Day 1 :
Keynote Forum
Quenton Dokken
Gulf of Mexico Foundation, Inc., USA
Keynote: Wild caught plus cultured fisheries products – Can the demand be met without destroying the resource, the environment, and the dependent socioeconomic systems?
Time : 10:30-11:00
Biography:
Quenton Dokken is the President/CEO of the Gulf of Mexico Foundation, Inc. and past Associate Director of Center for Coastal Studies of Texas A&M University-Corpus Christi. As a Research Scientist, he has conducted studies in “The socioeconomics of Texas fisheries, the biological productivity of natural and artificial reefs, the ecology of ichthyoplankton in a bay system and the nutritional requirements of cultured species”. Today, he is working with fishers, processors, wholesalers, retailers, and chefs to maximize efficient utilization of seafood products.
Abstract:
Outlaw fishing, slave ships, overfished stocks, conflicting management strategies, conflict between harvest groups, disease in intensive culture conditions, eutrophication through the use of enriched feeds, habitat destruction, weakened gene pools, climate change, growing demand, etc., the state of fisheries globally is not on a course of sustainability. Recognizing the importance of fisheries, economically, culturally and nutritionally, this portends conflict and hardship in the future. Knowing these threats, what can we do to redirect the fisheries industry to a sustainable future? The solution lies in coordinated collaboration between governments, resource management agencies, law enforcement, scientists, fishers, wholesalers, processors, retailers, chefs, consumers, and environmentalists. The solution also requires commitment by vested interests to the mission of effective management, the goal to reach sustainability and the strategy to achieve the goal. This is not a new understanding or idea, yet to date this collaboration has not been adequately accomplished and the fisheries industries continue to sail toward extinction. We see the threat and know the causes; can we assert the will power to impose the solution?
Keynote Forum
Huarong Guo
Ocean University of China, China
Keynote: In vitro cell culture of marine invertebrates: Problems and prospectives
Time : 11:20-11:50
Biography:
Huarong Guo has completed her PhD from Institute of Oceanology, Chinese Academy of Sciences, China and Post-doctoral studies from University of South Carolina, USA. She set up her own lab in College of Marine Life Sciences, Ocean University of China in 2011 and focus on “The development of continuous cell lines from the adult tissues and early embryos of economically important penaeid shrimps”. She has been an executive council member of Shandong Society for Cell Biology (China) since 2014 and published more than 26 papers in reputed journals.
Abstract:
In vitro cultured animal cells have provided us a very powerful tool to study virology, molecular biology, cell biology and immunology, etc. In contrast to mammalian, fish and insect where the development of a variety of cell lines has become routine, the establishment of cell lines from marine invertebrates has been encountered with big obstacles, and there is no single established cell line from marine invertebrates reported. This talk reviews the advances, problems and prospectives in the field of marine invertebrate cell cultures.
- Fish Pathology & Physiology | Freshwater Fisheries | Fish farms: Planning a new one | Fisheries Statistics
Chair
Quenton Dokken
Gulf of MexicoFoundation,Inc., USA
Co-Chair
Huarong Guo
Ocean University of China, China
Session Introduction
Xinzhong Wu
Qinzhou University, China
Title: Developmental and evolutionary immunity of marine molluscan animals: Immune diversity and evolution
Biography:
Xinzhong wu is currently a Professor of Qinzhou University and Dean of Ocean College, Qinzhou University, China. He is a Scientific Researcher of Marine Mollusc Disease and Mollusc and Fish Immunology. He has published 46 papers in English reputed journals and more than 60 papers in Chinese. Now, he is the 11th council members of Asian Fisheries Society; Chair of workshops, symposia and training committee of AFS; Councilor of Federation of Asian Biotech Association; member of steering committee of World Oyster Society; Councilor of China Society of Fisheries and; Councilor of Chinese Society of Oceanography. He served as an Editorial Board Member in several journals of international and China.
Abstract:
Recently relevant findings from molluscs expanded our traditional concepts in the field of innate immunity, namely from simple and homogeneous invertebrate immune system to the sophisticated and diversified innate immune system to host defense against pathogens, which include the effect of molecular diversity or increased abundance on immune diversity of molluscs, pathways that involved in molluscan immunity and how mollusk and pathogen interact at the molecular level. In particular the completion of related complete genome sequence from mollusc species gives the opportunity to examine the evolution of gene families, sequence divergence from different components of the innate immune system and the origins of some novel immune-related genes and their families in evolution. Here, we detailed some of the examples among these mollusc models to emphasize the diversities of the immune genes, their families and the diversified responses of innate immunity. We sought to discuss the drives or evolutionary dynamics of differences currently within the innate immune system from the present study existing in fact. In addition, we put forward the necessity of studying on comparative immune diversity with different invertebrate models.
Ana Carolina de Azevedo Mazzuco
Federal University of Sao Paulo, Brazil
Title: Scales of variability in supply side ecology of a marine invertebrate: Challenges to stock-recruitment forecasting
Biography:
Ana Carolina de Azevedo Mazzuco has completed her PhD from University of São Paulo. She is currently a young Researcher and Environmental Consultant at Deep Blue. She is also an extended member of IMAR/Federal University of São Paulo. Her studies focus on “Benthic-pelagic coupling in rocky shore invertebrates”. She has more than 10 years of experience in scientific field. She has published two papers in reputed journals and has presented her work at important scientific meetings.
Abstract:
The state of exploited populations is a function of the stock and recruitment, which are regulated by larval supply and settlement rates. Environmental conditions causes supply side processes to vary in space and time at several scales challenging recruitment forecasting. In this study, we assessed the relationship between supply side processes in Perna perna, a commercial rocky shore bivalve, and meteorological-oceanographic conditions at different spatial-temporal scales. This study was conducted at South Brazilian Bight, a subtropical region influenced by upwelling and meteorological fronts. Larval supply, settlement and recruitment rates were measured monthly, weekly and daily from 2012 to 2013, with local (km) and regional (10-100 km) resolutions. Meteorological-oceanographic conditions were described by physical forcing (wind speed and direction, wave and sea level height), chlorophyll-a concentration and sea surface temperature. Results show that the strength of the relationship between supply side processes and environmental conditions depends on the temporal scale. The degrees of correlation between ecological and environmental variables were low and specific larval supply mechanisms could not be identified. Local contrasts were responsible for most of the variability in supply side processes; however, regional coincidences blocked recruitment along the region. These results suggest that processes at both scales have similar power when regulating recruitment, affecting community to species levels. This study highlights the importance of scales of variability when predicting marine stocks.
Ozlem Ablak Gurbuz
Texas State University, USA
Title: Reverse effect of dams on fish populations in Turkey
Time : 12:40-13:05
Biography:
Ozlem Ablak Gurbuz has completed her PhD at Gazi University, Turkey and Post-doctoral studies at University of Massachusetts, USA. She is a Research Scholar at Texas State University in San Marcos. She has published more than seven papers in reputed journals.
Abstract:
Turkey, located between Europe and Asia, has six main and 25 sub-river basins hosting 153 endemic fish species out of 368 freshwater fish. One of main activity on rivers in Turkey has been constructions of dams. As of the beginning of 2015, there are 857 dams in operation and 600 dams under construction across Turkey. Dams on rivers would change overall temperature regimes, sediment transport and biotic homogenization. Besides, dams restrict migratory fish species and might cause loss of aquatic fauna and flora particularly endemic fish species. For this reason, dams are one of the greatest global threats for freshwater biodiversity. 51% of freshwater fish species of Turkey has been reported as critically endangered (CR) and 32% of that endangered (EN). Therefore, an environmental flow in any stream is vital for fish species. This paper will focus on effects of dam constructions on freshwater fish species in Turkey and underline importance of environmental flow in a stream for fish species.
Seher Dirican
Cumhuriyet University, Turkey
Title: The latest status of aquaculture in sivas on Central Anatolia of Turkey
Biography:
Seher Dirican is an Assistant Professor in Fisheries Department at University of Cumhuriyet, Turkey. He has published more than 15 papers in international journals. His research interests include “Fisheries, aquaculture and environment, water quality, aquatic organisms, pollution and limnology”. He is an Editor and Reviewer in various international journals.
Abstract:
Aquaculture is the fastest growing food producing industry in the world. Aquaculture production will certainly continue to be one of the most viable methods to supply population’s increasing demands of high quality animal proteins. Sivas is a city in central Anatolia of Turkey. The city, which lies at an elevation of 1278 m in the valley of the Kızılırmak river, is a moderately sized trade center and industrial city, although the economy has traditionally been based on agriculture. This study was carried out to determine the latest status of aquaculture in Sivas. Intensive aquaculture in Sivas is mainly related to fresh water aquaculture, which shows the best expansion prospects. In Sivas, rainbow trout (Oncorhynchus mykiss Walbaum, 1792) is the most common fish species cultured in both land based raceways and cages. According to current official figures, 46 rainbow trout farms are present in the Sivas and their total production capacity is about 5541 tons in 2015. Aquaculture has a effect on the environment as other agricultural activities. The target of aquaculture rises in a style that does not damage the environment. Therefore, environmentally friendly production and monitoring of environmental effects of aquaculture is required for sustainable aquaculture in Sivas.
Ogunremi J B
Federal University Wukari, Taraba State, Nigeria
Title: Information sources and accessibility among fisher folks in Ese - Odo and Ilaje local government areas of Ondo State, Nigeria
Biography:
Ogunremi J B completed his PhD from University of Ibadan, Nigeria and has specialization in Fisheries and Aquaculture Extension. He is a Senior Lecturer and Pioneer Head at Department of Fisheries and Aquaculture, Federal University Wukari, Taraba State, Nigeria. He is a senate member of the University, has served and still serving as Chairman or member of various committees in the University. He is a member/coordinator of different professional associations. He is involved in teaching, research and community service and has presented research papers at conferences. He has also published more than 26 papers in reputed journals and edited conference proceedings and has been serving as Reviewer for local and international journals of repute.
Abstract:
A multistage random sampling procedure was employed to select two local government areas (Ese-odo and Ilaje), six fishing communities and 12 fisher folks from the study area to get a sample size of 144. A structured questionnaire and scheduled interview was used to collect data from the respondents. Data were analyzed with the use of descriptive statistic such as frequency counts and percentages. Chi-square was used to test relationships between the variables. The results showed information need of fisher folk on fishing gear maintenance 92.4%, weather 88.2%, modern fish capture method 86.8%, sources of micro credit 86.8% and 57.6% had access to information. Extension agents 13.2% and friends 11.8% were the major sources of information among the fisher folk. The chi-square analysis indicated that no significant association existed between accessibility and information source among fisher folk on extension agents (χ²=0.37, p>0.05), research institute (χ²=0.18, p>0.05), non-governmental organization (χ²=0.12, p>0.05), radio (χ²=0.26, p>0.05), television (χ²=0.08, p>0.05) and friends (χ²=0.19, p>0.05), It is recommended that government should maximally utilize all available information sources to reach the fisher folk to boost protein supply through artisanal fisheries.
Biography:
Maryam Akhoundian has completed her MSc from Tarbiat Modarres University of Tehran. After 9 years spent on research and teaching in universities, she compeleted her PhD from Khorramshahr University of Marine Science and Technology. She is an Assistant Professor in Marine Biology at Marine Science of University of Mazandaran, Iran.
Abstract:
The Roach, Rutilus rutilus caspicus, is a potential for commercial aquaculture in Iran. One of the most significant constraints limiting commercial production of Roach is the lake of a reliable supply of eggs and larvea. A narrow window of annual spawning prevents year-round availability of juveniles for grow out. The present study reports the use of photoperiod and temperature manipulation to alter the time of spawning in female R. rutilus caspicus and increase availability of larvae which is so mean to sustainable aquaculture. Mature female Roach were maintained 70 days under a simulated natural light (NL) and 16L/8D, 11L/13D and 9L/15D photoperiod regimes. Water temperature was adjusted on 14, 20 and 24ºC. Reproductive development was monitored by histological analysis of gonadal biopsies and plasma level of 17β-stradiol and 17α-hydroxy progestron as main sexual steroids were investigated as well. The results showed that, follicle growth and spawning in females were advanced approximately two months by exposure to the long day regime. This research also suggested that in the process of oocyte maturation of Roach, photoperiod appeared to be more affective than temperature for even in the lowest experimental temperature (14°C), the fish exposed to the long photoperiod had earlier maturity and spawning in comparision to natural light regime. These finding suggest that photoperiod manipulation can be used to alter the reproduction cycle in Roach and control the supply of eggs for commercial aquculture.
Liberato V. Laureta
University of Philippines Visayas, Philippines
Title: The dynamics, ecology, production and economic aspects of exploited populations of Oriental angelwings in the coastal waters of Central Negros Occidental, Philippines
Biography:
Liberato V Laureta is a Professor of College of Fisheries and Ocean Sciences at University of the Philippines Visayas. He completed his MS in Aquaculture at University of the Philippines, the premier learning institution of the country, and PhD in Life Sciences (Marine Biology) at University of Liverpool in England. Being involved in research for many years, he published several papers in international and national peer-reviewed journals. His greatest contribution to science is the publication of the book entitled “Compendium of the Economically Important Seashells in Panay, Philippines” which has become reference for students of marine biology, fisheries, aquatic fauna or similar areas of study starting from high school to college. Fortunately, this book had been awarded as outstanding book in the field of Natural Science by two prestigious science institutions in the country. Currently, his research work focuses on “The development of suitable technologies for the hatchery and nursery operations of the Philippine green mussel Perna viridis”.
Abstract:
The people of Central Negros Occidental, Philippines pride themselves with the very important mollusk resource in their coastal waters, the oriental angel wing (Pholas orientalis) or locally called diwal. Being considered as a delicacy due to its succulent, sweet juicy taste, unique flavor, and likewise believed to have possessed an aphrodisiac element in it, this species has become a major source of livelihood for numbers of fishermen in this area. However, there is a need to have baseline information as basis for developing management schemes in order to either restore or conserve and protect the P. orientalis population towards sustainable production and utilization. This research paper presents results of the field survey conducted on the ecology, population status and distribution of the marine resource in the six municipalities comprising Central Negros. Likewise information on the history of the angel wing industry, its seasonality and yearly production including marketing which were gathered through interviews are presented. The prospects of the angel wing industry to prosper lie on the joint collaboration of the concerned divers, coastal residents, barangay and local officials, traders, the academe, funding agencies and the national government. Some fishery management strategies are presented and discussed in this paper, which are important to effectively manage the resource in this area toward sustainability.
Ma. Eugenia Vega-Cendejas
CINVESTAV-IPN, Unidad Mérida, Mexico
Title: Spatial variation of demersal fish communities in the Platform and Channel of Yucatan
Time : 15:40-16:05
Biography:
Maria Eugenia Vega-Cendejas has been working on taxonomy and ecology of fish communities, contributing to biodiversity knowledge in protected areas and coastal -marine ecosystems. She has used the fish resources on impacted ecosystem as bio-indicators of the environmental quality, and studied trophodynamics and energy fluxes in coastal ecosystems considering fish association (structure) and the use of the ecosystem (function).
Abstract:
The nature semi-closed of the Gulf of México, together with its oceanographic pattern and freshwater discharges, provide a rich region considering biodiversity. However, the demersal fish community structure is almost not known, even that this great ecosystem has been continuously impacted by oils spills and over exploitations of fishery resources. The present study was developed to evaluate spatial variation of the demersal fish community, considering depth gradient in the platform and channel of Yucatan in southern Gulf of Mexico. Fish sampling was realized in 18 stations with an oceanographic ship using a shrimp trawl at 99 m as average depth. A total of 130 species were recorded, where Serranidae family was the most diverse (10 species), following in importance Paralichthyidae (eight species), Sparidae and Triglidae with seven species each. The most representative specie considering density was Syacium papillosum (12.4% del total). The highest density and biomass were recorded in the Channel of Yucatan due to the abundance of Sphoeroides spengleri and Syacium papillosum. Considering fish composition and abundance, three groups of stations were associated. Fish abundance relationship to three ranges of depth was not significant. However, in the superior stratum (<50 m), the highest species richness (103) was obtained; while at 100 m, the diversity (3.35 bits) was recorded. By contrast, at the highest depth (>200 m), the lowest species richness (41) and diversity (2.9 bits) were found. These results are the first ones conducted in the region, contributing to the management of the large ecosystem of the Gulf of Mexico in order to stop further decline in biodiversity. This information is also a line base to evaluate the changes in demersal fish community originated by oil spills and other stressors related with climate change.
Cristelle Tiwo Tsapla
Dschang University, Cameroon
Title: Effect of ice storage on the textural and rheological properties of proteins from freshwater fish: Cyprinus carpio
Biography:
Cristelle Tiwo is a Researcher in Department of Food Science and Biotechnology, Dschang University, Cameroon. She is specialized in Nutrition and Food Security. She was a Research Associate in Food Protein and Fishery Transformation. She has visited many research institutes in Asia such as CIFT, CIFE and College of Fishery in Mangalore, India. She is implicated in many publications and is now writing a chapter in a scientific book.
Abstract:
The properties of proteins from fresh fish common carp (Cyprinus carpio) meat and its suitability for the preparation of fish sausage have been evaluated. The protein solubility of fish meat in high ionic strength buffer was 77.16%. The dynamic visco-elastic behavior of fish meat in the temperature range of 25-90oC using controlled stress rheometer revealed ability to form strong gel network which was further confirmed by frequency sweep test. The gel strength and texture profile analysis (TPA) of fish sausage prepared from Cyprinus carpio revealed elastic properties. The ice storage stability of fish as judged by physical, chemical, microbiological and sensory parameters was found to be 15 days. Gel strength of ice stored fish reveals that decreasing trend at 0th day of prepared gel strength was 668.2 gm.cm and at the end of the 15th day ice storage fish mince prepared gel was 398.70 gm.cm.
Sogbesan Olukayode Amos
Modibbo Adama University of Technology, Nigeria
Title: Performance of Clarias gariepinus (Burchell) fed solid state fermented groundnut (Arachis hypogeal) shell supplemented diets
Biography:
Sogbesan Olukayode Amos has completed his PhD from University of Ibadan, Nigeria in 2007 and Post-doctoral studies from Central Institute of Freshwater Aquaculture, Bhubaneswar, India in 2012. He is a Senior Lecturer and immediate past Head of Department of Fisheries at Modibbo Adama University of Technology, Yola. He has more than 50 peer reviewed journals to his credit and he is an Editorial Board Member of reputed journals.
Abstract:
This research study was carried out to evaluate the effect of feeding fermented groundnut shell supplementary diet on the biochemical performances of Clarias gariepinus fingerlings. Semi flow through consist of 15 plastic bowls were used and 10 Clarias gariepinus fingerlings (mean weight (3.00±0.05 g) per plastic bowl, each in triplicate. Five treatment bowls were fed experimental diets containing 40.00% crude protein supplemented with fermented groundnut shells. Diet one- unfermented groundnut shell (control diet), diet two- 12 hours fermented groundnut shell without potash, diets three, four and five- fermented groundnut shells with potash at fermentation time of 12, 24, and 48 hours respectively. Data generated were subjected to ANOVA at p<0.05. The results of the experiment showed that the best feed conversion ratio (FCR) was also recorded in fish fed diet five (0.43). Results showed that there were increase in the blood parameters of Clarias gariepinus fed fermented groundnut shell supplemented diets compared to the control diet but were statistically different (p<0.05). Highest packed cell volume of 22.23%, white blood cell 15.50 x 103, red blood cell 9.35 x 106 and haemoglobin 10.35 g/dl were recorded in fish fed diet five. All blood parameters obtained were between the ranges of recommended fish blood. It is concluded that using fermented groundnut shell as supplementary feed on Clarias gariepinus shows a slight increase in the hematological parameters compared with the control diet but it has no negative effect on the health status of the studied fish. However, diet five can be used as feed in aquaculture to enhance fish health, survival and growth performance.
- Fish Capture and Fishing Gears | Pelagic Fisheries | Deep Water & Demersal Fisheries | Shellfish Fisheries
Chair
Xinzhong Wu
Qinzhou University, China
Co-Chair
Sogbesan Olukayode Amos
Modibbo AdamaUniversityof Technology, Nigeria
Session Introduction
Xinzhong Wu
Qinzhou University, China
Title: Response of the oyster Crassostrea ariakensis environmental stress under experimental conditions
Biography:
Xinzhong Wu is currently a Professor at Qinzhou University and Dean of Ocean College, Qinzhou University China. He is a Scientific Researcher in Marine Mollusc Disease, and Mollusc and Fish Immunology. He has published about 46 papers in English reputed journals and more than 60 papers in Chinese. Now, he is the 11th council member of Asian Fisheries Society and the Chair of Workshops, Symposia and Training Committee of AFS, the Councilor of Federation of Asian Biotech Association, member of Steering Committee of the World Oyster Society, Councilor of the China Society of Fisheries and Councilor of the Chinese Society of Oceanography. He served as Editorial Board Member in several journals of China and international journals.
Abstract:
The oyster Crassostrea ariakensis is an important bivalve species cultured in southeastern China. In the year of 2004, farmed oyster C. ariakensis in Hailing Bay, GuangDong province of China had suffered from mass mortalities in autumn and winter. When analyzing the weather data of this area, we found it has been exposed to severe aridity. In this study, by pathological observation, the haemocytes in oyster were found present less than normal. By studying the haemocytes producing Reactive Oxygen Species (ROS) and percentage of haemocytes apoptosis of oyster cultured in higher temperature and salinity, it was found that the oysters in higher salinity and temperature could produce more ROS and present more haemocytes apoptosis than those cultivated in lower temperature and salinity. Subsequently, some cloned oyster innate immunity related genes and transcription level under different salinity and temperature were investigated by real-time PCR. It was found the gene galectin was extremely significantly up-regulated and met was very distinctly down-regulated from the oyster cultivated in higher salinity and temperature. It can be inferred that the higher temperature and salinity could induce oyster C. ariakensis producing more ROS, and then ROS could result in oyster haemocytes apoptosis and impairing the innate immunity and finally leading oysters to fatal death.
Tao Wang
Beihai Fengshun Aquaculture Company, China
Title: The design and application of the new anti-wave steel fish cage
Biography:
Tao Wang has completed his Bachelor of Landscape Architecture degree from Nanjing Agriculture University, China in 2010. This achievement led him to be able to transfer with two years of course credits to University of Adelaide, Australia in his Bachelor of Architectural Studies. He completed his Bachelor of Architectural degree and Master of Architecture degree from University of Adelaide in 2014. He is the Vice-President of Beihai Fengshun Aquaculture Company in Beihai, Guangxi, China. Currently, he works on “Developing new techniques for fish cages”.
Abstract:
The new innovative design of the anti-wave steel cage has the potential to supersede a large variety of currently used wooden cage for fish farming industry in Beihai, Guangxi, China. The key feature of the cage design is its square steel frame, as the use of the large tubular steel not only provides the sufficient buoyancy and structural support, but more importantly the space between two square units can create effective stable walkways for workers. Additionally, the new cage is equipped with a bait casting machine for feeding fish. From 2013 to 2015, we conducted Trachinotus ovatus farming experiments by using these new cages. During the test, the growth rate of Trachinotus ovatus greatly improved and equipped auto bait casting machines have saved both labor costs and feeding costs in comparison to traditional fish farming methods. In addition, these cages have undergone extreme weather conditions, including the typhoon rammasun in 2014. Typical wooden cages in the same area that were affected during the typhoon crisis suffered from various levels of damages, whereas the new steel cages remained rigid, unharmed and in working condition. This has proved that the advantages of using the new innovative steel cage have outstanding ability to withstand such extreme weather conditions in China’s south sea.
Fave Bulus Filli
Federal University Wukari, Taraba State, Nigeria
Title: Projection of table size fish prices in aquaculture business in Adamawa state, Nigeria
Biography:
Fave Bulus Filli has completed his PhD from Modibbo Adama University of Technology, Yola-Nigeria. He is the Director of Agricultural Economics and Teacher in his own field of specialization, having interest in Community Development and Research. He has published more than 10 papers in reputed journals and has been serving as an Editorial Board Member of repute.
Abstract:
The study was on projection of price of fish in Adamawa State, Nigeria. The objectives of the study were to determine the profitability of fish farming and examine the projected price to be received by fish farmers on a long-run equilibrium in Adamawa State, Nigeria. Data were collected using structured questionnaire administered to 150 fish farmers using snowball sampling techniques and were analyzed using descriptive statistics, net income analysis and Markov chain processes. The profitability analysis revealed a gross margin and net income of N155.81 and N135.22 per kg respectively, while N0.32 was gained for every naira spent. The projection showed that price above N500 will be received on every Kg of fish. It is concluded that fish farming is profitable with a higher price on table sized fish at the long run. The study recommends that youth and women should be engaged in fish farming, inputs should be supplied at subsidized rate and credits facilities should be provided to fish farmers to give a good platform to the farmers.
Adeosun Festus Idowu
Federal University of Agriculture, Abeokuta, Nigeria
Title: Fish species composition, distribution and abundance and gillnet fisheries in Ikere Gorge, Nigeria
Biography:
Adeosun Festus Idowu has completed his PhD from Federal University of Agriculture Abeokuta, Ogun State, Nigeria. He has held different offices within and outside the institution. He has served as Head of Department (HOD) in the absence of the HOD. He has also served in different capacity of the Academic Staff Union of the university as Vice to the Chairman and then as Chairman among others. He is currently a member of Community Based Farmers Society (COBFAS). He has published more than 25 papers in reputed journals.
Abstract:
Overfishing is a major problem in fisheries as fishermen without adequate knowledge of the composition, distribution and abundance of fish species continuously fish in water bodies using various fishing gears thereby depleting the stock. Here, we carried out the ecological study of Ikere Gorge between January 2004 and December 2005 to assess the fish resources of the Gorge and the gear commonly used by fish farmers in the Gorge. We collected data on fish composition, abundance and gear used from four sampling stations. 34 fish species belonging to 13 families were present in the Gorge. Our findings revealed that Bagridae (25.1%), Cichlidae (37.1%) and Mormyridae (14.5%) were most abundant families contributing 76.7% by number and 75% by weight of the total catch followed by Characidae (9.6%), Cyprinidae (7%) and Centropomidae (3%) constituting (19.6%) by number and 8.7% by weight. Schilbeidae (1.1%) Clarridae (0.8%), Hepsetidae (0.7%0, Mochokidae (0.6%), Channidae (0.5%), Icthyoboridae (0.2%) and Malapteruridae (0.1%) were least represented. We found that commonly used gears were cast net, traps, bamboo stems, spears, gura net and gillnet was the major fishing gears in used. Also, the gillnet fisheries showed the sensitivity of experimental gillnets mesh sizes to different fish species. 78.4 mm, 112 mm, 67.2 mm mesh sizes were efficient in catching Chrysichthys nigrodigitatus, Lates niloticus and the cichlids respectively. The study contributed to baseline data on the fish composition, distribution and gear selectivity on fish catch; thus, aiding fisheries policy makers in the management of this water body.
Biography:
Dipak Pandey has completed his Master’s degree in Chemistry Education from Tribhuvan University, Nepal and Master’s degree in Agriculture with major ‘Bio-resource production sciences’ specialized in Fisheries Research under supervision of Professor Takahiro Matsubara from Ehime University, Japan. Currently, he is pursuing his Doctoral degree at United Graduate School of Agricultural Sciences (UGAS), Ehime University, Japan.
Abstract:
Japanese anchovy (Engraulis japonica) is a very important marine species for commercial fisheries in addition to marine ecosystem. They are multiple spawning type species having oval-shaped pelagic eggs. However, little has been known about physiological and biochemical features on the process of their egg production. The aim of this study is to clarify morphological and biochemical changes of oocytes during final oocyte maturation (FOM), especially focused on proteolytic degradation of vitellogenin (Vg)-derived yolk proteins (YPs). The oocytes/eggs were collected from 1 pm to 10 pm coincide with the times of FOM and spawning in captive condition. Morphological observations showed that FOM was completed within 8 hours, and the processes were classified into five stages, including post-vitellogenic oocyte stage (St-I) to ovulated egg stage (St-V). Wet mass of oocytes increased from 69 µg (St-I) to 244 µg (St-V) due to high increases of water contents suggesting drastic hydration occurred during the FOM. Three types of Vgs were identified in the liver of Japanese anchovy, including Ja-VgAa, -VgAb and -VgC, and quantitative analysis of Ja-Vgs mRNA expression levels indicated that VgAa and VgAb were probably majors having important roles on yolk accumulation. The analyses of gel chromatography coupled with SDS-PAGE demonstrated proteolytic degradations of major YPs during the latter half of FOM. On the other hand, free amino acid (FAA) contents increased approximately 11 folds high during FOM. These results suggest that FAAs yielded from the proteolysis of YPs generate buoyancy of eggs involved with drastic hydration.
Sandip Bhatta
Nepal Agriculture Research Council, Nepal
Title: The endocrine function of germ cells directly regulate body composition in fish
Biography:
Sandip Bhatta has completed his Master’s degree and PhD in Agriculture Sciences from United Graduate School of Agriculture Sciences (UGAS), Ehime University, Japan with major ‘Bio-resource production sciences” specialized in Fisheries Research under supervision of honorable Professor Takeshi Miura. Currently, he is joining a Fisheries Research Program at Nepal Agriculture Research Council.
Abstract:
This study evaluates the interactions between body composition and reproduction between male and female tilapia ((Oreochromis mossambicus). Reproductive organs are known to be important organs for somatic growth, but direct evidence for their role is not available elsewhere. Here, using a fish model, we report direct evidence that gonads are endocrine organs equal to the pituitary in controlling body growth. Gonadal loss of function, gain of function and rescue of growth were investigated. Gonadectomy significantly retarded body composition; however, this retardation was rescued by the implantation of extirpated gonads in the body cavity. GH is classically associated with pituitary and IGF-1 is the liver. This study clearly exhibit that both hormones are expressed as mRNA and protein in the testis and ovary. GH was expressed in the sertoli cells of testis and in the granulose and fibroblast (thecal) cells of ovary. Real time-PCR and enzyme linked immunosorbent assays (ELISA) were used to measure changes in the rate of synthesis growth hormone (GH), insulin like growth factor-1 (IGF-1) and sex steroids in sham operation, gonadectomy and ectopic transplanted fish. After the 50 days post-surgery, gonadectomized fish had significant lower body weight then sham-operated fish. The gonadectomized fish did not exhibit advancement of spermatogenesis and oogenesis; thus prevention of sexual maturation by gonad removal was accompanied by retarded body growth. Measurement of sex steroid hormones 11-ketotestosterone (11-KT) in males and es-tradiol-17β (E2) in females decreased significantly in gonadectomized fish and concentrations in fish with ectopically transplanted gonads recovered to the same level as those in sham operated fish. Gonadal GH, sex steroids and advancement of spermatogenesis and oogenesis at the auto-transplanted site suggests that in addition to pituitary, gonads are major participants in the regulation body growth in tilapia.
Ha Thi Thu Bui
Curtin University, Australia
Title: Technical feasibility of cultivating Sargassum podacanthum and Sargassum linearifolium in inland saline water in Western Australia
Biography:
Ha Thi Thu Bui is pursuing her PhD in Aquaculture at Curtin University, Australia. She has been a Researcher at Research Institute for Aquaculture in Vietnam since 1998, after graduating in Aquaculture Engineering with excellent grades, working on socio-economic studies in Fisheries sector. She completed her Master of Aquaculture at Nha Trang Fisheries University in Vietnam in 2001 with first class-excellent grade. She completed her Master of Natural Resource Management from University of Western Australia in 2011. She has been pursuing her PhD since 2012 sponsored by Vietnamese Government and Curtin International Post-graduate Research Scholarship. Topic of her PhD research is on “Growing seaweed species in inland saline waters in Western Australia”.
Abstract:
Aquaculture using salt-affected land is considered as an additional resource for mariculture in Australia, India and USA. However, the deficiency of potassium in ISW is the major constraint in cultivating marine aquatic species. The aim of this research was to investigate the technical feasibility of cultivating Sargassum spp. in inland saline water (ISW) in Western Australia by conducting a three-phased research. The first phase was aimed to determine the suitable seaweed species which can survive in ISW. Sargassum linearifolium and S. podacanthum were selected out of seven trialled species. The second phase focused on investigating the optimum potassium concentration to grow Sargassum spp. in ISW by testing the different levels of potassium fortification in ISW (33%, 66% and 100% of potassium concentration equivalent to potassium concentration in ocean water) under both indoor and outdoor conditions. The results showed that 100% fortification of potassium by potassium chloride or sulphate of potash can sustain the growth of Sargassum spp. in ISW. The relationship between the fresh biomass of S. linearifolium and cultivation time was correlated (R2>0.7) in all potassium fortified ISW. The third phase attempted to improve the productivity of both Sargassum spp. by enriching nutrients to 100% potassium-fortified ISW. Only S. podacanthum showed the highest dry biomass at a nutrient mix of 160 mg l-1 of ammonium and 16 mg l-1 phosphate in potassium-fortified ISW. After 84 days of cultivation, the biomass of both species was significantly (P<0.05) affected by the nutrient levels. It is technically feasible to cultivate S. linearifolium and S. podacanthum in 100% potassium-fortified ISW.
Bingyuan Yang
Chinese Academy of Sciences, China
Title: Repeated handling compromises the immune suppression and improves the disease resistance in overwintering channel catfish (Ictalurus punctatus)
Biography:
Bingyuan Yang is pursuing his Doctorate degree at Institute of Hydrobiology, Chinese Academy of Sciences. He is working on Fisheries and Fish Nutrition. He has published three papers in reputed journals and won the national scholarship of CSC in 2015.
Abstract:
In winter, fish have suppressed immune functions and are susceptible to bacteria or virus which may lead to a high mortality. It is necessary to improve the immune response and disease resistance for overwintering fish. The present study tested the hypothesis that appropriate repeated handling could compromise the immune depression and increase the disease resistance in channel catfish over winter. Before the experiment, 35 fish randomly assigned to one of six cages. Three cages were designed as the control group and did not receive any interfere. Fish in the other three cages received a weekly repeated handling of an air exposure for 5 minutes. Fish were not fed over winter. At the end of the trial, fish were challenged with Aeromonas hydrophila. Plasma cortisol levels in the control fish were induced at 6 h post challenge and then declined to the normal levels. However, plasma cortisol levels in the repeated handled fish did not show any significant change after bacteria challenge. The reduced inducement of HSP70 expression by repeated handling was observed in fish post bacterial challenge. After overwintering, repeated handled fish exhibited increased CAT activities and reduced MDA contents. TAOC, CAT and SOD activities of channel catfish were enhanced by repeated handling post bacterial challenge. The enhanced up-regulation of IL8, IL1β-a, IL1β-b together with the immune related genes of TLR2, TLR3, NOD1and NOD2 by repeated handling was found in catfish after bacterial challenge.
Biography:
Kiran Bhatta has completed his Master’s and PhD from United Graduate School of Agricultural Sciences (UGAS), Ehime University, Japan with major in Bio-resource Production Sciences specialized in fisheries conservation and management since 2006 -2012 AD. Currently he works for World Vision Advocacy Forum (WVAF) at the National NGO of Nepal. His current research and working area is primarily involved in fisheries conservation and management. This program is designed to provide training in ecological principles, field research techniques, and the application of these tools for the management and conservation of fisheries resources. The program responds to the research needs of the fisheries pocket area of Nepal and research based organizations.
Abstract:
In teleost fishes, growth hormone (GH) and sex steroids appears to play an important regulatory role in several physiological events, including reproduction, growth and development. GH secretion is regulated by hypothalamic neuroendocrine factors that either act directly on the somatotrophic cells in the pituitary gland, or modulate the secretion or activity of other neuroendocrine factors. In addition, the degree of the neuroendocrine influence on GH release is influenced by the nutritional and reproductive state of the fish. Thus, the neuroendocrine control of GH secretion in fishes is complex, and still poorly understood. In this study, we clearly state that sex steroids 11-ketotestosterone (11-KT) levels peaked during the transition from spermatogenesis to spermiogenesis at 90 daf, and estradiol-17b (E2) levels increased during transition from the previtellogenic to mature vitellogenic stages at 75 daf. The maturation inducing hormone 17a-20b-dihydroxy-4-pregnen-3-one (DHP) involved final gametes maturation increased during reproductive maturation in both male and female. A consistent positive relationship between body growth, gonadal GH, sex steroids and advancement of spermatogenesis and oogenesis clearly indicate that these factors are essential in the reproductive endocrine axis to stimulate overall body growth regulation of developing juvenile fish.
Sirirat Chatvijitkul
Auburn University, USA
Title: Pollution potential indicators for feed-based fish and shrimp culture
Biography:
Sirirat Chatvijitkul has completed her PhD and MS from School of Fisheries, Aquaculture, and Aquatic Sciences, Auburn University. Her expertise is in “Nutrition in aquatic species”. She has conducted research focused on “Alternative protein sources in feeds, exogenous enzymes improving digestibility and nutrient retention in aquatic animals, sustainability and environmental issue in feed-based aquaculture”. She is currently working at Auburn Research Station in Gulf Shores, AL. She is responsible for developing feed formulations, producing experimental feeds, conducting experiments in RAS systems, culturing white shrimp in small-scale farming.
Abstract:
Biochemical oxygen demand, acidification potential and elemental waste loads from feed were determined for production of channel catfish Ictalurus punctatus, tilapia Oreochromis spp. Atlantic salmon Salmo salar, rainbow trout Oncorhynchus mykiss, and white leg shrimp Litopenaeus vannamei. Loads of these variables in culture systems (system loads) at typical FCRs ranged from 1090-1500 kg t-1 for biochemical oxygen demand, 270-440 kg t-1 for acidification potential, 1186-1885 kg t-1 for carbon dioxide, 35.9-63.5 kg t-1 for nitrogen, and 6.1-15.9 kg t-1 for phosphorus. Using these estimates as representative of feed-based aquaculture and literature data on the proportions of system waste loads typically discharged to the environment (environmental loads), the approximate amounts of waste generated globally by feed-based aquaculture were estimated small in comparison to approximate estimates of global anthropogenic waste. Nevertheless, aquaculture should lessen its environmental waste load and reducing waste load by improving FCR will be discussed.
Mumdoh Elhassan Abdalla Elhassan
University of Khartoum, Sudan
Title: Assessment of biological treatment of Red Sea water contaminated by organic phosphate using Aquatic Seashells
Biography:
Mumdoh Elhassan Abdalla Elhassan has completed his MSc at Gezira University. Currently, he is pursuing his PhD at Institute of Endemic Disease, University of Khartoum.
Abstract:
The most dangerous threaten to marine environment is the sea water contamination. This study assessed the biological treatment of contamination in Dongonab in red sea using aquatic seashells. In this study, the seashells were bred (pearl oyster) and kept in a closed basin in a managed natural reserve for a period of six months. The concentration of chemical contaminants (organic phosphates) in water was measured, and seashells samples were collected from the area (before and after the experiment). 60 samples of sea water were collected from the farm from the depth of the 220 cm because they may contain the largest amount of pollutants. Chemical measurements were conducted in a laboratory in the reserve. This study is done to assess the capabilities of seashells for the filtration of these chemical contaminates, The study found a decrease in phosphate concentration from an average of (32.95 mg/L) to (1.75 mg/L) and within a period of 36 hours from the filtration and an increase in ammonium concentration from an average of 4.51 mg/L in the contaminated water to an average of 20.87 mg/L, and therefore, a significant increase of planktons (the basic material of the biodiversity). The study concluded that marine seashells farms can contribute naturally and effectively in reducing the spread of chemical contaminants (especially organic phosphate) and thus, can contribute to increase the biodiversity. This research recommends studying the bioremediation and natural treatment of chemical pollution by using the seashells in open sea or in the farm of the seashells.
Olorunfemi Momodu F
Rhodes University, South Africa
Title: Detection of Aspergillus Section Flavi and aflatoxins in locally formulated fish feeds from South-Western Nigeria
Biography:
Olorunfemi Momodu F is pursuing her PhD at University of Ibadan in Nigeria. Her research interests includes “The study of moulds, mycotoxins research, foods and feeds safety and finding methods for extending shelf life of agricultural produce”. She is an awardee of Organization for Women in Science for the Developing World (OWSD) in Italy and has published nine papers on subjects in her research field. Currently, she is on a research visit to Chemistry Department of Rhodes University, South Africa where she is developing tools to help in ameliorating multi-mycotoxins in fish feeds.
Abstract:
Aspergillus section flavi (ASF) is a group of molds associated with aflatoxin production. They are responsible for aflatoxicoses in humans and animals through the feed-animal-food-human chain. Aflatoxins are potent carcinogenic secondary metabolites produced by the Aspergillus spp. Their presence in fish feeds reduce feed quality and feeding inefficiencies leading to low productivity, poor growth and untimely deaths. Detection of ASF and aflatoxins were carried out on 94 randomly collected fish feed samples from different fish farms in South-Western Nigeria. ASF were detected in all samples with 1873 ASF isolated. Aspergillus flavus, Aspergillus parasiticus, unnamed taxon and Aspergillus tamari isolated was 1806 (96.40%), 12 (0.64%), 3 (0.16%) and 52 (2.78%) respectively. Aflatoxin B1 was detected in 92% of samples followed by aflatoxin G1 (85%), aflatoxin B2 (81%), aflatoxin M1 (75%) and aflatoxin G2 (36%). Highest aflatoxin concentration was 550.8 µg/kg for aflatoxin B1 while highest total aflatoxin concentration recorded was 826.9761 µg/kg. Percentage of samples having total aflatoxin concentration higher than the Maximum Allowable Limit (MAL) in animal feeds as recommended by USFDA (20 µg/kg) was 79.79%. Considering the high incidence of ASF and aflatoxin contamination of sampled fish feeds, the fish industries in South-western Nigeria may be at risk of economic losses due to aflatoxicoses in the fish species.
- Aquaculture Industry: Strategic Framework | Marketing & Pricing of Fish | Regulating Fisheries | Entrepreneurs Investment Meet
Chair
Xinzhong Wu
Qinzhou University, China
Co-Chair
Seher Dirican
Cumhuriyat University, Turkey
Session Introduction
Habte-Michael Habte-Tsion
Nanjing Agricultural University, China
Title: Threonine affects growth, digestion capacity and immunity of fish
Biography:
Habte-Michael Habte-Tsion has completed his BSc in Marine Biology & Fisheries at University of Asmara, Eritrea. From 2002-2011, he was working at different aquaculture activities including Seawater Farms Eritrea and he was part of an advanced aquaculture programs. From 2011-2016, he studied MSc and PhD at Nanjing Agricultural University. During his MSc and PhD studies, he was engaged in research of Fish Nutrition, especially the requirements and further molecular mechanisms that prove the metabolic and immune functions of protein-essential amino acids. He has published one academic book and 24 original articles in preeminent peer-reviewed scientific journals.
Abstract:
Blunt snout bream (Megalobrama amblycephala) is a major cultured freshwater fish with great consumer demand and high production in China (e.g. about 0.70 million tons in 2012). However, few nutritional studies have been reported about this species. Indeed, this study conducted a nine week feeding trial to investigate the effects of threonine (Thr) on the growth, digestion capacity and immunity of juvenile blunt snout bream. For this purpose, juvenile fish (in triplicates) were fed with five diets containing graded Thr levels (0.58, 1.08, 1.58, 2.08 or 2.58% of the diet) to apparent satiation four times daily. At the end of the feeding trial the growth of fish and development of digestive organs, activities of digestive, absorptive and antioxidant enzymes and immune responses elevated as dietary Thr levels increased up to 1.58% (P<0.05), and thereafter decreased in most cases. The relative gene expression levels of enzymes (digestive chymotrypsin, trypsin, amylase and lipase), brush-border (AKP, Na+/K+-ATPase and γ-GT) and antioxidant (Cu/Zn-SOD, Mn-SOD, CAT, GPx1 and GST), target of rapamycin (TOR) and insulin-like growth factor-I (IGF-I) were up-regulated and the highest values were observed with 1.58% Thr or 1.58 and 2.08% Thr, whereas the gene expression of eukaryotic translation initiation factor 4E-binding protein (4E-BP2) and tumor necrosis factor alpha (TNF-α) were down-regulated as Thr levels increased up to 1.58% and thereafter increased (P<0.05). The dietary Thr requirement for juvenile blunt snout bream was estimated to be 1.57% of the diet, corresponding to 4.62% of dietary protein. The overall results indicate that the optimum Thr level improved growth performance, digestion and antioxidant capacity and immune status of juvenile blunt snout bream. This study could provide an insight in studies of fish nutrition and shed light on specific molecular mechanisms, which is fundamental in developing complete commercial feed for sustainable aquaculture of cultured fish.
Farzaneh Farokhi
Islamic Azad University of Sari, Iran
Title: The single-cell gel electrophoresis assay to determine apoptosis induced by blood cells in Rutilus rutilus caspicus
Biography:
Farzaneh Farokhi has completed her PhD from Science and Research Branch, Islamic Azad University, Tehran, Iran. She completed her Graduation in Marine Biology in 2013. Currently, she is an Assistant Professor at Azad University of Sari, Iran. She has published more than 10 papers in reputed journals.
Abstract:
The present study aimed to determine the biomarkers of malathion in Rutilus rutilus caspicus by studying genotoxicity and ecophysiologic reactions. To achieve this goal, the lethal concentration (Lc50) of malathion in Rutilus rutilus caspicus was examined. The effect of different 0.1%, 0.05% and 0.01% ppm concentrations on DNA of red blood cells of this species was observed, following the sampling which was done in the 3rd, 13th and 23th days of malathion exposure and 30 days after the exposure. Although the study did not show any significant deviation regarding the number of apoptotic cells in some types of exposed specimens to malathion (P>0.05), a significant difference was observed between the control group and the treatments in all days of sampling (P<0.05). It has also been indicated that Rutilus rutilus caspicus were sensitive to malathion and the induced apoptosis was dose dependent and increased by extending the periods of exposure.
Sidi Imad Cherkaoui
Moulay Ismail University, Morocco
Title: Native freshwater fishes of Morocco: current knowledge, threats analysis and conservation perspectives
Biography:
Sidi Imad Cherkaoui has completed his PhD from Mohamed V University and Post-doctoral studies from Natural History Museum of Paris (France) and Faculty of Sciences of Gabes in Tunisia. He is currently an Associate Professor in Ecology and Wildlife Management at Moulay Ismail University (Meknes, Morocco) and Visiting Lecturer of International University of Casablanca. He has published more than 22 papers in reputed journals and has been serving as commission member of IUCN SSC and CMS. He has attended several conferences in more than 30 countries.
Abstract:
Little is known about native freshwater fish diversity in Morocco, especially after the broad national program of introduction of exotic species applied for over 90 years. This paper is an attempt to describe the current situation emphasizing the distribution of the various species, their current status using detailed threats analysis and propose conservation measures. The freshwater fish fauna of Morocco is the richest of the Maghreb region and is composed of 65 species belonging to 14 families. 36 species are indiginious, of which, 19 are endemics including six newly described Taxa. We recognise pronounced species richness and a high degree of endemism of the Moroccan ichthyofauna (52.78%). Using IUCN categories, one species is globally extinct (EX), four species are vulnerable (VU), two are endangered (EN) and two are critically endangered (CR). 27 species were introduced mainly for aquaculture and sport fishing, of which, four never became established and 23 were established. Two species were listed as invasive. As a result of climate change impact, agricultural and industrial development as well as non native species introduction, the populations of native fishes have become highly threatened in Morocco. Long-term monitoring and researches are therefore strongly needed in order to implement appropriate conservation measures.
Sogbesan Olukayode Amos
Modibbo Adama University of Technology, Nigeria
Title: Performances of Orechromis niloticus (Linn.) fed moringa leaf meal supplemented diets
Biography:
Sogbesan Olukayode Amos has completed his PhD from University of Ibadan, Nigeria and Post-doctoral studies from Central Institute of freshwater Aquaculture, Kausalyaganga, Bhubaneswar Orissa, India. He is a Senior Lecturer and immediate past Head of Department of Fisheries, Modibbo Adama University of Technology, Yola. He has more than 50 peer reviewed journals to his credit and he is an Editorial Board Member of reputed journals.
Abstract:
Utilization of moringa (M. oleifera) as soybean supplement in the diet of Nile tilapia (Oreochromis niloticus) was carried out for 12 weeks. Moringa leaf was purchased from market along with other feed ingredients. Moringa was processed by drying under shade for one week followed by blanching at a temperature of between 60oC-80oC for 15 minutes to minimize or deactivate the anti-nutritive. Moringa leaf was used at inclusion level of 0% (diet one-control), 10% (diet two), 20% (diet three), 30% (diet four) and 40% to replace soybean meal. Oreochromis niloticus were stocked equally in ten experimental tanks of 50 L in a semi-flow through system and each treatment was in triplicates. Weekly weights, lengths and feed intake were recorded. Fish were also subjected to proximate analysis. The results of mean weight gain shows that diet one (control) recorded the highest weight followed by diet three (20%) and diet four (30%) has the lowest mean weight gain. The fish fed diet three which contain 20% inclusion levels of PMLM has the highest FCR followed by 0%, 10% and 40% inclusion of PMLM. The fish fed with diet three (20%) has the highest SGR while the lowest is recorded in the diet five (40%) inclusion of PMLM. PER followed the same pattern. Based on the cost of feed production, diet four which contain (30%) inclusion levels of PMLM is the cheapest but the economic evaluation of the experimental diet shows diet three (20%) having highest benefit cost ratio followed by diet two (10%). Hence, the results from this study on growth performance and benefit cost ratio shows that 20% partial replacement of soybean meal is applicable and recommended for practical diet of Oreochromis niloticus in achieving a sustainable aquaculture.
Berchie Asiedu
University of Energy and Natural Resources, Ghana
Title: Aquaculture in troubled climate: Farmers’ perception of climate change and their adaptation strategies in Ghana, West Africa
Biography:
Berchie Asiedu has completed his PhD from University of Ghana and Post-doctoral studies from University of Ibadan, Nigeria. He is a Lecturer and Researcher in Department of Fisheries & Water Resources, University of Energy and Natural Resources, Ghana. He has published more than 150 papers in reputed journals and has been serving as an Editorial Board Member of repute.
Abstract:
Aquaculture is one of the fastest growing industries within the fisheries sector of Ghana, serving as a source of protein, food security, employment, economic growth, and poverty reduction strategy for majority of Ghanaians. Climate change due to low rainfall and high temperatures remains the most serious threat to sustainable aquaculture development in Ghana. The aim of this study was to assess the awareness level and perception as well as adaptation strategies adopted by small scale aquafarmers on climate change. Climatological data, namely, temperature, rainfall and relative humidity were collected for the period 1985-2015 from the Ghana meteorological agency and analysed to determine the trends. The study adopted stratification and simple random sampling technique in obtaining 40 respondents (aquafarmers and other stakeholders) from the sunyani aquaculture zone of Ghana through questionnaires administration. The analysis of the data utilised descriptive statistics. Findings of this study indicate that there have been significant changes in temperature and rainfall pattern. Aquafarmers have considerable knowledge on climate change from sources such as radio, television and schools. A number of adaptation strategies are employed by aquafarmers to deal with climate change, including, water management, construction of bore-holes, sitting farms close to water bodies, adjusting fish stocking time and creation of embankment to avoid floods. Extension education should be carried out to enhance aquafarmers adaptation responses to the negative impacts of climate change which is a threat to aquaculture production and sustainable livelihood.
Avinash Talukdar
Central Institution of Fisheries Education, India
Title: Effect of dietary carbohydrate on the gene expression of Myod and Myf5 in clarias batrachus (Linnaeus, 1758)
Biography:
Avinash Talukdar has completed his Master’s degree from ICAR-CIFE, Mumbai having specialization in Fish Nutrition and Feed Technology. Currently, he is pursuing his PhD in the same specialization.
Abstract:
The nutritional regulation of skeletal muscle growth is very little documented in fish. It requires understanding of how dietary components are processed and trigger molecular, tissue and whole body response. A feeding trial of 60 days was conducted to study the growth trajectory, body composition, enzyme activities and expression of MyoD and Myf5 genes in Clarias batrachus (Asian catfish) fingerlings fed with graded level of carbohydrate. 145 fishes were randomly distributed into four experimental groups in triplicates. Four iso-nitrogenous and iso-lipidic diets of 15%, 25%, 35% and 45% gelatinized carbohydrate designated as T1, T2, T3 and T4 respectively were prepared. White muscle samples were collected for every 15 days interval to study the expression of MyoD and Myf5 genes. At the end of the experiment, fishes were sampled to study the growth parameters and enzyme activities. The growth parameters, such as weight gain, SGR, FCR and PER were not affected by dietary level of carbohydrate among T2, T3 and T4 treatment groups but significantly lower (P<0.05) value was found to be in T1 group. Body composition differed among the treatments. Body lipid of T4 group was found to be significantly higher (P<0.05) than the other treatments groups. Metabolic enzymes such as AST, ALT and hexokinase activity were not affected by dietary carbohydrate and found to be similar among the groups. G6PDH and amylase exhibit significantly (P<0.05) higher activity in T3 and T4 group. The partial MyoD and Myf5 gene were cloned and sequenced for the first time in Clarias batrachus (Linnaeus 1758) and their temporal expression was monitored in different intervals (15th, 30th, 45th and 60th day) in the experimental groups. Significantly higher (P<0.05) mRNA expression of MyoD and Myf5 gene was observed in T3 group (35% GC). MyoD and Myf5 genes were upregulated on 60th day and 45th day respectively, during the feeding trial. Hence, overall result indicates that 35% carbohydrate can improve growth and promote myogenesis but higher carbohydrate will favor adipogenesis in Clarias batrachus. In addition, the study also reveals that Myf5 shows more immediate response than MyoD to dietary carbohydrate. These studies demonstrate that carbohydrate can be a potent regulator of muscle development and growth and provide new opportunities in nutri-genomic studies.
Reuben Jiya Kolo
Federal University of Technology, Minna, Nigeria
Title: Comparative studies on morphological characteristics and filleting yield of Clarotes laticeps and Clarias gariepinus
Biography:
Reuben Jiya Kolo has completed his PhD in 1996. He is currently the Dean of School of Agriculture and Agricultural Technology, Federal University of Technology, Minna, Nigeria. He is a member of the academic staff in Department of Water Resources, Aquaculture and Fisheries Technology of the same institution. He has supervised and graduated several PhD and Master of Technology students. He is a Consultant to Federal Government of Nigeria on Environmental Impact Assessment of proposed projects. He has published over 50 journal articles in referred journals, five book chapters and attended several international and national conferences and workshops.
Abstract:
The morphological characteristics and fillet yield of Clarotes laticeps and Clarias gariepinus were investigated. 30 fresh samples each of Clarotes laticeps and Clarias gariepinus collected from Wadata market, Makurdi, Benue state, Nigeria were used for this research work. All the morphological characteristics measured (total length, body weight, head length, head width, head weight, gut length, gut weight and total hard parts weight) were significantly higher (p<0.05) for Clarotes laticeps than Clarias gariepinus except the mean standard length which was higher in Clarias gariepinus (27.73+ 4.26 cm) than in Clarotes laticeps (24.81+ 0.98 cm). The percentage fillet yield was significantly higher in Clarotes laticeps (48%) than in Clarias gariepinus (46%). However, the percentage non-edible part was higher than the percentage edible part (fillet) in both Clarotes laticeps (52% and 48% respectively) and Clarias gariepinus (54% and 46% respectively). The result reveals that the bulk of the body of both Clarotes laticeps and Clarias gariepinus is made up of non-edible parts, however, the most economical for consumers would be Clarotes laticeps as it gave more fillet yield per unit weight.