Abstract
Simple SummaryMany species of rays and skates are endangered, and ex situ conservation programs developed by research centers and public aquaria could improve this situation. To reproduce these species in captivity, scientists need to know how to extract their sperm and how to conduct their artificial insemination; however, the anatomical diversity of the reproductive organs of this group of animals is a handicap. A comparison of the reproductive anatomies of 11 distinct species is presented here, emphasizing the important differences between the species when performing sperm extraction or artificial insemination. In addition, the process of obtaining sperm samples from both live and dead males is described in detail, using both cannulation and abdominal massage.The superorder Batoidea (rays, skates, and relatives), constitutes one of the most threatened group of vertebrates. Strengthening ex situ conservation programs developed in research centers and public aquaria could be a way of addressing this situation. However, captive breeding programs must be improved to prevent the capture of wild animals and to develop proper in situ reintroduction strategies. Sperm extraction and artificial insemination are two techniques commonly used in other threatened species, which could also be used in rays and the like. However, the different reproductive morphologies present within this group of animals may hamper both processes. Here, we present a comparison of the reproductive anatomies of 11 distinct batoid species, emphasizing the important differences between the species when performing sperm extraction or artificial insemination. Both male and female animals, belonging to the Rajidae, Dasyatidae, Torpedinidae and Myliobatidae families, from the Mediterranean Sea were studied. In addition, we describe the procedure to extract sperm using both cannulation and abdominal massage, either from live or dead batoids Finally, the obtention of motile sperm recovered from the oviducal gland of females is described. These techniques generate a new range of possibilities for the conservation of these threatened species.
Highlights
IntroductionAppearing almost 400 million years ago, Chondrichthyan fishes are an old and ecologically diverse group with a key role in the regulation of the ecosystems they inhabit [1,2]
The main objective of this study is to provide a useful guide of the anatomy of the reproductive system of batoids, with a particular focus on sperm procurement procedures, and to propose preliminary indications in the female anatomy to be considered during artificial insemination
Maturity of all the specimens was determined by gonad development, clasper calcification and their size according to bibliography [25]
Summary
Appearing almost 400 million years ago, Chondrichthyan fishes are an old and ecologically diverse group with a key role in the regulation of the ecosystems they inhabit [1,2]. The class is comprised of 1472 species [3], classically divided into the Holocephalans, commonly named chimaeras, and the Elasmobranchs, which include sharks and rays. This last group, rays and their relatives (skates, guitarfishes, sawfishes and the like), is the most diverse group among Chondrichthyan fishes, with 816 species accepted under the formal name of Batoidea [4,5,6]. Batoids possess life histories that make this group sensitive to elevated anthropic pressures [7,8], and overfishing and habitat destruction are the main drivers for the global decline of their populations [9,10]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
