Using X-ray microscopy two morphologically distinct states were observed of the human spermatozoan mitochondria: (i) compact and tightly wrapped around the axoneme, and (ii) morphologically transformed, i.e. with circular areas of high X-ray transmission, either loosely wrapped around the axoneme or distended. The spermatozoa were examined at two stages of their post-ejaculation maturation proc...

to determine the effect of different levels of l-glutamine and glycerol on freezing coated sperm, semen were collected from 4 taleshi rams through artificial vagina contact with a tube containing tris-fructose-egg yolk 15%. ejaculates were pooled, centrifuged and supernatant was removed, then cell fractions were used. samples were split into 9 equal parts and 3 (g3), 5 (g5) or 7% (g7) glycerol ...

Ultrastructural studies of cytoplasmic droplets of the spermatozoa of bulls, rams, rabbits, rats (Bloom & Nicander, 1961) and bats (Fawcett & Ito, 1965) revealed only numerous membranous vesicles and tubules in the matrix of the droplets. These authors agreed that the membranous elements were probably of endoplasmic reticulum and/or Golgi complex origin. The simplicity of the ultrastructure and...

introduction artificial insemination (ai) has only been used as a supplement to natural mating. ai, when used in conjunction with accurate progeny testing schemes, can substantially increase the rate of genetic progress compared with that of natural service. moreover, the use of ai causes the limitation of the transmitted diseases. cervical insemination with frozen-thawed ram semen has not been...

Rabbit spermatozoa were labelled in vivo by injecting a male whith 6 mCi of 2,8-T-adenine. On day 49 after injection, a suspension of spermatozoa from caudae epididymidis and ductus deferentes in saline was prepared. Sperm samples were stored frozen at 5°C, exposed to autolysis for 10 days at + 37° C, and smeared. Smears from freshly obtained sperm were hydrolyzed with HCI iN or extracted with ...

BACKGROUND Sperm cryopreservation is the most effective method to preserve male fertility but this is normally used for motile spermatozoa. Thus, only motile spermatozoa are used for cryopreservation in most reproductive medicine centers worldwide. The immotile spermatozoa from some problematic patients are usually discarded, resulting in a missed opportunity of sterility cryopreservation for f...

Mammalian spermatozoa are coated with a thick glycocalyx that is assembled during sperm development, maturation, and upon contact with seminal fluid. The sperm glycocalyx is critical for sperm survival in the female reproductive tract and is modified during capacitation. The complex interplay among the various glycoconjugates generates numerous signaling motifs that may regulate sperm function ...

Fresh and post-thaw parameters (motility, morphology and viability) of stallion epididymal spermatozoa that have been and have not been exposed to seminal plasma were evaluated, and directly compared to fresh and post-thaw parameters of ejaculated spermatozoa. Six sperm categories of each stallion (n=4) were evaluated for motility, morphology and viability. These categories were fresh ejaculate...