The effect of salinity on osmoregulation and development of the juvenile fat snook, Centropomus parallelus (POEY)

Abstract

Eurihaline fish support waters with different salt concentration. However, numerous studies have shown that salinity can affect fish development. Thus, the effect of salinity change from 20 to 5 and 35 on survival, weight, length, gill chloride cell ultrastructure and gill Na + , K + ATPase activity was evaluated in Centropomus parallelus following short-term (6, 24 and 96 hours) and long-term exposure (30 and 60 days). Salinity did not affect C. parallelus survival, final weight and length. The quantity of chloride cells increased visibly at salinities of 5 and 35, with the cells exhibiting the typical features of uptake and secretory cells, respectively. Na + , K + ATPase activity in the gill of the C. parallelus was significantly greater at a salinity of 5 than at a salinity of 20 or 35 after 96 hours, but not after 30 or 60 days. These results indicate that salinity change from high to low salt water induces gill chloride cell and Na + , K + ATPase activity adaptations after short-term exposure. However, after long-term exposure at salinity 5, gill Na + , K + ATPase activity is no more necessary at high levels. The increase in salinity to 35 does not induce significant change in gills. Juveniles of C. parallelus may thus be capable of acclimating to salinities of 5 to 35 for 60 days without significant effects on development.Keywords: Centropomus parallelus, chloride cell, osmoregulation, Na + , K + ATPase. O efeito da salinidade sobre a osmoregulação e o desenvolvimento do juvenil de robalo-peva, Centropomus parallelus (POEY) ResumoPeixes eurihalinos suportam águas com diferentes concentrações de sal. Contudo, muitos estudos têm mostrado que a salinidade pode afetar o desenvolvimento do peixe. Portanto, o efeito da mudança de salinidade de 20 para 5 e 35 na taxa de sobrevivência, peso, comprimento, morfologia das células de cloreto branquiais e atividade da Na + , K + ATPase foram avaliadas no Centropomus parallelus após curto (6, 24 e 96 horas) e longo tempo de exposição (30 e 60 dias). A salinidade não afetou a sobrevivência, o peso e comprimento final do robalo-peva. A quantidade de células de cloreto aumentou visivelmente nas salinidades 5 e 35, exibindo morfologias típicas de células que absorvem e secretam sal, respectivamente. A atividade da Na + , K + ATPase nas brânquias do C. parallelus foi significativamente maior na salinidade 5 do que nas salinidades 20 ou 35 após 96 horas, mas não após 30 e 60 dias. Esses resultados indicam que a mudança de alta para baixa salinidade provoca adaptações nas células de cloreto e na atividade da Na + , K + ATPase branquial em curto prazo. Contudo, após longa exposição na salinidade 5, a alta atividade da Na + , K + ATPase branquial não é mais necessária. O aumento de salinidade para 35 não induz mudanças significativas nas brânquias. Portanto, juvenis de C. parallelus possuem a capacidade de aclimatação nas salinidades de 5 a 35 sem efeitos significativos no desenvolvimento após 60 dias.Palavras-chave: Centropomus parallelus, célula de cloreto, osmoregula...

Habitat residency and movement patterns of Centropomus parallelus juveniles in a subtropical estuarine complex

“…This behaviour was expected, based on the frequent records of C. parallelus individuals in areas of different salinities within the PEC (Felix et al, 2007;Contente et al, 2011;Vitule et al, 2013). Furthermore, laboratory experiments showed that growth and survival of individuals were not significantly affected by salinity shifts (Tsuzuki et al, 2007;Sterzelecki et al, 2013). Similar conclusions were reached for Centropomus nigrescens Günther 1864 (Nonell, 1995) Backcalculation estimates from daily increments recorded in the otoliths indicate that C. parallelus has a protracted spawning season from May to January, with a peak between October and January (spring and summer).…”

“…This behaviour was expected, based on the frequent records of C. parallelus individuals in areas of different salinities within the PEC (Felix et al ., ; Contente et al ., ; Vitule et al ., ). Furthermore, laboratory experiments showed that growth and survival of individuals were not significantly affected by salinity shifts (Tsuzuki et al ., ; Sterzelecki et al ., ). Similar conclusions were reached for Centropomus nigrescens Günther 1864 (Nonell, )…”

“…Several experiments for aquaculture purposes showed that C. parallelus juveniles can grow and survive in salinities from 0 to 35 (Tsuzuki et al, ; Sterzelecki et al, ). Although a higher food uptake efficiency was observed at low salinities (5) (Rocha et al, ), a more successful larval hatching rate and fish development was recorded at higher salinities (30–35) (Araujo & Cerqueira, ).…”

Dietary protein requirement in common snook (Centropomus undecimalis ) juveniles reared in marine and brackish water

“…An insu cient protein level produces low growth, while an excess results in a surplus of amino acids that are used to produce energy, which increases the level of ammonium excretion to the system and causes a poor immune response in sh (Xia et al 2015). Fish of the genus Centropomus are marine species with the vast majority of them having euryhaline characteristics, along with the ability to inhabit waters in the range of 5 to 35 UPS, and to adapt physiologically to osmoregulation in the short and long term, with a variable energy cost (Sterzelecki et al 2013). Therefore, the objective of the present study was to determine the optimal dietary protein requirements for Centropomus undecimalis juveniles at two di erent salinities (5 and 36 UPS) and their e ect on growth and survival.…”

Effects of Salinity on Gills’ Chloride Cells, Stress Indices and Gene Expression of Asian Seabass (Lates Calcarifer, Bloch, 1790)

“…Similarly, remarkable increment of CC counts in the gill laments was reported in different hyperosmotic-acclimated sh such as European sea bass (Dicentrarchus labrax,Varsamos et al, 2002), killi sh(Lima & Kültz, 2004), Adriatic sturgeon (Acipenser naccarii, Martínez-Álvares et al, 2005), Mozambique tilapia(Hiroi et al, 2005), fat snook (Centropomus parallelus,Sterzelecki et al, 2013). It should be mentioned that sh reared at 15‰ had the smallest nucleus diameter in CC suggesting these sh were at isosmotic condition and less osmotic stress pressure was on them; however, sh reared at other WS showed nucleus hypertrophy mas a result of hypo and/or hyperosmotic stress condition.…”