Dynamics of Condition Parameters and Organ Measurements in Pheasants

Authors

  • William L. Anderson Illinois Natural History Survey

DOI:

https://doi.org/10.21900/j.inhs.v30.162

Abstract

Environmental factors are recognized as the primary forces dictating the distribution, abundance, and physical condition of pheasants (Phasianus colchicus) and all other game species. These forces, whether beneficial or detrimental, manifest themselves within the physiological mechanisms carrying on the life processes of individuals constituting animal populations. Thus, it might be said that the physiological status of an animal is the expression of all of the environmental factors acting on the animal. This study elucidates changes in selected physiological parameters of wild pheasants in Illinois in relation to stresses that occur during the life cycle of this game bird.

Author Biography

  • William L. Anderson, Illinois Natural History Survey

    This study involved collecting 363 pheasants (274 hens and 89 cocks) from wild populations in east-central
    Illinois, weighing them, and dissecting them to obtain, in addition to body weight, weights or measurements of muscular tissues, fat deposits, and internal organs. The pheasants were collected during designated periods (growth, fall, winter, prebreeding. breeding, incubating, and molting) of the life cycle, 1966 through 1969. For the purposes of this study, all pheasants less than approximately 13 months of age—i.e., pheasants that had not entered into their first postnuptial molt—were considered juveniles, and all other birds were considered adults.  Multiple regressions indicated that (i) negative relationships existed between body weight, or sternal muscles, or legs, or fat deposits and the independent variables—eggs laid and collection date—for breeding hens; (ii) negative relationships existed between fat deposits and the independent variables—
    days of incubating and collection date—for incubating hens; and (iii) positive relationships existed between
    body weight, or sternal muscles, or legs, or fat deposits and the independent variables—primary feathers molted and collection date—for molting hens and molting cocks. Further testing indicated that the second independent variable—collection date—contributed more to the regressions for breeding hens and incubating hens than the first independent variable -- number of eggs laid and days of incubating, respectively.

Published

1972-07-31

Issue

Vol. 30 No. 1-8 (1972)

Section

Articles

License

Copyright (c) 1972 University of Illinois Board of Trustees

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

 

 

How to Cite

Dynamics of Condition Parameters and Organ Measurements in Pheasants. (1972). Illinois Natural History Survey Bulletin, 30(1-8), 455-498. https://doi.org/10.21900/j.inhs.v30.162