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From storage to delivery: Sperm volume and number of spermatozoa inside storage organs and ejaculates in males of Timogenes elegans (Scorpiones: Bothriuridae)
(American Arachnological Society, 2018-08)
Sperm competition influences the evolution of many reproductive traits such as gonads, sperm or genitalia. Many sperm competition analyses concentrate in testes and ejaculates. Among arachnids, scorpions constitute an ...
Patterns of sperm transfer behavior in a pholcid spider with two distinct copulatory phases
(Springer New York LLC, 2018-11)
Sexual selection is the responsible force for the evolution and maintenance of genital diversity and function. This is the case for example, of genital movements performed by males during mating and copulation duration. ...
An investigation into the male reproductive system of two freshwater crabs from the Amazon: is there a sperm plug or packet formation?
(2018-07-04)
The male reproductive system of Amazon freshwater crabs Sylviocarcinus pictus and Dilocarcinus pagei were described and compared in terms of anatomy and histochemistry In addition, sperm transfer experiments of D. pagei ...
Artificial insemination unveils a first-male fertilization advantage in the guppy
(Academic Press Ltd - Elsevier Science Ltd, 2017-09)
Several factors are involved in determining the outcome of sperm competition. In addition to sperm number, sperm quality and male phenotype, insemination order is often associated with skewed paternity share. Patterns of ...
Improved bovine in vitro embryo production with sexed and unsexed sperm selected by chemotaxis
(Elsevier Science Inc, 2018-12)
Assisted reproductive techniques (ART) have been widely used in farm animals in the last decades. Sexed cryopreserved spermatozoa, ovum pick up, in vitro embryo production and transfer constitute the ART that have ...
Different sperm allocation strategies in two populations of the semiterrestrial crab Neohelice granulata (Brachyura, Grapsoidea, Varunidae)
(Wiley Blackwell Publishing, Inc, 2016-08)
Sperm reserves are costly to produce and so the development of different sperm allocation strategies may be advantageous. Knowledge of sperm allocation strategies is important from an evolutionary perspective because they ...
A hypothesis about the origin of sperm storage in the Eubrachyura, the effects of seminal receptacle structure on mating strategies and the evolution of crab diversity: How did a race to be first become a race to be last?
(Elsevier Gmbh, 2011-10)
The origins and evolution of sperm storage in Brachyura are enigmatic: sperm is either stored in seminal receptacles, accessible via the vulvae on the sixth thoracic sternite, or in spermathecae at the border between the ...
Functional morphology of the reproductive system and sperm transfer in Stenopus hispidus (Crustacea: Decapoda: Stenopodidea), and their relation to the mating system
(Wiley-Blackwell, 2014-12-01)
The morphology of the reproductive system of a stenopodidean decapod is described here for the first time, with an interpretation of the sperm transfer process. Pairs of adults of Stenopus hispidus were maintained under ...
Boar seminal plasma exosomes: Effect on sperm function and protein identification by sequencing
(Elsevier Science Inc, 2013-04)
Mammalian seminal plasma contains membranous vesicles (exosomes), with a high content of cholesterol and sphingomyelin and a complex protein composition. Their physiological role is uncertain because sperm stabilization ...