Ontogenetic behavior of farm-bred Russian sturgeon (Acipenser gueldenstaedtii) prelarvae in a diel photoperiodic cycle: behavioral modifications in response to light intensity

Abstract

Russian sturgeon (Acipenser gueldenstaedtii) is commercially important in Korea because its caviar is highly prized. Although the early ontogeny of the species has been described, behavioral modifications in response to various light intensities or diel photoperiodicity patterns have not been studied extensively. The objective of the present study was to examine the behavioral characteristics of hatchery-produced A. gueldenstaedtii prelarvae over a diel photoperiodic cycle. During a diel light cycle comprising 16 h of daylight (450 lx), 4 h of dim light (10 lx), and 4 h of darkness (< 1 lx), newly hatched A. gueldenstaedtii prelarvae exhibited negative phototaxis in daylight (day 0-day 2), and this early behavior was not significantly affected by changes of light intensities. Rheotactic and non-rheotactic aggregation into schools was typical between days 3 and 6. Under the diel light cycle conditions described, rheotaxis was not influenced by environmental light intensity as much as non-rheotactic schooling behavior. Post-schooling behavior, which progressed from day 7 to day 8, did not change significantly during the diel light cycle. The data from the present study could be of practical value in developing a visual guide for assessing the fitness and quality of Russian sturgeon prelarvae under diel light cycle conditions in hatcheries.

Superoxide Dismutase Multigene Family from a Primitive Chondrostean Sturgeon, Acipenser baerii: Molecular Characterization, Evolution, and Antioxidant Defense during Development and Pathogen Infection

“…In accordance with behavioral modifications, the gradual decreases in expression from either 5 (for AbSOD1) or 7 dph (for AbSOD2) could reflect the decreased demand for antioxidant responses owing to the reduced activity and energy-saving behavior. After the evacuation of the pigment plug at 9–10 dph [ 39 , 97 ], prelarvae enter the larval stage, with a transition from endogenous nutrition to exogenous feeding (11 dph), and their locomotor activity begins to recover, which is in agreement with the rebound in SOD expression (for both AbSOD1 and AbSOD2 at 11 dph) to prepare the antioxidant defenses for increased metabolic rates.…”

Evaluation of Russian sturgeon (Acipenser gueldenstaedtii) Semen Quality and Semen Cryopreservation

“…Semen was collected during the breeding season from five different males, all 12 years old. Spermiation was induced using Luteinizing hormone-releasing hormone agonists (LH-RH, SIGMA-ALDRICH L4513), administered intramuscularly in a 20 μg kg −1 body weight dose, 24–30 h before the estimated time for semen collection [ 37 ]. All animal manipulation procedures were performed under clove oil anesthesia (0.5 mL L −1 for 5 min), and no animals were harmed or killed during these experiments.…”

Behavioral characteristics of a chondrostean sturgeon species Acipenser baerii prelarvae in response to different environmental light intensities in a diel photoperiodic cycle

“…Light is one of the most critical factors to influence behavioral and physiological characteristics of sturgeons particularly during their early life stages (Rodriguez and Mueller and Neuhauss, 2010). Phototactic properties of sturgeon species have been known to be innately acquired at the stage of hatching, and newly hatched prelarvae (i.e., yolk sac-bearing larvae) represent a wide spectrum of behavioral interactions with environmental lights (Dettlaff et al, 1993;Kim et al, 2019b).…”