Sperm Sizer: a program to semi-automate the measurement of sperm length

2021 ◽  
Vol 75 (5) ◽  
Author(s):  
Callum S. McDiarmid ◽  
Roger Li ◽  
Ariel F. Kahrl ◽  
Melissah Rowe ◽  
Simon C. Griffith
Keyword(s):  
Sperm Length

scholarly journals Evolution of testicular architecture in the Drosophilidae: A role for sperm length

2008 ◽  
Vol 8 (1) ◽  
pp. 143 ◽  
Author(s):  
Lukas Schärer ◽  
Jean-Luc Da Lage ◽  
Dominique Joly
Keyword(s):  
Sperm Length

scholarly journals Morphometric Characteristics of the Spermatozoa of Blue Fox (Alopex lagopus) and Silver Fox (Vulpes vulpes)

Animals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1927
Author(s):  
Katarzyna Andraszek ◽  
Dorota Banaszewska ◽  
Olga Szeleszczuk ◽  
Marta Kuchta-Gładysz ◽  
Anna Grzesiakowska
Keyword(s):  
Vulpes Vulpes ◽  
Tail Length ◽  
Head Length ◽  
Head Width ◽  
Sperm Length ◽  
Alopex Lagopus ◽  
Silver Fox ◽  
Shape Indices ◽  
Length Width ◽  
Blue Fox

The results presented in this study are the first such extensive characterization of the sperm morphometry of the blue fox (Alopex lagopus) and silver fox (Vulpes vulpes), as representatives of the family Canidae. Canine spermatozoa, especially the sperm of farmed foxes, are not often described in studies on reproduction. The aim of the study was a detailed comparison of the morphometric dimensions and shape of the sperm of two fox species: silver fox and blue fox. Semen collected from 10 silver foxes and 10 blue foxes was used for the study. The specimens were stained with silver nitrate. Measurements were performed of the length, width, perimeter, and area of the head; the area of the acrosome and its coverage; the length of the midpiece and its coverage; the length of the tail; and the length of the end piece of the tail. In addition, four head shape indices were calculated: ellipticity, elongation, roughness and regularity. The following values for the morphometric parameters and shape indices were obtained for blue fox and silver fox, respectively: head length—6.72 µm and 6.33 µm; head width—4.54.µm and 4.21 µm; head perimeter—18.11 µm and 17.37 µm; head area—21.94 µm2 and 21.11 µm2; acrosome area—11.50 µm2 and 10.92 µm2; midpiece length—12.85 µm and 12.79 µm; tail end piece length—3.44 µm and 3.28 µm; tail length—65.23 µm and 65.09 µm; acrosome coverage—52.43% and 52.83%; midpiece coverage—19.71% and 19.65%; sperm length—71.95 µm and 71.42 µm; ellipticity—1.49 and 1.52; elongation—0.19 and 0.20; roughness—0.84 and 1.88; regularity—1.09 and 0.99. The significance of differences between species was verified by Tukey’s test at p ≤ 0.05. Statistically significant differences between species were found for the following parameters: head length, width, perimeter and area; acrosome area; tail, end piece, and total sperm length; roughness and regularity. The differences in the size and shape of sperm can be used to establish reference patterns for fox sperm enabling more accurate species identification.

Heritability of sperm length in the bumblebee Bombus terrestris

Genetica ◽  
2006 ◽  
Vol 127 (1-3) ◽  
pp. 11-23 ◽  
Author(s):  
Boris Baer ◽  
Gerdien de Jong ◽  
Regula Schmid-Hempel ◽  
Paul Schmid-Hempel ◽  
Jens T. Høeg ◽  
...  
Keyword(s):  
Bombus Terrestris ◽  
Sperm Length

138 Associations of sperm head morphometrics with quality parameters of frozen-thawed ram semen

2020 ◽  
Vol 32 (2) ◽  
pp. 195
Author(s):  
J. Navaranjan ◽  
J. Szymanowicz ◽  
M. Murawski ◽  
T. Schwarz ◽  
P. M. Bartlewski
Keyword(s):  
Alkaline Phosphatase ◽  
Survival Time ◽  
Aspartate Aminotransferase ◽  
Sperm Quality ◽  
Sperm Head ◽  
Head Length ◽  
Cell Membrane Permeability ◽  
Sperm Length ◽  
Progressive Motility ◽  
Synthetic Line

Current methods of mammalian semen evaluation focus on determining spermatozoa motility, concentration, mitochondrial status, and nucleus or chromatin structure integrity, quantifying their ability to bind to ova or measuring seminal plasma content of various biochemical markers. However, there is a paucity of studies that address relationships between sperm head morphometry (the external shape and dimensions of the sperm) and fertilising ability. Sperm head morphometrics are influenced by many molecular and biochemical factors such as genetics, DNA or protein condensation, and cell membrane permeability, all of which can affect semen viability. The objective of this experimental work was to determine quantitative correlations between sperm head dimensions and various indices of sperm quality in frozen-thawed ram semen. Ejaculates were collected from 16 clinically healthy rams (4 Polish Lowland (PON), 4 Olkuska, 5 synthetic line BCP (Berrichon du Cher×Charolais×PON/Polish Merino), and 3 synthetic line SCP (Suffolk×Charolais×PON/Polish Merino) aged 4-12 years) into an artificial vagina in the middle portion of the breeding season. Ejaculates from each ram were divided into two equal portions, diluted with a commercial semen extender prepared in deionised water or nanowater (water declusterised using cold plasma treatment) to a final concentration of 400×106 spermatozoamL−1, and frozen in 0.25-mL plastic straws. After 6 months of being cryogenically preserved, semen samples were thawed and used for the preparation of smears stained with eosin or SpermBlue. Images of the samples containing at least 100 spermatozoa were taken under 200× magnification and used for determination of sperm head morphology with the image analytical software Image Pro Plus (Media Cybernetics Inc.). Sperm progressive motility and survival time, as well as extender concentrations of alkaline phosphatase and aspartate aminotransferase, were measured. Finally, 128 BCP ewes were inseminated laparoscopically with the ram semen and fertility parameters were recorded. The present data were analysed using a multivariate analysis of variance in SAS (SAS Institute Inc.) and Spearman correlation tests. There were no significant effects or interactions of breed, staining method, or extender diluent on sperm head dimensions (head length, width, area, perimeter, and roundness). The mean head length was negatively correlated (P<0.05) with the percentages of spermatozoa with vacuolated, detached, or amorphous heads or small acrosomes; thick and thin midpiece defects, distal droplet, broken tail plus distal droplet, short tail plus distal droplet, and thick midpiece plus proximal droplet; and sperm progressive motility. In addition, sperm head roundness was negatively correlated with the proportion of spermatozoa with coiled tails. There were no correlations of sperm head dimensions with survival time, alkaline phosphatase and aspartate aminotransferase concentrations, or conception and pregnancy rates of artificially inseminated ewes. Sperm length and roundness (but no other measurements) were significantly correlated with segmental sperm defects and motility that may impinge the fertilising ability of frozen-thawed ram semen.

Brain size evolution in anurans: a review

2019 ◽  
Vol 69 (3) ◽  
pp. 265-279 ◽  
Author(s):  
Chun Lan Mai ◽  
Wen Bo Liao
Keyword(s):  
Sexual Selection ◽  
Life History ◽  
Life History Traits ◽  
Developmental Stages ◽  
Brain Size ◽  
Ecological Factors ◽  
Brain Regions ◽  
Sperm Length ◽  
Testis Size ◽  
Size Evolution

Abstract Selection pressure is an important force in shaping the evolution of vertebrate brain size among populations within species as well as between species. The evolution of brain size is tightly linked to natural and sexual selection, and life-history traits. In particular, increased environmental stress, intensity of sexual selection, and slower life history usually result in enlarged brains. However, although previous studies have addressed the causes of brain size evolution, no systematic reviews have been conducted to explain brain size in anurans. Here, we review whether brain size evolution supports the cognitive buffer hypothesis (CBH), the expensive tissue hypothesis (ETH), or the developmental cost hypothesis (DCH) by analyzing the intraspecific and/or interspecific patterns in brain size and brain regions (i.e., olfactory nerves, olfactory bulbs, telencephalon, optic tectum, and cerebellum) associated with ecological factors (habitat, diet and predator risk), sexual selection intensity, life-history traits (age at sexual maturity, mean age, longevity, clutch size and egg size, testis size and sperm length), and other energetic organs. Our findings suggest that brain size evolution in anurans supports the CBH, ETH or DCH. We also suggest future directions for studying the relationships between brain size evolution and crypsis (i.e., ordinary mucous glands in the skin), and food alteration in different developmental stages.

Reproductive context of extremely short sperm in the parasitic wasp Cotesia congregata (Hymenoptera: Braconidae)

2020 ◽  
Vol 131 (2) ◽  
pp. 384-395
Author(s):  
Justin P Bredlau ◽  
Ahmed M El-Sabrout ◽  
Christophe Bressac
Keyword(s):  
Parasitic Wasp ◽  
Sperm Concentration ◽  
Pupal Stage ◽  
Interspecific Variation ◽  
Reproductive Organs ◽  
Sperm Length ◽  
Small Female ◽  
Cotesia Congregata ◽  
Sperm Counts ◽  
Reproductive Life

Abstract Among adaptive traits under sexual selection, the length of spermatozoa shows high interspecific variation. In insects, extremes exist for both short and long sperm. The spermatozoa of the endoparasitic wasp Cotesia congregata (Say) are the shortest flagellated sperm described in animals, 6.6 µm in length. By comparison, the sperm of Drosophila bifurca are almost 6000 times longer. Thus, C. congregata has the potential to shed light on the selection pressures that drive variation in sperm length in relation to their production and use. The reproductive organs, sperm counts, controlled oviposition and sex ratios were investigated. The testes showed stratified differentiation stages of spermatogenesis, and sperm counts revealed continuous spermatogenesis in the late pupal stage. The small female spermatheca stored ~1000 sperm, resulting in an extremely high sperm concentration. The number of progeny per brood decreased over time until depletion of eggs. Females produced up to 370 daughters, corresponding to the effective use of 34% of the average sperm stock. Haploid males made up a greater proportion of broods in later parasitisms. Sperm miniaturization may be an adaptation to transfer increased quantities for the entire reproductive life of females in the absence of sperm competition but in the reduced space offered by the spermatheca.

scholarly journals Inbreeding depresses sperm competitiveness, but not fertilization or mating success in male Tribolium castaneum

2010 ◽  
Vol 277 (1699) ◽  
pp. 3483-3491 ◽  
Author(s):  
Łukasz Michalczyk ◽  
Oliver Y. Martin ◽  
Anna L. Millard ◽  
Brent C. Emerson ◽  
Matthew J. G. Gage
Keyword(s):  
Sperm Competition ◽  
Inbreeding Depression ◽  
Tribolium Castaneum ◽  
Mating Behaviour ◽  
Fertilization Success ◽  
Heterozygote Advantage ◽  
Length Variation ◽  
Sperm Length ◽  
Mating Pattern ◽  
Normal Fertilization

As populations decline to levels where reproduction among close genetic relatives becomes more probable, subsequent increases in homozygous recessive deleterious expression and/or loss of heterozygote advantage can lead to inbreeding depression. Here, we measure how inbreeding across replicate lines of the flour beetle Tribolium castaneum impacts on male reproductive fitness in the absence or presence of male–male competition. Effects on male evolution from mating pattern were removed by enforcing monogamous mating throughout. After inbreeding across eight generations, we found that male fertility in the absence of competition was unaffected. However, we found significant inbreeding depression of sperm competitiveness: non-inbred males won 57 per cent of fertilizations in competition, while inbred equivalents only sired 42 per cent. We also found that the P 2 ‘offence’ role in sperm competition was significantly more depressed under inbreeding than sperm ‘defence’ (P 1 ). Mating behaviour did not explain these differences, and there was no difference in the viability of offspring sired by inbred or non-inbred males. Sperm length variation was significantly greater in the ejaculates of inbred males. Our results show that male ability to achieve normal fertilization success was not depressed under strong inbreeding, but that inbreeding depression in these traits occurred when conditions of sperm competition were generated.

scholarly journals Patterns of sperm damage in Chernobyl passerine birds suggest a trade-off between sperm length and integrity

2013 ◽  
Vol 9 (5) ◽  
pp. 20130530 ◽  
Author(s):  
Ignacio G. Hermosell ◽  
Terje Laskemoen ◽  
Melissah Rowe ◽  
Anders P. Møller ◽  
Timothy A. Mousseau ◽  
...  
Keyword(s):  
Sperm Competition ◽  
Acrosome Reaction ◽  
Interspecific Variation ◽  
Passerine Bird ◽  
Sperm Length ◽  
Passerine Birds ◽  
Trade Off ◽  
Sperm Abnormalities ◽  
Trade Offs ◽  
Sperm Competition Risk

Interspecific variation in sperm size is enigmatic, but generally assumed to reflect species-specific trade-offs in selection pressures. Among passerine birds, sperm length varies sevenfold, and sperm competition risk seems to drive the evolution of longer sperm. However, little is known about factors favouring short sperm or constraining the evolution of longer sperm. Here, we report a comparative analysis of sperm head abnormalities among 11 species of passerine bird in Chernobyl, presumably resulting from chronic irradiation following the 1986 accident. Frequencies of sperm abnormalities varied between 15.7 and 77.3% among species, more than fourfold higher than in uncontaminated areas. Nonetheless, species ranked similarly in sperm abnormalities in unpolluted areas as in Chernobyl, pointing to intrinsic factors underlying variation in sperm damage among species. Scanning electron microscopy of abnormal spermatozoa revealed patterns of acrosome damage consistent with premature acrosome reaction. Sperm length, but not sperm competition risk explained variation in sperm damage among species. This suggests that longer spermatozoa are more susceptible to premature acrosome reaction. Therefore, we hypothesize a trade-off between sperm length and sperm integrity affecting sperm evolution in passerine birds.

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