| Abstrakt: |
Les perturbations physiologiques potentiellement li?es ? la capture des poissons par filet maillant ou par ?puisette ont ?t? estim?es chez des brochets, sandres, perches, br?mes, chevesnes, carpes et tanches de la retenue hydro?lectrique de Pareloup (Aveyron). Toute capture provoque rapidement une hausse significative des taux de cat?cholamines (>10 ng.ml-1), Cortisol (> 100ng.ml-1) et glucose (> 1 g.l-1) et une baisse des taux d'hormones thyro?diennes (< 20 ng.ml-1) du plasma chez les sept esp?ces. Ces r?ponses physiologiques au stress de capture apparaissent significativement plus marqu?es suite ? la p?che par filet maillant et ce, notamment, chez les esp?ces carnassi?res. D'apr?s ces r?sultats, l'utilisation de filets maillants s'av?re inad?quate pour des recherches ? court terme sur la physiologie sanguine de populations naturelles de poissons, soulignant ainsi la n?cessit? apr?s ce type de p?che d'une mise en place d'infrastructures particuli?res (e.g., viviers, cages flottantes, etc.) pour la phase ult?rieure de r?cup?ration physiologique.The potential physiological disturbances experienced by fish as a result of capture with gill nets or landing nets were assessed in pike, pikeperch, perch, bream, chub, carp and tench from the hydroelectric reservoir of Pareloup (Aveyron). Capture of fish quickly resulted in both a significant elevation of plasma catecholamine (> 10 ng.ml-1) , cortisol (> 100 ng.ml-1) and glucose (> 1 g.l-1) levels and a drop in plasma thyroid hormone levels (< 20 ng.ml-1) in all species. These physiological stress responses were found to be highly increased following gill-netting, especially in carnivorous species. Hence, these data suggest that the use of gill nets is rather inadequate for short-term researches on blood physiology of ferai fish populations, then attesting to the necessity of settling up experimental facilities (e.g., fish-ponds, floating coops, etc.) following gill-netting to ensure a complete recovery of fish from capture stress. |
