TY - JOUR
T1 - Nerve growth factor-β effects on post-thaw bull semen quality
T2 - Effects of nerve growth factor-β added to extenders for cryopreservation of electro-ejaculated and epididymal bull semen
AU - Stewart, Jamie L.
AU - Canisso, Igor F.
AU - Podico, Giorgia
AU - Kaplan, Claire
AU - Garrett, Edgar F.
AU - Shike, Daniel W.
AU - Henley, Parker
AU - Lima, Fabio S.
N1 - Funding Information:
The authors thank the staff at the University of Illinois Beef Barn and clinical year veterinary students for providing assistance during field sample collection. We also thank Som Nanjappa in the Pathobiology Department at the University of Illinois College of Veterinary Medicine for his invaluable assistance with preparing the flow cytometer for semen analyses. This research was supported with funds provided by the Department of Veterinary Clinical Medicine, College of Veterinary Medicine , the University of Illinois at Urbana-Champaign as startup funds for Dr. Fabio Lima.
Funding Information:
The authors thank the staff at the University of Illinois Beef Barn and clinical year veterinary students for providing assistance during field sample collection. We also thank Som Nanjappa in the Pathobiology Department at the University of Illinois College of Veterinary Medicine for his invaluable assistance with preparing the flow cytometer for semen analyses. This research was supported with funds provided by the Department of Veterinary Clinical Medicine, College of Veterinary Medicine, the University of Illinois at Urbana-Champaign as startup funds for Dr. Fabio Lima.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/8
Y1 - 2019/8
N2 - Nerve growth factor-β (NGF) is a seminal plasma protein associated with improved sperm membrane integrity and motility in mammalian species. The objective of this study was to compare post-thaw semen quality from both ejaculated and pididymal-collected bull sperm incubated with purified NGF prior to cryopreservation. Semen was obtained from Angus × Simmental crossbred bulls (n = 10) collected by electroejaculation, followed by castration and epididymal sperm collections 3 days later. Semen samples were incubated with extender having 0 ng/mL (CONT), 0.5 ng/mL (LOW), 5 ng/mL (MED), or 50 ng/mL (HIGH) of purified NGF prior to cryopreservation. Sperm motility was assessed in each sample prior to treatment and cryopreservation and at post-thaw. Flow cytometry was used for post-thaw assessment of sperm viability (SYBR-14/PI), acrosome integrity (FITC-PNA/PI), and chromatin stability (acridine orange). Values for post-thaw sperm motility and velocity variables were decreased, while linearity was increased in samples of the HIGH compared with CONT group (P < 0.01), but there were no differences in epididymal samples (P> 0.05). Samples from the HIGH group also had a lesser amplitude of lateral head displacement at 2.5 and 3 h post-thaw (P < 0.01). Post-thaw sperm viability, acrosome integrity, and DNA fragmentation index were not affected by NGF treatment in either ejaculated or epididymal sperm (P> 0.05). In conclusion, supplementation of freezing extender with NGF had minimal effects on post-thaw sperm quality in bulls. Results indicate NGF may have a function in preventing premature sperm hyperactivation in ejaculated, but not epididymal-collected spermatozoa. Fertility studies, both in vitro and in vivo, are warranted to ascertain the relevancy of these findings.
AB - Nerve growth factor-β (NGF) is a seminal plasma protein associated with improved sperm membrane integrity and motility in mammalian species. The objective of this study was to compare post-thaw semen quality from both ejaculated and pididymal-collected bull sperm incubated with purified NGF prior to cryopreservation. Semen was obtained from Angus × Simmental crossbred bulls (n = 10) collected by electroejaculation, followed by castration and epididymal sperm collections 3 days later. Semen samples were incubated with extender having 0 ng/mL (CONT), 0.5 ng/mL (LOW), 5 ng/mL (MED), or 50 ng/mL (HIGH) of purified NGF prior to cryopreservation. Sperm motility was assessed in each sample prior to treatment and cryopreservation and at post-thaw. Flow cytometry was used for post-thaw assessment of sperm viability (SYBR-14/PI), acrosome integrity (FITC-PNA/PI), and chromatin stability (acridine orange). Values for post-thaw sperm motility and velocity variables were decreased, while linearity was increased in samples of the HIGH compared with CONT group (P < 0.01), but there were no differences in epididymal samples (P> 0.05). Samples from the HIGH group also had a lesser amplitude of lateral head displacement at 2.5 and 3 h post-thaw (P < 0.01). Post-thaw sperm viability, acrosome integrity, and DNA fragmentation index were not affected by NGF treatment in either ejaculated or epididymal sperm (P> 0.05). In conclusion, supplementation of freezing extender with NGF had minimal effects on post-thaw sperm quality in bulls. Results indicate NGF may have a function in preventing premature sperm hyperactivation in ejaculated, but not epididymal-collected spermatozoa. Fertility studies, both in vitro and in vivo, are warranted to ascertain the relevancy of these findings.
KW - Bovine
KW - Flow cytometry
KW - Motility
KW - Nerve growth factor-beta
KW - Spermatozoa
UR - http://www.scopus.com/inward/record.url?scp=85067203943&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85067203943&partnerID=8YFLogxK
U2 - 10.1016/j.anireprosci.2019.06.010
DO - 10.1016/j.anireprosci.2019.06.010
M3 - Article
C2 - 31204090
AN - SCOPUS:85067203943
VL - 207
SP - 107
EP - 117
JO - Animal Reproduction Science
JF - Animal Reproduction Science
SN - 0378-4320
ER -