Search the Journal web-site through Google:
Abstract - Issue Sep 2018, 39 (5) Back
nstantaneous and historical temperature effects on a-pinene
of 17a-ethinylestradiol on embryo survival, hatchability and larval
deformities in African catfish, Clarias gariepinus
Nadirah1,2*, M. A. B. Tajuddin1, M. Najiah1,2,
M. Abd Ghaffar1,2,3 and K.L. Lee1
Fisheries and Aquaculture Sciences, Universiti Malaysia Terengganu, 21030,
Tropical Aquaculture, Universiti Malaysia Terengganu, 21030, Terengganu,
Research Center, Faculty of Science and Technology, Universiti Kebangsaan
Malaysia, 43600 Bangi, Selangor, Malaysia
Author E-mail: firstname.lastname@example.org
Paper received : 16.05.2016
Revised received : 20.06.2016
Re-revised received :
Accepted : 28.12.2017
estrogens, such as 17a-ethinylestradiol
(EE2), are common in contraceptive pills, and EE2 levels may be
present in various waterways. As such qualitative and quantitative
assessment on the impact of EE2 on aquatic organisms are needed.
The main objective of the study was to determine the effect of EE2
at the environmentally relevant concentrations on embryonic survival,
hatchability and larval deformities in African catfish (Clarias gariepinus)
cultured under laboratory conditions.
Methodology: Two healthy
sexually mature males and two gravid female fish weighing 0.8 to 1.0 kg were
selected based on the external morphological features. They were then
subjected to induced breeding with ovaprim, given at 0.25 b.wt. and 0.5 ml kg-1
b.wt. for males and females, respectively. Eight hundred fertilized eggs
(embryos) were randomly distributed into four groups with 100 eggs per group
in duplicate in respective concentrations of EE2: control (0 ng l-1),
25 ng l-1, 50 ng l-1 and 100 ng l-1, each in
1000 ml glass beakers. Percentage of normal embryonic survival and
abnormalities were recorded prior to hatching at 30th hour post fertilization
(hpf), while 20 post-hatch larvae were sampled randomly from each group to
determine the number of larvae displaying morphological deformities.
Results: At 30th
hpf, only 62% of the eggs survived when incubated with 100 ng l-1
of EE2, while the highest survival was observed in the control
group (92%). The lowest hatching success rate of 55% was seen in the 100 ng l-1
group, which was significantly lower from the embryos exposed to 0 or 25 ng l-1.
Interpretation: The results
suggest that EE2 at 100 ng l-1 affected the early life stages of C.
gariepinus, thus, a closer monitoring on EE2 discharge into
the aquatic environments is essential.
© 2018 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).