Red wolf (Canis rufus) sperm quality and quantity is affected by semen collection method, extender components, and post-thaw holding temperature

• Published in: Theriogenology 2018-08, Vol.116, p.41-48
• Main Authors: Franklin, Ashley D., Waddell, William T., Goodrowe, Karen L.
• Format: Article
• Language: English
• Subjects: Cryoprotectant; Electroejaculation; Red wolf (Canis rufus); Semen extender; Sperm; Urethral catheterization
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/j.theriogenology.2018.05.007

Cryopreserving genetic resources is becoming increasingly important for species management. In the zoo-based red wolf (Canis rufus) population, inbreeding continues to increase in the absence of new founders. Through banking sperm, we preserve genetic diversity and create the ability to decrease inbreeding accumulation in the future. The quality and quantity of banked sperm can be affected by cryopreservation media and semen collection methods. This study's objectives were to further optimize semen extender used for red wolf sperm cryopreservation, investigate effects of post-thaw holding temperature, and to determine if urethral catheterization is an effective method for semen collection in this species. Semen collection via electroejaculation (EE) was performed on 39 adult red wolf males (ages 1 to 11) from 15 institutions. Urethral catheterization (UC) was attempted on a subset (n = 14) of those males, prior to EE. Thirteen different semen extenders were used for cryopreservation, which varied in osmolarity (HI or NORM), sugar source (glucose, fructose, or a combination), and cryoprotectant (glycerol or DMSO). Significant decreases in percent motility, forward progressive status (FPS), and acrosomal integrity were observed over time across all extenders (P