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International Journal of Aquatic Biology - Volume:4 Issue: 1, Feb 2016

International Journal of Aquatic Biology
Volume:4 Issue: 1, Feb 2016

  • تاریخ انتشار: 1395/01/27
  • تعداد عناوین: 8
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  • Lotfi Bensahla Talet, Ahmed Bensahla Talet, Zitouni Boutiba Pages 1-10
    Population dynamic parameters of red mullet, Mullus barbatus (n=592) caught by trawlers operating in Arzew Gulf (Algeria) in the western Mediterranean were studied. Samples were collected between February 2013 and January 2014. Females ranged from 10.9-23.2 cm in total length and 12-149.2 g in weight whereas males length was comprised between 12.6 and 19.7 cm and weight between 21.3 and 99.9 g. The relationship between length and weight was W=0.00167L2.842 (r²=0.850). Growth parameters of the von Bertalanffy equation were: L∞=20.89 cm, K=0.66 year-1, t0=-0.143 year for males, while for females: L∞=250.9 cm, K=0.6 year-1, t0=-0.015 year. Estimates of total (Z), natural (M) and fishing (F) mortalities were: 1.58, 0.8 and 0.79, respectively and the estimated exploitation ratio 0.5 indicating that the resource is being exploited at its limit in this area. The virtual population analysis of M. barbatus by VIT software showed that the number of recruits per year was estimated at 4447304.6 individuals, balanced total biomass was estimated at 168 486 tons, the gains are represented by recruitment 51.71 tons (30.69%) and growth 116.76 tons (69.31%), losses are represented by natural mortality 98.48 tons (58.45%) and fishing mortality 70 tons (41.55%). The current yield per recruit was estimated to Y/R=15.74 g and maximum sustainable yield can be reached by increasing the current fishing effort to stabilize it at MSY=17.91 g.
    Keywords: Exploitation, Fishery, Mortality, Weight, length relationship, von Bertalanffy
  • Fateme Moslehi, Masoud Sattari, Alireza Shenavar Masouleh Pages 11-16
    An eight-week experiment was carried out to determine the effects of dietary Pediococcus pentosaceus as probiotic on the body composition and gut microbiota of Siberian sturgeon, Acipenser baerii. A total of 180 fish with mean body weight of 143±0.01g were randomly distributed into 12 200L fiberglass tanks as four treatments with three replicates, including groups fed with diet containing 2×107, 2×108 and 2×109 CFU g-1 of P. pentosaceus and probiotic-free as control group. Body composition of treatment groups was not influenced by P. pentosaceus except for fat and moisture. The bacteria had a significant colonization in the intestine of fish fed with supplemented diet with P. pentosaceus. High level of acid lactic bacterial load was found in the treatment fed with highest amount of the probiotic i.e. 2×109 CFU g-1. The results showed that application of P. pentosaceus has positive effect on the body composition and intestinal microflora of the A. baerii.
    Keywords: Sturgeon, Probiotic, Intestine microflora, Body composition
  • Saroj Kumar Ghosh, Padmanabha Chakrabarti, Shrabani Barun Pages 17-24
    The disposition and cellular organization of the endocrine pancreas were studied in three species of freshwater teleosts viz., Labeo bata (Hamilton, 1822), Sperata aor (Hamilton, 1822) and Chitala chitala (Hamilton, 1822) using histological techniques. In L. bata, the endocrine pancreas tissues were mainly distributed in the adipose tissue among the intestinal coils and adjacent to extrahepatic bile duct, while in S. aor and C. chitala, the endocrine pancreas predominantly attached with wall of the stomach along with exocrine pancreatic part. Histological analysis demonstrated that the endocrine components of all the three species were enclosed in a thin capsule provided with different cells, interspersed with blood sinuses. The cytoarchitectural analysis showed that in L. bata, β cells were usually arranged in groups while α cells were often interspersed with blood vessels. In S. aor and C. chitala, the rounded or oval α cells were usually arranged either in groups or scattered to the islets periphery and β cells which were densely granulated and typically stained with Aldehyde fuchsin (AF), Romies azan (RA) and Mallory’s triple (MT) were observed in the central areas of the islets and intercalated with blood vessels. The δ like cells were founded at a low frequency and intermingled with β cells and exhibited moderate cytoplasmic granules in L. bata, S. aor and C. chitala. Despite being the subject of extreme controversy, the nature and function of different islet cells were discussed.
    Keywords: Histoarchitecture, Endocrine pancreas, Labeo bata, Sperata aor, Chitala chitala
  • Alireza Pourkhabbaz, Borhan Mansouri, Mohammad Hosein Sinkakarimi, Ghasem Rajaei, Robabeh Vajdi Pages 25-30
    The purpose of the present study was to determine the acute toxicity (LC50) of HgCl2 and CuSO4 in Caspian roach (Rutilus caspicus) and CuSO4 in Caspian kutum (Rutilus kutum). The Caspian roach LC50 values for HgCl2 at 24, 48, 72, and 96-hrs of exposure, were 0.64, 0.61, 0.42, and 0.28 mg L-1, respectively, and for CuSO4 were 11.55, 5.08, 2.49, and 1.47 mg L-1, respectively. The Caspian roach LC50 values for CuSO4 at 24, 48, 72, and 96-hrs of exposure, were 5.31, 4.17, 3.20, and 2.25 mg L-1, respectively. The results of this study showed that the toxicity of HgCl2 is higher than that of CuSO4 for the studied species. The mortality decreased with time, and most of the deaths were occurred during the first 24 hrs.
    Keywords: Toxicity, LC50, Static bioassay, Fish
  • Soroor Mirghiyasi, Hamid Reza Esmaeili, Mohsen Nokhbatolfoghahai Pages 31-42
    This study presents the first details on morphological and histological characteristics of gonads, gonadal development stages and reproductive index of the Persian loach, Oxynoemacheilus persa (Heckel, 1847), an Iranian endemic species. Sampling was done from April 2010 to April 2011 using electrofishing device and a total of 196 individuals were collected. The gonads of specimens were removed, their sexes determined and then were fixed in 10% formalin solution after checking their morphology and measuring their weights, lengths and widths. Based on the size, shape and weight of the gonads, degree of occupation of the body cavity, presence or absence of ripe oocytes or milt, diameter of the oocytes in the ovary, and histological observations, five stages of sexual maturation in females and four stages in males were determined by macroscopic and microscopic criteria. The results of the gonadal stages showed that the O. persa spawns in the middle of spring and these stages were correlated to the gonado-somatic index (GSI).
    Keywords: Reproduction, Gonad morphology, Gonad histology, Sexual maturation, Gonado, somatic index
  • Muyideen Owonire Lawal, Ademola Zaid Aderolu, Oluwaseun Olasunkanmi Aarode, Bolanle Moriamo Seriki, Timothy O. Alonge Pages 43-50
    This study evaluated the effects of 0.25% activated charcoal added to sesame seed meal (SSM) in partial replacement of soybean meal (SBM) of juvenile Clarias gariepinus diet on growth and haematological parameters for 70 day experimental period. Six experimental diets were formulated as: control diet 1 (100% SSM without activated charcoal), control diet 2 (100% SSM plus 0.25% activated charcoal), diet 3 (50% SMB% SSM), diet 4 (50% SBM% SSM.25% AC), diet 5 (30% SBM% SSM) and diet 6 (30% SBM% SSM.25AC). The inclusion of activated charcoal recorded significant improvement in mean weight gain, mean feed intake, specific growth rate (SGR), protein intake (PI) and protein efficiency ratio (PER). The control diet 2 recorded the highest values for growth and nutrient utilization parameters while diet 5 recorded the least values for these parameters. The best values for mean weight gain (65.33±5.57 g), specific growth rate (2.56±0.12% / day) and feed conversion ratio (0.71±0.05) were recorded in fish fed control diet 2 while the worst values (41.30±3.82 g, 1.92±0.11% / day, and 1.07±0.07, respectively) for these parameters were observed with diet 5. However, haematological parameters did not differ significantly across the diets. Thus, from this study 0.25% activated charcoal could favorably be added to the feed of C. gariepinusfor optimum performance without any adverse effect on the health status of the fish.
    Keywords: Soybean meal, Growth performance, Activated charcoal, African catfish
  • Hamed Mousavi, Sabet, Keyvan Abbasi, Saber Vatandoust, Soheil Eagderi Pages 51-56
    Paracobitis vignai is a Nemacheilid loach endemic to the Sistan basin. It occurs in Helmand River and its related reservoirs in Sistan-va-Baluchistan Province in southeastern Iran and probably in Afghanistan. This species is currently endangered due to habitat loss or degradation, damming and droughts. Therefore, this paper reviews the available data on taxonomy and distribution of P. vignai, provides its morphometric features, and recommends actions for its conservation.
    Keywords: Endemic species, Sistan basin, Conservation, Iran
  • Hamed Kolangi Miandare Pages 57-67
    The isolation-by-distance theory states that the genetic differentiation between individuals raised by increasing geographic distance. Therefore, this study tested this hypothesis for Garra rufa, a freshwater fish species of Iranian inland waters, from six rivers located at the different distances in Tirgis basin. For this purpose, eight variable microsatellite loci were applied to identify geographic-based population structure of G. rufa. From 240 fish of six populations, 102 alleles were found with a mean number of 11.625 to 13.250 alleles. Heterozygosity was ranged 0.567-0.638 in six studied populations. Moreover, a significant deviations from Hardy-Weinberg were found in the studied populations. Unweight pair group analysis indicated that the six studied populations could be divided into four major clusters. The results revealed a fairly high level of genetic variation in the microsatellite loci within six studied populations. Wright’s fixation index (Fst) ranged between 0.013-0.044 indicating little genetic differentiation between populations. Within this range, however, we found a strong positive relation between Fst and geographical distance lending support to the isolation-by-distance theory.
    Keywords: Genetic diversity, Microsatellite, Doctor fish, Tigris Basin, Iran