Sperm handling in aquatic
animals for artificial reproduction
J. Beirao, M. Boulais, V. Gallego, J.K. O'Brien, S. Peixoto, T.R. Robeck, E. Cabrita
Theriogenology,
133: 161-178. 2019
doi: 10.1016/j.theriogenology.2019.05.004
Abstract
Artificial reproduction involves
collection and handling of gametes in a way that secures their quality and maximizes
the fertilization outcome. In addition to initial sperm quality, numerous steps
can affect the final result of fertilization, from the sperm collection process
until gamete mixing (or co-incubation) when the spermatozoon enters or fuses
with the oocyte. In this review, we summarize the whole process of sperm
handling, from collection until fertilization for fish, penaeid shrimp, bivalve
mollusks and marine mammals. To obtain sperm from captive animals, techniques
vary widely across taxa, and include stripping by abdominal massage or testis
surgical removal in fish, spermatophore collection in penaeid shrimps, gonadal
scarification or temperature shock in bivalve mollusks, and voluntary
collection via positive reinforcement in mammals. In most cases, special care
is needed to avoid contamination by mucus, seawater, urine, or feces that can
either activate sperm motility and/or decrease its quality. We also review
techniques and extender solutions used for refrigerated storage of sperm across
the aforementioned taxa. Finally, we give an overview of the different
protocols for in vivo and in vitro fertilization including activation of sperm
motility and methods for gamete co-incubation. The present study provides valuable
information regarding breeder management either for animal production or
species conservation.