Exposure of Fishery Resources to Environmental and Socioeconomic Threats within the Pantanal Wetland of South America | Author : Cleber JR Alho* and Roberto E Reis | Abstract | Full Text | Abstract :The huge Pantanal wetland, located in the central region of South America, mainly in Brazil, formed by the Upper Paraguay River Basin, comprising 150,355 km² (approximately 140,000 km² in Brazil), is facing environmental and socioeconomic threats that are affecting fish populations and fishery resources. The Paraguay River and its tributaries feed the Pantanal wetland, forming a complex aquatic ecosystem, harboring more than 260 fish species, some of them with great subsistence and commercial values to regional human communities. Sport fishing is also preeminent in the region. The natural ecosystems and the increasing human population that depend on them are at risk from a number of identified threats, including natural habitat disruptions and overfishing. Fishing catches have been decreasing, as has the size of captured fish. Riverine vegetation, which is periodically flooded during the high-water season, forming feeding and reproductive grounds for some fish species, has been affected by deforestation and other impacts. Conversion of natural vegetation for human use and wild fires are severe and have become part of the annual cycle of ranch owners. Flooding dynamics have been threatened by infrastructure, including small hydroelectric plants on the riverheads. |
| Miscellaneous Marine Fishes Caught under PFZ and Non-PFZ Realm off Ratnagiri Coast, Maharashtra State, India | Author : Tingote RS and Mane UH* | Abstract | Full Text | Abstract :Potential Fishing Zones connote where Chlorophyll Concentration and Sea Surface Temperature together constitute better environment for the healthy growth of fish and food abundance. Fishing was done in both within and outside PFZ zones after validating PFZ advisory in time and firsthand information is also collected from the fish catch in different gears by following generated PFZ advisory and feedback in the standard format developed by INCOIS. Within PFZ means potential and good number of fish catch is obtained as compared to outside PFZ means fishing is done away 2-3km without using PFZ advisory. Identical boats were selected at the same time from the same landing centers going one in within and other for outside PFZ fishing boats separately carried fishing operations in accordance with the PFZ area provided by the satellite. The availability of food is an important factor that controls their occurrence, abundance and migrations in the sea. Sea Surface Temperature (SST) is the most easily observed environmental parameter and is quite often correlated with the availability of fish, especially pelagic fish. A better understanding of the behavior and dynamics of fish populations including their response to environmental and anthropogenic pressures is essential for effective management of marine fisheries. In spite of the vast scope and potentials for development of marine fishery along Ratnagiri coast, significant and tangible progress needs to be achieved so far through INCOIS-DOD which is leading to benefit the fishermen community in obtaining high fi sh catch with less efforts and time and fuel saving from PFZ, still much is needed to work based on a few drawbacks and gaps as seen (a) lack of sufficient understanding PFZ, (b) failure to recognize the PFZ during fishing, (c) lack of modernizing or upgrading the mechanized boats, and (d) little infrastructure and equipment in fishing. The INCOIS-DOD Mission activities should be thoroughly and critically is followed both by fishermen and their societies on the Ratnagiri coast region for which the expansion of this Mission and extension of research activities. The successful validation on PFZ advisory from the three fi sh landing centers were conducted during the study tenure. |
| Comparison of the Crossbreeding Effects of Three Mandarin Fish Populations and Analyses of the Microsatellite Loci Associated with the Growth Traits of F1 Progenies | Author : Qingkai Zeng, Chengfei Sun, Junjian Dong, Yuanyuan Tian and Xing Ye* | Abstract | Full Text | Abstract :Cross breeding with different populations might lead to heterosis and enhance the genetic diversity of the resulting offspring. In this study, three populations of mandarin fish (Siniperca chuatsi), including two cultured (A and B) and one wild population (C), were used to construct three pure groups (A?×A?, B?×B?, C?×C?) and six crossbred groups (A?×B ?, A?×C?, B?×A?, B?×C?, C?×A?, C?×B?). Growth performance was compared among all combinations, and 11 microsatellites were used to analyze the genetic diversity of the resulting offspring and identify correlations associated with growth traits (body weight, total length, and body height). The best growth performance values associated with the growth traits were detected in the progeny of the inbred A?×A? group. The A?×B? and A?×C? F1 exhibited relatively high increases of growth in all crossbreed combinations, whereas the F1 of C?×B? exhibited lower growth performance. Cross combinations that used male fi sh from the A population displayed significant growth advantages. Analysis of genetic diversity showed that the expected heterozygosity (He) of the F1 of all combinations were greater than 0.5 except A?×C?, B?×A?, and A?×A?. The results of association analyses indicated that seven microsatellite loci, est21, w19521, sch14, sc90, est43, w19517, and sc01 were associated with the targeted growth traits. This result laid a good foundation for further breeding selection of mandarin fish using population selection and molecular marker-assisted selection. It also would provide more reliable guidelines for breeding selection of other fish species. |
| Dose Dependent Treatment with Boric Acid Induces More Changes in the Sperm Cells of Endangered Anatolian Trout Salmo Rizeensis | Author : Filiz Kutluyer*and Mehmet Kocabas | Abstract | Full Text | Abstract :The aim of this study was to test the usefulness of boric acid for endangered Anatolian trout Salmorizeensis sperm. Activation media was supplemented with boric acid (0.5, 1, 2, 3, 4 and 5 mM). Sperm motility and duration were determined in sperm samples. In addition, fertility and hatching rate were examined. Our data indicated that addition of boric acid (3 mM) to activation media was increased the percentage and duration of motile sperm, fertility and hatching rate in endangered Anatolian trout (S. rizeensis). On the other hand, the motility rate decreased with increasing the concentration of boric acid (p<0.05). In particular, a remarkable increase was observed after concentration 3 mM. Consequently, sperm quality was affected by quantitative changes different concentrations of boric acid and the best results were obtained at concentration 3 mM. |
| In Vitro Effect of Zinc: Evaluation of the Sperm Quality of Endangered Trout Salmo Coruhensis and Rainbow Trout Oncorhynchus Mykiss and Fertilizing Capacity | Author : Mehmet Kocabas and Filiz Kutluyer* | Abstract | Full Text | Abstract :This study was intended to reveal the usefulness of Zinc in endangered trout Salmo coruhensis and rainbow trout Oncorhynchus mykiss sperm. Spermatozoa were activated in sperm motility-activation solutions (NaCl, 0.3%; NaHCO3, 1%) containing the Zinc [Control (0), 0.5, 1, 2, 3, 4 and 5 mM]. The percentage and duration of motility, fertility and hatching rate were determined in sperm samples. Our results indicated that the percentage and duration of motility, fertility and hatching rate increased when activation solution containing NaHCO3 was supplemented with 1 mM Zinc in rainbow trout (O. mykiss). On the contrary, motility rate in endangered trout (S. coruhensis) was increased by Zinc compared to control group. The percentage and duration of motility, fertility and hatching rate were affected by increasing concentrations of Zinc in endangered trout (S. coruhensis) and rainbow trout (O. mykiss) (p<0.05). In conclusion, sperm quality was affected by quantitative changes different concentrations of Zinc and the best results were obtained from a concentration of 1 mM for rainbow trout. |
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