Journal of Environmental Biology
pISSN: 0254-8704 ; eISSN: 2394-0379 ; CODEN: JEBIDP
Google Search the Journal web-site:
Abstract - Issue Jan 2012, 33 (1) Back
|
Steroidal feedback on photoperiodic
induction of testicular growth and development in two bird
species Author Details |
|
|
|
Department
of Zoology, Ch. Charan Singh University, |
|
|
Department
of Zoology, Ch. Charan Singh University, |
|
I. Choudhary |
Department
of Zoology, Ch. Charan Singh University, |
|
(Corresponding author) |
Department
of Zoology, Ch. Charan Singh University, e-mail:
drskumar7@yahoo.com |
|
Publication Data Paper received: 25
October 2010 Revised
received: 25
February 2011 Accepted: 21 April 2011 |
Abstract Present study was performed
to demonstrate the effect of exogenous administration of testosterone
propionate on photoperiodic induction of testicular growth and development in
brahminy myna (Sturnus
pagodarum) and baya weaver (Ploceus philippinus). Two groups of brahminy
myna and baya weaver (n=5 each) were exposed
to15L:9D (group-I) and 9L:15D (group-II), and
received 30 ?g of TP bird-1 for 15 days. Then, the photoperiod was
reversed; the one receiving15L was exposed to 9L and vice versa. Observations
on body mass and testis volume were taken at the beginning and at 15 days
interval. In brahminy myna, a significant change in
body mass occurred under 9L:15D, transfer to 15L:9D,
but not under 15L:9D group, transfer to 9L:15D. Also, testes were stimulated
under 15L:9D transferred to 9L:15D, but not under
9L:15D transferred to 15L:9D. In baya weaver, body
mass increased under 15L:9D and 9L:15D for first 15
days and was maintained until the end of the experiment. Testes enlarged gradually
in both groups (15L:9D and 9L:15D transfer to vice
versa),? but it regressed in 15L:9D
group, transferred to 9L:15D after 45 days. Taken together it appears that
body mass response indicates the photoperiodic effect and gonadal
response indicates the hormonal effect. Finally results conclude that the
photoperiod and circulating testosterone levels feedback on to hypothalamus
regulates reproductive cycle in these birds. Key
words Brahminy myna, Baya weaver, Body mass,
Testosterone propionate, Steroidal feedback |
|
Copyright ? 2012 Triveni Enterprises. All rights reserved. No part
of the Journal can be reproduced in any form without prior
permission. Responsibility regarding the authenticity of the data, and
the acceptability of the conclusions enforced or derived, rest completely
with the author(s). |
|