Page 4 - IJA-Vol.3-No.12

International Journal of Aquaculture, 2013, Vol.3, No.12, 55-62
http://ija.sophiapublisher.com
55
Research Report Open Access
Breeding and Larval Rearing of Bluefin Leatherjacket, Thamnaconus Modestus
(Günther, 1877) Under Commercial Scales
Jian Guan1, a , Zhenhua Ma2, a , Yongyun Zheng1 , Shuguang Guan1 , Chenglin Li1 , Hongjun Liu 1
1 Mari-culture Institute of Shandong Province, Qingdao 266002, P.R. China
2 South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, P.R. China
Corresponding author email:hongjunl@126.com; Authors
International Journal of Aquaculture, 2013, Vol.3, No.12 doi: 10.5376/ija.2013.03.0012
a: These authors contribute equally to this work
Received: 8 Apr., 2013
Accepted: 11 Apr., 2013
Published: 27 May, 2013
Copyright © 2013 Guan. This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article:
Guan, 2013, Breeding and Larval Rearing of Bluefin Leatherjacket, Thamnaconus Modestus (Günther, 1877) Under Commercial Scales, International Journal
of Aquaculture, Vol.3, No.12 55-62 (doi: 10.5376/ija.2013. 03.0012)
Abstract The spawning of wild caught broodstocks bluefin leatherjacket (Thamnaconus modestus) as well as egg and larval
development were studied under commercial scales. Spawning period was lasted 55 days from 15th June to 9th August, 2010. A total
of 4.3 million eggs were collected during the spawning period, and 65.5% of eggs were subjected to be properly developed. The
diameter of the eggs was 0.59 mm~0.63 mm. A total of 1.8 million newly hatched larvae were obtained in the present study with a
hatching rate of 41.7%. First feeding was observed on 3 day post hatching (dph), and the yolk sac was completely exhausted on 4 dph.
Metamorphosis occurred between 29 dph and 33 dph, at the total length (TL) of (11.93±2.18)mm. The growth in terms of TL can be
expressed as a polynomial equation TL=3.30394-0.31862(dph) + 0.02222(dph)2 ( r2=0.90362, n=427). After 70 days rearing, 0.3
million juveniles (TL>40mm) were obtained and the ratio of seedling/ newly hatched larvae was 5.62%. Our results demonstrated
that bluefin leatherjacket was feasible breeding under artificial environment, and our results will provided the technical guidance for
the further development of breeding on this species.
Keywords Thamnaconus modestus; breeding; larval rearing; growth; survival; ontogeny
Introduction
Monacanthid fishes are generally inhabiting both
temperate and tropical shallow waters, there are about 95
species are known worldwide (Nelson, 1984). The bluefin
leatherjacket Thamnaconus modestus (Günther, 1877)
belonging to the family of Monacanthidae, is an
important commercial bottom-dwelling marine filefish
which distributes in the northwestern Pacific Ocean
(Su and Li 2002). As a traditional commercial fishery
species, bluefin leatherjacket was widely fished in
China, Korea and Japan in the 1990s (Xu et al. 1992).
However, due to over fishing, bluefin leatherjacket
has become an endanger species in 1990s (Qian 1998;
Chen and Zhan 2000). In the past two decades, a
series of studies have been conducted, including
stocks and distributions identification (Xu et al. 1992;
Ding 1994; Chen and Zhan 2000), ecology factors
(Maekawa 1989), cryopreservation of sperm (Kang et
al. 2004), and genetics (Xu et al. 2010). Although
several studies have been done on the morphological
development and growth evaluation of bluefin leatherjacket
(Zhao and Chen 1980 ; Chen and Zheng 1984), most
of these studies were conducted under field survey.
Results from these studies are not consistent due to the
limitation of the sampling scales. Up to present, little
information is available on the developmental
characters of bluefin leatherjacket at early stage.
Furthermore, artificial breeding of this species is still
under trial scales.
The aim of this study was to explore the spawning in
captivity and larvi-culture of bluefin leatherjacket in
commercial scales. Our study will provide fundamental
information on the morphological and functional
development of bluefin leatherjacket larvae reared
under intensive conditions. Information such as the
age and size appearing transformation, culture
condition’s evaluation for mass production of high
quality seedling will benefit the further development
of the breeding protocol on this species.
1 Results and Discussion
1.1 Spawning and Egg Production
Spawning commenced on 15 th June, 2010 and
continued to 9th August, 2010. The peak of spawning