The genetic diversity and the population structure of Barilius barna (Hamilton, 1822) wild population from the Teesta River were assessed through mtDNA cytochrome oxidase I (COI) sequence analyses. The haplotype and nucleotide diversity analyses revealed low level of genetic diversity in the B. barna wild populations, especially in the lower reaches of Teesta (Bholarhat). The genetic differentiation and gene flow between the two study sites were 0.08434 and 2.71, respectively. Tajima’s D , Fu and Li’s D and Fu and Li’s F analyses were used to assess population differentiation in the two study sites. Haplotype networking and phylogenetic analyses clearly distinguished the two populations from each other, as well as from other populations from other parts of the country. Nature and implications of the genetic and haplotype diversities among the populations are discussed. Phylogenetic analyses also indicated that the Gajoldoba population is genetically closer to north Indian river populations, than that to Bholarhat population.
通过mtDNA细胞色素氧化酶I (COI)序列分析，对Teesta河Barilius barna (Hamilton, 1822)野生种群的遗传多样性和种群结构进行了评价。单倍型和核苷酸多样性分析表明，巴尔纳白刺野生种群的遗传多样性水平较低，特别是在Teesta (Bholarhat)下游。两个研究点的遗传分化和基因流分别为0.08434和2.71。采用Tajima 's D、Fu and Li 's D和Fu and Li 's F分析对两个研究点的种群分化进行了评估。单倍型网络和系统发育分析清楚地区分了这两个群体，以及来自该国其他地区的其他群体。讨论了种群间遗传多样性和单倍型多样性的性质及其意义。系统发育分析还表明，加若尔多巴种群在遗传上更接近印度北部河流种群，而不是博拉哈特种群。
{"title":"Genetic diversity and population structure of Barilius barna (Hamilton, 1822) in the sub-Himalayan Dooars region of West Bengal, India through Mitochondrial Cytochrome Oxidase I Sequence analyses","authors":"Ajoy Paul, T. Mukhopadhyay, S. Bhattacharjee","doi":"10.22034/IJAB.V0I0.901","DOIUrl":"https://doi.org/10.22034/IJAB.V0I0.901","url":null,"abstract":"The genetic diversity and the population structure of Barilius barna (Hamilton, 1822) wild population from the Teesta River were assessed through mtDNA cytochrome oxidase I (COI) sequence analyses. The haplotype and nucleotide diversity analyses revealed low level of genetic diversity in the B. barna wild populations, especially in the lower reaches of Teesta (Bholarhat). The genetic differentiation and gene flow between the two study sites were 0.08434 and 2.71, respectively. Tajima’s D , Fu and Li’s D and Fu and Li’s F analyses were used to assess population differentiation in the two study sites. Haplotype networking and phylogenetic analyses clearly distinguished the two populations from each other, as well as from other populations from other parts of the country. Nature and implications of the genetic and haplotype diversities among the populations are discussed. Phylogenetic analyses also indicated that the Gajoldoba population is genetically closer to north Indian river populations, than that to Bholarhat population.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72473947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present study used the Ecological State Macrophyte Index (ESMI) and the multivariate statistical methods to assess the ecological status and the variation of macrophytes in a tropical wetland system. Six sites were selected from rehabilitated and non-rehabilitated areas of an urban tropical wetland and the water quality parameters (water pH, temperature, conductivity, total dissolved solids (TDS), dissolved oxygen (DO), visibility, biological oxygen demand 5 days after incubation (BOD 5 ), chemical oxygen demand (COD), nitrate, chlorophyll-a and total phosphorus concentrations), sediment quality parameters (pH, organic matter content, percentage sand, silt and clay content) and abundance of aquatic macrophytes were measured. Shannon Weiner diversity index, percentage vegetation under anthropo-pressure, macrophyte settlement rate and ESMI were calculated. Significant variations in the water and sediment quality parameters were observed and ten species of aquatic macrophytes were recorded. Salvinia melosta and Cypreus iria were recorded only from the non-rehabilitated sites. Although there was no significant difference in the percentage anthropo-pressure among study sites, the rehabilitated sites were displayed low anthropo-pressure. The sites in the non-rehabilitated area showed a significantly lower macrophyte settlement rate. ESMI and macrophyte abundance showed significant correlations with water quality parameters. Based on the results, it can be recommended that applications based on ESMI and multivariate statistics can be used to assess the ecological status of tropical wetlands.
{"title":"Macrophytes as indicators of the ecological status of a tropical rehabilitated wetland ecosystem: Application of multivariate statistics and Ecological State Macrophyte Index (ESMI)","authors":"Dimuthu Wijeyaratne, Aravinda Bellanthudawa","doi":"10.22034/IJAB.V0I0.675","DOIUrl":"https://doi.org/10.22034/IJAB.V0I0.675","url":null,"abstract":"The present study used the Ecological State Macrophyte Index (ESMI) and the multivariate statistical methods to assess the ecological status and the variation of macrophytes in a tropical wetland system. Six sites were selected from rehabilitated and non-rehabilitated areas of an urban tropical wetland and the water quality parameters (water pH, temperature, conductivity, total dissolved solids (TDS), dissolved oxygen (DO), visibility, biological oxygen demand 5 days after incubation (BOD 5 ), chemical oxygen demand (COD), nitrate, chlorophyll-a and total phosphorus concentrations), sediment quality parameters (pH, organic matter content, percentage sand, silt and clay content) and abundance of aquatic macrophytes were measured. Shannon Weiner diversity index, percentage vegetation under anthropo-pressure, macrophyte settlement rate and ESMI were calculated. Significant variations in the water and sediment quality parameters were observed and ten species of aquatic macrophytes were recorded. Salvinia melosta and Cypreus iria were recorded only from the non-rehabilitated sites. Although there was no significant difference in the percentage anthropo-pressure among study sites, the rehabilitated sites were displayed low anthropo-pressure. The sites in the non-rehabilitated area showed a significantly lower macrophyte settlement rate. ESMI and macrophyte abundance showed significant correlations with water quality parameters. Based on the results, it can be recommended that applications based on ESMI and multivariate statistics can be used to assess the ecological status of tropical wetlands.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76404167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bianca Sofia F. Abiñon, Boniver S. Camporedondo, Esther Mae B. Mercadal, Kathryn Marie R. Olegario, Evan Marie H. Palapar, Chrisian Wilfred R. Ypil, Antonio E. Tambuli, Christopher. Lomboy, J. Garces
This study documents microplastics (MPs) in the top three commercially sold fishes viz. Auxis rochei , Rastrelliger kanagurta and Chanos chanos in major public markets of Cebu Island, Philippines. MPs were found in the gastrointestinal tracts (FGIT) and quantified and characterized according to size, type, and color. In general, nine (97.3%) of 81 FGIT samples contained 635 total pieces of MPs with size ranging 0.01 to 0.50 and 1.00 to 2.00 mm. Transparent microfibers (91%) were the most predominant MPs, with blue (48%) as the most common MP color observed, followed by red (39%), black (8%) and white (5%). Chanos chanos proved to be the most susceptible fish to MP ingestion with a mean average of 11.6 pieces per individual fish, followed by A. rochei with 6.6 pieces, and R. kanagurta with 5.3 pieces. The results indicated that MPs were ubiquitous and high in commercially sold fishes in major public wet markets of Cebu Island, Philippines. The ingestion of fishes is of primary concern as a route of human exposure to MPs because they filter a large volume of seawater and are typically eaten whole without gut removal. Further study is needed on the potential consequences of MPs to aquatic populations to assess comprehensive exposure integrating multiple sources and routes.
{"title":"Abundance and Characteristics of Microplastics in Commercially sold fishes from Cebu Island, Philippines","authors":"Bianca Sofia F. Abiñon, Boniver S. Camporedondo, Esther Mae B. Mercadal, Kathryn Marie R. Olegario, Evan Marie H. Palapar, Chrisian Wilfred R. Ypil, Antonio E. Tambuli, Christopher. Lomboy, J. Garces","doi":"10.22034/IJAB.V8I6.874","DOIUrl":"https://doi.org/10.22034/IJAB.V8I6.874","url":null,"abstract":"This study documents microplastics (MPs) in the top three commercially sold fishes viz. Auxis rochei , Rastrelliger kanagurta and Chanos chanos in major public markets of Cebu Island, Philippines. MPs were found in the gastrointestinal tracts (FGIT) and quantified and characterized according to size, type, and color. In general, nine (97.3%) of 81 FGIT samples contained 635 total pieces of MPs with size ranging 0.01 to 0.50 and 1.00 to 2.00 mm. Transparent microfibers (91%) were the most predominant MPs, with blue (48%) as the most common MP color observed, followed by red (39%), black (8%) and white (5%). Chanos chanos proved to be the most susceptible fish to MP ingestion with a mean average of 11.6 pieces per individual fish, followed by A. rochei with 6.6 pieces, and R. kanagurta with 5.3 pieces. The results indicated that MPs were ubiquitous and high in commercially sold fishes in major public wet markets of Cebu Island, Philippines. The ingestion of fishes is of primary concern as a route of human exposure to MPs because they filter a large volume of seawater and are typically eaten whole without gut removal. Further study is needed on the potential consequences of MPs to aquatic populations to assess comprehensive exposure integrating multiple sources and routes.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84624982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fish and fisheries have long been subject of art works of ancient Persians, Egyptians and Chinese. Art has a variety of dimensions and perspectives associated with nature/environment including marine or freshwater bodies. Following the idea of linking art, fish and fisheries and the marine environment, in this study, we used local set-net fishing known as Moshta as a traditional fishing gear at the coastal area of Bandar Abbas, Iran to present emotional state and concept of repeatability. The Moshta fishing (i) repeats almost every day, (ii) stimulates emotions, (iii) brings deaths to fishes, (iv) supplies food to peoples and birds, and (v) contributes to the economy of local families. Hence, there is always a reproducibility creation in this man-made fishing gear. This process in a worthy way to bring lights to the creation of different links between fish and fisheries from one hand and art in the other hand.
{"title":"Moshta fishing: A link between fish and fisheries and art","authors":"S. Moradi, Leila Sarvandi","doi":"10.22034/IJAB.V0I0.1028","DOIUrl":"https://doi.org/10.22034/IJAB.V0I0.1028","url":null,"abstract":"Fish and fisheries have long been subject of art works of ancient Persians, Egyptians and Chinese. Art has a variety of dimensions and perspectives associated with nature/environment including marine or freshwater bodies. Following the idea of linking art, fish and fisheries and the marine environment, in this study, we used local set-net fishing known as Moshta as a traditional fishing gear at the coastal area of Bandar Abbas, Iran to present emotional state and concept of repeatability. The Moshta fishing (i) repeats almost every day, (ii) stimulates emotions, (iii) brings deaths to fishes, (iv) supplies food to peoples and birds, and (v) contributes to the economy of local families. Hence, there is always a reproducibility creation in this man-made fishing gear. This process in a worthy way to bring lights to the creation of different links between fish and fisheries from one hand and art in the other hand.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86080318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nanoparticles are widely used in removing bacteria from water and sewage. This study evaluated the effect of graphene/silver nanocomposite on the removal of coliform from a dairy effluent. The composition was synthesized and its properties were determined using different techniques such as SEM, XRD and FTIR. The effects of various factors, including pH, adsorbent dose and contact time on coliform removal from solution were studied. Antimicrobial activity of the nanocomposite was examined by pour plate method in a VRBL medium. After preparing the VRBL medium from the sewage effluent, 1 mL of nanocomposite solution and 1 mL of bacterial suspension containing 9×10 4 CFU/mL were added into each of the plates. According to the results, the rate of silver ion release is faster as pH decreases, which naturally results in the increase of disinfection. Moreover, a higher percentage of removal occurred with an increase in contact time and nanocomposite dose due to higher exposure to nanoparticles and their higher penetration into bacterial cell membrane. Therefore, nanoparticles produced by this method exhibited good antibacterial activity, so that 100% of bacteria were eliminated at a nanocomposite concentration of 3.4 g/L and pH=5, after 90 min.
{"title":"Removal of coliform bacteria from dairy wastewater using graphene-silver nanocomposite","authors":"M. Bahri, A. Hamidian, Yu Zhang, Min Yang","doi":"10.22034/IJAB.V8I6.1025","DOIUrl":"https://doi.org/10.22034/IJAB.V8I6.1025","url":null,"abstract":"Nanoparticles are widely used in removing bacteria from water and sewage. This study evaluated the effect of graphene/silver nanocomposite on the removal of coliform from a dairy effluent. The composition was synthesized and its properties were determined using different techniques such as SEM, XRD and FTIR. The effects of various factors, including pH, adsorbent dose and contact time on coliform removal from solution were studied. Antimicrobial activity of the nanocomposite was examined by pour plate method in a VRBL medium. After preparing the VRBL medium from the sewage effluent, 1 mL of nanocomposite solution and 1 mL of bacterial suspension containing 9×10 4 CFU/mL were added into each of the plates. According to the results, the rate of silver ion release is faster as pH decreases, which naturally results in the increase of disinfection. Moreover, a higher percentage of removal occurred with an increase in contact time and nanocomposite dose due to higher exposure to nanoparticles and their higher penetration into bacterial cell membrane. Therefore, nanoparticles produced by this method exhibited good antibacterial activity, so that 100% of bacteria were eliminated at a nanocomposite concentration of 3.4 g/L and pH=5, after 90 min.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81453541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Thuridilla indopacifica Gosliner, 1995 (Sacoglossa, Plakobranchidae) is a rare species in the Sacoglossan nudibranch that only reported from the South Africa and Western Australia. This study records T. indopacifica from the Gulf of Oman for the first time showing its expansion to the northwest of Indian Ocean.
{"title":"First record of the Thuridilla indopacifica Gosliner, 1995 (Sacoglossa, Plakobranchidae) from the Gulf of Oman, Iran","authors":"Y. Fatemi, M. Taherizadeh, A. Shahdadi","doi":"10.22034/IJAB.V8I6.1015","DOIUrl":"https://doi.org/10.22034/IJAB.V8I6.1015","url":null,"abstract":"Thuridilla indopacifica Gosliner, 1995 (Sacoglossa, Plakobranchidae) is a rare species in the Sacoglossan nudibranch that only reported from the South Africa and Western Australia. This study records T. indopacifica from the Gulf of Oman for the first time showing its expansion to the northwest of Indian Ocean.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76498819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recently an article entitled “A unique sex chromosome system in the Knifefish Gymnotus bahianus with inferences about chromosomal evolution of Gymnotidae” has presented the chromosomal structure of a Gymnotus population inhabiting the Contas River basin, eastern Brazil. We believed that the examined specimens were misidentified as G. bahianus . Hence in this work we examined the used material of the above-mentioned work and found that they belong to the species G. interruptus . This conclusion was based on a careful examination of materials from both species (type, recently collected, and additional materials). Gymnotus interruptus can be distinguished from G. bahianus by possessing a colouration pattern in which conspicuous dark obliquely oriented bands occur under lateral line at entire extension of trunk.
{"title":"Misidentification of Gymnotus interruptus (Gymnotiformes: Gymnotidae) leads to erroneous karyotype addressing","authors":"F. Rangel-Pereira, F. Ottoni","doi":"10.22034/IJAB.V0I0.1019","DOIUrl":"https://doi.org/10.22034/IJAB.V0I0.1019","url":null,"abstract":"Recently an article entitled “A unique sex chromosome system in the Knifefish Gymnotus bahianus with inferences about chromosomal evolution of Gymnotidae” has presented the chromosomal structure of a Gymnotus population inhabiting the Contas River basin, eastern Brazil. We believed that the examined specimens were misidentified as G. bahianus . Hence in this work we examined the used material of the above-mentioned work and found that they belong to the species G. interruptus . This conclusion was based on a careful examination of materials from both species (type, recently collected, and additional materials). Gymnotus interruptus can be distinguished from G. bahianus by possessing a colouration pattern in which conspicuous dark obliquely oriented bands occur under lateral line at entire extension of trunk.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77869163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pre-spawning reproductive behavior on the mudflat surface was reported previously for the mudskipper, Periophthalmus modestus , but it remains unknown how a pair spawns and fertilizes eggs within the spawning chamber of a burrow. In this study, we recorded reproductive behaviors from burrow entry of a pair to the departure of a female. In those cases, where spawning was suspected from a drastic reduction in the distension of the female’s belly (N = 4), the female remained inside a burrow for 240-350 min without coming out onto the mudflat surface. In contrast, the male often but irregularly emerged from the burrow. In one case, a second male entered a burrow 169 min after the burrow entry of a female, resulting in her desertion from the burrow without spawning. During burrow cohabitation of the pair, burrow openings were often clogged by mud from inside. After the female left the burrow, the male remained inside the burrow for variable periods. Then, the male guarded the burrow for about one week. Upon termination of the burrow guarding, the male began excavating a new burrow near the previous one or repaired the burrow that he had guarded. A hypothesized scenario is proposed for the reproduction of this species for the further investigation.
{"title":"Burrow residence of males and females of the mudskipper Periophthalmus modestus during reproduction","authors":"H. V. Mai, K. Soyano, A. Ishimatsu","doi":"10.22034/IJAB.V8I6.923","DOIUrl":"https://doi.org/10.22034/IJAB.V8I6.923","url":null,"abstract":"Pre-spawning reproductive behavior on the mudflat surface was reported previously for the mudskipper, Periophthalmus modestus , but it remains unknown how a pair spawns and fertilizes eggs within the spawning chamber of a burrow. In this study, we recorded reproductive behaviors from burrow entry of a pair to the departure of a female. In those cases, where spawning was suspected from a drastic reduction in the distension of the female’s belly (N = 4), the female remained inside a burrow for 240-350 min without coming out onto the mudflat surface. In contrast, the male often but irregularly emerged from the burrow. In one case, a second male entered a burrow 169 min after the burrow entry of a female, resulting in her desertion from the burrow without spawning. During burrow cohabitation of the pair, burrow openings were often clogged by mud from inside. After the female left the burrow, the male remained inside the burrow for variable periods. Then, the male guarded the burrow for about one week. Upon termination of the burrow guarding, the male began excavating a new burrow near the previous one or repaired the burrow that he had guarded. A hypothesized scenario is proposed for the reproduction of this species for the further investigation.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73660699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Rafiee, C. Saad, M. Kamarudin, M. Ismail, K. Sijam
The role of different weight groups of the red tilapia on nutrient uptake of the feed supply was investigated in a recirculating aquaculture system (RAS). Five weight groups of red Tilapia viz. 20 (20±0.0), 40 (39.7±0.44), 80 (80.38±0.41), 120 (113.62±1.92), and 180 (177.67±1.81) g in triplicate treatments were designed. The studied nutrients uptake rates by red tilapia were significantly different ( P <0.05) between the treatments. It was found that the red tilapia could assimilate 11.46% Fe, 13.43% Zn, 6.81% Mn, 3.55% Cu, 26.81 Ca %, 20.29% Mg, 32.53% N, 7.16% K and 15.98% P content of the feed supply during three weeks culture period. The specific growth rate (SGR) and food conversion ratio (FCR) indices showed significant differences ( P <0.05) between the treatments. The highest growth rate was recorded in 120 g treatment. It was concluded that nutrient requirements of the red tilapia are changed in different growth stages.
{"title":"Feed-nutrients uptake rates of different weight groups of red tilapia (Oreochromis sp.) in a recirculating aquaculture system","authors":"G. Rafiee, C. Saad, M. Kamarudin, M. Ismail, K. Sijam","doi":"10.22034/IJAB.V8I5.410","DOIUrl":"https://doi.org/10.22034/IJAB.V8I5.410","url":null,"abstract":"The role of different weight groups of the red tilapia on nutrient uptake of the feed supply was investigated in a recirculating aquaculture system (RAS). Five weight groups of red Tilapia viz. 20 (20±0.0), 40 (39.7±0.44), 80 (80.38±0.41), 120 (113.62±1.92), and 180 (177.67±1.81) g in triplicate treatments were designed. The studied nutrients uptake rates by red tilapia were significantly different ( P <0.05) between the treatments. It was found that the red tilapia could assimilate 11.46% Fe, 13.43% Zn, 6.81% Mn, 3.55% Cu, 26.81 Ca %, 20.29% Mg, 32.53% N, 7.16% K and 15.98% P content of the feed supply during three weeks culture period. The specific growth rate (SGR) and food conversion ratio (FCR) indices showed significant differences ( P <0.05) between the treatments. The highest growth rate was recorded in 120 g treatment. It was concluded that nutrient requirements of the red tilapia are changed in different growth stages.","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79751195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marine forests are experiencing a severe decline in many Mediterranean areas. One of the major causes of the loss of the canopy-forming species is the overgrazing by herbivorous fishes. In the present study, the status of Treptacantha ballesterosii and Carpodesmia zosteroides populations was checked in two areas located along the central-eastern sector of Sicily. In addition, impact of herbivorous fishes, native or alien, on canopy-forming species was realized during monitoring of fish communities. It was observed that T. ballesterosii and C. zosteroides populations are in regression, particularly T. ballesterosii . Probably, the growth of this latter species may be limited by a strong herbivores’ pressure. During the monitoring period, the highest number of fish species has been observed at the depths where there are T. ballesterosii thalli. Moreover, an expansion of Sparisoma cretense populations has been observed that seems to be more competitive than the other herbivorous fish Sarpa salpa . Furthermore, the parrotfish has been observed several times in the bathymetric range where there is T. ballesterosii . Therefore, it may be hypothesized that in these areas the herbivorous fish which mostly hinder the development and growth of T. ballesterosii is S. cretense .
{"title":"Assessment of grazing impact on deep canopy-forming species in the western Ionian Sea, Central Mediterranean","authors":"G. Marletta, A. Lombardo","doi":"10.22034/IJAB.V8I5.882","DOIUrl":"https://doi.org/10.22034/IJAB.V8I5.882","url":null,"abstract":"Marine forests are experiencing a severe decline in many Mediterranean areas. One of the major causes of the loss of the canopy-forming species is the overgrazing by herbivorous fishes. In the present study, the status of Treptacantha ballesterosii and Carpodesmia zosteroides populations was checked in two areas located along the central-eastern sector of Sicily. In addition, impact of herbivorous fishes, native or alien, on canopy-forming species was realized during monitoring of fish communities. It was observed that T. ballesterosii and C. zosteroides populations are in regression, particularly T. ballesterosii . Probably, the growth of this latter species may be limited by a strong herbivores’ pressure. During the monitoring period, the highest number of fish species has been observed at the depths where there are T. ballesterosii thalli. Moreover, an expansion of Sparisoma cretense populations has been observed that seems to be more competitive than the other herbivorous fish Sarpa salpa . Furthermore, the parrotfish has been observed several times in the bathymetric range where there is T. ballesterosii . Therefore, it may be hypothesized that in these areas the herbivorous fish which mostly hinder the development and growth of T. ballesterosii is S. cretense .","PeriodicalId":36975,"journal":{"name":"International Journal of Aquatic Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79283914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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