Assessment of in vitro sperm characteristics in relation to fertility in dairy bulls.
The performance of frozen-thawed spermatozoa from 10 Holstein bulls in a range of in vitro diagnostic tests and the relationship with adjusted in vivo fertility data was determined. The tests included an assessment of motility (subjective and computer-assisted), morphology, concentration, viability, acrosomal and chromatin integrity conducted immediately post-thaw and after swim-up, in conjunction with membrane status (CTC staining) and migration in an artificial cervical mucus. Adjusted in vivo fertility correlated with subjectively assessed post-thaw motility (r=0.672, p=0.033), post-thaw straight-line velocity (r=0.636, p=0.048), post-thaw sperm morphology (r=-0.762, p=0.010), post-thaw sperm viability (r=0.635, p=0.048), the concentration of spermatozoa after swim-up (r=0.649, p=0.042), sperm morphology after swim-up (r=-0.687, p=0.028), the number of spermatozoa migrating 10mm into artificial cervical mucus (r=0.632, p=0.050) and the distance migrated by the vanguard spermatozoon in artificial mucus (r=0.701, p=0.024). A stepwise regression analysis identified tests which, when combined, produced models with a strong correlation (R(2)>0.9) to fertility.
Gillan
Lindsay
L
Centre for Advanced Technologies in Animal Genetics and Reproduction, Faculty of Veterinary Science, The University of Sydney, NSW, Australia. lindsay.gillan@sydneyivf.com
Kroetsch
Tom
T
Maxwell
W M Chis
WM
Evans
Gareth
G
D000177:Acrosome / Q000502:physiology; D000818:Animals; D002417:Cattle / Q000502:physiology*; D002843:Chromatin / Q000502:physiology; D015925:Cryopreservation / Q000662:veterinary*; D003612:Dairying; D005298:Fertility / Q000502:physiology*; D008297:Male; D012044:Regression Analysis; D012662:Semen Preservation / Q000662:veterinary*; D013075:Sperm Capacitation / Q000502:physiology; D013076:Sperm Count / Q000662:veterinary; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology*
D002843:Chromatin