Mean values of TV and SVL for mature specimens with few spermatozoids
did not differ significantly from the values corresponding to mature males in any month of both years (Mann-Whitney U test with Bonferroni adjustment; p> 0.0083, in all cases).
Chemotaxis of bracken spermatozoids
: the role of bimalate ions.
were extracted from the vas deferens sections by pinching one end with splinter forceps and using another splinter forceps, from which the serrations had been completely eliminated leaving a smooth surface, to squeeze the duct fragment and extract the spermatozoids
The prostate is a secretory gland surrounding the urethra at the base of the bladder producing the seminal fluid providing nutrients, ions and enzymes necessary for the survival of the spermatozoids
during their journey through the female reproductive tract.
(190) In fact, the flagella of moss and fern spermatozoids
as well as the cilia of Ginkgo sperm (See Ref.
A group of 10 female rats (250-300 g) were mated and pregnancy assessed by daily vaginal smears revealing spermatozoids
presence the day 1 of pregnancy.
Sperm concentration was determined by direct counting of spermatozoids
in a Neubauer chamber, by diluting a sample of 20 [micro]L into 2 mL of distilled water, obtaining a final dilution of 1:200, being the result presented in mm3.
ignitus, Ellychnia corrusca (Linnaeus) (Coleoptera: Lampyridae), Drosophila melanogaster (Meigen) (Diptera: Drosophilidae) and Pieris napi (Linnaeus) (Lepidoptera: Pieridae), possibly due to secretions transferred with the spermatozoids
by males (CHAPMAN et al., 2003; CIVETTA, 2003; ROONEY; LEWIS, 2002; WEDELL; KARLSSON, 2003) or due to endocrine influence (DAVEY, 2007).
The presence of spermatozoids
was considered indicative of pregnancy, associated with the diagnosis of the estrous phase of the estral cycle.
Since 1992, flow cytometry is used to differentiate between X and Y spermatozoids
according to DNA content.
globosus seems to have no relationship to chromosomal evolution of this species, but reflects a mechanisms which guarantees that great quantities of spermatozoids
are simultaneously differentiated at the moment of reproduction.
Ultrastructure of mature spermatozoids
in the fern Asplenium onopteris L.