Goldfish female pheromones

Female rainbow trout, Oncorhynchusmykiss, also release in their urine 17,20jSP. As in goldfish, this pheromone increases the plasma levels of gonadotropin II and testosterone in spermiating males Scott etal, 1994). Levels of 17,20jSP rises within 1 hour of exposure and peak at 3-4 hours. Milt production also increases (Vermeirssenetfl /., 1997). 

Sorensen P.W., Hara T.J., Stacey N.E. and Goetz F. (1988). F-prostaglandins function as potent olfactory stimulants that comprise the post-ovulatory female sex pheromone in goldfish. Biol Reprod 39, 1039-1050. 

Metabolites in urine or feces provide the energetically least expensive, and evolutionarily probably the original, chemical signals in vertebrates. Much of history of evolution has concerned the development by living things of responses to metabolites, sometimes their own and sometimes produced by others. Those organisms which developed satisfactory responses succeeded, and those which did not, failed. (Lucas, 1944). Interested parties, such as members of the opposite sex, can then spy and read pertinent information about sexual and dominance status, health and body condition, quality of diet, and more. For instance, female goldfish release sex pheromones in their urine that... 

All male fish pheromones are steroidal (Sorensen and Stacey, 1990). Many male fish release chemicals that attract females, stimulate them to spawn, and inhibit their aggression. As early as 1982, Liley compiled a long list of examples testes, as in goldfish (Stacey and Hourston, 1982), urogenital fluid, glands on the caudal peduncle (an anal fin appendage), mucus and urine, can be sources of male pheromones. 

FIGURE 7.1 Female goldfish pheromones, (a) The preovulatory pheromone 17a, 20/3-dihydroxypregn-4-en-3 one (b) the postovulatory pheromone 15-keto-prostaglandin 2 -... 

In fish reproduction, the best-investigated pheromone system is that of the goldfish [Carassius auratus). Here, sex steroids and prostaglandins play important roles. The female produces two pheromones sequentially a preovulatory primer pheromone and a postovulatory prostaglandin pheromone that act on the male. 

Dulka, J. G., Stacey, N. E., Sorensen, P. W. and van der Kraak, G. J. (1987). A steroid sex pheromone synchronizes male-female spawning readiness in goldfish. Nature 325, 251-253. 

Female Goldfish release a spawning pheromone in their urine. They release urine in pulses every 2-4 min. These pulses can be made visible by a blue dye in the urine (Appelt and Sorensen 1999). 

Obviously, these simple scenarios depict only a few of the most basic aspects of interspecific interference resulting from the use of nonspecific hormonal products and pheromones, and ignore others of potentially equal importance. Interference is unlikely to be either quantitatively or qualitatively symmetrical, even for closely related species using the same pheromone for the same function. In addition, pressures to reduce interference will vary enormously with life history characteristics e.g. the costs of interference for an iteroparous male (spawns many times in a season e.g. goldfish) may be negligible, whereas interference may eliminate reproductive success of a semelparous female (egg development is synchronous spawns but once a season or lifetime e.g. Pacific salmon) that responds to heterospecific odor. In any situation where selection leads to species-specific pheromonal function, we expect this will be achieved by evolution of an obligate, multiple-component pheromone system. As in insects, for which reproductive interference is important, these systems may contain novel components and/or use highly specific blends (Sorensen et al., 1998). 

Sorensen, P W., Stacey, N.E. Naidu, P. 1986. Release of spawning pheromone(s) by naturally ovulated and prostaglandin-injected, nonovulated female goldfish. In Chemical Signals in Vertebrates 4 (Ed. by D. Duvall, D. Muller-Schwarze R.M. Silverstein), pp 149-154. New York Plenum Press. 

Sorensen, P.W., Chamberlain, K.J. Stacey, N.E. 1989. Differing behavioral and endocrinological effects of two female sex pheromones on male goldfish. Horm. Behav. 23, 317—332. 

We found differences in the temporal nature of urinary release in two fish species. Ruffe release urine less often (different pulse frequency and inter-pulse interval) than goldfish, but the duration of each urination is the same as goldfish. As a result, ruffe spend considerably less total time urinating than goldfish (i.e. likely release less urine). This conclusion is supported by data from catheterized fish demonstrating that goldfish typically produce 0.75 ml of urine in 1.5 h while the same volume is produced in 6 h by ruffe. Future studies should closely examine urinary release in pheromone-releasing females of both species in association with female behavior and the effect of these patterns on male behavior. 

Appelt, C.W., Sorensen, P.W., Kellner, R.G. 1995. Female goldfish appear to release pheromonally-active F-prostaglandins in urinary pulses. In Proceedings of the 5th International Symposium on Reproductive Physiology of Fish (Ed. by F.W. Goetz P. Thomas, p. 270. Austin Fish Symposium 95. 

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