Final Report - A.F.A. Sponsored Research Endocrine Fecology of Immature Birds

Abstract

EDITOR'S NOTE: The A.FA. has a research committee that has been quietly at work for several years now. At present Dr. Susan Clubb is chairing the committee and under her direction much progress is being made.

All money donated to the A.FA. for research is spent on research alone - none is diverted for any other purpose. The research committee evaluates various research projects and determines which are most appropriate for A.FA. funding. There are now five research projects that are sponsored by the A.FA. and that should ultimately provide data that will prove of great value to aviculture.

Jn 1982 Dr. Arden Berkowitz was awarded a grant to study the seasonal variation of sex steroids in young psittacines. The fallowing paper includes some of Dr. Berkowitz's results. This paper is the first in a series of papers representing the results of various A.FA. sponsored research.

by

Arden Bryan Bercovitz, Ph.D., Fred Frye, Jr. and Jim Bain Research Department Zoological Society of San Diego

Submitted for publication in Watchbird, 10114183

INTRODUCTION

My dictionary defines ology, informally: ' 'Any of various studies or concepts designed by terms ending in -logy and generically related.'' Examples are numerous: 1) physiology, study of functional living processes; 2) endocrinology, study of the physiology of endocrine glands; 3) fecalogy, study of the process of bowel and kidney wastes. Please, read that last example one more time. The term fecalogy™ [ 1] is a descriptive one and possibly unknown to you. I just invented it to describe my work and the study of birds through their droppings. The view from behind many rare, beautiful, imported birds has been amazing. The excrement that is useless to the bird may become more important than we ever knew it to be. Just think for a minute what can be learned about you by studying your garbage and waste materials. Modem archaeologists have found that Garbology is quite revealing of human behavior. The story behind the study of excretory hormones in captive birds is no less amazing.

Bird droppings convey several clues about many common questions asked by exotic bird breeders. Two questions frequently asked of me include: 1) what sex is it? 2) when will it successfully reproduce? Before giving you the latest details I want to acknowledge your partial financial support of this work. The AF A Special Research Committee deserves credit for recognizing and financing valuable research.

Experimental studies with two of the world's most endangered species has produced some exciting preliminary results: 1) indicating a better way to safely identify the sex in California condors (Gymnogyps californianus) soon after they hatch; 2) providing a nondisruptive method for evaluating the reproductive condition of Puerto Rican Amazon parrots (Amazona vittata) as they became sexually mature.

FECAL STEROID ANALYSIS

The analytic procedure for detecting changes in concentration of sex hormones in feces and urine of birds has been described for adult animals and successfully used to identify the sex in a wide variety of species (Czekala and Lasley, 1978; Bercovitz, et al., 1978; Stavy et al., 1979). The theory behind fecal steroid sexing is easily explained. The collected excrement is liquified, purified, hormone-analyzed and measured for total estrogens (E) and for testosterone (T), a major androgen. The final evaluation, as a ratio of E/T, can be used to identify adult males by their low E/T ratios, due to higher production and/ or excretion of T by active testicles. Females can be identified by high E/T ratios, due to higher production and/ or excretion of E by an active ovary.

In our last review, "Bird Sexing Methods - which should you choose?", (Bercovitz, 1981) I mentioned that the fecal steroid technique might not be capable of distinguishing either sex from birds that are immature, sexually inactive or birds with low total amounts of hormone due to age changes or for any reason. Age-related changes in steroid production from domesticated chickens provided evidence that active gonads were functionally distinct, male from female: 1) during the...