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Current sperm competition determines sperm allocation in a Tephritid Fruit Fly
(Wiley Blackwell Publishing, Inc, 2015-05)
Sperm competition (SC) occurs when the sperm of two or more males compete for the same set of ova. Theoretical models and experimental observations indicate that the presence of rival males causes focal males to adjust ...
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 ...
Sperm allocation and cost of mating in a tropical tephritid fruit fly.
(Journal insect physiology, 2006)
Isolate((R)) and Optiprep((R)) minigradients as alternatives for sperm selection in bovine in vitro embryo production
(Agricultural Inst Canada, 2014-03-01)
The objective of this study was to evaluate alternatives in small volumes to conventional gradient of Percoll((R)) on semen quality, in vitro embryo production, sex ratio and embryo survival after vitrification. Thawed ...
Ejaculate allocation in Brachyura: What do males of Metacarcinus edwardsii respond to?
(2018)
In polygynous species, the sperm economy hypothesis predicts that males can adjust the amount of their ejaculate during copulation in response to (1) individual traits of females according to potential female fecundity, ...
Testes Mass, but Not Sperm Length, Increases with Higher Levels of Polyandry in an Ancient Sex Model
(Public Library of Science, 2014-04)
There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition. ...
Competitive males have higher quality sperm in a monogamous social bee
(BioMed Central, 2016)
Abstract
Background
Reproductive success is determined by the interplay between mating and fertilization success. In social insect species with male-biased sex ratios and ...
Effect of Punica granatum (pomegranate) on sperm production in male rats treated with lead acetate.
(Taylor and Francis, 2011)
The present study was designed to determine whether the treatment with an ethanolic extract of pomegranate (EEP) (Punica granatum) can be useful for the treatment of the deleterious effect of lead acetate (LA) administration ...
Decreased Sperm Motility in Rats Orally Exposed to Single or Mixed Pesticides
(Taylor & Francis Inc, 2010-01-01)
The Brazilian Agency of Sanitary Vigilance (ANVISA) conducted a study that demonstrated the presence of residues of several pesticides in fresh fruits and vegetables that were available for purchase by the general populace. ...