Tiger Tooth Croaker Research Articles

From waste to nutrient: Proximate composition, morphological and elemental analysis of Tigertooth croaker (Otolithes ruber) fish bone

From waste to nutrient: Proximate composition, morphological and elemental analysis of Tigertooth croaker (Otolithes ruber) fish bone

First Molecular Identification and Subtyping of Blastocystis sp. in the Most Consumed Edible Marine Fish of Iran: A Foodborne Concern.

The presence of Blastocystis sp. is commonly observed in humans and different animals, displaying a wide range of genetic variations with the discovery of multiple subtypes (STs). However, the prevalence and distribution of these STs in edible marine fish and marine mammals remain uncertain. This study marks the first survey conducted in Iran and the second global molecular investigation to examine the occurrence and STs distribution of Blastocystis in various species of edible marine fish. This study screened 200 fresh intestinal contents from 10 well-known fish species (Narrow-barred mackerel, Indo-pacific king mackerel, Tigertooth croaker, Silver pomfret, Black pomfret, Longtail tuna, John's snapper, Blackspotted croaker, Four-finger threadfin, and Javelin grunter) in southern Iran, caught in the Persian Gulf. All collected samples were evaluated by microscopy and SSU-PCR methods. Based on both microscopy and PCR, the overall prevalence of Blastocystis sp. in evaluated fish species was 2% (4/200). In brief, Blastocystis sp. was reported from Narrow-barred mackerel [10% (2/20)], Silver pomfret [5% (1/20)], and Tigertooth croaker [5% (1/20)]. Interestingly, among infected fish species three zoonotic STs (ST1, ST2, and ST7) were identified. ST2 was the most predominant ST [50% (2/4)], followed by ST1 and ST7, one sample each [5% (1/20)]. Overall, the prevalence and STs distribution of Blastocystis in edible marine fish along with the possibility of its zoonotic transmission are still open to question and require extensive and more detailed studies.

Preparation and Characterization of Fish Protein Isolate from Tiger Tooth Croaker (Otholithus ruber) Obtained through PH Shift Method

Development of Fish Protein Isolate (FPI) from tiger tooth croaker (Otholithus ruber) fish meat using the pH shift method was carried out during this study. Tiger tooth croaker was used as raw material because of their abundance and comparatively low price. During the study, the physical characteristics and proximate composition of the fresh fish were analysed. The average length of fish was 19.95 cm and weighed 94.6 g. respectively. FPI treated at different pH treatments (2.5, 4, 7, 11.5 and 12.5) were analyzed for proximate composition, peroxide value and functional characteristics. In the present work, Tiger tooth croaker (Otolithes ruber) fish was found to be suitable for fish protein isolate production using acid or alkali processing and isoelectric precipitation. During storage at ambient temperature for 120 days in a 200 gauge LDPE pouch, Fish Protein Isolates treated at different pH treatments (2.5, 4, 7, 11.5 and 12.5) indicated an increase in moisture content, reduction in protein and lipid content and no significant reduction in ash content. The total protein content was specifically high for pH 7 followed by pH 12.5, 11.5, 4 and 2.5. The effect of different pH on PV of fish protein isolates showed increasing content with increasing storage. The functional properties such as water-holding capacity (WHC), oil-holding capacity (OHC), emulsifying capacity (EC) and foam measurements (Foaming capacity (FC) and foam stability (FS) exhibit high values for all the samples of fish protein isolates. The quality attribute of functional properties of all fish protein isolates samples showed a trend of decreasing during the storage of 120 days.

Selectivity of tigertooth croaker (Otolithes ruber) gillnet in fishing grounds of Oman Sea, Iran

Tigertooth croaker (Otolithes ruber) fishing has increased recently in southern Iran due to its economic value. In the present study, O. ruber gillnets with opening mesh sizes of 73, 85 and 90 mm were used to assess the selectivity of the nets. For this purpose, three panels each of commercial nets having mesh sizes of 73, 85 and 90 mm, were connected which formed an experimental net for sampling from January to May 2020. A total of 619 specimens of O. ruber were caught and the selectivity curves were plotted using the Sechin method. Results showed that the mean total lengths of O. ruber caught with mesh sizes of 73, 85 and 90 cm were, 26.89 ± 4.00; 35.33 ± 3.43, and 37.05 ± 3.32 cm, respectively. Considering the length at sexual maturity of 40 cm, it seems that gillnet with mesh size of 90 cm is the most suitable fishing net for catching the species. Keywords: Mesh size, Otolithes ruber, Sechin method, Selectivity curves

Characterization of the Iraqi Artisanal Marine Fisheries, Northwest of the Arabian Gulf

The study described the characteristics of the Iraqi artisanal marine fisheries in the northwest Arabian Gulf between January 2020 and December 2021. The study aimed to update knowledge on the fish landings of the artisanal marine fisheries in the study area. A total of 19,877 t of fish were landed in 2020 and 13,784 t in 2021. A Student’s t-test showed a significant difference between the species’ landings over the two years. The main species exploited were mullets (10.5%), threadfin bream (10.4%) and spotted leatherskin (8.4%) in 2020, whereas threadfin bream (14.2%), mullets (9.6%) and tigertooth croaker (8.3%) were mainly landed in 2021. Unfortunately, the contribution of river shad catches has dropped to lower levels over recent years, comprising 3.6-5.8% of the total landings during 2020-2021. Shrimps contributed 15.6 and 16.1% of the total landings during 2020 and 2021, respectively, and mixed fish contributed 11.8 and 15.3%, respectively. The trends of the landings of the main fish groups increased substantially from 2011 to 2021. Unfortunately, the contribution of river shad (T. ilisha) catches has dropped to lower levels over recent years, in contrast with the contributions of other species. Therefore, the study recommends the following management measures for the river shad stock: to protect the brood stock during the breeding season no fishing should be allowed in the Shatt Al-Arab River during the main spawning migration from May to June and small T. ilisha (<23.0 cm) should not be caught.

Effect of sage seed gum film incorporating Zataria multiflora Boiss essential oil on the storage quality and biogenic amine content of refrigerated Otolithes ruber fillets

The effect of an edible film based on sage seed gum (SSG) incorporating 3 % Zataria multiflora Boiss essential oil (ZEO) was investigated on the storage quality and shelf life of tiger-tooth croaker (Otolithes ruber) fillets during storage at 4 ± 1 °C compared to the control film (SSG film without ZEO) and the Cellophane. The SSG-ZEO film significantly decelerated microbial growth (evaluated by total viable count, total psychrotrophic count, pH, TVBN) and lipid oxidation (evaluated by TBARS) compared to the others (P ˂ 0.05). The antimicrobial activity of ZEO was the highest and the lowest on E. aerogenes (MIC: 0.196 μL/mL) and P. mirabilis (MIC: 0.977 μL/mL), respectively. E. aerogenes was identified as an indicator biogenic amine-producer in O. ruber fish at refrigerated temperature. The active film significantly lowered biogenic amine accumulation in the samples inoculated with E. aerogenes. A clear relationship was observed between the release of ZEO's phenolic compounds from the active film to the headspace and the reduction of microbial growth, lipid oxidation, and biogenic amine production in the samples. Consequently, SSG film containing 3 % ZEO is proposed as a biodegradable antimicrobial-antioxidant packaging to extend the shelf life and decrease the biogenic amine production in refrigerated seafood.

The relative condition factor and the Length-weight relationship of Otolithes ruber (Schneider, 1801) from the Iraqi marine waters

Relative condition factor (Kn) and the relationship of length-weight (L-WR) of Tiger Tooth Croaker fish Otolithes ruber (Schneider, 1801) were determined from January to August 2017 in the Iraqi marine waters. L-WR data of the fishes (females and males) were calculated separately. The mean of (Kn) for females and males was 1.04 and 0.999, respectively. The value of (Kn) for the females was minimum in January (0.953) and May (0.969), whereas the maximum value was noticed in March (1.06 for females and 1.058 for males). The b value was recorded at 2.9747 for the males and 3.0546 for the females. The results of the statistical t-test showed no significant differences between females and males (t= -0.6021, 1.222, p≤ 0.05, respectively).

Aspects of Population Dynamics of Tiger Tooth Croaker, Otolithes ruber (Bloch and Schneider, 1801) from Northwest Arabian Gulf, Iraq

The present study consists of the growth, mortality, relative yield recruit and virtual population analysis of tigertooth croaker, Otolithes ruber from Iraqi marine waters, northwest Arabian Gulf between February 2020 and January 2021. Analysis of population dynamics employed methods fitted in FiSAT II software using pooled length-frequencies. A total of 3835 individuals of O. ruber ranged from 17.0 to 60.0 cm have been collected. The exponent (b) of the length-weight relationship was found to be 2.755. The von Bertalanffy growth parameters (L∞ and K) were estimated as 68.5 cm and 0.36, respectively, while the growth performance index (Ø') was 3.228. The total mortality (Z) was calculated as 1.10, while the natural and fishing mortality rates were 0.69 and 0.41, respectively, and the current exploitation rate (Ecurrent) was 0.38. Fish were recruited to the fishery at a mean size of L50= 20.55 cm. The recruitment pattern of O. ruber was continuous throughout the year with two major peaks. The analysis of yield-per-recruit (Y/R’) indicates that the current exploitation rate was below the biological target reference points (E0.1 = 0.40 and Emax= 0.53), refer to the stock of O. ruber is underexploited. The 27 cm length group was more vulnerable to fishing and more harvested according to virtual population analysis. sLength at first capture was higher than the length at first maturity of the species in the region. For management purposes, more yields could be obtained by increasing the mesh sizes of the nets employed in the fishing of the species.

Stock assessment of the Tigertooth croaker, Otolithes ruber (Bloch & Schneider, 1801) from the commercial prawn trawl fishery by-catch in coastal Kenya

Commercial bottom prawn trawling has been reported to generate a higher proportion of by-catch of up to 70% in Kenya. The Tigertooth croaker, Otolithes ruber is one of the species caught in large quantities as commercial by-catch and also by artisanal fishers. This has led to growing concern that the species could be at risk of over-exploitation. The purpose of this study was to carry out a stock assessment of O. ruber. Stock assessment parameters were estimated using ELEFAN with the generic algorithm as included in the R package TropFishR. The length-converted catch curve and the length-based yield per recruit model were employed. The exploitation rate (F/Z = 0.71) indicates that the stock is overfished based on the length-converted catch curve. The current fishing mortality (F = 2.3) based on the catch curve is larger than the reference level ( = 1.1) based on the yield per recruit analysis and also indicates that the stock is overfished (= 2.09). To reverse the current trend of exploitation, improved management of the stock is required, which should include further studies on other by-catch species and the generation of data to capture the whole fishery for a better estimation of stock status.

Reproductive Biological Performance of Otolithes ruber (Bloch and Schneider 1801) in San Miguel Bay, Philippines

The tigertooth croaker, Otolithes ruber (Bloch and Schneider 1801), was studied to determine its reproductive biology characteristics for 34 months from March 2015 to November 2017. A total of 7,977 individuals were sampled and the measured total lengths (TL) ranged from 8.1 cm to 32.1 cm (16.70 ± 2.53 cm ) and 10.0 cm to 33.5 cm (17.95 ± 2.95 cm) for male and female, respectively. The length-weight relationship can be summarized as W = 0.00521 L3.18 and W = 0.00837 L3.01 for female and male, respectively. The length at first maturity of this species was determined to be 13.95 cm, which is smaller compared to other studies. The overall sex ratio of this species was 1:0.8, with males dominating the female sex (P < 0.05, X2 = 64.3). In addition, synchronized development of male and female gonads was observed. It was also verified that mature individuals were present all throughout the study period indicating that this species spawn continuously and the presence of juveniles during the sampling period indicated continuous recruitment. Mean monthly GSIs indicate July to November as the main spawning season of this species. The in-site occurrence of mature and juvenile stocks in the bay further implicates that San Miguel Bay is a nursery ground for this species. The fecundity varied between 3,420 to 422,100 with an average fecundity of 86,142 eggs. Lastly, the spawning potential ratio is still above the limit reference point (SPR = 0.36), indicating that the stock can still replenish their biomass.

Stock identification of tiger tooth croaker Otolithes ruber (Schneider, 1801) along the Indian coast using truss network analysis

The tiger toothed croaker Otolithes ruber (Schneider, 1801) of the family Sciaenidae is a demersal fish that contributes significantly to the marine landings of India. To identify stock units of O. ruber based on body shape morphometry, truss network analysis was carried out based on specimens collected from four selected locations, two each from east coast (Digha and Chennai along Bay of Bengal) and the west coast (Cochin and Ratnagiri along Arabian Sea) of India. A total of 20 truss distances along the fish surface, including head, mid body and posterior region were measured and transformed measurements were subjected to factor analysis and discriminant function analysis. The bivariate plot score of factor analysis indicating two distinct stocks on both the coasts may be the consequence of geographical isolation and different environmental conditions along the Bay of Bengal (east coast) and Arabian Sea (west coast). The Ratnagiri and Cochin population showed considerable mixing which indicated the presence of a unit stock along the west coast. However, existence of strong morphometric differentiation between Digha and Chennai populations indicated two separate spawning populations in the Bay of Bengal. In the cross-validation of Discriminant function analysis, the most well classified group was Digha population (97.85%). The present study suggests the possible existence of three stocks of O. ruber, one in west coast (Cochin and Ratnagiri) and two in east coast (Digha and Chennai) which can be considered while formulating effective management strategies for the species.

Quality enhancement in refrigerated tiger tooth croaker (Otolithes ruber) fillets using chitosan coating containing green tea extract

The effect of chitosan coating combined with green tea extract (GTE) on the quality of tigertooth croaker (Otolithes ruber) fillets including chemical, microbiological, texture, color and sensory properties during 16 days of refrigerated storage was investigated. The changes of color different were significantly retared, and the texture parameteres and sensory scores were significantly improved in tigertooth croaker coated by chitosan, GTE and chitosan combined with GTE, compared with the control. The coincidental lowered rate of increase total volatile base (TVB) content, thiobarbitoric acid (TBA), peroxide value (POV) and free fatty acid (FFA) were obtained in tigertooth croaker coated chitosan+GTE. Chitosan in combination with chitosan had higher inhibition on microbial groeth and yielded the tigertooth croaker with higher likeness, comapared with the other treatments. Therefore, fish coated with chtoas+GTE had the lowest losses in quality during refrigerated storage.

Population parameters and reproductive biology of Otolithes ruber (Bloch & Schneider, 1801) (Teleostei: Sciaenidae) in the northern Makran Sea

This study was conducted to determine some biological aspects of the tiger tooth croaker Otolithes ruber in the coastal waters of the northern Makran/Oman Sea. Monthly total length frequency data of O. ruber were collected by bottom gill-net and bottom trawl from August 2016 to August 2017. ELEFAN-I method in the software package FISAT-II was used to analyze of the length frequency data. The total length and weight relationship demonstrated that growth in this species is negative allometric. The asymptotic total length ( TL∞ ) was estimated as 60 and 65cm for males and females, respectively. The growth parameter K was calculated as 0.43 y -1 for males and 0.40 y -1 for females. The total mortality, natural mortality and fishing mortality rates were estimated as 1.85, 0.83 and 1.02 for males and 1.37, 0.77 and 0.60 for females. The exploitation rates were estimated at 0.44 for males and 0.55 for females. The sex ratio revealed that it was not a constant 1:1 throughout the year, with 58 % for females. The Gonado-Somatic Index (GSI) showed upswing trend from January to June, and the maximum GSI was 7.1±0.6 in April. The recorded result showed that the tiger tooth croaker can spawn all year round and have a spawning peak from April to June (spring season). The Lm 50 % was estimated at 43.3cm of total length.

Toxic metals in the muscle and liver of five main commercially-important fishes from the Persian Gulf, Southern Iran

The purpose of this study was to determine and compare the concentrations of six toxic metals (Cd, Pb, Fe, Cu, Zn, Mn) in the muscle and hepatic tissues of five commercially important fish species including narrow-barred Spanish mackerel, Scomberomorus commerson, Black pomfret, Parastromateus niger, Silver pomfret, Pampus argenteus, blackspot snapper, Lutjanus fulviflammus and Tigertooth croaker, Otolithes ruber, since they are very common in the household fish consumption. The fish samples were collected from three main landing areas along Bushehr and Hormozgan provinces during spring 2017. Our results indicated that lead concentration was higher than those of other measured heavy metals in all examined fish species, while it was an inverse situation for cadmium. We found that the concentration of the measured metals totally were higher in the liver than in muscle of all the examined fish. There was no significant intra-specific variation in metal concentration among the fish from the same species. Since it is very important to the consumer to choose between the species, we also detected the mean values of the metal concentration in the muscle of the relatively same aged species, sampled from same stations.

Examination of Relationship Between Mercury Rate with Zinc and Copper Changes in Muscle Tissue of Otolithes Rubber in Mahshahr Port—the Persian Gulf

The current study was conducted with the aim of examination of changes scope as well as correlation between mercury with zinc and copper in the muscle tissue of tigertooth croaker as one of the most consumed fish in the area (Mahshahr Port) and its comparison with available standards. The obtained results suggested that, total average concentration of Hg, Zn and Cu (mean ± SE) accumulated in the muscle tissue of tigertooth croaker (Otolithes rubber) are respectively equal to 1426 ± 113; 15999 ± 1045 and 2279 ± 94 (ngg–1) in summer as well as 955 ± 91; 13172893 and 1678 ± 178 (ngg–1) in winter. Comparison among accumulation rate of elements Hg, Cu and Zn in two seasons showed a significant correlation between two mentioned seasons for Zn and Hg. The correlation result indicates a positive significant relationship between zinc and copper and a descending significant relationship between Hg with Cu and Zn. Concentration of total mercury accumulated in the muscle tissue of tigertooth croaker (Otolithes rubber) within two seasons, summer and winter, are lower than standard limit (500 ngg–1) defined by WHO while it is higher than standard limit (300 ngg–1) estimated by USEPA. Due to high concentrations of Hg, the results can be a serious warning for consumption of this fish in Mahshahr region.

The relationship between otolith size and estimated age of tigertooth croaker (Otolithes ruber Bloch and Schneider, 1801) in Oman Sea, Iran

The relationships between somatic growth and otolith dimensions, otolith size to estimated age and growth parameters of the tigertooth croaker (Otolithes ruber) were investigated in 100 specimens (size range: 19.1–52.0 cm, total length) from the Oman Sea area, September 2014. All 100 otoliths were sectioned and determined by age. The oldest specimen was a 4.5-year-old female with a total length of 40.6 cm; the youngest specimen was also a female estimated at 1 year of age with a total length of 19.1 cm. The von Bertalanffy growth equation was estimated as Lt = 54.70 (1 − exp (−0.37 (t + 0.21))). Concluded was that there is a significant relationship between body size, otolith dimensions and estimated age of Otolithes ruber.

Short communication: Determination of total mercury in common carp, Cyprinus carpio, large scaled barb, Barbus grypus, tiger tooth croaker, Otolithes ruber and from surface waters in Khuzestan, Iran

Short communication: Determination of total mercury in common carp, Cyprinus carpio, large scaled barb, Barbus grypus, tiger tooth croaker, Otolithes ruber and from surface waters in Khuzestan, Iran

Effect of dehydration methods on physico-chemical and sensory qualities of restructured-dehydrated fish product

Development of restructured–dehydrated fish product enhances the shelf life as well as commercial value of fish. Along the similar lines, tiger tooth croaker (Otolithes ruber) mince was utilized in making restructured–dehydrated product (RDP). The effect of vacuum (VD), hybrid-solar (SD), and fluidized bed drying (FBD) on proximate composition, bio-chemical characteristics, and sensory acceptability of the RDPs was studied. Protein content of RDPs varied from 38.71 to 42.33%. The water activity of RDPs varied from 0.48 to 0.53, indicating shelf stability of RDPs. Lipid deterioration during drying was minimal as revealed by TBARS and FFA values. Rehydratability of FBD product was significantly (p ≤ 0.05) lower than others. Frying of RDPs yielded fish-cracker like products. Fried VD product was sensorially more acceptable than others. The present study could pave the way for development of a new class of fish meat based products wherein low value fish meat are utilized. Practical applications Fish meat is highly perishable and requires refrigerated and/or frozen storage. The restructured–dehydrated product provides a way to enhance the shelf life of fish meat. The low water activity associated with these products make them shelf stable. The RDPs could enhance the commercial value of fish meat. The RDPs obtained are highly convenient for preparation and could be consumed after frying or boiling or as an ingredient in fish curry.

Complete mitochondrial genome and the phylogenetic position of the tigertooth croaker Otolithes ruber (Perciformes: Sciaenidae)

In this study, the complete mitogenome of the tigertooth croaker Otolithes ruber was first determined. This mitogenome is 16,589 bp in length, and consists of 37 genes with the typical gene order and direction of transcription in vertebrates. The overall nucleotide composition is: 27.4% A; 29.1% C; 16.1% G and 27.4% T. Sizes of the 22 tRNA genes range from 66 to 74 bp. Four start codons (ACG, CTG, GTG and ATG) and three stop (AGA, TAG and TAA/TA/T) codons were detected in 13 protein-coding genes. In the Bayesian treebased on the complete mitogenomes of 18 species (including O. ruber) from the family Sciaenidae, all nodes were strongly supported. The phylogenetic results suggested that O. ruber was closed to the black-spotted croaker Protonibea diacanthus.

Environmentally induced tissue responses of hematopoietic system in abu mullet (Liza abu) and tiger tooth croaker (Otolithes ruber) from the Persian Gulf

The present investigation aimed to assess the possibility of using plasma levels of erythropoietin (EPO) hormone and tissue changes of hematopoietic organs as biomarkers of environmental pollution in abu mullet (Liza abu) and tiger tooth croaker (Otolithes ruber) collected from Musa Creek (northwest of the Persian Gulf). 120 L. abu and O. ruber were collected from five stations at the Musa Creek: Petrochemical, Ghanam, Doragh, Zangi and Patil stations. Blood samples were obtained from the caudal vein. Tissue samples were also taken from the spleen and head kidney, and tissue sections were prepared according to routine histological methods. The concentrations of Hg, Pb, Zn, Cu, and Cd were also measured in the sediment samples. The minimum level of EPO and the most severe tissue changes were determined in fish collected near a Petrochemical station. This station is adjacent to the Imam Khomeini Petrochemical Complex and receives highly contaminated effluents from this complex. The highest degree of contamination (Cd) also belonged to this station. The fish collected from the Patil station represented the highest EPO level and the least tissue changes. This station exhibited a lesser degree of contamination. Based on the results, there was a significant correlation between the plasma level of EPO hormone and the degree of environmental contamination.