ◽  
Smoking Exposure ◽  
History Of ◽  
Male Factors

Background: Infertility affects 10-15% of couples worldwide with rates steadily increasing in the Industrialized world, in part due to the deterioration of male reproductive health.Methods: This study was performed in an attempt to clarify the associated factors that might play a role in group of Indian infertile men. This study was a cross – sectional descriptive study conducted in Karpaga Vinayaga Institute of Medical Sciences. The information was obtained from the men who had attended the clinic from January 2016-January 2017. The factors that were studied in this research are the demographic characteristics, alcohol consumption, smoking, exposure to heavy metals, obesity, stress and history of surgery.Results: In 31.6% of couples, the cause of infertility was pure male factor and in 20.4% of them the problem was related to male and female factor both. The most important associated factors for male factor included history of varicocele operation (24%), alcohol consumption (18%) and cigarette smoking (16%).Conclusions: Male factors play a significant role in up to 50 percent of infertility cases, stressing the need for a logical, stepwise approach to the evaluation of the male partner.

scholarly journals A Comparison of Pattern of Pregnancy Loss in Women with Infertility Undergoing IVF and Women with Unexplained Recurrent Miscarriages Who Conceive Spontaneously

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Vidya A. Tamhankar ◽  
Beiyu Liu ◽  
Junhao Yan ◽  
Tin-Chiu Li
Keyword(s):  
Pregnancy Loss ◽  
Loss Rate ◽  
Unexplained Infertility ◽  
Clinical Pregnancy ◽  
Male Factor ◽  
Recurrent Miscarriages ◽  
Group I ◽  
Tubal Factor ◽  
Group Ii ◽  
Male Factors

Objective. Women with infertility and recurrent miscarriages may have an overlapping etiology. The aim of this study was to compare the pregnancy loss in pregnancies after IVF treatment with spontaneous pregnancies in women with recurrent miscarriages and to assess differences related to cause of infertility.Methods. The outcome from 1220 IVF pregnancies (Group I) was compared with 611 spontaneous pregnancies (Group II) in women with recurrent miscarriages. Subgroup analysis was performed in Group I based on cause of infertility: tubal factor (392 pregnancies); male factor (610 pregnancies); and unexplained infertility (218 pregnancies).Results. The clinical pregnancy loss rate in Group I (14.3%) was significantly lower than that of Group II (25.8%,p<0.001) and this was independent of the cause of infertility. However the timing of pregnancy loss was similar between Groups I and II. The clinical pregnancy loss rate in Group I was similar in different causes of infertility.Conclusions. The clinical pregnancy loss rate following IVF treatment is lower than that of women with unexplained recurrent miscarriages who conceived spontaneously. This difference persists whether the infertility is secondary to tubal factors, male factors, or unexplained cause.

International determination of the total motion of the pole

1961 ◽  
Vol 13 ◽  
pp. 29-41
Author(s):  
Wm. Markowitz
Keyword(s):  
Secular Motion ◽  
The Future

A symposium on the future of the International Latitude Service (I. L. S.) is to be held in Helsinki in July 1960. My report for the symposium consists of two parts. Part I, denoded (Mk I) was published [1] earlier in 1960 under the title “Latitude and Longitude, and the Secular Motion of the Pole”. Part II is the present paper, denoded (Mk II).

Status of the Lick Proper Motion Program

1978 ◽  
Vol 48 ◽  
pp. 387-388
Author(s):  
A. R. Klemola
Keyword(s):  
Proper Motion ◽  
The Future

Second-epoch photographs have now been obtained for nearly 850 of the 1246 fields of the proper motion program with centers at declination -20° and northwards. For the sky at 0° and northward only 130 fields remain to be taken in the next year or two. The 270 southern fields with centers at -5° to -20° remain for the future.

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