Comparative Study of Semen Parameters and Hormone Profile in Small-Spotted Catshark (Scyliorhinus canicula): Aquarium-Housed vs. Wild-Captured

Abstract

Several chondrichthyan species are threatened, and we must increase our knowledge of their reproductive biology in order to establish assisted reproductive protocols for ex situ or in situ endangered species. The small-spotted catshark (Scyliorhinus canicula) is one of the most abundant shark species of the Mediterranean coast and is easy to maintain in aquaria; therefore, it is considered an ideal reproductive model. This study aimed to compare S. canicula male reproductive function in aquarium-housed (n = 7) and wild-captured animals, recently dead (n = 17). Aquarium-housed animals had lower semen volume (p = 0.005) and total sperm number (p = 0.006) than wild-captured animals, but similar sperm concentrations. In terms of sperm parameters, aquarium-housed sharks showed higher total sperm motility (p = 0.004), but no differences were observed regarding sperm viability, mitochondrial membrane potential, or membrane integrity. A morphometric study pointed to a significantly longer head (p = 0.005) and acrosome (p < 0.001) in wild-captured animals. The results of the spermatozoa morphological study of S. canicula were consistent with previous results obtained in other chondrichthyan species. With regard to sex hormones, testosterone levels were significantly lower in aquarium-housed animals (p = 0.001), while similar levels of 17β-estradiol and progesterone were found. In short, the present study provides evidence of good in vitro semen quality in S. canicula housed in an aquarium, underlining their excellent potential for application in reproductive technologies for this and other chondrichthyan species.

Exploring the Impact of Contaminants of Emerging Concern on Fish and Invertebrates Physiology in the Mediterranean Sea

“…One of the important parameters for choosing S. canicula as an indicator of pollutants [ 31 , 32 , 33 ] is that it is a hardy and resilient species that can tolerate a range of different environmental conditions. This means that it can be found in a range of different habitats and is less likely to be affected by natural fluctuations in the environment, making it easier to identify changes in pollutant levels [ 34 ].…”

Pharmacokinetic Studies in Elasmobranchs: Meloxicam Administered at 0.5 mg/kg Using Intravenous, Intramuscular, and Oral Routes to Nursehound Sharks (Scyliorhinus stellaris)

“…It consists of a reflex that causes a temporary state of inactivity and mild sedation while the animal is placed in dorsal recumbency, reducing the need for anesthetics or sedative agents that could otherwise influence the PK parameters of the drug under study ( 14 ). Scyliorhinid sharks are frequently maintained in aquariums worldwide and are also frequently used as model species for elasmobranch studies ( 15 , 16 ).…”

Andrology of shortnose guitarfish Zapteryx brevirostris (Müller & Henle, 1841) (Chondrichthyes, Trygonorrhinidae)

“…In contrast, all examined species of Holocephali have a long midpiece compared to the head (Jamieson, 2005). The midpiece may also be helically shaped, as in Squalus suckleyi (Linnaeus, 1758), or not, as in Z. brevirostris and Scyliorhinus canicula (Girard, 1855) (Muñoz‐Baquero et al ., 2021).…”