ScratchAndGO
11-02-2014, 08:26 AM
Jack,
I recently collected one of my studs to do a breeding and start freezing some for future use and to sell overseas. When we did the evaluation of the collection we found that 40% of them had cytoplasmic droplets. 60% of the sperm were normal and healthy. He had a count of 620 million with great motility. I am enclosing a article to explain the abnormality. Basically they are a droplet at the base of the sperm head where they have not developed completely in the epididymis. There is a ton of speculation as to why a sperm cell lacks complete maturation but nothing real definitive. Have you heard of this problem? And if so any suggestions as to how to deal with it. When I was breeding Slim(TabXRuby) I ran into this. He had about 80% with droplets on them. Although I was able to get pups from breeding him I missed several key breeding's that I would have liked to have done. I am attaching a pretty informative article that explains it somewhat. I will copy and paste some of the key points and attach a link to the complete article. Thanks very much in advance for your time looing into this.
Have a good one,
Eric
P.S.
The ability to post and get informative responses about complicated & specific issues such as this one makes this site well worth the increase in fees. As the old adage goes... " You get what you pay for "
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/
Cytoplasmic droplets: origin and migration
During normal spermatogenesis, most of the round spermatid's cytoplasm is phagocytosed as ‘residual bodies' by the Sertoli cell at spermiogenesis, and only a small cytoplasmic residue (the ‘cytoplasmic droplet') remains applied to the elongated spermatid after release from the germinal epithelium. A characteristic morphological change to spermatozoa during epididymal transit is the caudal migration of the cytoplasmic droplet away from the neck, behind the head, to the annulus, at the end of the midpiece. This was first reported by Merton25 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib25) for the mouse and subsequently confirmed in other species. The epididymal location of this migration varies among species,26 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib26) but the physiological significance of it, if any, has yet to be defined. The plasma membrane overlying the droplet is contiguous with that of the rest of the cell so that the cytoplasm comes into close circumferential proximity to the outer mitochondrial membranes once the droplet has passed caudally. Whether this migration affects the maturational changes in lipid mobility over the mitochondria27 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib27), 28 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib28) remains to be elucidated.
Another unknown mechanism is how the droplet migrates. The proximal droplets of some ovine testicular spermatozoa begin to move distally during storage in ret testis fluid9 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib9) and the unphysiological stresses of centrifugation cause the neck droplets of caprine and porcine testicular spermatozoa to shift caudally;29 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib29), 30 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib30)hence, perhaps the physical jostling of highly concentrated spermatozoa being moved by epididymal peristalsis could affect the same end result in vivo. Spermatozoa are certainly physically sensitive, they can lose droplets to shearing forces31 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib31) and head-to-head contact induces coalescence of membrane lipids at the site of contact.32 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib32) It could also be that this movement is related to the volume regulation postulated to occur within the lumen (see below), necessarily centred on this organelle, the largest volume of cytoplasm the spermatozoon has. In this scenario, the water efflux that occurs during isovolumetric regulation would occur at the cephalic pole of the droplet and influx of water and osmolytes in the caudal pole, leading to a gradual caudal ‘creeping' of the droplet along the midpiece (Figure 3 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/figure/fig3/)). This speculation requires differential location of the channels mediating such fluid transport on the droplet's membrane. Changes in cytoskeletal proteins may also be involved, possibly responding the continual changes in ionic strength within the droplets.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/bin/aja201097f3.gifFigure 3 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/figure/fig3/)
Schematic representation of the mode of migration of a cytoplasmic droplet along the midpiece within the epididymal lumen. Isovolumetric regulation in response to intraluminal hypertonicity is considered here to involve water efflux at the cephalic pole ...
I recently collected one of my studs to do a breeding and start freezing some for future use and to sell overseas. When we did the evaluation of the collection we found that 40% of them had cytoplasmic droplets. 60% of the sperm were normal and healthy. He had a count of 620 million with great motility. I am enclosing a article to explain the abnormality. Basically they are a droplet at the base of the sperm head where they have not developed completely in the epididymis. There is a ton of speculation as to why a sperm cell lacks complete maturation but nothing real definitive. Have you heard of this problem? And if so any suggestions as to how to deal with it. When I was breeding Slim(TabXRuby) I ran into this. He had about 80% with droplets on them. Although I was able to get pups from breeding him I missed several key breeding's that I would have liked to have done. I am attaching a pretty informative article that explains it somewhat. I will copy and paste some of the key points and attach a link to the complete article. Thanks very much in advance for your time looing into this.
Have a good one,
Eric
P.S.
The ability to post and get informative responses about complicated & specific issues such as this one makes this site well worth the increase in fees. As the old adage goes... " You get what you pay for "
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/
Cytoplasmic droplets: origin and migration
During normal spermatogenesis, most of the round spermatid's cytoplasm is phagocytosed as ‘residual bodies' by the Sertoli cell at spermiogenesis, and only a small cytoplasmic residue (the ‘cytoplasmic droplet') remains applied to the elongated spermatid after release from the germinal epithelium. A characteristic morphological change to spermatozoa during epididymal transit is the caudal migration of the cytoplasmic droplet away from the neck, behind the head, to the annulus, at the end of the midpiece. This was first reported by Merton25 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib25) for the mouse and subsequently confirmed in other species. The epididymal location of this migration varies among species,26 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib26) but the physiological significance of it, if any, has yet to be defined. The plasma membrane overlying the droplet is contiguous with that of the rest of the cell so that the cytoplasm comes into close circumferential proximity to the outer mitochondrial membranes once the droplet has passed caudally. Whether this migration affects the maturational changes in lipid mobility over the mitochondria27 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib27), 28 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib28) remains to be elucidated.
Another unknown mechanism is how the droplet migrates. The proximal droplets of some ovine testicular spermatozoa begin to move distally during storage in ret testis fluid9 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib9) and the unphysiological stresses of centrifugation cause the neck droplets of caprine and porcine testicular spermatozoa to shift caudally;29 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib29), 30 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib30)hence, perhaps the physical jostling of highly concentrated spermatozoa being moved by epididymal peristalsis could affect the same end result in vivo. Spermatozoa are certainly physically sensitive, they can lose droplets to shearing forces31 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib31) and head-to-head contact induces coalescence of membrane lipids at the site of contact.32 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/#bib32) It could also be that this movement is related to the volume regulation postulated to occur within the lumen (see below), necessarily centred on this organelle, the largest volume of cytoplasm the spermatozoon has. In this scenario, the water efflux that occurs during isovolumetric regulation would occur at the cephalic pole of the droplet and influx of water and osmolytes in the caudal pole, leading to a gradual caudal ‘creeping' of the droplet along the midpiece (Figure 3 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/figure/fig3/)). This speculation requires differential location of the channels mediating such fluid transport on the droplet's membrane. Changes in cytoskeletal proteins may also be involved, possibly responding the continual changes in ionic strength within the droplets.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/bin/aja201097f3.gifFigure 3 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3739406/figure/fig3/)
Schematic representation of the mode of migration of a cytoplasmic droplet along the midpiece within the epididymal lumen. Isovolumetric regulation in response to intraluminal hypertonicity is considered here to involve water efflux at the cephalic pole ...