Ventilatory responses to skin extract in catfish

Autor(es)

Barreto, Rodrigo Egydio ^[1] ; Barbosa Junior, Augusto ^[2] ; Hoffmann, Anette ^[2]

Afiliação do(s) autor(es)

^[1] UNESP, Inst Biociencias, Dept Fisiol, BR-18618970 Botucatu, SP - Brazil

^[2] Univ Sao Paulo, Lab Neurofisiol Comparada, Dept Fisiol, Fac Med Ribeirao Preto, BR-14049900 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AQUATIC BIOLOGY; v. 15, n. 3, p. 205-214, 2012.
• Citações Web of Science: 9

Resumo

The ventilation rate (VR) of an ostariophysan fish, the speckled catfish Pseudoplaty stoma coruscans, exposed to a chemical alarm cue was measured in the present study in multiple contexts. The influence of the extraction techniques, skin donor food intake and quantity of the alarm cue (skin extract) on this autonomic response was considered. Overall, the catfish VR decreased significantly when exposed to the skin extract (chemical alarm cue) compared with exposure to distilled water (control). No effect of the extraction technique was found. Increasing doses of the skin extract induced a VR reduction of similar magnitude. However, extract obtained from daily-fed fish induced a significant decrease in the VR, whereas extract obtained from food-restricted fish did not induce any change in the VR. Thus, food intake was associated with the production of a more easily recognizable alarm cue in the speckled catfish. Interestingly, this effect was not related to differences in the number of club cells in the donor catfish epidermis. Dashing, or rapid swimming, a normal component of the alarm response in fish, including this catfish species, was not observed here, and hypoventilation was always associated with no swimming reaction. Together, these results suggest that hypoventilation is a reaction to a chemical alarm cue, likely resulting in improved crypsis, causing the fish to become less easily perceived by a potential predator that usually strikes prey in response to movement. (AU)

• Processo FAPESP: 05/04771-5 - Resposta de alarme no peixe pintado Pseudoplatystoma corruscans: uma abordagem fisiológica comportamental
• Beneficiário: Rodrigo Egydio Barreto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado