No effect of sperm interactions or egg homogenate on sperm velocity in the blue mussel, Mytilus edulis (Bivalvia: Mytilidae)

We investigated the possible effects of sperm interactions and homogenized eggs on sperm velocity in blue mussels ( Mytilus edulis L., 1758) using computer-assisted sperm analysis. To test whether sperm competition results in an increase in sperm velocity, using seven pairs of males, we compared the mean curvilinear and average path velocities of sperm from two males measured separately with the corresponding values from a mixture of sperm from the same two males. To test whether the presence of eggs results in an increase in sperm velocity, we compared curvilinear and average path velocities from 11 individual males with the corresponding measures from the same 11 sperm samples mixed with aliquots of homogenized eggs. Neither experimental treatment resulted in an increase in sperm velocity. We interpret these results as consistent with the hypothesis that mussel sperm have been selected to immediately begin swimming at an optimal initial velocity that is adaptive for the particular environment in which they are located. Critical factors affecting the evolution of sperm velocity for broadcast spawning, external fertilizers such as M. edulis likely include population density and intraspecific spawning synchronicity. As has been suggested by others, the importance of sperm limitation (i.e., having much less than 100% of eggs being fertilized in the wild) may be as important an evolutionary driving force in broadcast spawning invertebrates as sperm competition is in internally or directly fertilized species.

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Cryptic female preference for genetically unrelated males is mediated by ovarian fluid in the guppy

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.2369 ◽

2011 ◽

Vol 278 (1717) ◽

pp. 2495-2501 ◽

Cited By ~ 110

Author(s):

Clelia Gasparini ◽

Andrea Pilastro

Keyword(s):

Sperm Competition ◽

Computer Assisted ◽

Ovarian Fluid ◽

Embryo Survival ◽

Single Male ◽

Sperm Analysis ◽

Fitness Consequences ◽

The Cost ◽

Unrelated Male

As inbreeding is costly, it has been suggested that polyandry may evolve as a means to reduce the negative fitness consequences of mating with genetically related males. While several studies provide support for this hypothesis, evidence of pure post-copulatory mechanisms capable of biasing paternity towards genetically unrelated males is still lacking; yet these are necessary to support inbreeding avoidance models of polyandry evolution. Here we showed, by artificially inseminating a group of female guppies with an equal number of sperm from related (full-sib) and unrelated males, that sperm competition success of the former was 10 per cent lower, on average, than that of the unrelated male. The paternity bias towards unrelated males was not due to differential embryo survival, as the size of the brood produced by control females, which were artificially inseminated with the sperm of a single male, was not influenced by their relatedness with the male. Finally, we collected ovarian fluid (OF) from virgin females. Using computer-assisted sperm analysis, we found that sperm velocity, a predictor of sperm competition success in the guppy, was significantly lower when measured in a solution containing the OF from a sister as compared with that from an unrelated female. Our results suggest that sperm–OF interaction mediates sperm competition bias towards unrelated mates and highlight the role of post-copulatory mechanisms in reducing the cost of mating with relatives in polyandrous females.

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Female presence influences sperm velocity in the guppy

Biology Letters ◽

10.1098/rsbl.2009.0413 ◽

2009 ◽

Vol 5 (6) ◽

pp. 792-794 ◽

Cited By ~ 41

Author(s):

Clelia Gasparini ◽

Alfredo V. Peretti ◽

Andrea Pilastro

Keyword(s):

Poecilia Reticulata ◽

Sperm Quality ◽

Adaptive Plasticity ◽

Computer Assisted ◽

Sperm Production ◽

Sperm Velocity ◽

Visual Contact ◽

Sperm Analysis ◽

Mating Opportunities ◽

Female Presence

As sperm production is costly, males are expected to strategically allocate resources to sperm production according to mating opportunities. While sperm number adjustments have been reported in several taxa, only a few studies investigated whether sperm quality shows adaptive plasticity as well. We tested this prediction in the guppy, Poecilia reticulata . A total of 46 males were initially stripped of all retrievable sperm before being randomly allocated to one of two treatments simulating different levels of mating opportunities (visual contact with females or female deprived). After 3 days, males were stripped and sperm velocity was assayed using Computer Assisted Sperm Analysis. Males in the presence of females produced significantly faster sperm than their counterparts. Implications for the evolution of this ejaculate plasticity in the light of results of sperm competition studies are discussed.

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Antibiotics and oxygen availability affect the short-term storage of spermatozoa from the critically endangered booroolong frog, Litoria booroolongensis

Reproduction Fertility and Development ◽

10.1071/rd14062 ◽

2015 ◽

Vol 27 (8) ◽

pp. 1147 ◽

Cited By ~ 11

Author(s):

Aimee J. Silla ◽

Leesa M. Keogh ◽

Phillip G. Byrne

Keyword(s):

Sperm Motility ◽

Storage Period ◽

Oxygen Availability ◽

Critically Endangered ◽

Computer Assisted ◽

Sperm Velocity ◽

Sperm Analysis ◽

Sperm Longevity ◽

Sperm Suspension ◽

Experimental Treatments

Sperm-storage technologies aim to extend sperm longevity and increase the time available to achieve artificial fertilisation. The aim of the present study was to quantify the effects of antibiotic supplementation (4 mg mL–1 gentamicin) and altered gaseous storage environment (100%, 20% and 0% O2) on sperm longevity in the critically endangered booroolong frog, Litoria booroolongensis. A split-sample experimental design was adopted, whereby each sperm suspension (n = 10) was evenly divided among six experimental treatments (100% O2 with antibiotic, 20% O2 with antibiotic, 0% O2 with antibiotic, 100% O2 without antibiotic, 20% O2 without antibiotic, 0% O2 without antibiotic). Sperm suspensions were refrigerated at 5°C for the duration of the 21-day storage period. Percentage sperm motility and sperm velocity were quantified every 3 days using a computer-assisted sperm analysis system. Treatments aerated with either 100% or 20% oxygen, without the addition of the antibiotic gentamicin, consistently exhibited the highest percentage sperm motility. On Day 21 of storage, sperm suspensions in these two treatments (100% O2 without antibiotic, 20% O2 without antibiotic) maintained 61.3% and 52.0% sperm motility, respectively, whereas all remaining experimental treatments exhibited <30% sperm motility. Sperm velocity did not differ significantly among storage treatments, at any of the sampling periods, with the exception of day 21. Overall, the results from this study indicate that increased oxygen availability is beneficial to sperm longevity, but that gentamicin inhibits sperm motility in L. booroolongensis.

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380 Factors Affecting Computer-Assisted Sperm Analysis (CASA) Measurements for Porcine Spermatozoa.

Journal of Animal Science ◽

10.1093/jas/sky073.377 ◽

2018 ◽

Vol 96 (suppl_2) ◽

pp. 204-205

Author(s):

D Zaritskiy ◽

W L Flowers

Keyword(s):

Computer Assisted ◽

Factors Affecting ◽

Sperm Analysis ◽

Computer Assisted Sperm Analysis ◽

Porcine Spermatozoa

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Evaluation of blue mussel Mytilus edulis as vector for viral hemorrhagic septicemia virus (VHSV)

Diseases of Aquatic Organisms ◽

10.3354/dao03180 ◽

2017 ◽

Vol 126 (3) ◽

pp. 239-246 ◽

Cited By ~ 1

Author(s):

KI Kim ◽

YC Kim ◽

WJ Kwon ◽

HD Jeong

Keyword(s):

Mytilus Edulis ◽

Blue Mussel ◽

Viral Hemorrhagic Septicemia Virus ◽

Viral Hemorrhagic Septicemia

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Сравнительная оценка спермопродукции чистопородных и гибридных хряков-производителей

Аграрная Россия ◽

10.30906/1999-5636-2017-6-2-6 ◽

2017 ◽

pp. 2-6

Author(s):

Байлар Садраддинович Иолчиев ◽

Анна Валиевна Таджиева ◽

Павел Михайлович Кленовицкий ◽

Вугар Алиевич Багиров ◽

Александр Алексеевич Никишов ◽

...

Keyword(s):

Computer Assisted ◽

Sperm Analysis ◽

Computer Assisted Sperm Analysis

Практической частью репродуктивной технологии является прогноз и оценка фертильности самцов. Существующие методы оценки семени не дают достаточно корректного прогноза результатов осеменения и, следовательно, репродуктивного потенциала того или иного производителя. В работе приведены данные комплексной оценки биологической полноценности семени чистопородных и гибридных хряков-производителей с использованием компьютерной технологии CASA (computer-assisted sperm analysis). Оценивали активность сперматозоидов в образцах классическим способом (микроскопирование) и с помощью компьютерной технологии, программа «Зоосперм 1.0». Исследования проводили в 2014 – 2015 гг. в Лаборатории репродуктивной криобиологии животных (Россия). Объектом исследования служила сперма чистопородных и гибридных хряков-производителей, разводимых в разных регионах Российской Федерации: крупная белая (n = 24), дюрок (n = 28), ландрас (n = 18), пьетрен (n = 8), гибридные (n = 6). Установлено, что высокими репродуктивными качествами отличаются хряки-производители породы ландрас и гибридов, от них в среднем за эякулят получено 290,2 и 290,6 мл спермы соответственно; наименьшими — хряки-производители породы пьетрен (270 мл). Частота встречаемости сперматозоидов с аномальной морфологией высокая у хряков-производителей породы дюрок (12 %) и пьетрен (15 %). Частота встречаемости аномалии в разных сегментах сперматозоидов зависит от индивидуальной особенности хряков-производителей. У одних производителей наиболее часто встречаются морфологические отклонения головки, например, у хряка породы ландрас оно составило 58,60 %, у других часто встречались отклонения от нормы в строении жгутика (12,1 – 29,3 %). Использование компьютерной технологии при оценке биологической полноценности сперматозоидов хряков-производителей является наиболее точным и информативным.

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Differential Segregation Patterns of Sperm Mitochondria in Embryos of the Blue Mussel (Mytilus edulis)

Genetics ◽

10.1093/genetics/166.2.883 ◽

2004 ◽

Vol 166 (2) ◽

pp. 883-894

Author(s):

Liqin Cao ◽

Ellen Kenchington ◽

Eleftherios Zouros

Keyword(s):

Mitochondrial Dna ◽

Mytilus Edulis ◽

Blue Mussel ◽

Uniparental Inheritance ◽

Male Gonad ◽

Doubly Uniparental Inheritance ◽

Organelle Genomes ◽

Somatic Tissues ◽

Tight Linkage ◽

Mitotracker Green

Abstract In Mytilus, females carry predominantly maternal mitochondrial DNA (mtDNA) but males carry maternal mtDNA in their somatic tissues and paternal mtDNA in their gonads. This phenomenon, known as doubly uniparental inheritance (DUI) of mtDNA, presents a major departure from the uniparental transmission of organelle genomes. Eggs of Mytilus edulis from females that produce exclusively daughters and from females that produce mostly sons were fertilized with sperm stained with MitoTracker Green FM, allowing observation of sperm mitochondria in the embryo by epifluorescent and confocal microscopy. In embryos from females that produce only daughters, sperm mitochondria are randomly dispersed among blastomeres. In embryos from females that produce mostly sons, sperm mitochondria tend to aggregate and end up in one blastomere in the two- and four-cell stages. We postulate that the aggregate eventually ends up in the first germ cells, thus accounting for the presence of paternal mtDNA in the male gonad. This is the first evidence for different behaviors of sperm mitochondria in developing embryos that may explain the tight linkage between gender and inheritance of paternal mitochondrial DNA in species with DUI.

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Post-Thaw Sperm Quality and Functionality in the Autochthonous Pig Breed Gochu Asturcelta

Animals ◽

10.3390/ani11071885 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1885

Author(s):

José Néstor Caamaño ◽

Carolina Tamargo ◽

Inmaculada Parrilla ◽

Felipe Martínez-Pastor ◽

Lorena Padilla ◽

...

Keyword(s):

Genetic Resource ◽

Sperm Quality ◽

Genetic Material ◽

Mitochondrial Activity ◽

Computer Assisted ◽

Kinematic Parameters ◽

Linear Mixed Effects ◽

Sperm Analysis ◽

Computer Assisted Sperm Analysis ◽

Analysis System

Genetic resource banks (GRB) preserve the genetic material of endangered, valuable individuals or genetically relevant breeds. Semen cryopreservation is a crucial technique to reach these goals. Thus, we aimed to assess the sperm parameters of semen doses from the native pig breed Gochu Asturcelta stored at the GRB of Principado de Asturias (GRB-PA, Gijón, Spain), focusing on intrinsic and extrinsic (boar, season) factors. Two straws per boar (n = 18, 8–71 months of age) were thawed, pooled, and assessed after 30 and 150 min at 37 °C by CASA (computer-assisted sperm analysis system; motility and kinematic parameters) and flow cytometry (viability, acrosomal status, mitochondrial activity, apoptosis, reactive oxygen species, and chromatin status). The effects of age, incubation, and season on post-thawing quality were determined using linear mixed-effects models. Parameters were on the range for commercial boar breeds, with chromatin status (SCSA: fragmentation and immaturity) being excellent. Incubation decreased sperm quality and functionality. The boar age did not have a significant effect (p > 0.05), but the between-boar variability was significant (p < 0.001). The season significantly affected many parameters (motility, kinematics, viability, acrosomal status, mitochondrial activity), especially after 150 min of incubation. In general, samples collected in spring and summer showed higher quality post-thawing, the lowest in winter. In conclusion, the sperm doses from the Gochu Asturcelta breed stored at the GRB-PA showed excellent chromatin status and acceptable characteristics after thawing. Therefore, boar and seasonal variability in this autochthonous breed could be relevant for cryobank management.

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