Behavioral responses of tilapia (Oreochromis niloticus) to acute fluctuations in dissolved oxygen levels as monitored by computer vision

Behavioral and ventilatory parameters have the possibility of predicting the stress state of fish in vivo and in situ. This paper presents a new image-processing algorithm for quantifying the average swimming speed of a fish school in an aquarium. This method is based on the alteration in projected area caused by the movement of individual fish during frame sequences captured at given time intervals. The image enhancement method increases the contrast between fish and background, and is thus suitable for use in turbid aquaculture water. Behavioral parameters (swimming activity and distribution parameters) and changes in ventilation frequency (VF) of tilapia (Oreochromis niloticus) responded to acute fluctuations in dissolved oxygen (DO) which were monitored continuously in the course of normoxia, falling DO level, maintenance of hypoxia (three levels of 1.5, 0.8 and 0.3 mg l(-1)) and subsequent recovery to normoxia. These parameters responded sensitively to acute variations in DO level; they displayed significant changes (P < 0.05) during severe hypoxia (0.8 and 0.3 mg l(-1) level) compared with normoxic condition, but there was no significant difference under conditions of mild hypoxia (1.5 mg l(-1) level). There was no significant difference in VF between two levels of severe hypoxia 0.8 and 0.3 mg l(-1) level during the low DO condition. The activity and distribution parameters displayed distinguishable differences between the 0.8 and 0.3 mg l(-1) levels. The behavioral parameters are thus capable of distinguishing between different degrees of severe hypoxia, though there were relatively large fluctuations. (c) 2006 Elsevier B.V. All rights reserved.

[1]  Lucas P. J. J. Noldus,et al.  Metabolic rate and level of activity determined in tilapia (Oreochromis mossambicus Peters) by direct and indirect calorimetry and videomonitoring , 1997 .

[2]  H. Hirata,et al.  Stress response and energy metabolism in various tissues of Nile tilapia Oreochromis niloticus exposed to hypoxic conditions. , 2002 .

[3]  A. Jahn,et al.  Impact of hypoxic conditions in the vicinity of Little Egg Inlet, New Jersey in summer 1976 , 1979 .

[4]  R. Wu,et al.  Hypoxia: from molecular responses to ecosystem responses. , 2002, Marine pollution bulletin.

[5]  A. Luchiari,et al.  Ventilatory frequency indicates visual recognition of an allopatric predator in naı̈ve Nile tilapia , 2003, Behavioural Processes.

[6]  N. Otsu.  A threshold selection method from gray level histograms , 1979 .

[7]  Cincinnati Oh Gamble Co.,et al.  Aquatic toxicology and environmental fate , 1988 .

[8]  R. E. Barreto,et al.  Caution for using ventilatory frequency as an indicator of stress in fish , 2004, Behavioural Processes.

[9]  J. C. Taylor,et al.  Physiological performance of juvenile southern flounder, Paralichthys lethostigma (Jordan and Gilbert, 1884), in chronic and episodic hypoxia. , 2001, Journal of experimental marine biology and ecology.

[10]  Christian E. W. Steinberg,et al.  Impact of the cyanobacteria toxin, microcystin-lr on behaviour of zebrafish, danio rerio , 1998 .

[11]  G. Iwama,et al.  Physiological changes in fish from stress in aquaculture with emphasis on the response and effects of corticosteroids , 1991 .

[12]  J. Diamond,et al.  Performance and Validation of an On-Line Fish Ventilatory Early Warning System , 1988 .

[13]  G. Iwama,et al.  Metabolic Responses Associated with Confinement Stress in Tilapia: The Role of Cortisol , 1997 .

[14]  Eitan Kimmel,et al.  Behavioral response of carp (Cyprinus carpio) to ammonia stress , 1998 .

[15]  G. Boeuf,et al.  Effects of hypoxia on respiratory physiology of turbot, Scophthalmus maximus , 2004, Fish Physiology and Biochemistry.

[16]  G. Thillart,et al.  Behavioral Strategy and the Physiological Stress Response in Rainbow Trout Exposed to Severe Hypoxia , 1996, Hormones and Behavior.

[17]  Eitan Kimmel,et al.  Monitoring the behavior of hypoxia-stressed Carassius auratus using computer vision , 1996 .

[18]  S. Kato,et al.  A quantification of goldfish behavior by an image processing system , 1996, Behavioural Brain Research.

[19]  T. Beitinger,et al.  Behavioral Reactions for the Assessment of Stress in Fishes , 1990 .

[20]  P. Williot,et al.  Respiratory responses to progressive ambient hypoxia in the sturgeon, Acipenser baeri. , 1993, Respiration physiology.

[21]  D. Burton,et al.  Cardiac and respiratory responses of rainbow trout, bluegills and brown bullhead catfish during rapid hypoxia and recovery under normoxic conditions. , 1973, Comparative biochemistry and physiology. A, Comparative physiology.

[22]  Shunji Mori,et al.  Acute toxicant warning system based on a fish movement analysis by use of AI concept , 1988, Proceedings of the International Workshop on Artificial Intelligence for Industrial Applications.

[23]  G. Dobson,et al.  Acute exposure to graded levels of hypoxia in rainbow trout (Salmo gairdneri): metabolic and respiratory adaptations. , 1988, Respiration physiology.

[24]  N. Smatresk,et al.  The influence of fish size on the avoidance of hypoxia and oxygen selection by largemouth bass , 2001 .

[25]  Colin Hunter,et al.  A video-based movement analysis system to quantify behavioral stress responses of fish. , 2004, Water research.

[26]  P. Williot,et al.  Circulatory and respiratory effects of an hypoxic stress in the Siberian sturgeon. , 1995, Respiration physiology.

[27]  E. Kimmel,et al.  The electrophysiological response of fish to hypoxia , 1997 .

[28]  Wannamaker,et al.  Effects of hypoxia on movements and behavior of selected estuarine organisms from the southeastern United States. , 2000, Journal of experimental marine biology and ecology.

[29]  Anders Fernö,et al.  Swimming behaviour as an indicator of low growth rate and impaired welfare in Atlantic halibut (Hippoglossus hippoglossus L.) reared at three stocking densities , 2004 .

[30]  T. Targett,et al.  Hypoxia tolerance of the mummichog: the role of access to the water surface , 2003 .

[31]  G. Mylonakis,et al.  Effects of background color on growth performances and physiological responses of scaled carp (Cyprinus carpio L.) reared in a closed circulated system , 2000 .

[32]  T. Arimoto,et al.  The background adaptation of the flatfish, Paralichthys olivaceus , 1991, Physiology & Behavior.

[33]  Nagaishi Hiroshi,et al.  Correlation between body color and behavior in the upside-down catfish, Synodontis nigriventris , 1989, Comparative Biochemistry and Physiology Part A: Physiology.

[34]  D. Sims,et al.  Metabolic trade-off between locomotion and detoxification for maintenance of blood chemistry and growth parameters by rainbow trout (Oncorhynchus mykiss) during chronic dietary exposure to copper , 1999 .

[35]  D. Kramer,et al.  Aquatic surface respiration, a widespread adaptation to hypoxia in tropical freshwater fishes , 2004, Environmental Biology of Fishes.

[36]  R. S. McKinley,et al.  Can feeding status and stress level be assessed by analyzing patterns of muscle activity in free swimming rainbow trout (Oncorhynchus mykiss Walbaum) , 2004 .

[37]  Tetsu Nemoto,et al.  A computer image processing system for quantification of zebrafish behavior , 2004, Journal of Neuroscience Methods.

[38]  J. Steffensen,et al.  SPONTANEOUS SWIMMING ACTIVITY OF ATLANTIC COD GADUS MORHUA EXPOSED TO GRADED HYPOXIA AT THREE TEMPERATURES , 1994, The Journal of experimental biology.