International Journal of Marine Science, 2017, Vol.7, No.20, 188-199
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For fishes, dorsal fin is important in locomotion and stability (Drucker and Lauder, 2005; Standen and Lauder,
2005); therefore it must be structured so as to face the hydrodynamic stresses with the least possible disbursement
of energy (Boglione et al., 1993). Any anomaly in the dorsal fin will weaken its flexibility, so obstructing the
swimming function of the fish. Combination of genome, environment and developmental noise can produce dorsal
fin deformities (Scheiner, 1993). In the present case of dorsal fin aberration in
Euryglossa orientalis
, it is
impossible to support the biotic and abiotic hypotheses in causing such anomalies without additional data.
Hyperostosis is present in several groups of vertebrates, including fishes (Capasso, 2005), where it has been used
by archeologists and fish systematists as a diagnostic criterion and as a taxonomical tool, respectively.
Several authors have considered hyperostosis as a non-pathological formation (Olsen, 1971; Desse et al., 1981;
Gauldie and Czochanska, 1990; Smith-Vaniz et al., 1995), but there is an acceptable reason to not consider
hyperostosis as a pathological condition is that it is a species-specific characteristic. Furthermore, the foreseeable
ontogenetic manifestation of these structures in fish species contradicts the hypothesis that it is a disease.
The size, shape, and position of the hyperostotic bones revealed in the two fish species reported on herein are
comparable with those given by Smith-Vaniz et al. (1995). The results of this study support this suggestion. The
shapes of the hyperostotic bones revealed in the present study are not distinctive from one another. Since only a
single specimen was obtained for each of the two Saudi species, it is not possible to test the hypothesis of Capasso
(2005) in correlating fish size (total length and weight) and number of hyperostotic bones found in each specimen
to increase body weight to facilitate bottom browsing.
When genetic disorder happened, albinism may generated in conjunction with environmental factors such as the
exposure to high concentrations of trace metals (Oliveira and Foresti, 1996) as these metals have the ability to
create a genetic random alteration (Wakida-Kusunoki and Amador-del-Ángel, 2013). The recessive autosomal
gene will find an opportunity to produce an albino individuals lacking of melanin pigmentations.
The possibility of the trace metals as the cause for albinism in our specimen looks possible as the Arabian Gulf
waters of Saudi Arabia has been shown to have high levels of trace metals due to the oil spillage from the large
number of the giant oil tankers that navigate this water way (Al-Saleh and Shinwari, 2002; Al-Homaidan, 2007).
Albinism may have less influence in feeding, growth and another aspects of life, such reproduction (Joseph, 1961).
Due to the considerable size of the albino specimen obtained in the present, our result agrees with Joseph (1961)
and Sandoval-Castillo (2006) permits us to postulate that, despite being an albino phenotype that makes an
individual more visible to predators, it can employ little impact on aspects of growth and performance of these
specimens.
This is the first report of albinism in the species
S. argus
from the Arabian Gulf area in general and the Saudi
Arabian waters in particular. This species of moderate commercial value and it is common in the fisheries catches,
with a high number of individuals being captured for decades from the Arabian Gulf area with no previous record
of albinism. This, then, is a rare event still unnoticed in most wild fish species, at least regarding adult individuals.
The partial amelanic patches were appeared on the body side a location where shown to be most affected by
several fish species. Such consistency in the location of the patches might be due to the manoeuvring of the genes
of the melanocortin system or of their products will have significant effects on a set of characters species.
Slominski et al. (2000) found that the level of activity of the different melanocortins is correlated across tissues.
Other studies indicated that with the aid of neuroendocrine communication, the activity of the melanocortin
system can be locally regulated and coordinated (Slominski and Wortsman, 2000; Slominski, 2005; Zbytek et al.,
2006) and such manipulation could vary between tissue of the fish body (Hoglund et al., 2000).
For Saudi Arabia as for other Arabian Gulf states, the fisheries industry is very important from both social and
economic perspectives. Management and monitoring of many commercial fish species are still in need by the
relevant fisheries agencies. In order to understand the exact cause and impacts of the fish aberration examined in
