Fluctuating salinity effect onSphoeroides annulatus(Jenyns 1842) physiological responses

Abstract

Euryhaline fish, such as the Bullseye puffer Sphoeroides annulatus (Jenyns 1842), experience sudden salinity changes in their natural environment, which is more common than the exception, so they must adapt to survive and cope with extreme salt conditions. Therefore, Bullseye puffer juveniles were exposed to short-term stress (39 hr) by fluctuating salinity conditions (41, 35, 29, 23, 17, 11, 5, 11, 17, 23, 29, 35, 41 psu) with a 3-hr interval between each point at 26 ± 1°C in a respirometer chamber and acclimation reservoirs. Responses to oxygen consumption rate (OCR:oxygen-nitrogen atomic ratio (O:N 17-30), osmoregulatory pattern (blood osmotic pressure from 342.4 to 332.8 mmol/kg) and changes in expression levels of Na + /K + -ATPase in the gills (higher values at higher salinities) were measured. Although some signs of stress were detected below the iso-osmotic point (11.4 psu), the puffer fish is a strong euryhaline fish that survives under these conditions. Nonetheless, it could recover when salinity returned to the initial acclimation point because Sphoeroides annulatus is able to live in a wide range of environments with wide natural salinity fluctuations; thus, a common practice in aquaculture has been to expose fish to low salinity for several reasons discussed in this study. This capacity reveals its high plasticity to saline adaptation from 41 to 5 psu an up from 5 to 41 psu, all in less than 2 days. K E Y W O R D S

Health risk of consuming Sphoeroides spp. from the Navachiste Lagoon Complex due to its trace metals and organochlorine pesticides content

“…The puffer sh Sphoeroides spp. is a euryhaline sh that inhabits coastal lagoons and estuaries [77], and NAV is a coastal lagoon neighbored by intensive agriculture and aquaculture that extend for more than 100,000 ha of territory. These intensive activities constantly dispose of their residues, after irrigation or water exchange, directly to the lagoon through discharge channels.…”

Physiological responses to salinity stress in the Managua Cichlid,Cichlasoma managuense

“…This is expected because black porgy is a marine species which should have a higher plasma osmolality and isosmotic point than that of freshwater C. managuense in this study. In addition, teleost could save energy on osmoregulation and convert it to other pathways such as growth (Gaumet, Boeuf, Severe, Le Roux, & Mayer‐Gostan, 1995; Ma, Zheng, et al, 2016; Pérez‐Robles et al., 2019).…”

“…Salinity is one of the most important ecological factors affecting the growth and metabolism of aquatic organisms, and salinity changes may seriously affect osmoregulation and physical state of teleosts (Abdel‐Rahim et al., 2020; Dong, Dong, & Meng, 2008; Duarte et al., 2018; Huang et al., 2020; Pérez‐Robles et al., 2019; Rahmah, Liew, Napi, & Rahmat, 2020; Ruiz‐Jarabo et al., 2019; Vargas‐Chacoff, Muñoz, Ocampo, Paschke, & Navarro, 2019; Wang et al., 2019; Yang & Min, 2019; Zhang et al., 2017; Zhu et al., 2018). However, beneficial effects of appropriate salinity have been reported in high growth rate, reproductive activity and disease resistance activity (Sui, Huang, Kong, Lu, & Wang, 2016; Urbina & Glover, 2015; Wang, Li, Li, Zhang, & Lu, 2016).…”

Health risk of consuming Sphoeroides spp. from the Navachiste Lagoon complex due to its trace metals and organochlorine pesticides content

“…Among the polluted seafood species reported in the NAV are those of the Tetraodontidae family, like the pufferfish Sphoeroides spp. 21 , a euryhaline fish that inhabits coastal lagoons and estuaries 22 , and its feeding habits include zoo benthivores and omnivores, including bivalves, gastropods, and macrophytes 23 – 25 . The commercial value of the pufferfish Sphoeroides spp.…”