Freshwater Fish Release Urinary Pheromones in a Pulsatile Manner

FRESHWATER FISH RELEASE URINARY PHEROMONES IN A PULSATILE MANNER 

Department of Fisheries and Wildlife University of Minnesota St. Paul, Minnesota 55108 

All species of teleost fish examined to date have been found to use sex pheromones (Liley 1982 Liley Stacey 1983 Stacey, Kyle Liley 1986 Stacey, Cardwell, Liley, Scott Sorensen 1994). Further, where examined (about a dozen species Sorensen Stacey, this volume), these cues have been found to be derived from sex hormones. However, the temporal nature of pheromone release has yet to be characterized. Temporal characteristics of pheromone release (i.e. pulse frequency and duration and interpulse interval) might be important for two reasons (Dusenbery 1989). First, intermittent release of pheromone could produce temporal and spatial variations in pheromone concentration that might prevent or reduce sensory adaptation. Second, the temporal characteristics of pheromone release may provide information about the proximity and identity of the signal s sender. 

Advances in Chemical Signals in Vertebrates edited by Johnston et al. Kluwer Academic / Plenum Publishers, New York, 1999. 

Sources of sex pheromones have now been described in several species of fish, and whenever urine has been examined, it has been shown to have pheromonal activity (Liley 1982 Liley Stacey 1983 Stacey et al 1986 Stacey et al. 1994 Appelt, Sorensen Kellner 1995 Vermeirssen, Scott Liley 1997). This is notable because both studies which have described temporal characteristics of urinary release in fish have found urine to be released in a pulsatile manner (Fletcher 1990 Curtis Wood 1991). Unfortunately, neither study used fish known to be releasing pheromones. In a study of a freshwater fish, Curtis and Wood (1991) used external catheters and a radio-label to demonstrate that rainbow trout (Oncorhynchus my kiss) held individually in laboratory tanks urinated approximately every 30 min. In a study of a marine fish, the plaice (Pleuronectes platessa), Fletcher (1990) demonstrated that isolated plaice held in laboratory tanks urinate once every few days. The primary objective of this study was to determine whether a link between pheromones and pulsatile urinary release exists. 

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Appelt CW, Sorensen PW (1999) Freshwater fish release urinary pheromones in a pulsatile manner. In Johnston RE, Muller-Schwarze D, Sorensen PW (eds) Advances in chemical signals in vertebrates. Kluwer, New York, NY, p 247... 

Freshwater Fish Release Urinary Pheromones in a Pulsatile Manner... 

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