Skip to main content
ARS Home » Southeast Area » Stoneville, Mississippi » Warmwater Aquaculture Research Unit » Research » Publications at this Location » Publication #395841
Research Project: Biophotonics - The Application of Novel Imaging Methodologies to Livestock Production Research

Location: Warmwater Aquaculture Research Unit

Title: Fertilization potential of cold-stored Fowler’s toad (Anaxyrus fowleri) spermatozoa: temporal changes in sperm motility based on temperature and osmolality

Author
item ARREGUI, LUCIA - Collaborator
item KOUBA, ANDREW - Mississippi State University
item GERMANO, JENNIFER - Collaborator
item BARRIOS, LAURA - Collaborator
item MOORE, MARIAN - Collaborator
item VANCE, CARRIE - Mississippi State University

Submitted to: Reproduction, Fertility and Development
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/21/2021
Publication Date: 11/1/2021
Citation: Arregui, L., Kouba, A.J., Germano, J., Barrios, L., Moore, M., Vance, C.K. 2021. Fertilization potential of cold-stored Fowler’s toad (Anaxyrus fowleri) spermatozoa: temporal changes in sperm motility based on temperature and osmolality. Reproduction, Fertility and Development. 34(5):461-469. https://doi.org/10.1071/RD21037.
DOI: https://doi.org/10.1071/RD21037

Interpretive Summary: Ectotherm sperm quickly lose motility when kept at room temperature and that loss of motility is exacerbated when the osmolality is dropped by diluting the sperm in water. Thus, keeping the sample in spermic urine without further dilution, and immediately storing the sample at 4°C until evaluation, IVF or long-term biobanking procedures can be implemented. In this cold storage environment, sperm remained motile for up to 14 days and showed a relatively high rate of fertilization for up to 8 days. These results provide additional knowledge of non-mammal sperm physiology relative to environmental triggers and fertilization, yet also provide a pathway for exploitation by biologists for assisted breeding, genetic management of non-mammalian species, with particular extension to fishes in aquaculture stock lines.

Technical Abstract: Asynchrony of gamete release is problematic in captive breeding programs but can be overcome by short-term storage of spermatozoa. Hormonally induced sperm from the model species Anaxyrus fowleri were used to determine storage conditions for optimal fertilization capacity. Sperm motility was measured over time, as a function of storage temperature (4°C or 22°C) and solution osmolality (7–40 mOsm/kg). Sperm at 40 mOsm/kg (spermic urine) stored at 4°C exhibited higher motility compared to 22°C. Also, sperm stored at 40 mOsm/kg retained higher motility compared to sperm stored below 15 mOsm/kg at both temperatures. Under optimal storage conditions (40 mOsm and 4°C) a 30% decrease in sperm motility occurred within 24 h, however, subsequent loss of sperm motility was lower (<10%/day) for days 2–8 thereafter. Sperm samples stored for 1–8 days under optimal conditions were tested for fertilizing capacity by conducting in vitro fertilization trials. Sperm stored for 8 days yielded 48% neurula development, similar to sperm stored for 1 day, which produced 60% neurula development. Overall, sperm stored for up to 8 days at 4°C as spermic urine retained fertilizing capacity and thus can be used to circumvent asynchronous gamete release in assisted breeding efforts for non-mammal species.