Search results for: fish biology
902 Triploid Rainbow Trout (Oncorhynchus mykiss) for Better Aquaculture and Ecological Risk Management
Authors: N. N. Pandey, Raghvendra Singh, Biju S. Kamlam, Bipin K. Vishwakarma, Preetam Kala
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The rainbow trout (Oncorhynchus mykiss) is an exotic salmonid fish, well known for its fast growth, tremendous ability to thrive in diverse conditions, delicious flesh and hard fighting nature in Europe and other countries. Rainbow trout farming has a great potential for its contribution to the mainstream economy of Himalayan states in India and other temperate countries. These characteristics establish them as one of the most widely introduced and cultured fish across the globe, and its farming is also prominent in the cold water regions of India. Nevertheless, genetic fatigue, slow growth, early maturity, and low productivity are limiting the expansion of trout production. Moreover, farms adjacent to natural streams or other water sources are subject to escape of domesticated rainbow trout into the wild, which is a serious environmental concern as the escaped fish is subject to contaminate and disrupt the receiving ecosystem. A decline in production traits due to early maturity prolongs the culture duration and affects the profit margin of rainbow trout farms in India. A viable strategy that could overcome these farming constraints in large scale operation is the production of triploid fish that are sterile and more heterozygous. For better triploidy induction rate (TR), heat shock at 28°C for 10 minutes and pressure shock 9500 psi pressure for 5 minutes is applied to green eggs with 90-100% of triploidy success and 72-80% survival upto swim-up fry stage. There is 20% better growth in aquaculture with triploids rainbow trout over diploids. As compared to wild diploid fish, larger sized and fitter triploid rainbow trout in natural waters attract to trout anglers, and support the development of recreational fisheries by state fisheries departments without the risk of contaminating existing gene pools and disrupting local fish diversity. Overall, enhancement of productivity in rainbow trout farms and trout production in coldwater regions, development of lucrative trout angling and better ecological management is feasible with triploid rainbow trout.Keywords: rainbow trout, triploids fish, heat shock, pressure shock, trout angling
Procedia PDF Downloads 120901 Substitution of Fish Meal by Local Vegetable Raw Materials in the Feed of Juvenile Nile Tilapia (Oreochromis Niloticus, Linne, 1758) in Senegal
Authors: Mamadou Sileye Niang
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The study is a contribution to the development of a feed for juvenile tilapia Oreochromis niloticus, from local raw materials in order to reduce the cost of feeding farmed tilapia in Senegal. Three feeds were formulated from local raw materials. The basic composition of the tested feeds is as follows: A1 (peanut meal, rice bran, millet bran, maize meal and no fish meal); A2 (peanut meal, rice bran, millet bran, maize meal and 10% fish meal) and A3 (peanut meal, rice bran, millet bran, maize meal and 25% fish meal). All feeds contain 31% protein. The trial compared three batches, in 2 replicates, with different diets. The initial weight of the juveniles was 0.37± 0.5g. The daily ration was distributed at 9 am and 4 pm. After 90 days of the experiment, the final mean weights were 2.45 ± 0.5g; 2.75±0.5g; and 4.67 ± 0.5g for A1, A2, and A3, respectively. A performance test, of which the objective was to compare growth parameters, was conducted. The results of the growth parameters of juveniles fed A3 were significantly higher (p < 0.05) than those fed A1 and A2. The weight growth study shows similar growth during the first month. However, from this date onwards, juveniles fed A3 show a faster growth, which is maintained throughout the experiment. On the other hand, the Protein Efficiency Coefficient and the Survival Rate showed no significant difference. The zootechnical parameters are not significantly different (p > 0.05) between the two tanks for the same feed treatment.Keywords: nutrition, feed, fingerlings, Oreochromis, local raw materials, feed cost
Procedia PDF Downloads 63900 Effect of Ginger (Zingiber Officinale) And Garlic (Allium Sativum) Mixture on Growth Performance, Feed Utilization and Survival of Clarias Gariepinus Fingerlings
Authors: Maryam I. Abdullahi, Suleiman Aliyu, Armaya'u Hamisu Bichi
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The study was conducted at the University Fish Farm, Federal University Dutsinma. The aim of the study was to determine the effects of dietary supplementation of Allium sativum and Zingiber officinale mixture on growth performance, feed utilization and survival of C. gariepinus fingerling reared in tank system. The experimental setup comprised of four treatment (4) groups labeled as T1, T2, T3 and T4, each treatment replicated 3 times with ten (10) fingerlings in each replicate respectively. Treatment 1 contained 0.5% of Zingiber officinale and 0.5% of Allium sativum (ZO-AS: 1.0%), Treatment 2 contained 0.75% Zingiber officinale, and 0.75% garlic (ZO-AS: 1.5%) while T3 contained 1% ginger and 1% Allium sativum (ZO-AS: 2.0%) respectively. The experiment lasted for twelve (12) weeks (84 days). The survival rate ranges from 90% - 100%. With a higher Final Mean Weight (893.10) and Percentage Mean Weight (942.65) as compared to the control group and others. There was no significant difference (p > 0.05) in the FMW (893.10) of the fish fed 1.5g/kg of Garlic and Ginger diets than the control (687.00). The SGR (1.20) of fish-fed Zingiber officinale and Allium sativum fortified diets shows that there is no significant difference between treatments fed 1.5g/kg Zingiber officinale and Allium sativum and the control group. Generally, there was an increased survival rate in the experimental fish-fed Zingiber officinale and Allium sativum-supplemented diets as compared to the control.Keywords: clarias gariepinus, zingiber officinale, allium sativum, fingerlings
Procedia PDF Downloads 60899 Effect of Different Commercial Diets and Temperature on the Growth Performance, Feed Intake and Feed Conversion Ratio of Sobaity Seabream Sparidentex hasta
Authors: Seemab Zehra, A. H. W. Mohammed, E. Pantanella, J. L. Q. Laranja, P. H. De Mello, R. Saleh, A. A. Siddik, A. Al Shaikhi, A. M. Al-Suwailem
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Two separate feeding trials were conducted to determine the effects of using different commercial diets and water temperatures on the growth performance, feed intake, feed conversion ratio (FCR) and condition factor of sobaity seabream Sparidentex hasta. In experiment I, growth performance, feed intake, protein efficiency ratio (PER), feed conversion ratio (FCR) and survival (%) of sobaity seabream Sparidentex hasta (330.5±2.6 g; 26.9±1.0 cm) were evaluated by four different commercial diets (1, 2, 3 and 4) for 80 days. The daily weight gain was around 3.2 g day-1 with an SGR of 0.7% day-1. Both the FCR and PER in the fish were significantly better in diet 2 that contained 46.36% crude protein and 12.54% crude fat. In experiment II, (99±2.6 g; 17.1±1.0 cm). The fish were cultured in 1m3 tanks supplied with seawater from the Red Sea wherein three different rearing temperatures were set as treatments (24, 28 and 32°C). Fish were fed with a commercial diet based on the results of experiment I (46.4% protein; 20.1 MJ kg-1 energy) to satiation for 96 days. Total weight gain was significantly higher for the fish reared in the 32°C group (158.57 g) followed by the 28°C group (138.25 g), while the lowest weight gain was observed in the 24°C group (116.98 g). The FCR was significantly lower in the 32°C group (1.62) as compared to 28 (1.8) and 24°C (1.85) groups. Based on the results obtained from these preliminary studies (experiment I and II), sobaity seabream can attain better growth performance, FCR and PER at 32°C in the Red Sea by feeding commercial diet 2.Keywords: Sparidentex hasta, nutrition, FCR, Red Sea, growth performance
Procedia PDF Downloads 73898 Nutritive Advantage of Mealworm (Tenebrio molitor) in the Diet of White Shrimp (Litopenaeus vannamei)
Authors: Tae-ho Chung, Chul Park, Gi-wook Shin, Joo-min Kim, Seong-hyun Kim, Namjung Kim
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Mealworm (Tenebrio molitor) was evaluated to investigate the effect of partial or total replacement of fish meal in diets for white shrimp, Litopenaeus vannamei. Experimental groups of shrimp with average initial body weight (2.43 ± 0.54 g) were fed each with 4 isonitrogeneous (38% crude protein) diets formulated to include 0, 25, 50 and 100% (diets 1 to 4, respectively) of fish meal substituted with mealworm. After eight weeks of feeding trials, shrimp fed with diet 3 and 4 revealed the highest values for live weight gain(8.01 ± 2.51 and 7.93 ± 1.12), specific growth rates (2.70 ± 1.12 and 2.59 ± 0.51) as well as better feed conversion ratio (2.69 ± 0.09 and 2.72 ± 0.19) compared to the control group with statistically significant manner (p<0.05). Survival range was 98% in all the treatments. An increase in weight gain and other growth associated parameters was observed with higher replacement. These results clearly indicate that 50% and 100% of fish meal protein in shrimp diet can be replaced by mealworm not only without any adverse effect but also the effect of promoting growth performance.Keywords: mealworm, Litopenaeus vannamei, Tenebrio molitor, white shrimp
Procedia PDF Downloads 463897 Environmental Drivers of Ichthyofauna Species Diversity and Richness in the Lower Reaches of Warri River, a Typical Mangrove Ecosystem in the Niger Delta, Nigeria
Authors: F. O. Arimoro, F. N. Okonkwo, R. B. Ikomi
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The environmental determinants structuring species richness has been generating interest recently but we still lack an understanding of these patterns in various regions (e.g. Afrotropical), and how seasons help to structure these patterns. Our aim was to assessed the environmental drivers importance in regulating species richness and community structure of fish species. The lchthyofauna assemblage of Warri River, Niger Delta area of Nigeria was studied between August 2013 and July 2014. A total of 1152 individuals representing 43 species in 23 families and 30 genera were caught. Of the 43 species recorded, 67.4%, 53.5% and 67.4% of the species occurred in Stations 1, 2 and 3 respectively. Eight taxa representing 18.6% of the total abundance were ubiquitous. The claroteid, Chrysichthys walkeri and the cichlid, Chromidotilapia guentheri were the most dominant species accounting for 19.2% and 6.0% respectively of the total catch. The species richness and general diversity were relatively higher in station 1 although Jaccard similarity index revealed that stations 1 and 3 were significantly similar while station 2 showed complete dissimilarity with stations 1 and 3. Canonical correspondence analysis indicated that dissolved oxygen, electrical conductivity, total nitrogen, Biochemical Oxygen demand and temperature were important variables structuring the overall fish assemblages. The presence of appreciable number of juveniles in this water body suggests that the Warri River is a breeding and nursery ground for fish species particularly those of brackish origin. These findings indicate that the water body is still useful as a good fishing ground for the rural communities and every effort should be put in place to ensure its protection and conservation for the production of healthy fish.Keywords: Chrysichthys walkeri, fish communities, mangrove ecosystem, physicochemical parameters, Warri River
Procedia PDF Downloads 482896 Analysis of Taxonomic Compositions, Metabolic Pathways and Antibiotic Resistance Genes in Fish Gut Microbiome by Shotgun Metagenomics
Authors: Anuj Tyagi, Balwinder Singh, Naveen Kumar B. T., Niraj K. Singh
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Characterization of diverse microbial communities in specific environment plays a crucial role in the better understanding of their functional relationship with the ecosystem. It is now well established that gut microbiome of fish is not the simple replication of microbiota of surrounding local habitat, and extensive species, dietary, physiological and metabolic variations in fishes may have a significant impact on its composition. Moreover, overuse of antibiotics in human, veterinary and aquaculture medicine has led to rapid emergence and propagation of antibiotic resistance genes (ARGs) in the aquatic environment. Microbial communities harboring specific ARGs not only get a preferential edge during selective antibiotic exposure but also possess the significant risk of ARGs transfer to other non-resistance bacteria within the confined environments. This phenomenon may lead to the emergence of habitat-specific microbial resistomes and subsequent emergence of virulent antibiotic-resistant pathogens with severe fish and consumer health consequences. In this study, gut microbiota of freshwater carp (Labeo rohita) was investigated by shotgun metagenomics to understand its taxonomic composition and functional capabilities. Metagenomic DNA, extracted from the fish gut, was subjected to sequencing on Illumina NextSeq to generate paired-end (PE) 2 x 150 bp sequencing reads. After the QC of raw sequencing data by Trimmomatic, taxonomic analysis by Kraken2 taxonomic sequence classification system revealed the presence of 36 phyla, 326 families and 985 genera in the fish gut microbiome. At phylum level, Proteobacteria accounted for more than three-fourths of total bacterial populations followed by Actinobacteria (14%) and Cyanobacteria (3%). Commonly used probiotic bacteria (Bacillus, Lactobacillus, Streptococcus, and Lactococcus) were found to be very less prevalent in fish gut. After sequencing data assembly by MEGAHIT v1.1.2 assembler and PROKKA automated analysis pipeline, pathway analysis revealed the presence of 1,608 Metacyc pathways in the fish gut microbiome. Biosynthesis pathways were found to be the most dominant (51%) followed by degradation (39%), energy-metabolism (4%) and fermentation (2%). Almost one-third (33%) of biosynthesis pathways were involved in the synthesis of secondary metabolites. Metabolic pathways for the biosynthesis of 35 antibiotic types were also present, and these accounted for 5% of overall metabolic pathways in the fish gut microbiome. Fifty-one different types of antibiotic resistance genes (ARGs) belonging to 15 antimicrobial resistance (AMR) gene families and conferring resistance against 24 antibiotic types were detected in fish gut. More than 90% ARGs in fish gut microbiome were against beta-lactams (penicillins, cephalosporins, penems, and monobactams). Resistance against tetracycline, macrolides, fluoroquinolones, and phenicols ranged from 0.7% to 1.3%. Some of the ARGs for multi-drug resistance were also found to be located on sequences of plasmid origin. The presence of pathogenic bacteria and ARGs on plasmid sequences suggested the potential risk due to horizontal gene transfer in the confined gut environment.Keywords: antibiotic resistance, fish gut, metabolic pathways, microbial diversity
Procedia PDF Downloads 135895 Challenges of Sustainable Marine Fishing in Ghana
Authors: Eric K. W. Aikins
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Traditionally, Ghana is a marine fishing country. The fishing industry dominated by artisanal marine fishing helps Ghana to meet its fish and protein requirements. Also, it provides employment for most coastal dwellers that depend on fishing as their main economic enterprise. Nonetheless, the marine fishing industry is confronted with challenges that have contributed to a declining fish production in recent past decade. Bad fishing practices and the general limited knowledge on sustainable management of fisheries resources are the limiting factors that affect sustainable fish production and sustainable marine biodiversity management in Ghana. This paper discusses the challenges and strategies for attaining and maintaining sustainable marine fishing in Ghana as well as the state of marine fishing in Ghana. It concludes that an increase in the level of involvement of local fishers in the management of fisheries resources of the country could help local fishers to employ sustainable fisheries resources exploitation methods that could result in an improvement in the spatio-economic development and wellbeing of affected fishing communities in particular and Ghana in general.Keywords: pair trawling, sargassum, spatio-economic development, sustainable marine fishing
Procedia PDF Downloads 282894 The Influence of the Aquatic Environment on Hematological Parameters in Cyprinus carpio
Authors: Andreea D. Șerban, Răzvan Mălăncuș, Mihaela Ivancia, Șteofil Creangă
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Just as air influences the quality of life in the terrestrial environment, water, as a living environment, is one of great importance when it comes to the quality of life of underwater animals, which acquires an even higher degree of importance when analyzing underwater creatures as future products for human consumption. Thus, going beyond the ideal environment, in which all water quality parameters are permanently in perfect standards for reproduction, growth, and development of fish material and customizing this study to reality, it was demonstrated the importance of reproduction, development, and growth of biological material, necessary in the population fish farms, in the same environment to gain the maximum yield that a fish farm can offer. The biological material used was harvested from 3 fish farms located at great distances from each other to have environments with different parameters. The specimens were clinically healthy at 2 years of age. Thus, the differences in water quality parameters had effects on specimens from other environments, describing large curves in their evolution in new environments. Another change was observed in the new environment, the specimens contributing with the "genetic package" to its modification, tending to a balance of the parameters studied to the values in the environment in which they lived until the time of the experiment. The study clearly showed that adaptability to the environment in which an individual has developed and grown is not valid in environments with different parameters, resulting even in the fatality of one sample during the experiment. In some specimens, the values of the studied hematological parameters were halved after the transfer to the new environment, and in others, the same parameters were doubled. The study concludes that the specimens were adapted to the environment in which they developed and grew, their descendants having a higher value of heritability only in the initial environment. It is known that heritability is influenced 50% by the genetic package of the individual and 50% by the environment, by removing the value of the environment, the duration of improvement of characters of interest will be shorter and the maximum yield of fish farms can be achieved in a smaller period.Keywords: environment, heritability, quality, water
Procedia PDF Downloads 160893 Antifungal Activity of Processed Sulfur Solution as Potential Eco-Friendly Disinfectant against Saprolegnia parasitica and Its Safety in Freshwater-Farmed Fish
Authors: Hye-Hyun Lee, Hyo-Kon Chun, Kyung-Hee Kim Kim, Mi-Hee Kim, Saet-Byul Chu, Sang-Jong Lee, Seung-Hyeop Lee, Seung-Won Yi
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Some chemicals such as malachite green, methylene blue, and copper sulfate had been used frequently as disinfectants controlling fungal infection in aquaculture. However, their carcinogenicity, mutagenicity and teratogenicity were reported in mammals. After their accumulation in food fish and its consumers was confirmed, concerns about public health has resulted in enhanced monitoring and increased demand for eco-friendly treatments. Therefore, this study aimed to evaluate safety to fish and efficacy of sulfur solution processed by effective microorganisms (EM-PSS) against Saprolegnia parasitica, for use of a potential aquatic fungicidal disinfectant. The natural sulfur purchased from Kawah Ijen volcano, East Java, Indonesia was processed by the liquid mixture consisting of following twelve effective microorganisms (Rapha-el®; Lbiotech, Jeonnam, Korea), Lactobacillus parafarraginis, L. paracasei, L. harbinensis, L. buchneri, L. perolens, L. rhamnosus, L. vaccinostercus, Acetobacter lovaniensis, A. peroxydans, Pichia fermentans, Candida ethanolica, Saccharomycopsis schoenii isolated from fermentation process of oriental medicinal herbs including green tea, privet, and puer tea. The material was applied to in vitro antifungal activity test for Saprolegnia parasitica using agar dilution method. In addition, an acute toxicity test was performed on carp (Cyprinus carpio), eel (Anguilla japonica), and mud fish (Misgurnus mizolepis) for 96 hours. After three species of fish (n=15) were accustomed to experimental water environment for three days, the EM-PSS was added to each tank as final concentrations to be 0 to 500 ppm. The fish were taken into necropsy, and the histological sections of the gill, liver, and spleen were counter-stained with hematoxylin and eosin (H-E). And hence, no observed effect concentration (NOEC) of the solution was used for taking a medicinal bath for mudfish infected by Saprolegnia parasitica in practice. The result of in vitro antifungal activity test showed the growth inhibition of the fungus at 100 ppm, which and the lower concentrations occurred no fatal case in any fish species tested until the end of the examination. The 125 ppm of the solution, however, resulted in 13.3 %, 13.3 %, and 6.3 % of mortality in carp, eel, and mudfish, respectively. But both 250 and 500 ppm of the solution leaded lethality to all population of each fish species within 24 hours. Besides, H-E staining also showed no specific evidence for toxicity in fish at lesser than 100 ppm of EM-PSS. On the other hand, as a result of field application of the solution, no growth of fungal mycelium was found in fish bodies from gross observation 5 days post treatment. In conclusion, 100ppm of EM-PSS resulted in inhibition and treatment of Saprolegnia parasitica infection. In addition, the use of EM-PSS lower than 100 ppm is safe for fish. Therefore, EM-PSS could be used as aquatic fungicide, and also may be possible to be a potential eco-friendly disinfectant in aquaculture.Keywords: antifungal activity, effective microorganism, toxicity, saprolegnia, processed sulfur solution
Procedia PDF Downloads 252892 Genome-Wide Insights into Whole Gut Microbiota of Rainbow Trout, Oncorhynchus Mykiss Associated with Changes in Dietary Composition and Temperature Regimens
Authors: John N. Idenyi, Hadimundeen Abdallah, Abigeal D. Adeyemi, Jonathan C. Eya
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Gut microbiomes play a significant role in the growth, metabolism, and health of fish. However, we know very little about the interactive effects of variations in dietary composition and temperature on rainbow trout gut microbiota. Exactly 288 rainbow trout weighing 45.6g ± 0.05 (average ± SD) were fed four isocaloric, isolipidic, and isonitrogenous diets comprising 40% crude protein and 20% crude lipid and formulated as 100 % animal-based protein (AP) and a blend of 50 fish oil (FO)/50 camelina oil (CO), 100 % AP and100 % CO, 100 % plant-based protein (PP) and a blend of 50FO/50CO or 100 % PP and 100 % CO in 14 or 18°C for 150 days. Gut content was analyzed using 16S rRNA gene and shotgun sequencing. The most abundant phyla identified regardless of diet were Tenericutes, Firmicutes, Proteobacteria, Spirochaetes, Bacteroidetes, and Actinobacteria, while Aeromonadaceae and Enterobacteriaceae were dominant families in 18°C. Moreover, gut microbes were dominated by genes relating to an amino acid, carbohydrate, fat, and energy metabolisms and influenced by temperature. The shared functional profiles for all the diets suggest that plant protein sources in combination with CO could be as good as the fish meal with 50/50 FO & CO in rainbow trout farming.Keywords: aquafeed, aquaculture, microbiome, rainbow trout
Procedia PDF Downloads 83891 Alternative Ways to Measure Impacts of Dam Closure to the Structure of Fish Communities of a Neotropical River
Authors: Ana Carolina Lima, Carlos Sérgio Agostinho, Amadeu M. V. M. Soares, Kieran A. Monaghan
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Neotropical freshwaters host some of the most biodiverse ecosystems in the world and are among the most threatened by habitat alterations. The high number of species and lack of basic ecological knowledge provides a major obstacle to understanding the effects of environmental change. We assessed the impact of dam closure on the fish communities of a neotropical river by applying simple descriptions of community organizations: Species Abundance Distribution (SAD) and Abundance Biomass Comparison (ABC) curves. Fish data were collected during three distinct time periods (one year before, one year after and five years after closure), at eight sites located downstream of the dam, in the reservoir and reservoir transition zone and upstream of the regulated flow. Dam closure was associated with changes in the structural and functional organization of fish communities at all sites. Species richness tended to increase immediately after dam closure while evenness decreased. Changes in taxonomic structure were accompanied by a change in the distribution of biomass with the proportionate contribution by smaller individuals significantly increased relative to larger individuals. Five years on, richness had fallen to below pre-closure levels at all sites, while the comparative stability of the transformed habitats was reflected by biomass-abundance distribution patterns that approximated pre-disturbance ratios. Despite initial generality, respective sites demonstrated distinct ecological responses that were related to the environmental characteristics of their transformed habitats. This simplistic analysis provides a sensitive and informative assessment of ecological conditions that highlights the impact to ecosystem process and ecological networks and has particular value in regions where detailed ecological knowledge precludes the application of traditional bioassessment methods.Keywords: ABC curves, SADs, biodiversity, damming, tropical fish
Procedia PDF Downloads 379890 The Effects of Feeding the African Catfish, Clarias gariepinus with Fermented Sweet Potato (Ipomoea batatas Lam) Peels on Growth, Nutrient Utilization and Some Physiological Responses
Authors: Adejoke Abeni Adewumi, Eunice Opeyemi Idowu, Kehinde Sunday Ayeni, Dolapo Funmi Odeyemi
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This study examined the growth, nutrient utilization, hematology, and enzyme activities of the African catfish, Clarias gariepinus, juveniles (mean weight 27.69 ±0.51g) fed diets with varying levels of fermented sweet potato (Ipomoea batatas Lam) peels (SPP), for a period of 10 weeks, in the laboratory. Five iso-caloric and iso-nitrogenous diets were formulated containing 0% (control diet), 25%, 50%, 75% and 100% SPP-maize replacements tagged diets D0, D25, D50, D75 and D100 respectively. The crude protein content of the test diets ranged from 39.04%-39.92% and crude fibre, 10.52%-11.51%. The growth response of the fish fed the four experimental diets compared favourably with the control diet, as significantly (P>0.05) higher values were observed for Mean Final Weight, Mean Weight Gain, Specific Growth Rate, Food Conversion Ratio, Protein Efficiency Ratio and Net Protein Utilization. However, fish fed diets D50 and D75 demonstrated superior growth. Carcass of fish fed experimental diets also indicated significantly higher (p>0.05) protein and lipid content compared to the initial and fish fed control diet. There was an increase in the white blood cells (WBC) and the lymphocytes as the SPP increased in the diet. The results obtained for mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH) and mean cell volume (MCV) showed that the fish fed the diet containing 75% SPP had significantly higher (p>0.05) values of MCH (48.00 pg) and MCV (155.00 fl) than the other diets. The lipase activity of the fish fed the 100% SPP meal (0.81U/mg) was significantly higher (p>0.05) than the other diets. These results show that Clarias gariepinus could tolerate up to 75% level of inclusion of fermented sweet potato peel in the diet without any deleterious effect on growth, nutrient utilization, hematological responses and enzymatic activities. Fermented sweet potato peels can conveniently replace conventional energy sources and this could become a means of recycling massive potato peel wastes being generated daily.Keywords: hematology, fermentation, carcass, growth, African catfish
Procedia PDF Downloads 13889 Valorization of Underutilized Fish Species Through a Multidisciplinary Approach
Authors: Tiziana Pepe, Gerardo Manfreda, Adriana Ianieri, Aniello Anastasio
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The sustainable exploitation of marine biological resources is among the most important objectives of the EU's Common Fisheries Policy (CFP). Currently, Europe imports about 65% of its fish products, indicating that domestic production does not meet consumer demand. Despite the availability of numerous commercially significant fish species, European consumption is concentrated on a limited number of products (e.g., sea bass, sea bream, shrimp). Many native species, present in large quantities in the Mediterranean Sea, are little known to consumers and are therefore considered ‘fishing by-products’. All the data presented so far indicate a significant waste of local resources and the overexploitation of a few fish stocks. It is therefore necessary to develop strategies that guide the market towards sustainable conversion. The objective of this work was to valorize underutilized fish species of the Mediterranean Sea through a multidisciplinary approach. To this end, three fish species were sampled: Atlantic Horse Mackerel (Trachurus trachurus), Bogue (Boops boops), and Common Dolphinfish (Coryphaena hippurus). Nutritional properties (water %, fats, proteins, ashes, salts), physical/chemical properties (TVB-N, histamine, pH), and rheological properties (color, texture, viscosity) were analyzed. The analyses were conducted on both fillets and processing by-products. Additionally, mitochondrial DNA (mtDNA) was extracted from the muscle of each species. The mtDNA was then sequenced using the Illumina NGS technique. The analysis of nutritional properties classified the fillets of the sampled species as lean or semi-fat, as they had a fat content of less than 3%, while the by-products showed a higher lipid content (2.7-5%). The protein percentage for all fillets was 22-23%, while for processing by-products, the protein concentration was 18-19% for all species. Rheological analyses showed an increase in viscosity in saline solution in all species, indicating their potential suitability for industrial processing. High-quality and quantity complete mtDNA was extracted from all analyzed species. The complete mitochondrial genome sequences were successfully obtained and annotated. The results of this study suggest that all analyzed species are suitable for both human consumption and feed production. The sequencing of the complete mtDNA and its availability in international databases will be useful for accurate phylogenetic analysis and proper species identification, even in prepared and processed products. Underutilized fish species represent an important economic resource. Encouraging their consumption could limit the phenomenon of overfishing, protecting marine biodiversity. Furthermore, the valorization of these species will increase national fish production, supporting the local economy, cultural, and gastronomic tradition, and optimizing the exploitation of Mediterranean resources in accordance with the CFP.Keywords: mtDNA, nutritional analysis, sustainable fisheries, underutilized fish species
Procedia PDF Downloads 17888 Mesozooplankton in the Straits of Florida: Patterns in Biomass and Distribution
Authors: Sharein El-Tourky, Sharon Smith, Gary Hitchcock
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Effective fisheries management is necessarily dependent on the accuracy of fisheries models, which can be limited if they omit critical elements. One critical element in the formulation of these models is the trophic interactions at the larval stage of fish development. At this stage, fish mortality rates are at their peak and survival is often determined by resource limitation. Thus it is crucial to identify and quantify essential prey resources and determine how they vary in abundance and availability. The main resources larval fish consume are mesozooplankton. In the Straits of Florida, little is known about temporal and spatial variability of the mesozooplankton community despite its importance as a spawning ground for fish such as the Blue Marlin. To investigate mesozooplankton distribution patterns in the Straits of Florida, a transect of 16 stations from Miami to the Bahamas was sampled once a month in 2003 and 2004 at four depths. We found marked temporal and spatial variability in mesozooplankton biomass, diversity, and depth distribution. Mesozooplankton biomass peaked on the western boundary of the SOF and decreased gradually across the straits to a minimum at eastern stations. Midcurrent stations appeared to be a region of enhanced year-round variability, but limited seasonality. Examination of dominant zooplankton groups revealed groups could be parsed into 6 clusters based on abundance. Of these zooplankton groups, copepods were the most abundant zooplankton group, with the 20 most abundant species making up 86% of the copepod community. Copepod diversity was lowest at midcurrent stations and highest in the Eastern SOF. Interestingly, one copepods species, previously identified to compose up to 90% of larval blue marlin and sailfish diets in the SOF, had a mean abundance of less than 7%. However, the unique spatial and vertical distribution patterns of this copepod coincide with peak larval fish spawning periods and larval distribution, suggesting an important relationship requiring further investigation.Keywords: mesozooplankton biodiversity, larval fish diet, food web, Straits of Florida, vertical distribution, spatiotemporal variability, cross-current comparisons, Gulf Stream
Procedia PDF Downloads 547887 Immunostimulatory Response of Supplement Feed in Fish against Aeromonas hydrophila
Authors: Shikha Rani, Neeta Sehgal, Vipin Kumar Verma, Om Prakash
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Introduction: Fish is an important protein source for humans and has great economic value. Fish cultures are affected due to various anthropogenic activities that lead to bacterial and viral infections. Aeromonas hydrophila is a fish pathogenic bacterium that causes several aquaculture outbreaks throughout the world and leads to huge mortalities. In this study, plants of no commercial value were used to investigate their immunostimulatory, antioxidant, anti-inflammatory, anti-bacterial, and disease resistance potential in fish against Aeromonas hydrophila, through fish feed fortification. Methods: The plant was dried at room temperature in the shade, dissolved in methanol, and analysed for biological compounds through GC-MS/MS. DPPH, FRAP, Phenolic, and flavonoids were estimated following standardized protocols. In silico molecular docking was also performed to validate its broad-spectrum activities based on binding affinity with specific proteins. Fish were divided into four groups (n=6; total 30 in a group): Group 1, non-challenged fish (fed on a non-supplemented diet); Group 2, fish challenged with bacteria (fed on a non-supplemented diet); Group 3 and 4, fish challenged with bacteria (A. hydrophila) and fed on plant supplemented feed at 2.5% and 5%. Blood was collected from the fish on 0, 7th, 14th, 21st, and 28th days. Serum was separated for glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase assay (ALP), lysozyme activity assay, superoxide dismutase assay (SOD), lipid peroxidation assay (LPO) and molecular parameters (including cytokine levels) were estimated through ELISA. The phagocytic activity of macrophages from the spleen and head kidney, along with quantitative analysis of immune-related genes, were analysed in different tissue samples. The digestive enzymes (Pepsin, Trypsin, and Chymotrypsin) were also measured to evaluate the effect of plant-supplemented feed on freshwater fish. Results and Discussion: GC-MS/MS analysis of a methanolic extract of plant validated the presence of key compounds having antioxidant, anti-inflammatory, anti-bacterial, anti-inflammatory, and immunomodulatory activities along with disease resistance properties. From biochemical investigations like ABTS, DPPH, and FRAP, the amount of total flavonoids, phenols, and promising binding affinities towards different proteins in molecular docking analysis helped us to realize the potential of this plant that can be used for investigation in the supplemented feed of fish. Measurement liver function tests, ALPs, oxidation-antioxidant enzyme concentrations, and immunoglobulin concentrations in the experimental groups (3 and 4) showed significant improvement as compared to the positive control group. The histopathological evaluation of the liver, spleen, and head kidney supports the biochemical findings. The isolated macrophages from the group fed on supplemented feed showed a higher percentage of phagocytosis and a phagocytic index, indicating an enhanced cell-mediated immune response. Significant improvements in digestive enzymes were also observed in fish fed on supplemented feed, even after weekly challenges with bacteria. Hence, the plant-fortified feed can be recommended as a regular feed to enhance fish immunity and disease resistance against the Aeromonas hydrophila infection after confirmation from the field trial.Keywords: immunostimulation, antipathogen, plant fortified feed, macrophages, GC-MS/MS, in silico molecular docking
Procedia PDF Downloads 77886 Chemical Speciation and Bioavailability of Some Essential Metal Ions In Different Fish Organs at Lake Chamo, Ethiopia
Authors: Adane Gebresilassie Hailemariam, Belete Yilma Hirpaye
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The enhanced concentrations of heavy metals, especially in sediments, may indicate human-induced perturbations rather than natural enrichment through geological weathering. Heavy metals are non-biodegradable, persist in the environment, and are concentrated up to the food chain, leading to enhanced levels in the liver and muscle tissues of fishes, aquatic bryophytes, and aquatic biota. Marine organisms, in general fish in particular, accumulate metals to concentrations many times higher than present in water or sediment as they can take up metals in their organs and concentrate at different levels. Thus, metals acquired through the food chain due to pollution are potential chemical hazards, threatening consumers. The Nile tilapia (oreochromic niloticus), catfish (clarius garpinus), and water samples were collected from five sampling sites, namely, inlet-1, inlet-2, center, outlet-1 and outlet-2 of Lake Chamo. The concentration of major and trace metals Na, K, Mg, Ca, Cr, Co, Ni, Mn and Cu in the two fish muscles, gill and liver, was determined using an atomic absorption spectrometer (AAS) and flame photometer (FP). Metal concentrations in the water have also been evaluated within the two consecutive seasons, winter (dry) and spring (wet). The results revealed that the concentration of those metals in Tilapia’s (O. niloticus) muscle, gill, and liver were Na 44.5, 35.1, 28, Mg 2.8, 8.41, 4.61, K 43, 32, 30, Ca 1.5, 6.0, 5.5, Cr 0.91, 1.2, 3.5, Co 3.0, 2.89, 2.62, Ni 0.94, 1.99, 2.2, Mn 1.23, 1.51, 1.6 and Cu 1.1, 1.99, 3.5 mg kg-1 respectively and in catfish’s muscle, gill and liver Na 25, 39, 41.5, Mg 4.8, 2.87, 6, K 29, 38, 40, Ca 2.5, 8.10, 3.0, Cr 0.65, 3.5, 5.0, Co 2.62, 1.86, 1.73, Ni 1.10, 2.3, 3.1, Mn 1.54, 1.57, 1.59 and Cu 1.01, 1.10, 3.70 mg kg-1 respectively. The highest accumulation of Na and K were observed for tilapia muscle and catfish gill, Mg and Ca got higher in tilapia gill and catfish liver, while Co is higher in muscle of the two fish. The Cr, Ni, Mn and Cu levels were higher in the livers of the two fish species. In conculusion, metal toxicity through food chain is the current dangerous issue for human and othe animals. This needs deep focus to promot the health of living animals. The Details of the work are going to be discussed at the conference.Keywords: bioaccumulation, catfish, essential metals, nile tilapia
Procedia PDF Downloads 69885 Effect of Question Answer Relationship (QARs) in Science Reading on the Academic Achievement of Students in Biology
Authors: Helen Ngozi Ibe, Chimmuanya Ezere
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The study investigated the effect of Question Answer Relationships (QARs) in science reading on secondary school students’ achievement in Biology in Owerri Education Zone II of Imo State. The study adopted a quasi-experimental design and was guided by two research questions and two hypotheses. The sample comprised of 67 SS2 Biology students. The sample was drawn using random sampling technique. One researcher made instrument titled: Biology Achievement Test (BAT) was used for collecting the data of the study. The reliability of the instrument was established using Kuder Richardson formula (KR-20) which yielded a reliability index of 0.85 and Cronbach alpha for the BSIRS with an index of 0.71. Research questions were answered using mean and standard deviation. T-test statistics was used to test the hypotheses at 0.05 level of significance. The major findings are that students exposed to QARs strategy in science reading had higher achievement mean scores in biology than students in the control group; there is no significant difference between the achievement mean scores of male and female students exposed to QARs. The researchers recommended that science teachers should teach students the Question Answer Relationship reading strategy and that science students should endeavour to use the question - answer relationship reading strategy in classroom and individual science reading in order to enhance high academic achievement in the subjects being read.Keywords: academic achievement, biology, science reading, question-answer relationship
Procedia PDF Downloads 109884 The Monogeneans of the Genus Lamellodiscus, Parasites of Sparidae Fish of the Genus Dentex on the Coasts of Dakar (Sénégal)
Authors: Sikhou Drame, Arfang Diamanka
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This study focuses on an examination of the Monogenea community of the Lamellodiscus genus, parasites of teleost fish of the Dentex genus (Sparidae): Dentex angolensis, Dentex canariensis, Dentex macrophthalmus, and Dentex maroccanus from two landing sites in Dakar: Soumbédioune landing and Hann Bel Air landing. Observing the morpho-anatomical criteria of the monogeneans collected from all host species reveals the presence of 6 species of the Lamellodiscus genus (Monogenea, Diplectanidae): Lamellodiscus euzeti in Dentex canariensis, Lamellodiscus dentexi, Lamellodiscus toguebayei, Lamellodiscus triacies, and Lamellodiscus vicinus in Dentex macrophthalmus; Lamellodiscus crampus in its usual host Dentex marrocanus and we found it in Dentex angolensis. The results of the study on the distribution of parasitic indices in the studied host species show that infestation rates and parasite burdens vary from one host species to another and from one season to another. However, it is during the hot season that the values of infestation intensity and abundance are highest. Additionally, we note that Dentex canariensis records the highest parasite burdens in both locations.Keywords: lamellodiscus, fish, dentex, Dakar, Monogenea
Procedia PDF Downloads 34883 Assessment of Sperm Aneuploidy Using Advanced Sperm Fish Technique in Infertile Patients
Authors: Archana. S, Usha Rani. G, Anand Balakrishnan, Sanjana.R, Solomon F, Vijayalakshmi. J
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Background: There is evidence that male factors contribute to the infertility of up to 50% of couples, who are evaluated and treated for infertility using advanced assisted reproductive technologies. Genetic abnormalities, including sperm chromosome aneuploidy as well as structural aberrations, are one of the major causes of male infertility. Recent advances in technology expedite the evaluation of sperm aneuploidy. The purpose of the study was to de-termine the prevalence of sperm aneuploidy in infertile males and the degree of association between DNA fragmentation and sperm aneuploidy. Methods: In this study, 75 infertile men were included, and they were divided into four abnormal groups (Oligospermia, Terato-spermia, Asthenospermia and Oligoasthenoteratospermia (OAT)). Men with children who were normozoospermia served as the control group. The Fluorescence in situ hybridization (FISH) method was used to test for sperm aneuploidy, and the Sperm Chromatin Dispersion Assay (SCDA) was used to measure the fragmentation of sperm DNA. Spearman's correla-tion coefficient was used to evaluate the relationship between sperm aneuploidy and sperm DNA fragmentation along with age. P < 0.05 was regarded as significant. Results: 75 partic-ipants' ages varied from 28 to 48 years old (35.5±5.1). The percentage of spermatozoa bear-ing X and Y was determined to be statistically significant (p-value < 0.05) and was found to be 48.92% and 51.18% of CEP X X 1 – nucish (CEP XX 1) [100] and CEP Y X 1 – nucish (CEP Y X 1) [100]. When compared to the rate of DNA fragmentation, it was discovered that infertile males had a greater frequency of sperm aneuploidy. Asthenospermia and OAT groups in sex chromosomal aneuploidy were significantly correlated (p<0.05). Conclusion: Sperm FISH and SCDA assay results showed increased sperm aneuploidy frequency, and DNA fragmentation index in infertile men compared with fertile men. There is a significant relationship observed between sperm aneuploidy and DNA fragmentation in OAT patients. When evaluating male variables and idiopathic infertility, the sperm FISH screening method can be used as a valuable diagnostic tool.Keywords: ale infertility, dfi (dna fragmentation assay) (scd-sperm chromatin dispersion).art (artificial reproductive technology), trisomy, aneuploidy, fish (fluorescence in-situ hybridization), oat (oligoasthoteratospermia)
Procedia PDF Downloads 47882 Assessment of Women Involvement in Fishing Activities: A Case Study of Epe and Ibeju Lekki LGA, Lagos
Authors: Temitope Adewale, Oladapo Raji
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The study was designed to investigate the assessment of women's involvement in fishing. In order to give the study a direction, five research questions, as well as two hypotheses, were postulated, and a total of fifty (50) respondents each were selected from two local government areas for the study. This brings a total of one hundred (100) respondents selected from these local government areas in Lagos state. The outcome of the finding indicates that the percentage of the respondents’ age, 49% was between 31 and 35 years, 56% has a working experience of 6-10 years, 61% were married, 69% had secondary education as their educational level. However, findings show that socio-economic characteristics (x2 =15.504, df=6, p < 0.05) and income (r=0.83, p < 0.05) have a significant relationship on the fishing. It was established that the Women in Fish production/processing were faced with a lot of constraints such as high cost of inputs, inadequate electricity supply, lack of adequate capital, non-availability of the improved oven, non-availability of extension agents, inadequate fish landing, lack of transportation facilities, lack of training on financial management and loan acquisition which affected the level of output of women in Fish processing adversely.Keywords: women, fishing, agriculture, Lagos
Procedia PDF Downloads 132881 In vivo Inhibition and Restoration of Acetyl Cholinesterase Activities in Induced Clarias Gariepinus
Authors: T. O. Ikpesu, I. Tongo, A. Ariyo
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This study was conducted to assess the effects of an organophosphate pesticide glyphosate formulation on neurological enzymes in the brain, liver and serum of juvenile Clarias gariepinus, and also to examine the antidotal prospect of Garcinia kola seeds extract. The fish divided into five groups were exposed to different treatments of glyphosate formulation and Garcinia kola seeds extract. Acetyl cholinesterase activities in the brain, liver and serum of the fish were estimated in the experimental and control fishes on day -7, 14, 21 and of 28 by spectrophotometrical methods. The enzyme was significantly (p < 0.05) inhibited in glyphosate formulation test. The inhibition percentages of AChE ranged for the brain, liver and serum between 40.7–59.4%, 50-57% and 27.5–51.3%, respectively. The aberrated parameters were recovered in G. kola seeds extract treated aquaria, and was dose and time dependent. The present study demonstrated that in vivo glyphosate formulation exposure caused AChE inhibition in the brain, liver and the serum. The brain tissue, however, might be suggested as a good indicator tissue for aquatic pollutants exposure in the fish and G. kola seeds extract has shown to be a good remedy for neurology restoration in a noxious circumstance. The findings has shown that xenobiotics could be eliminated from aquatic organisms, especially fish, and could be put into practice in areas at risk of pollutants. This approach can reduce the risks of biomagnification of poison in sea food. Hence, formulation of this plant extracts into capsule should be encouraged and supported.Keywords: glyphosate, Clarias gariepinus, brain, Garcinia kola, acetyl cholinesterase, enzymes
Procedia PDF Downloads 386880 Reproductive Biology and Lipid Content of Albacore Tuna (Thunnus alalunga) in the Western Indian Ocean
Authors: Zahirah Dhurmeea, Iker Zudaire, Heidi Pethybridge, Emmanuel Chassot, Maria Cedras, Natacha Nikolic, Jerome Bourjea, Wendy West, Chandani Appadoo, Nathalie Bodin
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Scientific advice on the status of fish stocks relies on indicators that are based on strong assumptions on biological parameters such as condition, maturity and fecundity. Currently, information on the biology of albacore tuna, Thunnus alalunga, in the Indian Ocean is scarce. Consequently, many parameters used in stock assessment models for Indian Ocean albacore originate largely from other studied stocks or species of tuna. Inclusion of incorrect biological data in stock assessment models would lead to inappropriate estimates of stock status used by fisheries manager’s to establish future catch allowances. The reproductive biology of albacore tuna in the western Indian Ocean was examined through analysis of the sex ratio, spawning season, length-at-maturity (L50), spawning frequency, fecundity and fish condition. In addition, the total lipid content (TL) and lipid class composition in the gonads, liver and muscle tissues of female albacore during the reproductive cycle was investigated. A total of 923 female and 867 male albacore were sampled from 2013 to 2015. A bias in sex-ratio was found in favour of females with fork length (LF) <100 cm. Using histological analyses and gonadosomatic index, spawning was found to occur between 10°S and 30°S, mainly to the east of Madagascar from October to January. Large females contributed more to reproduction through their longer spawning period compared to small individuals. The L50 (mean ± standard error) of female albacore was estimated at 85.3 ± 0.7 cm LF at the vitellogenic 3 oocyte stage maturity threshold. Albacore spawn on average every 2.2 days within the spawning region and spawning months from November to January. Batch fecundity varied between 0.26 and 2.09 million eggs and the relative batch fecundity (mean standard deviation) was estimated at 53.4 ± 23.2 oocytes g-1 of somatic-gutted weight. Depending on the maturity stage, TL in ovaries ranged from 7.5 to 577.8 mg g-1 of wet weight (ww) with different proportions of phospholipids (PL), wax esters (WE), triacylglycerol (TAG) and sterol (ST). The highest TL were observed in immature (mostly TAG and PL) and spawning capable ovaries (mostly PL, WE and TAG). Liver TL varied from 21.1 to 294.8 mg g-1 (ww) and acted as an energy (mainly TAG and PL) storage prior to reproduction when the lowest TL was observed. Muscle TL varied from 2.0 to 71.7 g-1 (ww) in mature females without a clear pattern between maturity stages, although higher values of up to 117.3 g-1 (ww) was found in immature females. TL results suggest that albacore could be viewed predominantly as a capital breeder relying mostly on lipids stored before the onset of reproduction and with little additional energy derived from feeding. This study is the first one to provide new information on the reproductive development and classification of albacore in the western Indian Ocean. The reproductive parameters will reduce uncertainty in current stock assessment models which will eventually promote sustainability of the fishery.Keywords: condition, size-at-maturity, spawning behaviour, temperate tuna, total lipid content
Procedia PDF Downloads 254879 Anisakidosis in Turkey: Serological Survey and Risk for Humans
Authors: E. Akdur Öztürk, F. İrvasa Bilgiç, A. Ludovisi , O. Gülbahar, D. Dirim Erdoğan, M. Korkmaz, M. Á. Gómez Morales
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Anisakidosis is a zoonotic human fish-borne parasitic disease caused by accidental ingestion of anisakid third-stage larvae (L3) of members of the Anisakidae family present in infected marine fish or cephalopods. Infection with anisakid larvae can lead to gastric, intestinal, extra-gastrointestinal and gastroallergic forms of the disease. Anisakid parasites have been reported in almost all seas, particularly in the Mediterranean Sea. There is a remarkably high level of risk exposure to these zoonotic parasites as they are present in economically and ecologically important fish of Europe. Anisakid L3 larvae have been also detected in several fish species from the Aegean Sea. Turkey is a peninsular country surrounded by Black, Aegean and the Mediterranean Sea. In this country, fishing habit and fishery product consumption are highly common. In recent years, there was also an increase in the consumption of raw fish due to the increasing interest in the cuisine of the Far East countries. In different regions of Turkey, A. simplex (inMerluccius Merluccius Scomber japonicus, Trachurus mediterraneus, Sardina pilchardus, Engraulis encrasicolus, etc.), Anisakis spp., Contraceucum spp., Pseudoterronova spp. and, C. aduncum were identified as well. Although it is accepted both the presence of anisakid parasites in fish and fishery products in Turkey and the presence of Turkish people with allergic manifestations after fish consumption, there are no reports of human anisakiasis in this country. Given the high prevalence of anisakid parasites in the country, the absence of reports is likely not due to the absence of clinical cases rather to the unavailability of diagnostic tools and the low awareness of the presence of this infection. The aim of the study was to set up an IgE-Western Blot (WB) based test to detect the anisakidosis sensitization among Turkish people with a history of allergic manifestation related to fish consumption. To this end, crude worm antigens (CWA) and allergen enriched fraction (50-66% ) were prepared from L3 of A. simplex (s.l.) collected from Lepidopus caudatus fished in the Mediterranean Sea. These proteins were electrophoretically separated and transferred into the nitrocellulose membranes. By WB, specific proteins recognized by positive control serum samples from sensitized patients were visualized on nitrocellulose membranes by a colorimetric reaction. The CWA and 50–66% fraction showed specific bands, mainly due to Ani s 1 (20-22 kD) and Ani s 4 (9-10 kD). So far, a total of 7 serum samples from people with allergic manifestation and positive skin prick test (SPT) after fish consumption, have been tested and all of them resulted negative by WB, indicating the lack of sensitization to anisakids. This preliminary study allowed to set up a specific test and evidence the lack of correlation between both tests, SPT and WB. However, the sample size should be increased to estimate the anisakidosis burden in Turkish people.Keywords: anisakidosis, fish parasite, serodiagnosis, Turkey
Procedia PDF Downloads 131878 Management Challenges and Product Quality of Fish Farms in Greece
Authors: S. Anastasiou, C. Nathanailides, S. Logothetis, G. Kanlis
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The Greek aquaculture industry is second most important economic sector for the growth of the Greek Economy. The purpose of the present work is to present some data for the management challenges that the Aquaculture industry in Greece is currently facing. Currently the Greek aquaculture industry is going through a series of mergers and restructure. The financial status of the different aquaculture companies, the working conditions and management practices may vary according to lending exposure, market mix, company size, and technological parameters of the different fish farm units and rearing systems. Frequently, the aquaculture personnel are exposed to harsh environmental conditions and to occupational risk. Furthermore, there is pressure on the personnel of fish farms to constantly improve their production efficiency and to enhance their work skills to the new methods and practices which are adopted by the aquaculture industry. There is some data to suggest the existence of gender inequality in the workforce of Greek fish farms. Women are paid less, frequently absent higher managerial positions and most of the male workmates consider the job to harsh for women. Nevertheless, high level of job satisfaction was observed in both men and women. This high level of job satisfaction of the aquaculture personnel can be attributed, at least partially, to the nature of the work which has a very distinct working environment but most of the staff has very positive experiences with the interaction with their workmates and the satisfaction of being in a business which always exceeds its production target. Indeed, there is some evidence to suggest that the Greek aquaculture industry is always exceeding its production targets, while it is rapidly adopting and improving new technology, constantly improving of human resources management practices, which include constant training of the staff, very good communication channels between management and the personnel and reducing the risk of occupational hazard to the aquaculture personnel. All these parameters of management may have a determining role for the volume and quality of the production and future of this sector in Greece.Keywords: aquaculture, fish quality, management, production targets
Procedia PDF Downloads 437877 Juvenile Fish Associated with Pondweed and Charophyte Habitat: A Case Study Using Upgraded Pop-up Net in the Estuarine Part of the Curonian Lagoon
Authors: M. Bučas, A. Skersonas, E. Ivanauskas, J. Lesutienė, N. Nika, G. Srėbalienė, E. Tiškus, J. Gintauskas, A.Šaškov, G. Martin
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Submerged vegetation enhances heterogeneity of sublittoral habitats; therefore, macrophyte stands are essential elements of aquatic ecosystems to maintain a diverse fish fauna. Fish-habitat relations have been extensively studied in streams and coastal waters, but in lakes and estuaries are still underestimated. The aim of this study is to assess temporal (diurnal and seasonal) patterns of fish juvenile assemblages associated with common submerged macrophyte habitats, which have significantly spread during the recent decade in the upper littoral part of the Curonian Lagoon. The assessment was performed by means of an upgraded pop-up net approach resulting in much precise sampling versus other techniques. The optimal number of samples (i.e., pop-up nets) required to cover>80% of the total number of fish species depended on the time of the day in both study sites: at least 7and 9 nets in the evening (18-24 pm) in the Southern and Northern study sites, respectively. In total, 14 fish species were recorded, where perch and roach dominated (respectively 48% and 24%). From multivariate analysis, water salinity and seasonality (temperature or sampling month) were primary factors determining fish assemblage composition. The southern littoral area, less affected by brackish water conditions, hosted a higher number of species (13) than in the Northern site (8). In the latter site, brackish water tolerant species (three-spined and nine-spined sticklebacks, spiny loach, roach, and round goby) were more abundant than in the Southern site. Perch and ruffe dominated in the Southern site. Spiny loach and nine-spined stickleback were more frequent in September, while ruffe, perch, and roach occurred more in July. The diel dynamics of the common species such as perch, roach, and ruffe followed the general pattern, but it was species specific and depended on the study site, habitat, and month. The species composition between macrophyte habitats did not significantly differ; however, it differed from the results obtained in 2005 at both study sites indicating the importance of expanded charophyte stands during the last decade in the littoral zone.Keywords: diel dynamics, charophytes, pondweeds, herbivorous and benthivorous fishes, littoral, nursery habitat, shelter
Procedia PDF Downloads 179876 Applying EzRAD Method for SNPs Discovery in Population Genetics of Freshwater and Marine Fish in the South of Vietnam
Authors: Quyen Vu Dang Ha, Oanh Truong Thi, Thuoc Tran Linh, Kent Carpenter, Thinh Doan Vu, Binh Dang Thuy
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Enzyme restriction site associated DNA (EzRAD) has recently emerged as a promising genomic approach for exploring fish genetic diversity on a genome-wide scale. This is a simplified method for genomic genotyping in non-model organisms and applied for SNPs discovery in the population genetics of freshwater and marine fish in the South of Vietnam. The observations of regional-scale differentiation of commercial freshwater fish (smallscale croakers Boesemania microlepis) and marine fish (emperor Lethrinus lentjan) are clarified. Samples were collected along Hau River and coastal area in the south and center Vietnam. 52 DNA samples from Tra Vinh, An Giang Province for Boesemania microlepis and 34 DNA samples of Lethrinus lentjan from Phu Quoc, Nha Trang, Da Nang Province were used to prepare EzRAD libraries from genomic DNA digested with MboI and Sau3AI. A pooled sample of regional EzRAD libraries was sequenced using the HiSeq 2500 Illumina platform. For Boesemania microlepis, the small scale population different from upstream to downstream of Hau river were detected, An Giang population exhibited less genetic diversity (SNPs per individual from 14 to 926), in comparison to Tra Vinh population (from 11 to 2172). For Lethrinus lentjan, the result showed the minor difference between populations in the Northern and the Southern Mekong River. The numbers of contigs and SNPs vary from 1315 to 2455 and from 7122 to 8594, respectively (P ≤ 0.01). The current preliminary study reveals regional scale population disconnection probably reflecting environmental changing. Additional sampling and EzRad libraries need to be implemented for resource management in the Mekong Delta.Keywords: Boesemania microlepis, EzRAD, Lethrinus lentjan, SNPs
Procedia PDF Downloads 498875 Determination of Proximate, Mineral, and Heavy Metal Contents of Fish from the Lower River Niger at Agenebode, Edo State, Nigeria
Authors: Agbugui M. O., Inobeme A.
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Fish constitutes a vital component of human diets due to their rich nutritional compositions. They serve as a remarkable source of proteins, vitamins, and fatty acids, which are indispensable for the effective growth and development of humans. The need to explore the nutritional compositions of various species of fish in different water bodies becomes paramount. Presently, consumer concern is not just on food's nutritional value but also on the safety level. Environmental contamination by heavy metals has become an issue of pressing concern in recent times. Heavy metals, due to their ubiquitous nature, are found in various water bodies as they are released from various anthropogenic activities. This work investigated the proximate compositions, mineral contents, and heavy metals concentrations of four different species of fish (P. annectens, L. niloticus, G. niloticus, and H. niloticus) collected from the lower Niger at Agenebode using standard procedures. The highest protein contents were in Gymnarchus niloticus (37.32%), while the least was in Heterotis niloticus (20.41%). Protopterus annectens had the highest carbohydrate content (34.55%), while Heterotis niloticus had the least (12.24%). The highest lipid content (14.41%) was in Gymnarchus niloticus. The highest concentration of potassium was 21.00 ppm. The concentrations of heavy metals in ppm ranged from 0.01 – 1.4 (Cd), 0.07 – 2.89 (Pb), 0.02 – 16.4 (Hg), 0.88 – 5.1 (Cu) and 1.2 – 8.23 (Zn). The concentrations of Hg, Cd and Pb in some of the samples investigated were higher than the permissible limits based on international standards. There is a pressing need for further study focusing on various species of animals and plants in the area due to the alarming contents of these metals; remedial measures could also be ensured for safety.Keywords: trace metals, nutritional value, human health, crude protein, lipid content
Procedia PDF Downloads 86874 Dry-Extrusion of Asian Carp, a Sustainable Source of Natural Methionine for Organic Poultry Production
Authors: I. Upadhyaya, K. Arsi, A. M. Donoghue, C. N. Coon, M. Schlumbohm, M. N. Riaz, M. B. Farnell, A. Upadhyay, A. J. Davis, D. J. Donoghue
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Methionine, a sulfur containing amino acid, is essential for healthy poultry production. Synthetic methionine is commonly used as a supplement in conventional poultry. However, for organic poultry, a natural, cost effective source of methionine that can replace synthetic methionine is unavailable. Invasive Asian carp (AC) are a potential natural methionine source; however, there is no proven technology to utilize this fish methionine. Commercially available rendering is environmentally challenging due to the offensive smell produced during production. We explored extrusion technology as a potential cost effective alternative to fish rendering. We also determined the amino acid composition, digestible amino acids and total metabolizable energy (TMEn) for the extruded AC fish meal. Dry extrusion of AC was carried out by mixing the fish with soybean meal (SBM) in a 1:1 proportion to reduce high moisture in the fishmeal using an Insta Pro Jr. dry extruder followed by drying and grinding of the product. To determine the digestible amino acids and TMEn of the extruded product, a colony of cecectomized Bovans White Roosters was used. Adult roosters (48 weeks of age) were fasted for 30 h and tube fed 35 grams of 3 treatments: (1) extruded AC fish meal, (2) SBM and (3) corn. Excreta from each individual bird was collected for the next 48 h. An additional 10 unfed roosters served as endogenous controls. The gross energy and protein content of the feces from the treatments were determined to calculate the TMEn. Fecal samples and treatment feeds were analyzed for amino acid content and percent digestible amino acid. Results from the analysis suggested that addition of Asian carp increased the methionine content of SBM from 0.63 to 0.83%. Also, the digestibility of amino acid and the TMEn values were greater for the AC meal with SBM than SBM alone. The dry extruded AC meal analysis is indicative that the product can replace SBM alone and enhance natural methionine in a standard poultry ration. The results from feed formulation using different concentrations of the AC fish meal depict a potential diet which can supplement the required methionine content in organic poultry production.Keywords: Asian carp, extrusion, natural methionine, organic poultry
Procedia PDF Downloads 211873 Length Weight Relationship and Relative Condition Factor of Atropus atropos (Bloch and Schneider, 1801) from Mangalore Coast, India
Authors: D. P. Rajesh, H. N. Anjanayappa, P. Nayana, S. Benakappa
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The present study deals with length-weight relationship of Atropus atropos for which no information is available on this aspect from Mangalore coast. Therefore the present investigation was undertaken. Fish samples were collected from fish landing center (Mangalore) and fish market. The regression co-efficient of male was found to be lower than female. From this observation it may be opined that female gained more weight with increase in length compared to male. Data on seasonal variation in condition factor (Kn) showed that Kn values were more or less similar in both the sexes, indicating almost identical metabolic activity. Gonadal development and high feeding intensity are the factors which influenced the condition factor. The seasonal fluctuations in the relative condition factor of both the sexes could be attributed to the sexual cycle, food intake and environmental factors. From the present study, it can be inferred that the variation in the condition of Atropus atropos was due to feeding activity and gonadal maturity.Keywords: Atropus atropos, length-weight relationship, Mangalore coast, relative condition factor, Kn
Procedia PDF Downloads 337