Data/hora: 06/06/2024 06:19:25

Provedor de dados: 	5	
País: 	France	
Título: 	Reflex cardioventilatory responses to hypoxia in the flathead gray mullet (Mugil cephalus) and their behavioral modulation by perceived threat of predation and water turbidity	
Autores: 	Shingles, A; Mckenzie, David; Claireaux, Guy; Domenici, P.	
Data: 	2005-09	
Ano: 	2005	
Palavras-chave: 	Oxygen; Channel Catfish; Neotropical Fish; Cardiorespiratory Reflexes; Air Breathing Fish; Tambaqui Colossoma Macropomum; Salmon Oncorhynchus Tshawytscha; Aquatic Surface Respiration.	
Resumo: 	In hypoxia, gray mullet surface to ventilate well-oxygenated water in contact with air, an adaptive response known as aquatic surface respiration (ASR). Reflex control of ASR and its behavioral modulation by perceived threat of aerial predation and turbid water were studied on mullet in a partly sheltered aquarium with free surface access. Injections of sodium cyanide (NaCN) into either the bloodstream ( internal) or ventilatory water stream ( external) revealed that ASR, hypoxic bradycardia, and branchial hyperventilation were stimulated by chemoreceptors sensitive to both systemic and water O-2 levels. Sight of a model avian predator elicited bradycardia and hypoventilation, a fear response that inhibited reflex hyperventilation following external NaCN. The time lag to initiation of ASR following NaCN increased, but response intensity ( number of events, time at the surface) was unchanged. Mullet, however, modified their behavior to surface under shelter or near the aquarium edges. Turbid water abolished the fear response and effects of the predator on gill ventilation and timing of ASR following external NaCN, presumably because of reduced visibility. However, in turbidity, mullet consistently performed ASR under shelter or near the aquarium edges. These adaptive modulations of ASR behavior would allow mullet to retain advantages of the chemoreflex when threatened by avian predators or when unable to perceive potential threats in turbidity.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/2005/publication-637.pdf

DOI:10.1086/432143	
Editor: 	University of Chicago Press	
Relação: 	http://archimer.ifremer.fr/doc/00000/637/	
Formato: 	application/pdf	
Fonte: 	Physiological and Biochemical Zoology (1522-2152) (University of Chicago Press), 2005-09 , Vol. 78 , N. 5 , P. 744-755	
Fonte: 	2005, The University of Chicago