Sperm fatty acid composition as an indicator of quality and cryotolerance in blue catfish, Ictalurus furcatus

Authors: WOOD, KYLE - Auburn University; LITVAK, MATTHEW - Mount Allison University; LIYANAGE, SAMITHA - Auburn University; MARTIN, KAYLAN - Auburn University; TACKETT, V. - Auburn University; DUNHAM, REX - Auburn University; ROY, LUKE - Auburn University; WANG, XU - Auburn University; FAULK, CYNTHIA - Hudsonalpha Institute For Biotechnology; Beck, Benjamin; Abernathy, Jason; BUTTS, IAN - Auburn University

Submitted to: Theriogenology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/14/2025
Publication Date: 5/26/2025
Citation: Kyle R. Wood, Matthew K. Litvak, Samitha S.N. Liyanage, Kaylan A. Martin, V. MacKenzie Tackett, Rex A. Dunham, Luke A. Roy, Cynthia K. Faulk, Benjamin H. Beck, Jason W. Abernathy, Xu Wang, Ian A.E. Butts, 2025. Sperm fatty acid composition as an indicator of quality and cryotolerance in blue catfish, Ictalurus furcatus. Theriogenology. 245:117487. https://doi.org/10.1016/j.
DOI: https://doi.org/10.1016/j.theriogenology.2025.117487

Interpretive Summary: Hybrid catfish aquaculture, which constitutes over 50% of US catfish harvest, depends on the success of artificial fertilization between channel catfish, Ictalurus punctatus and blue catfish, I. furcatus. Unfortunately, this requires blue catfish males to be sacrificed to extract their valuable sperm and carry on their legacy to the next generation. Therefore, paternal resources must be used efficiently. This is particularly the case when using cryopreserved sperm, as each male’s cells are in limited supply. One way to assist in the selection of the highest performing blue catfish is through the use of biomarkers. However, there is a lack of biomarkers that can be used to predict fresh and frozen-thawed sperm quality for blue catfish. In this study, we compared sperm fatty acid percentages between fresh and cryopreserved male groups to determine potential biomarkers for sperm quality. Male groups were classified using sperm kinematics from both fresh and cryopreserved sperm and fatty acid percentages of fast swimming and slow swimming sperm were compared to pinpoint physiological differences between fresh and frozen-thawed sperm quality and cryotolerance. Significant differences were identified between fresh and cryopreserved sperm in Omega 3 and Omega 6 ratios as well as polyunsaturated fatty acid profiles. This knowledge can be used to create biomarkers of sperm quality and to formulate the fatty acid profile of catfish diets to improve sperm quality thereby improving their ability to handle cryopreservation.

Technical Abstract: Sperm membranes are composed of various fatty acids (FA) that have been linked to reproductive success across animal taxa, making it a potential biomarker. However, there is a lack of biomarkers that can be used to predict fresh and frozen-thawed sperm quality for the commercially important blue catfish, Ictalurus furcatus. In this study, we compared sperm FA percentages between fresh and cryopreserved male groups to determine potential biomarkers for sperm quality. Male groups were classified using sperm kinematics from both fresh and cryopreserved sperm. Fatty acid percentages of “good” (i.e. fast swimming sperm kinematics) and “bad” (i.e. slow swimming sperm kinematics) quality males were then compared to pinpoint physiological biomarkers of fresh and frozen-thawed sperm quality and cryotolerance. We found significant differences between fresh and cryopreserved sperm, where fresh sperm had significantly higher n-3:n-6 and EPA:ARA ratios as well as higher n-3 PUFAs and MUFAs, while cryopreserved sperm had higher concentrations of saturates. Cryopreserved sperm from good and bad males also had differences such as higher concentration of saturates (P < 0.001) in good males and significantly higher concentrations of MUFAs, n-6 PUFAs, n-3 PUFAs, and total PUFAs in bad males. Lastly, low levels of MUFAs and n-6 PUFAs in fresh sperm predicted high cryopreserved sperm kinematics. This knowledge can be used to create biomarkers of sperm quality and to formulate the FA profile of catfish diets to improve sperm quality thereby improving their ability to handle cryopreservation.