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International Journal of Marine Science 2014, Vol.4, No.45, 1-5
http://ijms.biopublisher.ca
1
A Letter Open Access
Incidence of Lordosis in the Cyprinid Fish,
Carasobarbus luteus
and the Shad,
Tenualosa ilisha
Collected from Barash Waters, Iraq
L. A. Jawad
1
, A. J. Al-Faisal
2
, F. M. Al-Mutlak
2
1. Manukau, Auckland, New Zealand
2. Marine Science Centre, University of Basra, Basra-Iraq
Corresponding author email
International Journal of Marine Science, 2014, Vol.4, No.45 doi: 10.5376/ijms.2014.04.0045
Received: 09 May, 2014
Accepted: 13 Jun., 2014
Published: 11 Aug., 2014
Copyright
©
2014 Jawad et al., 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:
Jawad et al., 2014, Incidence of Lordosis in the Cyprinid Fish,
Carasobarbus luteus
and the Shad,
Tenualosa ilisha
Collected from Barash Waters, Iraq,
International Journal of Marine Science, Vol.4, No.45 1
-
5 (doi: 10.5376/ijms.2014.04.0045)
Abstract
Incidences of severe lordosis involving two flexions are reported in a specimen of cyprinid fish
Carasobarbus luteus
and
Tenualosa ilisha
. For both species, the values for the angles lies between the lines passing through the sides of the vertebral column
and enclosing the curvature and the depth of the curvature of the angle were obtained. Also, the ratio of the vertebral column to the
fish total length of the deformed and the normal specimens of the two species were calculated. Possible causes for such anomalies
were discussed.
Keywords
Anomalies, Cyprinidae, Clupeidae, lordosis, vertebral column, Al-Hammar Marsh
Introduction
Skeletal deformities are relatively well described in
several species of fish (Antunes and Da Cunha, 2002;
Jawad and Al-Mamry, 2012; Jawad, 2013). They can
be a result of a metabolic alteration due to several
factors (physical, chemical and biological) inducing
deviations, irreversible, natural or induced, morphology
of fish (Divanach et al., 1996). These deformations are
generally rare in wild populations (Boglione et al.,
2001), and generally reflect an imbalance in the
environment that the organism living in. Factors
causing skeletal abnormalities in fish may also be
genetic (Afonso et al., 2000; Sadler et al., 2001) or
epigenetic.
Environmental conditions can contribute in causing
skeletal deformities especially during larval development
of fish. This may be due to the presence of pathogens
(Villeneuve et al., 2005; Yokoyama et al., 2004) or the
physico - chemical parameters in the environment,
such as brightness, dissolved oxygen, pH, temperature
and salinity (Ørnsrud et al., 2004; Sfakianakis et al.,
2004), exposure to certain toxic substances, potentially
teratogenic such as herbicides and organophosphorus
pesticides (Koyama, 1996), polyaromatic hydrocarbons
and heavy metals such as zinc, selenium, lead and
cadmium that can alter the process of bone development
and consequently lead to malformations (Louiz et al.,
2007). Therefore, skeletal deformities can be used as
an indicator of the presence of pollution in the
environment (Von Westernhagen and Dethlefsen, 1997).
Lordosis is one of the most severe deformities observed
in fishes; it develops either at the pre-hemal vertebrae
due to non-inflation of the swimbladder (Chatain and
Dewavrin, 1989) or at the hemal vertebrae as a result of
the intense water-current velocity facing larval stages
rearing (Kihara et al., 2002). The severity of the case of
lordosis ranges from slight axial modification to acute
lordosis angles (Divanach et al., 1996) and, therefore,
study of the effects of deformity on body shape is of
primary importance for fisheries and hatcheries
(Sfakianakis et al,. 2004).
Carasobarbus luteus
(Heckel, 1843) (Cyprinidae) is a
species that lives in freshwater in the Tigris-Euphrates
Rivers basin (Coad, 2010), while
Tenualosa ilisha
(Hamilton-Buchanon, 1822) (Clupeidae) is marine
anadromous species enter rivers and freshwater
marshes for laying eggs. Both species have high local
economic importance. They exposed to many physical
and chemical variations, from temperature to pollution,
in the most threatened ecosystems they are living in.