Behavior of Young Atlantic Salmon (Salmo salar) Exposed to or Force-Fed Fenitrothion, an Organophosphate Insecticide

Abstract

Exposure of young Atlantic salmon (Salmo salar) to 1.0 ppm fenitrothion for 15–16 hr caused a 50% decrease in the number holding territories 6 days following treatment. Some severely affected fish also swam stiffly and ceased feeding, but these effects disappeared within 48 hr following return to clean water. Territories were not reclaimed for approximately 2–3 weeks. Exposure to 0.1 ppm fenitrothion for 15–16 hr caused a lesser (20%) reduction in numbers of fish holding territories.When mealworms (Tenebrio sp.) injected with 2–5-μliters pure (100%) fenitrothion were force-fed to young salmon, 50% were regurgitated 8–12 hr afterwards. Almost all mealworms containing 10–20-μliter fenitrothion were regurgitated. The proportion of worms regurgitated remained constant during a week of daily force-feedings but, 24 hr after the third or fourth feeding, all fish except controls could be made to flex tetanically by rapping on the aquarium, and they made little attempt to escape a dipnet.

SENSITIVITY OF THE ANTARCTIC FISH Notothenia neglecta EXPERIMENTALY INTOXICATED WITH THE NON POLUTANT ANTICHOLINESTERASE AGENT MALATHION [O, O-Dimethyl S-(1,2-dicarbethoxyethyl) phosphorodithioate]

“…Blood serum cholinesterase (specific activity) in Notothenia neglecta, before (Control) and 12, 24 36 h and 10 days after Malathion (15 mg/kg) administration by intraabdominal injection. Cholinesterase specific activity was calculated as a ratio between units (UI) of the enzyme L -1 and the concentration of protein in g L The results obtained display the sensitivity of the Antarctic fish Notothenia neglecta to the toxic effects of Malathion, as compared to experiments carried out in fishes of temperate regions (PICKERING et al, 1962;PICKERING and HENDERSON, 1966;SYMONS, 1973;BENKE and MURPHY, 1974;POST and LEASURE, 1974;DUANGSAWASDI and KLAVENKAMP, 1979;LOPES et al, 1989;SILVA et al, 1993). The initial dose of 30 mg/kg used was based on those used by LOPES et al, (1989), who found that 40 mg/L of Malathion could induce severe intoxication in que freshwater fish Oreochromis niloticus.…”

“…The toxicity of organophosphate anti-ChE agents to freshwater fishes was described by PICKERING et al, (1962), PICKERING andHENDERSON (1966), COPPAGE (1972), SYMONS (1973), BENKE and MURPHY (1974), POST and LEASURE (1974), DUANGSAWASDI and KLAVERKAMP (1979), LOPES et al, (1989), SILVA et al, (1993). Assays with Malathion were carried out by POST and LEASURE (1974), who determined its sublethal effect to salmonid species.…”

Observations sur l'établissement du comportement de nage face au courant chez l'alevin de truite, Salmo trutta L., en ruisseau artificiel

“…Avec des eaux de qualités différentes, les résultats auraient pu être modifiés. Par exemple dans les cas de pollutions à partir d'insecticides organophosphorés, la locomotion de divers Salmonidés est altérée (Symons 1973 ;Bull et Me Inerney 1974) de même que leurs capacités d'apprentissage (Hatfield et Johanssen 1972). L'établissement de la nage statique chez l'alevin à l'émergence, pourrait être utilisé comme critère dans les recherches sur les effets de la pollution.…”

Sublethal effects of biologically treated petroleum refinery wastewaters on agonistic behavior of male orangespotted sunfish, Lepomis Humilis (girard)

“…Many of these studies involved changes in behavior as a result of pesticide exposure. These studies include investigations of the effects of fenitrothion on locomotion, feeding and social behavior of coho salmon (Bull and Mcinerney, 1975), fenitrothion on the ability of juvenile Atlantic salmon to hold territories (Symons, 1973), DDT on exploratory behavior on goldfish (Davy et al, 1973), DDT on light discrimination and learning by rainbow trout (McNichol! andMacKay, I 1975a and1975b), sevin on schooling behavior of Menidia (Weis and Weis, 1975), and parathion on susceptibility of shrimp to predation (Farr, 1977).…”