Efficacy of hormone stimulation on sperm production in an alpine amphibian (Anaxyrus boreas boreas) and the impact of short-term storage on sperm quality

Cecilia J Langhorne; Natalie E Calatayud; Carrie K Kouba; Scott T Willard; Theodore Smith; Peter L Ryan; Andrew J Kouba

doi:10.1016/j.zool.2021.125912

Efficacy of hormone stimulation on sperm production in an alpine amphibian (Anaxyrus boreas boreas) and the impact of short-term storage on sperm quality

Zoology (Jena). 2021 Jun:146:125912. doi: 10.1016/j.zool.2021.125912. Epub 2021 Mar 1.

Authors

Cecilia J Langhorne¹, Natalie E Calatayud¹, Carrie K Kouba², Scott T Willard³, Theodore Smith⁴, Peter L Ryan⁵, Andrew J Kouba⁶

Affiliations

¹ Mississippi State University, Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, College of Agriculture and Life Sciences, 32 Creelman Street, Mississippi State, MS 39762, USA.
² Mississippi State University, Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, College of Agriculture and Life Sciences, 32 Creelman Street, Mississippi State, MS 39762, USA. Electronic address: ckv7@msstate.edu.
³ Mississippi State University, Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, College of Agriculture and Life Sciences, 32 Creelman Street, Mississippi State, MS 39762, USA; Mississippi State University, Animal and Dairy Science, College of Agriculture and Life Sciences, 240 Wise Center Drive, Mississippi State, MS 39762, USA.
⁴ Colorado Parks and Wildlife, Native Aquatic Species Restoration Facility, 6655 County Road 106 South, Alamosa, CO, 81101, USA.
⁵ Colorado Parks and Wildlife, Native Aquatic Species Restoration Facility, 6655 County Road 106 South, Alamosa, CO, 81101, USA; Mississippi State University, Pathobiology and Population Medicine, College of Veterinary Medicine, 240 Wise Center Drive, Mississippi State, MS 39762, USA.
⁶ Mississippi State University, Wildlife, Fisheries and Aquaculture, College of Forestry, 775 Stone Boulevard, Mississippi State, MS 39762, USA.

PMID: 33743452
DOI: 10.1016/j.zool.2021.125912

Abstract

The Southern Rocky Mountain boreal toad (Anaxyrus boreas boreas) has disappeared from much of its range in the alpine regions of Central and Western North America, and restoration efforts are compromised by limited knowledge of this species' reproductive biology. This study aimed to establish whether assisted reproductive techniques could be used to improve breeding output in captive boreal toads by determining the most effective concentration of human chorionic gonadotropin (hCG) for induction of spermiation and viability of sperm during cold storage. Male toads (n = 21) were treated with a Low (3 IU g^-1), Medium (10 IU g^-1), or High (15 IU g^-1) concentration of hCG and spermic urine samples were collected over 24 hrs. Treatment effectiveness was evaluated by measuring the response rate, Total Motility (TM), Forward Progressive Motility (FPM), Quality of FPM (QFPM), and concentration. For short-term cold storage, spermic urine samples (n = 13) were stored at 4 °C for 14 days and sperm TM and FPM monitored daily. All treatments induced spermiation; however, a greater number of toads produced sperm in the Medium and High treatments compared to the Low. Overall, TM, FPM, QFPM and sperm concentration were similar across all three treatments, but variation existed in the timing and duration of peak sperm production. Sperm motility was maintained for up to 14 days in cold storage, although the quality slowly decreased over time. An effective reproduction strategy for the boreal toad will provide a means to improve captive breeding efforts and increase our understanding of the reproductive physiology of alpine Bufonids.

Keywords: conservation; ecological physiology; gamete; hormone; reproduction; sperm.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bufonidae / physiology*
Chorionic Gonadotropin / pharmacology*
Cryopreservation / veterinary
Male
Semen Analysis / veterinary*
Semen Preservation / veterinary*
Spermatogenesis / drug effects*

Substances

Chorionic Gonadotropin