Relationships between in vivo and in vitro heterospermic ranking, embryo development, and sperm characteristics of Holstein and Jersey bulls

Heterospermic competition among bulls has been used in the past to establish relative fertility rankings in vivo and may be a more accurate fertility assessment and require fewer inseminations than binomial measures of fertility. The objectives of these experiments were to determine the relationships between heterospermic performance of bulls in vivo and in vitro, homospermic in vitro fertilization (IVF) and embryo development, and sperm characteristics. Extended semen from Holstein (n = 3; H2, H3, H4) and Jersey (n = 3; J1, J2, J3) bulls was either frozen homospermically or mixed in a 1:1, H:J ratio prior to freezing, resulting in 9 H/J heterospermic pairings that were later thawed for AI (H-VIVO; Kasimanickam et al., 2006) or IVF (H-VITRO-1). In 2 additional experiments, homospermic frozen/thawed semen from each bull was used for homospermic IVF, assessment of sperm motility (computer-assisted semen analysis, CASA) and viability (flow cytometric analysis of DNA fragmentation, acrosome integrity, plasma membrane integrity and disorder, and intracellular Ca2+), or standardized to equal numbers of motile sperm and recombined 1:1 resulting in the 9 H/J pairings for heterospermic IVF (H-VITRO-2). A competitive index (CI) was calculated for each bull based on the proportion of calves (H-VIVO) or cleaved embryos (H-VITRO-1 and H-VITRO-2) sired by each bull within pairing (n = 21 to 31 calves or embryos per pair per experiment). When CI = 0, 50% of calves or embryos were sired by a given bull on average across the 3 pairings; significant (P < 0.10) positive or negative deviations from 0 indicate a competitive advantage or disadvantage, respectively. The ranking of bulls was nearly identical for H-VITRO-1 and H-VITRO-2, indicating that standardization to equal numbers of motile sperm between bulls within pairings did not heavily influence heterospermic performance. Three bulls distinguished themselves across the various experiments. H4, the superior bull in vivo (CI = 0.671; P < 0.10), ranked among the least in H-VITRO-1 (CI = -0.532; P < 0.10) and H-VITRO-2 (CI = -0.266; P < 0.10). J2 ranked among the least in H-VIVO (CI = -0.308; P < 0.10) but was in both H-VITRO-1 (CI = 0.776; P < 0.10) and H-VITRO-2 (CI = 0.502; P < 0.10). J3 ranked among the least in all heterospermic scenarios (CI = -0.616, -0.444, and -0.428 for H-VIVO, H-VITRO-1, and H-VITRO-2, respectively; P < 0.10). Progressive motility was greater for bulls with a competitive advantage in vivo (P < 0.05). Homospermic IVF embryo cleavage rate was least for H4 compared to the remaining bulls (P < 0.05). Plasma membrane integrity was greatest (P < 0.05) for H3 (CI = -0.103, 0.364, and 0.489 for H-VIVO, H-VITRO-1, and H-VITRO-2, respectively; P < 0.10) compared to all other bulls. DNA fragmentation was greater (P < 0.05) for J2 than the remaining bulls. These data indicate that in vitro heterospermic performance was not an accurate indicator of in vivo heterospermic performance, and that deficiencies in sperm traits that affect in vivo heterospermic performance are not necessarily deficiencies in vitro and vice versa.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Animal Sciences

Grantor dc:publisher

The Ohio State University

Year dc:date

2013

Author dc:creator

• Utt, Matthew Douglas

Contributors dc:contributor

• Day, Dr. Michael L.

• Animal Sciences
• bull
• heterospermic
• in vitro
• in vivo
• fertility

Statement dc:rights

• unrestricted
• This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=osu1357274164

OAI identifier oai:identifier

oai:etd.ohiolink.edu:osu1357274164