Abstract
The Zoological Society of San Diego has started a new service laboratory for sexing monomorphic birds by the novel technique of fecal steroid analysis, which measures sex hormones found in the bird's droppings. Participation will be open to aviculturists and institutions throughout the United States. A nominal fee of $15 .00 per bird will be charged and our first priority will be to assist those involved in breeding rare or endangered species. Address all inquiries to Arden Bryan Bercovitz, Ph.D., San Diego Zoo, San Diego, CA 92112. Please include a list of the species of birds you would like sexed.
GENERAL INFORMATION
Fecal steroid analysis was developed at the San Diego Zoo as a new method for sexing monomorphic birds. A very sensitive laboratory test is used to measure the amount of sex hormones, estrogen (E) and testosterone (T) which are present in the birds' droppings. These hormones are produced by both sexes, but in different proportions. The difference in excretory hormones between sexes is enhanced by reporting the test results as a ratio of estrogen/testosterone (E/T). Previous data from Psittacines (parrot species) have indicated that an E/T value less than 0 .5 represents a mature male and an E/T value greater than 2.0 represents a mature female.
Accurate sexing of your bird will depend on a comparison of its E/T values to previous results obtained from other birds of known sex from the same species. Hormone ratios from known males and females can differ greatly between species. Therefore, the appropriate reference data should be on file for your birds' species before doing the analysis. Please inquire about all species you want to be sexed, listing their full species name ( common and scientific).
The first priority of our sexing service laboratory will be to assist those aviculturists and institutions involved with breeding programs for rare or endangered species. An international award from Rolex, S.A., will provide the necessary subsidies for initially operating the laboratory. Therefore, during the first year only, a nominal fee of $15 .00 per bird will be charged for birds of unknown sex. Fecal samples will be solicited (free of charge, including postage) from birds of known sex in order to increase our file of reference data from a wider variety of species.
DO NOT send money or fecal samples unless you have made the necessary prearrangements. Address all inquiries to Arden Bryan Bercovitz, Ph.D., c/o Research Department, San Diego Zoo, San Diego, CA 92112. Please include the species name of all birds to be sexed. A fecal collection kit will be mailed to you with full instructions for fecal collection and handling; fees should accompany samples.