Biochemical and behavioral effects of diazinon exposure in hybrid striped bass

Abstract

The effects of environmental stimuli on biochemical processes may influence behavior. Environmental contaminants that alter behavior can have major impacts on populations as well as community structures by changing species' interactions. One important behavior is the ability to capture prey. We hypothesized that sublethal exposure to diazinon, an organophosphate pesticide, may lead to feeding behavior abnormalities in hybrid striped bass (Morone saxatilis x M. chrysops) through inhibition of brain acetylcholinesterase (AChE) activity. This can potentially reduce the organism's survival by affecting its ability to find and capture food. To test this hypothesis, bass were exposed to diazinon for 6 d, followed by a 6-d recovery period in clean water. Brain AChE activity and the ability of bass to capture prey fathead minnows (Pimephales promelas) were measured every third day. Exposed fish exhibited a concentration- and duration-dependent decrease in ability to capture prey. While bass in all diazinon treatment groups had significantly inhibited brain AChE activity, only the medium and high treatment groups showed a dose- and time-dependent increase in time to capture prey. Acetylcholinesterase activity also decreased in an exposure duration- and concentration-dependent manner. The AChE levels in exposed fish did not recover to control levels during the 6-d recovery period. These results suggest that sublethal exposure to AChE-inhibiting substances may decrease the ecological fitness of hybrid striped bass by reducing their ability to capture prey.

Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

“…For example, Beauvais et al (Beauvais et al, 2001) correlated decreased swimming speed of rainbow trout to increased AChE inhibition following 24 or 96 hour exposures, or 96 h exposure and a 48 h recovery period, to carbaryl or cadmium chloride. Other studies have also concluded that the severity of behavioral alterations by organophosphates stem from duration, compound and concentration specific AChE inhibition because decreases in fish locomotor activity levels were observed at higher treatment levels (Gaworecki et al, 2009). Because the type of behavioral responses may vary with timing and concentration, modulations in swimming speed were assessed (Ingebretson and Masino, 2013); we identified increased swimming bursts of larvae exposed to DZN at the highest doses but not at lower treatment levels.…”

Effects of an antidepressant mixture on the brain serotonin and predation behavior of hybrid striped bass

“…Behavioral assays followed procedures from previous studies in our laboratory [14,15,19]. Briefly, 3-d after the final individual training, the day 0 feeding event was quantified before the addition of antidepressant mixtures.…”

Evidence for behavioral preference toward environmental concentrations of urban‐use herbicides in a model adult fish

“…These effects may increase the probability of ecological death, or death by normal ecological processes such as predation, starvation, disease, or myriad other causes [7,8]. Several studies of fishes have determined that numerous pesticides may do just that, by altering locomotory activity [9,10] or by impairing the ability to detect predator scent [11][12][13][14].…”