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Genetic analysis of the complete G gene of viral hemorrhagic septicemia virus (VHSV) genotype Ie isolates from Turkey
Get PDFViral hemorrhagic septicemia virus (VHSV) is an enveloped non-segmented, single-stranded, negative-sense RNA virus that belongs to the Novirhabdovirus genus of the family Rhabdoviridae. This virus causes economically significant diseases in farmed rainbow trout, in Turkey, which is often associated with the transmission of pathogens from European resources. In this study, moribund rainbow trout (Oncorhynchus mykiss) samples were collected during an outbreak of VHSV in a rainbow trout fish farm in Bolu Province of Turkey in 2006. In addition, two VHSV strains were isolated from wild turbot (Scophthalmus maximus) in Trabzon Province of the Black Sea region of Turkey during a field survey. We have sequenced the full-length glycoprotein (G) gene of three VHSV isolates and compared them with 25 previously published gene sequences. Based on a complete gene nucleotide sequence, Turkish VHSV isolates were classified into class Ie of genotype I, which is closely related to GE-1.2 isolate (97.1-97.5% nucleotide identity and 98.2-98.4% amino acid identity) found in Georgia more than 30 years ago. These isolates could be an indigenous type of VHSV distributed in the Black Sea. On the other hand, Turkish isolates have 97.5-97.6% nucleotide identity and 98.8-99% amino acid identity with Finnish, Danish, and Norwegian isolates which are classified under Ib and Id. These results suggest that Turkish VHSV isolates may have orginated from Europe and co-circulated with indigenous strains which can threaten the aquaculture industry in Turkey
Molecular diversity of Symbiodinium spp. within six coral species in Larak Island, the Persian Gulf
Get PDFReef-building coral harbor communities of photosynthetic taxa of the genus Symbiodinium (zooxanthellae). The genus Symbiodinium is currently classified into nine genetic clades (A–I). Various corals harbor different Symbiodinium clades; some show specificity to a single strain. Coral and their zooxanthellae are sensitive to environmental stresses. In the Persian Gulf, coral reefs are subject to harsh environmental conditions including extreme temperatures and high salinity. This is the first study to use clade specific primers to clarify the diversity of Symbiodinium in each coral species of Larak Island. For this purpose six coral species were collected at two different locations in Larak Island. After DNA extraction, PCR amplification was performed using clade specific primers. The results showed that multiple Symbiodinium clades are hosted by most coral species. In addition, among thirteen obtained Symbiodinium sequences, the frequency of either tree [sic] clades, A, C and D was almost the same. Corals species may contain different clades of Symbiodinium depending on the region and on the tolerance characteristics of each clade. Thus, knowledge of zooxanthellae diversity associated with scleractinian can contribute to a better understanding of the sensitivity of corals to environmental conditions
Meristic variations and skeletal deformities in natural population of mahseer fish, Tor putitora (Hamilton, 1822)
Get PDFSkeletal deformities seriously relegate the biological performance of fish. The frequency of occurrence of different types of meristic variations and skeletal deformities were seen in the population of mahseer fish, Tor putitora, in two main reservoirs; Korang Stream, Islamabad and Dhobi Ghat Stream, Hassan Abdal. A total of ninety-five fish were caught randomly, forty-five from the unpolluted Korang Stream and fifty from the polluted Dhobi Ghat Stream by cast nets from February to July, 2009. Radiographs and dry skeletal preparation techniques were used to record meristic variations and skeletal deformities and describe various types and frequency of appearance. Deformities were studied under categories, Highest Frequency of Occurrence (HFO), Normal Frequency of Occurrence (NFO) and Lowest Frequency of Occurrence (LFO). In the deformed fishes, significant (p<0.001) anomaly was noticed in nineteenth to twenty second and forty one to forty third (p<0.05) vertebrae of the vertebral column. Deformities scoliosis (C2, 5.26%), platyspondyly (C5, 11.27%), and abnormal neural spine (TC25, 13.53) appeared to affect 70%, 60% and 50% of the deformed individuals respectively. This study concluded that skeleton deformities in T. putitora population in the laundry waste water of Dhobi Ghat Stream have relevance with detergent waste, as a possible causative agent
Short communication: Study on bioaccumulation of heavy metals (cadmium, nickel, zinc and lead) in the muscle of wels catfish (Silurus glanis) in the Anzali Wetland
Get PDFAfter entering aquatic ecosystems, heavy metals accumulate in the organs and tissues of aquatics including fish and finally enter the food chain. These heavy metals can enter the human body through eating contaminated fish. Absorbance values and accumulation of heavy metals in aquatics especially the fish depend on ecological conditions, physical, chemical and biological factors of water, the element type, and the physiological state of the aquatic (Oryan et al., 2010). Among aquatic ecosystems, wetlands and rivers are considerably important from the point of ecology. Rivers act as carriers of nutrients and non–nutrients and wetlands act as sinks for these substances. Now this effect will be more apparent if the wetland is an intermediary between a river and a static ecosystem. The Anzali Wetland is the type of ecosystem that embraces water from 11 rivers from one side and passes water into the Caspian Sea through a second outlet on the other side. The rivers passing through urban and rural areas and forests carry different types of organic matter, minerals, sediment, and industrial sewage (Taheri, 2013). The Anzali Wetland is one of the valuable wetlands registered in the Ramsar International Convention the contamination of which has become the main challenge for the people and officials during the past two decades (Khosravi, 2011)
Zonal diversity and community structure of invertebrate macrofauna in rocky intertidal area of Manora, Karachi, Pakistan
Get PDFRocky shores are important ecosystems that supports the wide variety of plants and animals and are characterized by the zonation of species. This three months study was conducted in order to recognize the community structure and zonal distribution of macro fauna at the Manora rocky shore. The sampling was done monthly for three months in the year 2014 at three tidal zones, i.e. High tide zone, Mid tide zone and Low tide zone and a zonal comparison of fauna was performed to identify the distribution pattern of species during pre-monsoon season. A total 1318 individuals belonged to 68 species were identified and counted. The phylum Mollusca was the most diverse phylum which represented by 43 species, followed by Arthropods (16 species), Echinoderms (4 species), Annelids (2 species), Cnidarians (2 species) and Porifera (1 species). The highest faunal diversity (H’= 1.429) was observed at the low tide zone, but the diversity of molluscs was high (H’=1. 329) at the mid tide zone
Effect of Oxadiazon Herbicide on Physiological, Biochemical and DNA Damage in Common carp (Cyprinus carpio)
Get PDFThis study conducted to evaluate the toxic effects of a widely used oxadiazon herbicide,on common carp (Cyprinus carpio) fingerling (15 g). The 96-h LC_50 was determined, and the growth performance, serum biochemical and hematological parameters, DNA damage of erythrocytes cells, as well as histopathological changes were also determined in fish exposed to sublethal concentrations (1, 1.5 and 2 ppm) of the herbicide for 30 days. The 96-h LC_50 to C. carpio was found to be 3.9 ppm. Weight gain (WG), specific growth rate (SGR) and condition factor (CF) were decreased, while food conversion ratio (FCR) increased in the exposed fish groups (P< 0.05). Erythrocytes cells of fish exposed to 1, 1.5 and 2 ppm of oxadiazon showed DNA damage (21.3%, 22.9%, and 28.4%, respectively), significantly higher than control group (p < 0.05). Moreover, exposure to oxadiazon significantly decreased WBC, RBC, Hb, Hct as well as serum albumin, glucose, and total protein levels, while serum ALP was significantly increased in the exposed fish groups
Histological, morphological and physiological studie on the ontogenic development of digestive tract in Alburnus chalcoides
Get PDFAlburnus chalcoides is a member of the Cyprinidae, which is considered as biologically, ecologically and economically important fish. Sampling of this fish was done randomly from the first day after hatching to pre-puberty at different intervals. The growth of this fish was investigated morphologically and histologically by Hematoxylin-Eosin staining method, and the secretion of gastrointestinal mucosal layers of the cells from carbohydrates was studied by histochemical analysis by periodic acid scavenging. To study the physiology of fish, its digestive enzymes were studied. Anatomical study on this fish showed that its digestive system consists of two major parts of the esophagus and intestines. In the early days of the digestive tract, it was a simple and simple tube in which mucosal secretions were not observed, but after the appearance of the Goblet cells, this activity began and a layer of neutral polysaccharide compounds was observed on the gastrointestinal tract. The presence of neutral polyunsaccharide secretions in the gastrointestinal mucosa has shown that it plays a role in the digestion and absorption of food and is important in protecting the epithelial layer of the digestive tract and passing food. In enzymatic studies, it was found that all enzymes had a significant difference in the level (p <0.05). The trypsin, chymotrypsin, and amino-peptidase enzymes have been shown to be more prominent in the two active start-ups, and the third and fourth weeks (entering the infant's age and adolescence). The alkaline phosphatase enzyme has a relatively stable trend and increased on the fifth day (mouth opening) and decreased slightly from week 4. Lipase and amylase also have a decrease trend, which is likely to be linked to a high protein diet of the animal. The start of active nutrition was increased, evolutionary characteristics of this fish were somewhat similar to other fish of the carp species, but there were also some differences
A Review on the Status of Small Pelagic Fish Resources in the Lingayen Gulf for the Year 2009-2013
Get PDFThis study was carried out to increase information on the status of small pelagic fish species status in Lingayen Gulf. The information includes the catch per unit of effort of fishing gears catching small pelagic and the current status of the dominant small pelagic fish species using the National Stock Assessment Program (NSAP) standard data gathering of fisheries catch and effort. The results showed that almost 50% of the total fish harvest in Lingayen Gulf are small pelagics and the commercial fisheries sector contributed the largest catch. The commercial fishing gears that mostly catch small pelagics are the Danish seine and Trawl with an annual catch per unit of effort ranging from 899 to 1,186 kg/day and 65.98 to 119.77 kg/day, respectively. The municipal fishing gears, bottom set gillnet and bottom set longline had an annual catch per unit of effort ranging from 7.04-42.95 and 7.19-13.30 kg/day, respectively. The dominant small pelagic species are Decapterus maruadsi, Decapterus macrosoma, Selar crumenophthalmus, Rastrelliger brachysoma, and Rastrelliger kanagurta. The dominant species caught by commercial fishing gears are mostly juveniles while the dominant species caught by municipal fishing gears attained maturity before they are caught. Exploitation ratio (E-values) of the dominant small pelagic species in this study exceed the optimum level of 0.5, an indication of overexploitation due to high fishing pressure
Assessment of the Tayabas Bay Fisheries
Get PDFThis technical paper discusses the results of the 10-year assessment (January 2004 to December 2013) of the fisheries of Tayabas Bay to determine the current status and level of exploitation and measure the effects of interventions introduced and implemented in the Bay and adjacent waters of Quezon and Batangas provinces. The trend of catch, effort and catch per unit effort from 2004 to 2013 showed an increase in catch attained by increasing effort, with fluctuating CPUE. The highest catch (24,622.9 MT) was attained in 2012. In 2013 the total production was 22,595.8 MT, an increase of 6.9% from the 2004 production. The fisherman’s density of 20/km for Tayabas Bay is low compared to other major fishing grounds like Lingayen Gulf, Guimaras Strait, and Manila Bay, but slightly higher than the estimates for Honda Bay and Ormoc Bay. The number of observed boat landings of all gears ranged from 13,746 MT in 2013 to 33,842 MT in 2005. The standardized annual estimated effort of the bottom set gillnet ranged from 2,199,589 MT to 7,194,394 MT. Most of the artisanal or municipal gears such as multiple hook and line (7 kg to 6 kg), drift gillnet (53 kg to 7 kg), and hook and line (9 kg to 5 kg) showed declining catch rates (CPUE). The bottom set gillnet, spear gun and surface gillnet, however, showed an increasing trend. Out of 16 species of fish analyzed, Cypselurus naresii, Rastrelliger faughni, Rastrelliger kanagurta, Decapterus tabl, Siganus canaliculatus and Upeneus sulphureus exhibited an E-value exceeding 0.5, which indicates overexploitation. As to the recruitment, nine species showed bimodal recruitment while seven species showed unimodal recruitment. There are seven species that have a mean length greater than their length at first maturity, which indicates that they have contributed to the recruitment process of their stocks before they are caught
Assessment of Fishery Resources in Lagonoy Gulf, Philippines
Get PDFThe Lagonoy Gulf is one of the largest and most important fishing grounds in the Bicol Region. It is endowed with commercially important finfish and is characterized by a multi-species and a multi-gear fishery. Assessment of marine fishery resources was done to determine the status of the gulf and to evaluate the effects of fishing activities in support to fisheries management. The data used were from 1998 to 2012. Consolidated results from the National Stock Assessment Program (NSAP) of Region V were collected along the determined landing sites in the provinces of Albay and Camarines Sur. The results showed that catch composition was dominated by small pelagics (43.83%), followed by large pelagics (42.18%), and demersal fishes (13.94%). It is also noted that 89-98% of the small pelagic species were caught below the length at first maturity and their vulnerability to several fishing gears resulted in growth overfishing. Analysis of the growth parameters indicated that the species were relatively fast-growing and short-lived – L∞ ranges from 24.92 for Indian scad (Decapterus russelli) to 52.81 for Frigate tuna (Auxis thazard); and a k value of 0.85 for the same species (A. thazard) to 1.34 for Indian mackerel (Rastrelliger kanagurta). The total mortality rate is high, ranging from 7.02, as manifested in Bigeye scad (Selar crumenophthalmus), to 13.13 for the Island mackerel (R. faughni). Lagonoy Gulf also suffers from overexploitation, in which computed E values were far beyond the optimum level of exploitation (E ranges from 0.69 to 0.84), which is the result of heavy fishing pressure in the area