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Sample records for culuwiya tilapiae nasir

  1. Khajeh Nasir al-Din al-Tusi’s Role in the Interaction of Triple Paradigms of Islamic Philosophy

    Directory of Open Access Journals (Sweden)

    r Mohammadzadeh

    2013-09-01

    Full Text Available Our aim in this article is to investigate Khajeh Nasir`s effective role in emergence, growth and development of triple paradigms of Islamic philosophy, that are, Masha’, Ishraq and al-Hekmah al-Motealiyeh. Thus, first we present a summary of the meaning of “paradigm” and then discuss Tusi`s role in the development of triple paradigms of Islamic philosophy. We believe that, by using an interactive approach, Khajeh Nasir has attained a new approach to understand the paradigms. He is the first thinker in Islamic world who created a constructive and effective interaction between two paradigms of Masha’ and Ishraq, and paved the way for the emergence of al-Hekmah al-Motealiyeh. This can be explained with regard to either the conceptualization of al-Hekmat al-Motealiyeh or epistemological approach. Al-Hekmah Al-Motealiyah was influenced a lot by Tusi.

  2. The Comparative Study of Morals and Democracy and Their Effect on the Behavioral Reflections of Khawaja Nasir Al-Din Tusi and John Dewey

    Science.gov (United States)

    Mirzaei, Khalil; Golestani, Sayyed Hashem; Vaezi, Sayyed Hossain

    2016-01-01

    This study was aimed at comparatively analyzing morals and democracy from John Dewey and Khawaja Nasir al-Din Tusi's viewpoint. It also sought the effect of the two philosophers' viewpoint about morals and democracy and behavioral reflections. The purpose of this study was also to become familiar with the effect of morals and democracy on…

  3. La imagen del Miramamolín al Nasir (1199-1213 en las fuentes cristianas del siglo XIII

    Directory of Open Access Journals (Sweden)

    Alvira Cabrer, Martín

    1996-12-01

    Full Text Available In contemporary Christian sources, the images of the Almohade calif Muhammad al-Nasir, the defeated Miramamolin in great battle of Las Navas de Tolosa (1212, make possible to notice mental and ideological notions shared by the Medieval West of Xlllth Century. For the Europeans, the fear to the powerful Almohade Empire reflected by sources was employed by some chroniclers, with a propagandistic intention, to improve Spanish Crusade or disparage the political and religious enemies of Papacy. For the Spaniards, the al-Nasir's image refered to his role in the campaign of 1212. About the Miramamolin, the chroniclers projected the image of "the other one" supported by the ideology of war in Christian West. Thus, the victorious king's virtues, Alphonse VIII of Castille —faith, humility, courage, loyalty and generosity— opposed to the defeated calif's vices —unbelief, pride, cowardice, disloyalty and covetousness—, generating two opposite models wich purpose was, on the one hand, to exalte the victorious Christians and, on the other hand, to create an explicative recourse of religious and providencial character for, in the chroniclers's mentality, to make sense out of the cause of Muslim desaster in the battle of 1212.[fr] Dans les sources chrétiennes contemporaines, les images du caliphe almohade Muhammad al-Nasir, le Miramamolin vaincu dans la grinde bataille de Las Navas de Tolosa (1212, permettent d'observer des notions mentales et idéologiques partagées par l'Occident médiéval du XIIIe siècle. Pour l'Europe en général, la crainte au puissant Empire Almohade que reflètent les sources, servit à certains chroniqueurs, avec un esprit propagandiste, à favoriser la Croisade d'Espagne ou à enlever le prestige aux ennemis religieuse et politiques de la Papauté. Pour les espagnols, l'image de al-Nasir se centra en son rôle pendant la campagne de 1212. Sur le Miramamolin, les chroniqueurs projetèrent l'image de "l'autre" qui soutenait

  4. Dynastic Marriage of Mamluk Sultan of Egypt al-Nasir and Princess Tulunbay according to Medieval Arab Chronicles

    Directory of Open Access Journals (Sweden)

    Elmira G. Sayfetdinova

    2017-03-01

    Full Text Available Objective: to identify the main reasons for the dynastic marriage between Mamluk Sultan al-Nasir and the Chinggisid princess Tulunbay and to analyze the impact of the termination of the marriage, according to medieval Arab chronicles. Research materials: medieval Arab chronicles of Mamluk authors: Ibn Duqmaq, al-Qalqashandi, al-Maqrizi, Mogultay, al-Nuwayri, Ibn Tagriberdi, al-Ayni et al. Results and novelty of the research: diplomatic relations between Egypt and the Golden Horde were the result of economic and foreign policy objectives of both states. Egypt at that time was one of the most powerful and influential states in the Muslim East, which showed an increased interest in events in the Golden Horde. This interest was stimulated by the fact that the Golden Horde was involved in the orbit of Islam and began to more intensively integrate Islam into the everyday culture of the Golden Horde society. After the Golden Horde had strengthened its position during the reign of khan Uzbek, Mamluk sultans began to consolidate even more their relations with the Golden Horde. One of the most important steps for the rapprochement between the two countries was a dynastic marriage between Mamluk Sultan al-Nasir and the Chinggisid princess Tulunbay. The object of this study is relevant, since the issue of political significance of dynastic relations between Mamluk and the Golden Horde rulers remain understudied. Meanwhile, the dynastic marriage is presented as a political act: as an expression of the good will of the state in relation to the other and a way to strengthen the influence of one country on another. The novelty of this research lies in the fact that, along with a detailed analysis of the Arab chronicles’ information on this subject, it presents for the first time the tomb of princess Tulunbay, which has been preserved in Egypt.

  5. Khajeh Nasir al-Din al-Tusi’s Role in the Interaction of Triple Paradigms of Islamic Philosophy

    Directory of Open Access Journals (Sweden)

    r Mohammadzadeh

    2013-08-01

    Full Text Available Our aim in this article is to investigate Khajeh Nasir`s effective role in emergence, growth and development of triple paradigms of Islamic philosophy, that are, Masha’, Ishraq and al-Hekmah al-Motealiyeh. Thus, first we present a summary of the meaning of “paradigm” and then discuss Tusi`s role in the development of triple paradigms of Islamic philosophy. We believe that, by using an interactive approach, Khajeh Nasir has attained a new approach to understand the paradigms. He is the first thinker in Islamic world who created a constructive and effective interaction between two paradigms of Masha’ and Ishraq, and paved the way for the emergence of al-Hekmah al-Motealiyeh. This can be explained with regard to either the conceptualization of al-Hekmat al-Motealiyeh or epistemological approach. Al-Hekmah Al-Motealiyah was influenced a lot by Tusi.

  6. Tilapia (Tilapiinae. Thematic bibliography

    Directory of Open Access Journals (Sweden)

    N. Kolesnyk

    2018-03-01

    Full Text Available Purpose. Forming a thematic bibliographic list of publications on certain issues of the biotechnics of the cultivation of tilapia (Tilapiinae in accordance with the specificity of aquaculture in the conditions of different types of fish farms of Europe, Asia, and Africa. Methodology. In the process of the preparation of the thematic list, both holistic and selective methods have been used. The bibliographic core was formed by Ukrainian, Russian and English literature sources from the stock of the scientific library of the Institute of Fisheries NAAS and scientific electronic library “CyberLeninka”. Findings. A thematic bibliographic list of major publication was formed: thematic collections of research papers, proceedings of international scientific and practical conferences, scientific works, articles and dissertation abstracts. It is composed of 202 sources, 85 of which are in English. The listed publications cover a time period from 1965 to 2017. However, the majority of them are after 1991. The scientific sources illustrate the studies on feeding, selective breeding, ecology, culture technologies and aquaculture-biological characteristics of the most widespread fish in world aquaculture – tilapia. The literary sources are arranged in alphabetical order by author or title, and described according to DSTU 8302:2015 “Information and documentation. Bibliographic reference. General principles and rules of composition”, with the amendments (code UKND 01.140.40, as well as in accordance with the requirements of APA style — international standard of references. Practical value. The list may be useful for scientists, practitioners, students, whose area of ​​interests covers the questions of the cultivation and study of the biological features of tilapia.

  7. Tilapia culture in Kuwait: constraints and solutions

    OpenAIRE

    Ridha, M.T.

    2006-01-01

    Tilapia farming in Kuwait is in its early stages. Slow growth, high production cost and poor demand are the major constraints to the expansion of tilapia culture in Kuwait. This article presents some suggestions for overcoming these problems to improve the economic feasibility of tilapia culture in Kuwait.

  8. Development of Streptococcus agalactiae vaccines for tilapia.

    Science.gov (United States)

    Liu, Guangjin; Zhu, Jielian; Chen, Kangming; Gao, Tingting; Yao, Huochun; Liu, Yongjie; Zhang, Wei; Lu, Chengping

    2016-12-21

    Vaccination is a widely accepted and effective method to prevent most pathogenic diseases in aquaculture. Various species of tilapia, especially Nile tilapia Oreochromis niloticus, are farmed worldwide because of their high consumer demand. Recently, the tilapia-breeding industry has been hampered by outbreaks of Streptococcus agalactiae infection, which cause high mortality and huge economic losses. Many researchers have attempted to develop effective S. agalactiae vaccines for tilapia. This review provides a summary of the different kinds of S. agalactiae vaccines for tilapia that have been developed recently. Among the various vaccine types, inactivated S. agalactiae vaccines showed superior protection efficiency when compared with live attenuated, recombinant and DNA vaccines. With respect to vaccination method, injecting the vaccine into tilapia provided the most effective immunoprotection. Freund's incomplete adjuvant appeared to be suitable for tilapia vaccines. Other factors, such as immunization duration and number, fish size and challenge dose, also influenced the vaccine efficacy.

  9. Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015-2016.

    Science.gov (United States)

    Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

    2017-06-01

    During 2015-2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

  10. Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015?2016

    OpenAIRE

    Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

    2017-01-01

    During 2015?2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

  11. SNP marker detection and genotyping in tilapia

    NARCIS (Netherlands)

    Bers, van N.E.M.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Dibbits, B.W.; Komen, J.

    2012-01-01

    We have generated a unique resource consisting of nearly 175 000 short contig sequences and 3569 SNP markers from the widely cultured GIFT (Genetically Improved Farmed Tilapia) strain of Nile tilapia (Oreochromis niloticus). In total, 384 SNPs were selected to monitor the wider applicability of the

  12. Modeling growth of specific spoilage organisms in tilapia ...

    African Journals Online (AJOL)

    Tilapia is an important aquatic fish, but severe spoilage of tilapia is most likely related to the global aquaculture. The spoilage is mostly caused by specific spoilage organisms (SSO). Therefore, it is very important to use microbial models to predict the growth of SSO in tilapia. This study firstly verified Pseudomonas and Vibrio ...

  13. Experimental infection of Tilapia Lake Virus (TiLV) in Nile tilapia (Oreochromis niloticus) and red tilapia (Oreochromis spp.).

    Science.gov (United States)

    Tattiyapong, Puntanat; Dachavichitlead, Worawan; Surachetpong, Win

    2017-08-01

    Since 2015, a novel orthomyxo-like virus, tilapia lake virus (TiLV) has been associated with outbreaks of disease and massive mortality of cultured Nile and red tilapia (Oreochromis niloticus and Oreochromis spp., respectively) in Thailand. In this study, TiLV was isolated from field samples and propagated in the permissive E-11 cell line, with cytopathic effect (CPE) development within 3-5days post-inoculation. Electron micrographs of infected E-11 cells and fish tissues confirmed the rounded, enveloped virions of 60 to 80nm with characteristics very similar to those of Orthomyxoviridae. In vivo challenge studies showed that high mortality in Nile (86%) and red tilapia (66%) occurred within 4-12days post-infection. The virus was re-isolated from challenged fish tissues in the permissive cell line, and PCR analysis confirmed TiLV as a causative pathogen. The distinct histopathology of challenged fish included massive degeneration and inflammatory cell infiltration in the liver and brain as well as the presence of eosinophilic intracytoplasmic inclusions in hepatocytes and splenic cells. Our results fulfilled Koch's postulates and confirmed that TiLV is an etiologic agent of mass mortality of tilapia in Thailand. The emergence of this virus in many countries has helped increase awareness that it is a potential threat to tilapia aquacultured in Thailand, Asia, and worldwide. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Observations on the helminth parasites of wild and cultured tilapia in ...

    African Journals Online (AJOL)

    A total of 449 specimen of Tilapia comprising Tilapia nilotica (Oreochromis), Tilapia zilli and Tilapia galilea (Sarotherodon) collected from the Federal and State Fish ponds, Okigwe and from the Imo River were examined for helminth infections. Out of these, only 5 (1.1%) fish were infected. These came from the wild. Tilapia ...

  15. Copy Number Variations in Tilapia Genomes.

    Science.gov (United States)

    Li, Bi Jun; Li, Hong Lian; Meng, Zining; Zhang, Yong; Lin, Haoran; Yue, Gen Hua; Xia, Jun Hong

    2017-02-01

    Discovering the nature and pattern of genome variation is fundamental in understanding phenotypic diversity among populations. Although several millions of single nucleotide polymorphisms (SNPs) have been discovered in tilapia, the genome-wide characterization of larger structural variants, such as copy number variation (CNV) regions has not been carried out yet. We conducted a genome-wide scan for CNVs in 47 individuals from three tilapia populations. Based on 254 Gb of high-quality paired-end sequencing reads, we identified 4642 distinct high-confidence CNVs. These CNVs account for 1.9% (12.411 Mb) of the used Nile tilapia reference genome. A total of 1100 predicted CNVs were found overlapping with exon regions of protein genes. Further association analysis based on linear model regression found 85 CNVs ranging between 300 and 27,000 base pairs significantly associated to population types (R 2  > 0.9 and P > 0.001). Our study sheds first insights on genome-wide CNVs in tilapia. These CNVs among and within tilapia populations may have functional effects on phenotypes and specific adaptation to particular environments.

  16. The Business Analysis of Tilapia and Tilapia Mixed Common Carp Floating Cages at Toba Lake in Kelurahan Haranggaol Haranggaol Horison Sub District Simalungun Regency Notrh Sumatera Utara

    OpenAIRE

    Hutagalung, Ningsih Agresia; ', Hendrik; ', Darwis

    2016-01-01

    This study was conducted on 26 January to February 9 2016 in the Kelurahan Haranggaol Haranggaol Horison sub district Simalungun regency north sumatera province. The purpose of the study was to determine and profit tilapia and tilapia mixed common carp and tilapia floating cage tilapia and business, know tilapia mixed common carp in floating cage in the review of several criteria investation like FRR, RCR, PPC. The method used in this research is a case study. Based on the results obtained by...

  17. Production of Genetically Improved Organic Nile Tilapia

    NARCIS (Netherlands)

    Charo, H.; Komen, J.; Bovenhuis, H.; Rezk, M.A.; Ponzoni, R.W.

    2008-01-01

    Demand for organic products for human consumption has been on the increase due to the belief that organic products are safer and healthier to the consumer and the environment. In developing countries, Nile tilapia (Oreochromis niloticus) is usually grown in low-input organically fed ponds with

  18. Mossambicus tilapia (Oreochromis mossambicus) collected from ...

    Indian Academy of Sciences (India)

    ... bla_{CTX-M} gene, which is a common ESBL gene in clinics. The studydemonstrates that tilapia found in the polluted waters can serve as reservoirs and an alternative route for human exposure toclinically important ARG-carrying bacteria. The consumption and handling of these fish may pose a potential health risk.

  19. Changes in haematological parameters of Tilapia guineensis ...

    African Journals Online (AJOL)

    Changes in haematological parameters of Tilapia guineensis exposed to different concentrations of detergent under laboratory conditions. ... The experiment evaluated sub-lethal effect of the exposure on some haematological parameters including haemoglobin (Hb), red blood cell (RBC), packed cell volume (PCV), white ...

  20. A review of piscine islet xenotransplantation using wild-type tilapia donors and the production of transgenic tilapia expressing a “humanized” tilapia insulin

    Science.gov (United States)

    Wright, James R; Yang, Hua; Hyrtsenko, Olga; Xu, Bao-You; Yu, Weiming; Pohajdak, Bill

    2014-01-01

    Most islet xenotransplantation laboratories have focused on porcine islets, which are both costly and difficult to isolate. Teleost (bony) fish, such as tilapia, possess macroscopically visible distinct islet organs called Brockmann bodies which can be inexpensively harvested. When transplanted into diabetic nude mice, tilapia islets maintain long-term normoglycemia and provide human-like glucose tolerance profiles. Like porcine islets, when transplanted into euthymic mice, they are rejected in a CD4 T-cell-dependent manner. However, unlike pigs, tilapia are so phylogenetically primitive that their cells do not express α(1,3)Gal and, because tilapia are highly evolved to live in warm stagnant waters nearly devoid of dissolved oxygen, their islet cells are exceedingly resistant to hypoxia, making them ideal for transplantation within encapsulation devices. Encapsulation, especially when combined with co-stimulatory blockade, markedly prolongs tilapia islet xenograft survival in small animal recipients, and a collaborator has shown function in diabetic cynomolgus monkeys. In anticipation of preclinical xenotransplantation studies, we have extensively characterized tilapia islets (morphology, embryologic development, cell biology, peptides, etc.) and their regulation of glucose homeostasis. Because tilapia insulin differs structurally from human insulin by 17 amino acids, we have produced transgenic tilapia whose islets stably express physiological levels of humanized insulin and have now bred these to homozygosity. These transgenic fish can serve as a platform for further development into a cell therapy product for diabetes. PMID:25040337

  1. A review of piscine islet xenotransplantation using wild-type tilapia donors and the production of transgenic tilapia expressing a "humanized" tilapia insulin.

    Science.gov (United States)

    Wright, James R; Yang, Hua; Hyrtsenko, Olga; Xu, Bao-You; Yu, Weiming; Pohajdak, Bill

    2014-01-01

    Most islet xenotransplantation laboratories have focused on porcine islets, which are both costly and difficult to isolate. Teleost (bony) fish, such as tilapia, possess macroscopically visible distinct islet organs called Brockmann bodies which can be inexpensively harvested. When transplanted into diabetic nude mice, tilapia islets maintain long-term normoglycemia and provide human-like glucose tolerance profiles. Like porcine islets, when transplanted into euthymic mice, they are rejected in a CD4 T-cell-dependent manner. However, unlike pigs, tilapia are so phylogenetically primitive that their cells do not express α(1,3)Gal and, because tilapia are highly evolved to live in warm stagnant waters nearly devoid of dissolved oxygen, their islet cells are exceedingly resistant to hypoxia, making them ideal for transplantation within encapsulation devices. Encapsulation, especially when combined with co-stimulatory blockade, markedly prolongs tilapia islet xenograft survival in small animal recipients, and a collaborator has shown function in diabetic cynomolgus monkeys. In anticipation of preclinical xenotransplantation studies, we have extensively characterized tilapia islets (morphology, embryologic development, cell biology, peptides, etc.) and their regulation of glucose homeostasis. Because tilapia insulin differs structurally from human insulin by 17 amino acids, we have produced transgenic tilapia whose islets stably express physiological levels of humanized insulin and have now bred these to homozygosity. These transgenic fish can serve as a platform for further development into a cell therapy product for diabetes. © 2014 The Authors. Xenotransplantation Published by John Wiley & Sons Ltd.

  2. Production of salinity tolerant Nile tilapia, Oreochromis niloticus ...

    African Journals Online (AJOL)

    Production of salinity tolerant Nile tilapia, Oreochromis niloticus through traditional and modern breeding methods: II. Application of genetically modified breeding by introducing foreign DNA into fish gonads.

  3. Business plan Tilapia cage farming in Tete Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Meer, van der Magnus; Brouwer, Herman

    2015-01-01

    Tete province offers great opportunities for cage farming of tilapia in Lake Cahora Bassa. The climate and water quality are favourable for fish production, and the fast economic developments in the region will facilitate fish sales. In Tete tilapia (pende) is highly valued food. Major markets for

  4. Monitoring of metals in Tilapia nilotica tissues, bottom sediments ...

    African Journals Online (AJOL)

    Tilapia (Tilapia nilotica), bottom sediments and water were collected from Nworie River and Oguta Lake. The muscle, liver and gills of the fish as well as the bottom sediments and water were analysed for Al, Cr, Cd, Pb, As, Zn, Mn, Co, Se, Cu, Ni and Fe using atomic absorption spectrophotometer to highlight the importance ...

  5. Growth comparison of Nile tilapia (Oreochromis niloticus) and Blue ...

    African Journals Online (AJOL)

    This study was conducted to compare and evaluate the productive performance characteristics of the base generation (F0) of Nile tilapia, Oreochromis niloticus and Blue tilapia, Oreochromis aureus under the effect of interspecific hybridization and genetically modified breeding by introducing a fragmented purified DNA ...

  6. Comparative analysis of the aquaculture potential of hybrid Tilapia ...

    African Journals Online (AJOL)

    , on the growth rate, feeding efficiency and mortality rates of hybrid tilapiaTilapia zillii (male) x T. guineensis (female) — was evaluated for 233 days. Fish of average weight 12.59g were stocked at a density of 20 fish m–³ and were fed a 30% ...

  7. Heritability of cold tolerance in Nile tilapia, Oreochromis niloticus, juveniles

    NARCIS (Netherlands)

    Charo-Karisa, H.; Rezk, M.A.; Bovenhuis, H.; Komen, J.

    2005-01-01

    The inability of tilapia to tolerate low temperatures is of major economic concern as it reduces their growing season and leads to over winter mortality. In this study, cold tolerance of juvenile Nile tilapia, Oreochromis niloticus, was investigated and heritability estimates obtained. A total of 80

  8. Prevalence and intensity of gill monogenean parasites of Tilapia ...

    African Journals Online (AJOL)

    ... C. arthracanthus, C. yanni, C. lagoonaris, C. louipaysani and C. kouassii based on the sex of Tilapia guineensis. This could enable the use of appropriate methods to fight against these pathogens, especially in intensive fish farming. Keywords: Monogeneans, Tilapia guineensis, population dynamics, Lake Ayamé 2.

  9. Signatures of selection in tilapia revealed by whole genome resequencing.

    Science.gov (United States)

    Xia, Jun Hong; Bai, Zhiyi; Meng, Zining; Zhang, Yong; Wang, Le; Liu, Feng; Jing, Wu; Wan, Zi Yi; Li, Jiale; Lin, Haoran; Yue, Gen Hua

    2015-09-16

    Natural selection and selective breeding for genetic improvement have left detectable signatures within the genome of a species. Identification of selection signatures is important in evolutionary biology and for detecting genes that facilitate to accelerate genetic improvement. However, selection signatures, including artificial selection and natural selection, have only been identified at the whole genome level in several genetically improved fish species. Tilapia is one of the most important genetically improved fish species in the world. Using next-generation sequencing, we sequenced the genomes of 47 tilapia individuals. We identified a total of 1.43 million high-quality SNPs and found that the LD block sizes ranged from 10-100 kb in tilapia. We detected over a hundred putative selective sweep regions in each line of tilapia. Most selection signatures were located in non-coding regions of the tilapia genome. The Wnt signaling, gonadotropin-releasing hormone receptor and integrin signaling pathways were under positive selection in all improved tilapia lines. Our study provides a genome-wide map of genetic variation and selection footprints in tilapia, which could be important for genetic studies and accelerating genetic improvement of tilapia.

  10. Parasitism affects vaccine efficacy against Streptococcus iniae in Nile tilapia

    Science.gov (United States)

    Tilapia culture worldwide is estimated to be US$ 5 billion and is important to domestic and global food security. Parasites and bacteria co-occur in both extensive and intensive production of tilapia. The effect of parasitism on vaccine performance in fish is little studied. The objective of this ...

  11. Screening and identification of a microsatellite marker associated with sex in Wami tilapia, Oreochromis urolepis hornorum.

    Science.gov (United States)

    Zhu, Huaping; Liu, Zhigang; Lu, Maixin; Gao, Fengying; Ke, Xiaoli; Ma, Dongmei; Huang, Zhanghan; Cao, Jianmeng; Wang, Miao

    2016-06-01

    In this study, primer pairs of 15 microsatellite markers associated with sex determination of tilapia were selected and amplified in Wami tilapia, Oreochromis urolepis hornorum. While one marker, UNH168, on linkage group 3 (LG3) was associated (P tilapia chromosome pair (chromosome 1, equivalent to LG3). This sex-linked microsatellite marker could potentially be used for marker-assisted selection in tilapia breeding programmes to produce monosex male tilapia.

  12. Mapping QTL for Omega-3 Content in Hybrid Saline Tilapia.

    Science.gov (United States)

    Lin, Grace; Wang, Le; Ngoh, Si Te; Ji, Lianghui; Orbán, Laszlo; Yue, Gen Hua

    2018-02-01

    Tilapia is one of most important foodfish species. The low omega-3 to omega-6 fatty acid ratio in freshwater tilapia meat is disadvantageous for human health. Increasing omega-3 content is an important task in breeding to increase the nutritional value of tilapia. However, conventional breeding to increase omega-3 content is difficult and slow. To accelerate the increase of omega-3 through marker-assisted selection (MAS), we conducted QTL mapping for fatty acid contents and profiles in a F 2 family of saline tilapia generated by crossing red tilapia and Mozambique tilapia. The total omega-3 content in F 2 hybrid tilapia was 2.5 ± 1.0 mg/g, higher than that (2.00 mg/g) in freshwater tilapia. Genotyping by sequencing (GBS) technology was used to discover and genotype SNP markers, and microsatellites were also genotyped. We constructed a linkage map with 784 markers (151 microsatellites and 633 SNPs). The linkage map was 2076.7 cM long and consisted of 22 linkage groups. Significant and suggestive QTL for total lipid content were mapped on six linkage groups (LG3, -4, -6, -8, -13, and -15) and explained 5.8-8.3% of the phenotypic variance. QTL for omega-3 fatty acids were located on four LGs (LG11, -18, -19, and -20) and explained 5.0 to 7.5% of the phenotypic variance. Our data suggest that the total lipid and omega-3 fatty acid content were determined by multiple genes in tilapia. The markers flanking the QTL for omega-3 fatty acids can be used in MAS to accelerate the genetic improvements of these traits in salt-tolerant tilapia.

  13. Technical evaluation of tilapia (Oreochromis niloticus) monoculture and tilapia-prawn (Macrobrachium rosenbergii) polyculture in earthen ponds with or without substrates for periphyton development

    NARCIS (Netherlands)

    Uddin, S.; Farzana, A.; Fatema, M.K.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.

    2007-01-01

    The effects of periphyton grown on bamboo substrate, on growth and production of Nile tilapia, Oreochromis niloticus (Genetically Improved Farmed Tilapia strain) in monoculture and polyculture with the freshwater prawn (Macrobrachium rosenbergii) were studied and economically evaluated. The

  14. Bioaccumulation factor for I-131 in aquatic biota II fish - tilapia (Tilapia Mossambica)

    International Nuclear Information System (INIS)

    Garcia, G.F.; Casyao, J.M.; Bautista, E.Rb.

    1982-01-01

    The study was undertaken to provide local values for an essential parameter in the estimation of the dose contribution of I-131 through ingestion of fresh water fish. The result showed that the tilapia used in the experiment did not vary significantly in weight and no definite conclusion can be derived as to the effect of body size to bioaccumulation of I-131. (ELC)

  15. Tilapia and human CLIC2 structures are highly conserved.

    Science.gov (United States)

    Zeng, Jiao; Li, Zhengjun; Lui, Eei Yin; Lam, Siew Hong; Swaminathan, Kunchithapadam

    2018-01-08

    Chloride intracellular channels (CLICs) exist in soluble and membrane bound forms. We have determined the crystal structure of soluble Clic2 from the euryhaline teleost fish Oreochromis mossambicus. Structural comparison of tilapia and human CLIC2 with other CLICs shows that these proteins are highly conserved. We have also compared the expression levels of clic2 in selected osmoregulatory organs of tilapia, acclimated to freshwater, seawater and hypersaline water. Structural conservation of vertebrate CLICs implies that they might play conserved roles. Also, tissue-specific responsiveness of clic2 suggests that it might be involved in iono-osmoregulation under extreme conditions in tilapia. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Sublethal effects of industrial chemicals on fish fingerlings (Tilapia ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-22

    Mar 22, 2010 ... Key words: Tilapia guineensis, industrial chemical, bioaccumulation, surfactants. ... product that has acceptable stability in oil pipelines. (Patton, 1995). .... assays were assessed with the two-factor ANOVA (analysis of.

  17. Sundried Cassava Leaf Meal as Protein Source for Nile Tilapia

    African Journals Online (AJOL)

    (Ng and Wee, 1989), low digestibility in Asian sea bass, Lates ... Source for Nile Tilapia Oreochromis niloticus (L) Juvenile's Diet. *Madalla1, N. ... growth, nutrient utilisation and whole body composition after an eight week growth trial. SGR.

  18. Bacteria Associated with Fresh Tilapia Fish (Oreochromis niloticus ...

    African Journals Online (AJOL)

    acer

    Keywords: Bacteria, Tilapia fish and Sokoto central market. INTRODUCTION ... The bacteria are transmitted by fish that have made contact ... with which a product spoils is also related to the .... Base on the percentage frequency of occurance ,.

  19. Morphological variation of Nile tilapia populations from major water ...

    African Journals Online (AJOL)

    ACSS

    tilapia (Oreochromis niloticus) stocks in lakes Albert, Edward and George, as well as in Albert Nile. River ... multivariate approaches including principal component analysis, ... Along the way, many private ... and selection for the best performing.

  20. Optimal feeding rate for Nile tilapia (Oreochromis niloticus)

    OpenAIRE

    Chowdhury, Dilip Kumar

    2011-01-01

    The aim of this study was to define optimal feeding rates for Nile tilapia (Oreochromis niloticus). Four experiments were carried out to evaluate the effect of feeding rate on growth performance of larger and juvenile tilapia by means of estimating growth rates, apparent nutrient digestibilities, feed utilization, body compositions, and nutrient and energy retentions. One nutritionally balanced diet (crude protein 342, crude fat 67, ash 47, starch 251 (all values in g (kg dry matter)-1)) was ...

  1. Tilapia lake virus (TiLV): Literature review

    OpenAIRE

    Jansen, Mona Dverdal; Mohan, Chadag Vishnumurthy

    2017-01-01

    Tilapia lake virus (TiLV) is an emerging infectious agent that has recently been identified in diseased tilapia on three continents. At the time of writing, scientific publications have reported TiLV in samples collected from Colombia, Ecuador, Egypt, Israel and Thailand. While the link between TiLV and disease outbreaks in Israel and Thailand are well documented, further investigations are being undertaken to determine the significance of TiLV in the other countries. Israel and Taiwan Provin...

  2. Adropin induction of lipoprotein lipase expression in tilapia hepatocytes.

    Science.gov (United States)

    Lian, Anji; Wu, Keqiang; Liu, Tianqiang; Jiang, Nan; Jiang, Quan

    2016-01-01

    The peptide hormone adropin plays a role in energy homeostasis. However, biological actions of adropin in non-mammalian species are still lacking. Using tilapia as a model, we examined the role of adropin in lipoprotein lipase (LPL) regulation in hepatocytes. To this end, the structural identity of tilapia adropin was established by 5'/3'-rapid amplification of cDNA ends (RACE). The transcripts of tilapia adropin were ubiquitously expressed in various tissues with the highest levels in the liver and hypothalamus. The prolonged fasting could elevate tilapia hepatic adropin gene expression, whereas no effect of fasting was observed on hypothalamic adropin gene levels. In primary cultures of tilapia hepatocytes, synthetic adropin was effective in stimulating LPL release, cellular LPL content, and total LPL production. The increase in LPL production also occurred with parallel rises in LPL gene levels. In parallel experiments, adropin could elevate cAMP production and up-regulate protein kinase A (PKA) and PKC activities. Using a pharmacological approach, cAMP/PKA and PLC/inositol trisphosphate (IP3)/PKC cascades were shown to be involved in adropin-stimulated LPL gene expression. Parallel inhibition of p38MAPK and Erk1/2, however, were not effective in these regards. Our findings provide, for the first time, evidence that adropin could stimulate LPL gene expression via direct actions in tilapia hepatocytes through the activation of multiple signaling mechanisms. © 2016 Society for Endocrinology.

  3. Adaptation, growth and survival of tilapia (Oreochromis niloticus) in Bafgh brackish water

    OpenAIRE

    Sarsangi, A.H.; Mohammadi, M.; Mashaii, N.; Rajabipou, F.; Bitaraf, A.; Askari, H.M.; Moazedi, J.; Nezamabadi, H.; Hosseinzadeh Sahafi, H.

    2012-01-01

    An experiment was conducted to evaluate the possibility of adaptation, growth and survival of Nile tilapia (Oreochromis niloticus) with 0.3g initial weight and red tilapia (Oreochromis sp.) with 0.7g initial weight in underground brackish water. Fry of Nile tilapia and red tilapia imported from Indonesia and after passing larviculture (25g) were examined separately in fiber glass tank by two replicate. Fish were fed at a restricted feeding program according to standard table during the light ...

  4. Complete mitochondrial DNA sequences of the Victoria tilapia (Oreochromis variabilis) and Redbelly Tilapia (Tilapia zilli): genome characterization and phylogeny analysis.

    Science.gov (United States)

    Kinaro, Zachary Omambia; Xue, Liangyi; Volatiana, Josies Ancella

    2016-07-01

    The Cichlid fishes have played an important role in evolutionary biology, population studies and aquaculture industry with East African species representing a model suited for studying adaptive radiation and speciation for cichlid genome projects in which closely related genomes are fast emerging presenting questions on phenotype-genotype relations. The complete mitochondrial genomes presented here are for two closely related but eco-morphologically distinct Lake Victoria basin cichlids, Oreochromis variabilis, an endangered native species and Tilapia zilli, an invasive species, both of which are important economic fishes in local areas. The complete mitochondrial genomes determined for O. variabilis and T. zilli are 16 626 and 16,619 bp, respectively. Both the mitogenomes contain 13 protein-coding genes, 22 tRNAs, 2 rRNAs and a non-coding control region, which are typical of vertebrate mitogenomes. Phylogenetic analyses of the two species revealed that though both lie within family Cichlidae, they are remotely related.

  5. Degree-days as a tool for use in producing tilapia fry for sex inversion

    Science.gov (United States)

    Hormonal sex inversion of newly hatched tilapia fry continues to be an important method to produce monosex male tilapia fingerlings. Large numbers of tilapia fry suitable for sex inversion can be produced by periodic complete harvest of earthen reproduction ponds. Traditionally, harvest interval was...

  6. Natural mating in Nile tilapia (Oreochromis niloticus L.) : implications for reproductive success, inbreeding and cannibalism

    NARCIS (Netherlands)

    Fessehaye, Y.

    2006-01-01

    Niletilapia ( Oreochromis niloticus L.) is one of the most important species among the commercially farmed tilapias. Both small-scale and commercial production of tilapia is rapidly expanding in many countries of the world because

  7. DNA replication and repair in Tilapia cells

    International Nuclear Information System (INIS)

    Yew, F.H.; Chang, L.M.

    1984-01-01

    The effect of ultraviolet radiation on a cell line established from the warm water fish Tilapia has been assessed by measuring the rate of DNA synthesis, excision repair, post-replication repair and cell survival. The cells tolerate ultraviolet radiation better than mammalian cells with respect to DNA synthesis, post-replication repair and cell survival. They are also efficient in excision repair, which in other fish cell lines has been found to be at a low level or absent. Their response to the inhibitors hydroxyurea and 1-β-D-arabinofuranosylcytosine is less sensitive than that of other cell lines, yet the cells seem to have very small pools of DNA precursor. (author)

  8. Inapparent Streptococcus agalactiae infection in adult/commercial tilapia.

    Science.gov (United States)

    Sun, Jiufeng; Fang, Wei; Ke, Bixia; He, Dongmei; Liang, Yuheng; Ning, Dan; Tan, Hailing; Peng, Hualin; Wang, Yunxin; Ma, Yazhou; Ke, Changwen; Deng, Xiaoling

    2016-05-24

    We report on inapparent infections in adult/commercial tilapia in major tilapia fish farms in Guangdong. A total of 146 suspected isolates were confirmed to be S. agalactiae using an API 20 Strep system and specific PCR amplification. All isolates were identified as serotype Ia using multiplex serotyping PCR. An MLST assay showed single alleles of adhP (10), atr (2), glcK (2), glnA (1), pheS (1), sdhA (3) and tkt (2), and this profile was designated 'unique ST 7'. The analysis of virulence genes resulted in 10 clusters, of which dltr-bca-sodA-spb1-cfb-bac (62, 42.47%) was the predominant virulence gene profile. The PFGE analysis of S. agalactiae yielded 6 distinct PFGE types (A, B, C, D, F and G), of which Pattern C (103) was the predominant type, accounting for approximately 70.55% (103/146) of the total S. agalactiae strains. Therefore, unlike what has been found in juvenile tilapia, in which PFGE pattern D/F is the major prevalent pattern, we found that pattern C was the major prevalent pattern in inapparent infected adult/commercial tilapia in Guangdong, China. In conclusion, we close a gap in the current understanding of S. agalactiae epidemiology and propose that researchers should be alert for inapparent S. agalactiae infections in adult/commercial tilapia to prevent a potential threat to food safety.

  9. Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China

    DEFF Research Database (Denmark)

    Li, Kang; Clausen, Jesper Hedegaard; Murrell, Kenneth Darwin

    2013-01-01

    Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia...... aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1...... for tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level....

  10. The radiosensitivity of nile tilapia (Oreochromis niloticus) fingerlings

    International Nuclear Information System (INIS)

    Reyes, Michael Joseph T.; Velasco, Pia Victoria V.

    2000-04-01

    The nile tilapia (Oreochromis niloticus), a very popular fish commercially in the Philippines, was studied to determine its radiosensitivity and to see its potential as a biological indicator in aquatic ecosystems. Nile tilapia was seen to be radiosensitive. The fish were exposed to gamma-irradiation and chromosomal aberrations were induced. The various types of aberrations seen were chromatid gaps, chromosome gaps, chromatid fragments, dicentric rings, fusions, despiralizations and translocations. Among the aberrations observed, dicentric rings, fusions and chromosome gaps were strongly correlated with dosage, with only the dicentric rings increasing steadily with increasing dosage. In the course of the study, the lethal dosage 50 for nile tilapia with 18 days was determined and it was observed at 2.0 krad. The modal chromosome number was also established at 2n=44 with a karyotype exhibiting 22 pairs of acrocentric chromosomes with 2 pairs of marker chromosomes present. (Author)

  11. The radiosensitivity of nile tilapia (Oreochromis niloticus) fingerlings

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, Michael Joseph T; Velasco, Pia Victoria V

    2000-04-01

    The nile tilapia (Oreochromis niloticus), a very popular fish commercially in the Philippines, was studied to determine its radiosensitivity and to see its potential as a biological indicator in aquatic ecosystems. Nile tilapia was seen to be radiosensitive. The fish were exposed to gamma-irradiation and chromosomal aberrations were induced. The various types of aberrations seen were chromatid gaps, chromosome gaps, chromatid fragments, dicentric rings, fusions, despiralizations and translocations. Among the aberrations observed, dicentric rings, fusions and chromosome gaps were strongly correlated with dosage, with only the dicentric rings increasing steadily with increasing dosage. In the course of the study, the lethal dosage{sub 50} for nile tilapia with 18 days was determined and it was observed at 2.0 krad. The modal chromosome number was also established at 2n=44 with a karyotype exhibiting 22 pairs of acrocentric chromosomes with 2 pairs of marker chromosomes present. (Author)

  12. Bioaccumulation factor of tritium in oyster and tilapia

    International Nuclear Information System (INIS)

    Garcia, T.Y.; Juan, N.B.

    1984-01-01

    This paper reports on the bioaccumulation factor as well as the residence time of tritium in marine organisms such as tilapia fish (Tilapia mossambica) and oyster (Crassostrea iredalei) reared under laboratory conditions. The organisms were submerged in aquarium water containing tritium with specific activity of 1.0 nCi/ml. The samples were analyzed for tissue-free water tritium (TFWT) by freeze drying and for tissue-bound tritium (TBT) by combustion methods. Tritiated water collected was assayed using the liquid scintillation counting technique. (author)

  13. Growth performance and feed utilization of Tilapia zillii (Gervais ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... Accepted 22 May, 2009. The aim of this study was to investigate the growth performance, feed utilization and body composition of Tilapia zillii fed diets where poultry by-product meal replaced fish meal protein at 0, 50 and 100% ... fish diets because of its high protein quality and palata- bility. However, fish ...

  14. Morphological variation of Nile tilapia populations from major water ...

    African Journals Online (AJOL)

    ... by hatchery operators throughout the country and in the East African region. ... there was high morphological variation among the different populations of Nile tilapia ... Most of the variation (86.97%) was associated with the fish body size, the ...

  15. Novel polymorphic microsatellites from Florida red tilapia and cross ...

    Indian Academy of Sciences (India)

    tems, Foster City, USA), M13 and M13R primers with the sequencer AB13730xl. Sequences were aligned using. Sequencher (GeneCodes, Ann Arbor, USA). Primers were designed for each microsatellite. One primer of each pair was labelled with either a 6FAM or a HEX fluorescent dye. Twenty Nile tilapia, 20 Mozambique ...

  16. Estimation of water pollution by genetic biomarkers in tilapia and ...

    African Journals Online (AJOL)

    This study was aimed at the estimation of water pollution with heavy metals using four biomarkers as well as to study the species-site interaction. Two species of tilapia as well as two catfish species caught from four sites that represent differential environmental stresses were used for this purpose. Water samples and gills ...

  17. Stomach Length and Food Preference of three Tilapia species ...

    African Journals Online (AJOL)

    Results showed that T . zillii was herbivorous while T . mariae and O. niloticus subsisted mainly on a wide variety of plankton. Generally, considerable quantities of zoo – and phyto-plankton were present in the food of the three species. Variations were observed in the gut lengths and dental anatomy of the tilapias which ...

  18. Growth comparison of Nile tilapia (Oreochromis niloticus) and Blue ...

    African Journals Online (AJOL)

    Administrator

    2011-09-26

    Sep 26, 2011 ... worm water food fish and exceeding the harvest of. Atlantic salmon ... transgenic fish, in theory, is not different from the natural processes, but it is a ..... delivered from fast growing genetically-modified Tilapia zillii: A productive ...

  19. Breeding for improved production of Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    Rutten, M.J.M.

    2005-01-01

    The aim of this thesis was to generate knowledge that supports the design of breeding programs for Nile tilapia targeting genetic improvement of body weight and fillet yield to serve the European market. To this end, both the genetic variation and the performance levels of different strains of

  20. Feeding selectivity of wild and pond-cultured Nile tilapia ...

    African Journals Online (AJOL)

    A comparison of feeding selectivity of wild and pond-cultured Nile tilapia Oreochromis niloticus was conducted in 2008. Water and fish samples were collected in Shirati Bay, Lake Victoria, and from fish ponds in Tarime district using a La Motte water sampler and seine nets, respectively. Cyanophytes were abundant and ...

  1. Nutritional evaluation of fermented palm kernel cake using red tilapia

    African Journals Online (AJOL)

    The use of palm kernel cake (PKC) and other plant residues in fish feeding especially under extensive aquaculture have been in practice for a long time. On the other hand, the use of microbial-based feedstuff is increasing. In this study, the performance of red tilapia raised on Trichoderma longibrachiatum fermented PKC ...

  2. Identification of Oreochromis niloticus (Linnaeus, 1758) and Tilapia ...

    African Journals Online (AJOL)

    Isoelectric focusing methodology using LKB 2117 Multiphor 11 electrofocusing apparatus was used for electofocusing and identification of Oreochromis niloticus and Tilapia zilli. The electrographs of the two species suggest clear protein differences producing species specific patterns. There were variations in the protein ...

  3. The antisickling effects of dried fish (tilapia) And dried prawn ...

    African Journals Online (AJOL)

    The antisickling effect of dried fish (Tilapia) and dried prawn (Astacus red) were investigated to ascertain the ability of the extracts of these samples to inhibit polymerisation of sickle cell haemoglobin (HbS), improve the Fe 2+/Fe 3+ ratio and lower the activity of lactate dehydrogenase (LDH) in blood plasma. The samples ...

  4. Optimum dietary protein requirement of genetically male tilapia ...

    African Journals Online (AJOL)

    The study was conducted to investigate the optimum dietary protein level needed for growing genetically male tilapia, Oreochromis niloticus. Diets containing crude protein levels 40, 42.5, 45, 47.5 and 50% were formulated and tried in triplicates. Test diets were fed to 20 fish/1m3 floating hapa at 5% of fish body weight daily ...

  5. Impacts of parasite infection on columnaris disease of tilapia

    Science.gov (United States)

    There is no information available on whether parasite infection will increase the susceptibility of tilapia to Flavobacterium columnare and whether parasite treatment could improve fish survival after F. columnare exposure. Two trials were conducted to evaluate 1) the susceptibility of hybrid tilapi...

  6. Pen Culture of the Black-Chinned Tilapia, Sarotherodon ...

    African Journals Online (AJOL)

    Pen-fish-culture as a culture-based fisheries approach was investigated in the Aglor Lagoon from December 2003 to June, 2004. The fish used in the study was the Black-chinned tilapia Sarotherodon melanotheron. The growth performance of S. melanotheron cultured for six months in the Aglor Lagoon under three ...

  7. Masculinization of Nile tilapia (Oreochromis niloticus) by immersion in androgens

    Science.gov (United States)

    Gale, W.L.; Fitzpatrick, M.S.; Lucero, M.; Contreras-Sanchez, W.M.; Schreck, C. B.

    1999-01-01

    The use of all-male populations increases the efficiency and feasibility of tilapia aquaculture. The objective of this study was to determine the efficacy of a short-term immersion procedure for masculinizing Nile tilapia (Oreochromis niloticus). Two synthetic androgens were evaluated: 17α-methyldihydrotestosterone (MDHT) and 17α-methyltestosterone (MT). Exposure (3 h) on 10 and again on 13 days post-fertilization to MDHT at 500 μg/1 successfully masculinized fry in all experiments, resulting in 100, 94 and 83 ± 2% males in Experiments 1, 2 and 3, respectively. Immersions in MDHT or MT at 100 μg/1 resulted in significantly skewed sex ratios in Experiments 1 and 3 (MT resulted in 73 and 83 ± 3% males; and MDHT resulted in 72 and 91 ± 1% males) but not in Experiment 2. Immersion in MT at 500 μg/1 only caused masculinization in Experiment 3. Although further research and refinement is needed, immersion of Nile tilapia in MDHT may provide a practical alternative to the use of steroid-treated feed. Furthermore, when compared with current techniques for steroid-induced sex inversion of tilapia, short-term immersion reduces the period of time that workers are exposed to anabolic steroids.

  8. Histological Changes of Liver in Overfed Young Nile Tilapia

    NARCIS (Netherlands)

    Taddesse, F.; Huh, M.D.; Bai, S.C.; Vijverberg, J.

    2014-01-01

    We investigated histopathologically liver structural responses of Nile Tilapia Oreochromis niloticus towards overfeeding. Mixed population of O. niloticus with mean weight of 55±3.83 g was acclimated for one week. Then, the fish were separated into control and treatment groups. Glass aquariums with

  9. Optimisation of selective breeding program for Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Trong, T.Q.

    2013-01-01

    The aim of this thesis was to optimise the selective breeding program for Nile tilapia in the Mekong Delta region of Vietnam. Two breeding schemes, the “classic” BLUP scheme following the GIFT method (with pair mating) and a rotational mating scheme with own performance selection and

  10. Comparison of bacterial communities of tilapia fish from Cameroon ...

    African Journals Online (AJOL)

    Comparison of bacterial communities of tilapia fish from Cameroon and Vietnam using PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis) ... The different PCR-DGGE 16S rDNA banding profiles obtained were analysed and results showed that there were specific bands for each geographical ...

  11. Business plan Tilapia Pond Farming in the Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Brouwer, Herman; Meer, van der Magnus

    2015-01-01

    This business plan has been prepared for local entrepreneurs who would like to expand their business portfolio or to start a value chain business in the aquaculture sector in the Zambezi Valley, Mozambique.

    Freshwater aquaculture in Mozambique consists mainly of small-scale tilapia

  12. Growth Performance, Yields and Economic Benefits of Nile Tilapia ...

    African Journals Online (AJOL)

    fish culture integration in the growth, yields and economic benefits of fish and vegetables. Two 200 m2 earthen fishponds were stocked with Nile tilapia Oreochromis niloticus at 20,000 fish fingerlings per hectare. Pond A was fertilized with ...

  13. Environmental color affects Nile tilapia reproduction

    Directory of Open Access Journals (Sweden)

    Volpato G.L.

    2004-01-01

    Full Text Available We investigated the effects of environmental color on the reproductive behavior of Nile tilapia, Oreochromis niloticus. Two environmental colors were tested by covering the aquarium (60 x 60 x 40 cm with white (12 groups or blue (13 groups cellophane and observing reproductive behavior in groups of 2 males (10.27 ± 0.45 cm and 3 females (10.78 ± 0.45 cm each. After assignment to the respective environmental color (similar luminosity = 100 to 120 Lux, the animals were observed until reproduction (identified by eggs in the female's mouth or up to 10 days after the first nest building. Photoperiod was from 6:00 h to 18:00 h every day. Food was offered in excess once a day and water quality was similar among aquaria. Daily observations were made at 8:00, 11:00, 14:00 and 17:00 h regarding: a latency to the first nest, b number of nests, c gravel weight removed (the male excavates the nest in the bottom of the aquarium, d nest area, and e mouthbrooding incubation (indication of reproduction. The proportion of reproducing fish was significantly higher (6 of 13 in the group exposed to the blue color compared the group exposed to the white color (1 of 12; Goodman's test of proportions. Moreover, males under blue light removed significantly larger masses of gravel (blue = 310.70 ± 343.50 g > white = 130.38 ± 102.70 g; P = 0.01 and constructed wider nests (blue = 207.93 ± 207.80 cm² > white = 97.68 ± 70.64 cm²; P = 0.03 than the control (white. The other parameters did not differ significantly between light conditions. We concluded that reproduction in the presence of blue light was more frequent and intense than in the presence of white light.

  14. Does feeding frequency affect utilization of added amino acids in Nile tilapia?

    OpenAIRE

    Hoque, Rezaul; Bajgai, Biswas

    2014-01-01

    Nile tilapia (Oreochromis niloticus) is one of the major farmed fish species, with main production in Asia, South and Central America that can tolerate a wide range of environmental stress and easily adapt with low quality of feed ingredients. The aims of the experiments were to determine effects of feeding frequency on utilization of protein and energy in Nile tilapia, to quantify differences in excretion of ammonia and ammonium in Nile tilapia fed the same daily ration, distributed over 2 a...

  15. MERCURY (Hg CONTENT OF MEAT TILAPIA FISH (Oreochromis niloticus WERE CULTIVATED IN PALANGKA RAYA CITY

    Directory of Open Access Journals (Sweden)

    Ciptadi

    2015-11-01

    Full Text Available Tilapia fish as Palangkarayan food are mostly cultivated in the river which exposed by mercury. To get information whether the fish have been contaminated by mercury, the mercury determination of tilapia fish meat cultivated in Kahayan river was carried out. The fish were analyzed based on age and the cultivation environment that are fishes cages in Kahayan river and isolated pond from streams of Kahayan river are also studied. The concentration of mercury in the flesh of tilapia with 5-7 months, kept in cages used to identify the content of mercury in fish tilapia cages in Kahayan river. The concentration of mercury in the flesh of tilapia reared in ponds aims to compare the mercury content in the tilapia in ponds the same age were used as comparison. The level of mercury in the samples was measured using a Mercury Analyzer. Data concentration of mercury in the flesh of tilapia were analyzed using analysis of variance (ANOVA: single factor with a significance level (α of 5%. The results showed that tilapia fish meat from the cages in the Kahayan river with age of 5-7 months contain mercury as much as 0.0145 ± 0.0005 ppm to 0.017 ± 0.001 ppm, which were lower than the maximum limit of mercury contamination in fish and processed products regulated by ISO 7387 in 2009 of 0.5 ppm. The the analysis of variance showed that the mercury content in tilapia fish meat was different by age and place of cultivation. The content of mercury in the tilapia fish meat increase with the increase of their age. The mercury content in tilapia fish cultivated in the isolated pond lower than that of in the tilapia fish meat cultivated in cages of 0.0115 ± 0.0005 ppm

  16. Molecular characterization and functional analysis of IRF3 in tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Gu, Yi-Feng; Wei, Qun; Tang, Shou-Jie; Chen, Xiao-Wu; Zhao, Jin-Liang

    2016-02-01

    Interferon regulatory factor 3 (IRF3) plays a key role in interferon (IFN) response and binding to the IFN stimulatory response elements (ISREs) within the promoter of IFN and IFN-stimulated genes followed by virus infection. In the current study, we discovered one IRF3 homologue in tilapia genome and analyzed the characterizations and functions of tilapia IRF3. Tilapia IRF3 contains 1368 bp with an ORF of 455 aa. Structurally, tilapia IRF3 protein typically shares the conserved characterizations with other species' IRF3 homologues, displaying conserved DNA-binding domain, IRF association domain, serine-rich C terminal domain, and tryptophan residue cluster. Phylogenetic analysis illustrated that tilapia IRF3 belongs to the IRF3 subfamily. Real-time PCR revealed a broad expression pattern of tilapia IRF3 in various tissues. Subcellular localization analysis showed that tilapia IRF3 mainly resides in the cytoplasm, Western blot demonstrated that IRF3 was distributed in the cytoplasmic fraction. Functionally, IRF3 was found to be transcriptionally up-regulated by the poly I:C stimulation. Moreover, reporter assay elucidated that tilapia IRF3 serves as a regulator in mediating IFN response by increasing the activity of IFN-β and ISRE-containing promoter. These data supported the view that tilapia IRF3 is a potential molecule in IFN immune defense system against viral infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The culture of Tilapia species in tropical and subtropical conditions

    Directory of Open Access Journals (Sweden)

    De Maeseneer, J.

    1984-01-01

    Full Text Available Although since long known by African fishermen it is only in the last 40 years that Tilapia has been recognized as one of the most promising groups of fish species for culture. The initial successes for culture in Central Africa were followed by several failures mainly because of excessive breeding and early sexual maturity in shallow waterbodies as ponds. From the present knowledge it appears that tilapia has a great future for increasing the productivity in unmanaged environments as man-made lakes and reservoirs primarily destined for the production of hydro-electricity. Careful stocking of paddies and irrigation canals can solve a number of biological problems associated with them and provide an additional though valuable high-protein food source. Great future offers also the culture of tilapia in traditional pond culture especially in polyculture with members of the carp family, mullets and waterfowl in areas of the tropical and subtropical belt. In coastal ponds T, mossambica is a valuable species for sanitary reasons. The culture of tilapia in small farm ponds often meets with failure owing to excessive breeding and stunting unless the all-male technique can be applied through government input and encouragement. As a rule this type of production will be the least attractive. Although Tilapia spp. do not achieve the largest individu al growth their tolerance towards adverse conditions and their acceptance of a wide variety of foodstuffs, primarily waste products from agriculture, their resistance to diseases and (at least in some species their tolerance of crowded environments make them suitable subject for cultures in raceways, circular tanks and cages. Through heavy inputs of water and pelletized feeds nearly incredible annual yields as 2 000 tonnes per ha of water surface (1 and more were realized. This means that this type of production surpasses by far any other known form of animal husbandry but it needs high technological input (thus

  18. Effectiveness of Aquaflor (50% florfenicol) administered in feed to control mortality associated with Streptococcus iniae in tilapia at a commercial tilapia production facility

    Science.gov (United States)

    Gaikowski, Mark P.; Schleis, Susan M.; Leis, Eric; Lasee, Becky A.; Endris, Richard G.

    2014-01-01

    The efficacy of Aquaflor (florfenicol; FFC) to control mortality caused by Streptococcus iniae in tilapia was evaluated under field conditions. The trial was initiated following presumptive diagnosis of S. iniae infection in a mixed group of fingerling (mean, 4.5 g) Nile Tilapia Oreochromis niloticus and a hybrid of Nile Tilapia×Blue Tilapia O. aureus. Diagnoses included mortality in source tank; examination of clinical signs and presence or absence of gram-positive cocci in brain, and collection of samples for microbiological review and disease confirmation of 60 moribund fish. Following presumptive diagnosis, tilapia (83/tank) were randomly transferred to each of 20 test tanks receiving the same water as the source tank (test tank water was not reused). Tilapia were offered either nonmedicated control feed or FFC-medicated feed (FFC at 15 mg/kg body weight/d; 10 tanks per regimen) for 10 consecutive days followed by a 14-d observation period during which only the nonmedicated control feed was offered. Streptococcus iniae was presumptively identified during pretreatment necropsy and confirmed by polymerase chain reaction assay; S. iniae was confirmed in samples taken during the dosing period but was not detected during the postdosing period. The FFC disk diffusion zone of inhibition ranged from 29 to 32 mm, while the minimum inhibitory concentration of FFC ranged from 2 to 4 μg/mL for the S. iniae isolates collected. Survival of tilapia assigned to the FFC-dose group was significantly greater at 14 d posttreatment than that of the nonmedicated controls. The odds of tilapia assigned to the FFC-dose group surviving to the end of the postdosing period were 1.34 times the odds of survival of tilapia assigned to the nonmedicated control group. There were no clinically apparent adverse effects associated with the administration of FFC-medicated feed in this study.

  19. Acute toxicity of ammonia to blue tilapia, Oreochromis aureus in ...

    African Journals Online (AJOL)

    The acute toxicity of blue tilapia, Oreochromis aureus (3.28 ± 0.36 g in body weight, 61.84 ± 2.08 mm in body length) exposed to environmental un-ionized ammonia at different salinities (1, 8, 12, 16 and 20 ppt) was assessed via a series of static exposure trials. Median lethal concentrations of 24 h of exposure were ...

  20. Identification of a Novel RNA Virus Lethal to Tilapia

    Science.gov (United States)

    Eyngor, Marina; Zamostiano, Rachel; Kembou Tsofack, Japhette Esther; Berkowitz, Asaf; Bercovier, Hillel; Tinman, Simon; Lev, Menachem; Hurvitz, Avshalom; Galeotti, Marco; Eldar, Avi

    2014-01-01

    Tilapines are important for the sustainability of ecological systems and serve as the second most important group of farmed fish worldwide. Significant mortality of wild and cultured tilapia has been observed recently in Israel. The etiological agent of this disease, a novel RNA virus, is described here, and procedures allowing its isolation and detection are revealed. The virus, denominated tilapia lake virus (TiLV), was propagated in primary tilapia brain cells or in an E-11 cell line, and it induced a cytopathic effect at 5 to 10 days postinfection. Electron microscopy revealed enveloped icosahedral particles of 55 to 75 nm. Low-passage TiLV, injected intraperitoneally in tilapia, induced a disease resembling the natural disease, which typically presents with lethargy, ocular alterations, and skin erosions, with >80% mortality. Histological changes included congestion of the internal organs (kidneys and brain) with foci of gliosis and perivascular cuffing of lymphocytes in the brain cortex; ocular inflammation included endophthalmitis and cataractous changes of the lens. The cohabitation of healthy and diseased fish demonstrated that the disease is contagious and that mortalities (80 to 100%) occur within a few days. Fish surviving the initial mortality were immune to further TiLV infections, suggesting the mounting of a protective immune response. Screening cDNA libraries identified a TiLV-specific sequence, allowing the design of a PCR-based diagnostic test. This test enables the specific identification of TiLV in tilapines and should help control the spread of this virus worldwide. PMID:25232154

  1. DNA fingerprinting of salinity resistance of full-sib Nile tilapia, Blue ...

    African Journals Online (AJOL)

    ******

    2012-05-01

    May 1, 2012 ... The same previous spawners of Nile tilapia, O. niloticus and Blue tilapia, O. aureus were used for full-sib of each of diallel interspecific hybridization fry production of ♀O. aureus x ♂ O. niloticus and ♀O. niloticus x ♂O. aureus. Water temperature was thermostatiscally regulated and fixed at 28°C.

  2. Quality Index Method developed for gutted and ungutted red tilapia (Oreochromis ssp

    Directory of Open Access Journals (Sweden)

    Nelson Gutiérrez G.

    2015-01-01

    Full Text Available Objective. To develop a Quality Index Method (QIM for gutted and ungutted red tilapia from aquaculture ponds. Materials and methods. 40 specimens of gutted red tilapia and 40 ungutted ones were located in foam polyethylene boxes within layers of ice and storage at 4°C. Three fish were randomly sampled on days 0, 3, 5, 8, 11, 14 and 17 for gutted tilapia, and on days 0, 3, 6, 9, 11, 14 and 16 for ungutted tilapia. A sensorial panel of 8 experts was formed to evaluate the product. With three samples each day with average points of the sensorial attributes proposed in the method, the quality index for gutted and ungutted red tilapia was obtained based on the storage time on ice. Results. The Quality Index Method obtained for gutted and ungutted red tilapia showed maximum values of 21 and 29, respectively. It was adjusted in an increasing lineal model with high correlation between the Quality Index and the storage time on ice. Conclusions. The developed model is useful to determine deterioration levels and to define storage and consumption time. For gutted red tilapia the panel rejected the fish after 8 - 11 days of storage whereas the ungutted red tilapia was rejected after 6 - 9 days.

  3. Nutritional Profile and Chemical Stability of Pasta Fortified with Tilapia (Oreochromis niloticus) Flour.

    Science.gov (United States)

    Monteiro, Maria Lúcia G; Mársico, Eliane T; Soares, Manoel S; Magalhães, Amanda O; Canto, Anna Carolina V C S; Costa-Lima, Bruno R C; Alvares, Thiago S; Conte, Carlos A

    2016-01-01

    Physicochemical parameters of pasta enriched with tilapia (Oreochromis niloticus) flour were investigated. Five formulations were prepared with different concentrations of tilapia flour as partial substitute of wheat flour: pasta without tilapia flour (PTF0%), pasta with 6% (PTF6%), 12% (PTF12%), 17% (PTF17%), and 23% (PTF23%) of tilapia flour. The formulations were assessed for proximate composition, fatty acid and amino acid profile on day 1 whereas, instrumental color parameters (L*, a* and b* values), pH, water activity (aw), and lipid and protein oxidation were evaluated on days 1, 7, 14, and 21 of storage at 25°C. Fortification with tilapia flour increased (p pasta with tilapia flour decreased (p pasta containing 12%, 17%, and 23% of tilapia flour than their counterparts, and the storage promoted an increase (p pasta with 6% of tilapia flour has the potential to be a technological alternative to food industry for the nutritional enrichment of traditional pasta with negligible negative effects on the chemical stability of the final product during 21 days at 25°C.

  4. Modelling of fillet traits based on body measurements in three Nile tilapia strains (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    Rutten, M.J.M.; Bovenhuis, H.; Komen, J.

    2004-01-01

    In Nile tilapia, breeding programs focus mainly on growth, and information on genetic improvement of fillet yield is scarce. In this study, slaughter data were collected on 1215 tilapia and used to analyze the relationship between body measurements and fillet weight and fillet yield. Fish were

  5. Trophic transfer of cadmium from duckweed (Lemna Minor L.) to Tilapia (Oreochromis mossambicus)

    NARCIS (Netherlands)

    Xue, Yan; Peijnenburg, Willie J G M; Huang, Jin; Wang, Dengjun; Jin, Yan

    2018-01-01

    The transfer of the toxic heavy metal Cd from duckweed (Lemna minor L.) to the freshwater fish tilapia (Oreochromis mossambicus) was investigated. Concentrations of Cd in different chemical forms in duckweed and in different tissues (gut, edible muscle, and remnants) of tilapia, i.e.,

  6. Characterization of a Novel Orthomyxo-like Virus Causing Mass Die-Offs of Tilapia.

    Science.gov (United States)

    Bacharach, Eran; Mishra, Nischay; Briese, Thomas; Zody, Michael C; Kembou Tsofack, Japhette Esther; Zamostiano, Rachel; Berkowitz, Asaf; Ng, James; Nitido, Adam; Corvelo, André; Toussaint, Nora C; Abel Nielsen, Sandra Cathrine; Hornig, Mady; Del Pozo, Jorge; Bloom, Toby; Ferguson, Hugh; Eldar, Avi; Lipkin, W Ian

    2016-04-05

    Tilapia are an important global food source due to their omnivorous diet, tolerance for high-density aquaculture, and relative disease resistance. Since 2009, tilapia aquaculture has been threatened by mass die-offs in farmed fish in Israel and Ecuador. Here we report evidence implicating a novel orthomyxo-like virus in these outbreaks. The tilapia lake virus (TiLV) has a 10-segment, negative-sense RNA genome. The largest segment, segment 1, contains an open reading frame with weak sequence homology to the influenza C virus PB1 subunit. The other nine segments showed no homology to other viruses but have conserved, complementary sequences at their 5' and 3' termini, consistent with the genome organization found in other orthomyxoviruses. In situ hybridization indicates TiLV replication and transcription at sites of pathology in the liver and central nervous system of tilapia with disease. The economic impact of worldwide trade in tilapia is estimated at $7.5 billion U.S. dollars (USD) annually. The infectious agent implicated in mass tilapia die-offs in two continents poses a threat to the global tilapia industry, which not only provides inexpensive dietary protein but also is a major employer in the developing world. Here we report characterization of the causative agent as a novel orthomyxo-like virus, tilapia lake virus (TiLV). We also describe complete genomic and protein sequences that will facilitate TiLV detection and containment and enable vaccine development. Copyright © 2016 Bacharach et al.

  7. Controlled laboratory challenge demonstrates substantial additive genetic variation in resistance to Streptococcus iniae in Nile tilapia

    Science.gov (United States)

    Streptococcus iniae is an etiologic agent of streptococcal disease in tilapia and is one of several Streptococcus spp. that negatively impact worldwide tilapia production. Methods for the prevention and control of S. iniae include vaccines, management strategies, and antibiotics. An alternative and ...

  8. Primer prueba de desafio controlado en tilapia del Nilo Para Resistencia a Streptococcus iniae

    Science.gov (United States)

    Intensification of tilapia production has resulted in disease outbreaks that negatively affect commercial fish farmers. One bacterial pathogen that commonly causes losses in tilapia production is Streptococcus iniae. Control and prevention of S. iniae can be difficult and requires an integrated fish...

  9. Spring forward with improved Nile tilapia Oreochromis niloticus resistant to Streptococcus iniae and Streptococcus agalactiae IB

    Science.gov (United States)

    Tilapia aquaculture worldwide is valued around US $ 7 billion. Tilapia are an important source of protein for domestic (top 5 most consumed seafoods) and global food security. Two gram postitive bacteria, Streptococcus iniae and S. agalactiae, are responsible for billion dollar losses annually. Gen...

  10. Agroindustrial byproducts in diets for Nile tilapia juveniles

    Directory of Open Access Journals (Sweden)

    João Sérgio Oliveira Carvalho

    2012-03-01

    Full Text Available This study was conducted to evaluate performance and body composition of tilapia (Oreochromis niloticus fed diets containing byproducts aerial parts of cassava meal (Manihot esculenta, mesquite pod meal (Prosopis juliflora, cocoa meal (Theobroma cacao and palm kernel cake (Elaeis guineensis and to analyze the economic viability of the feed. A total of 1,350 juvenile males (100 g were distributed in 15 cages (1 m³ in completely randomized design with five treatments (basal diet and four test diets and three replicates. The following aspects were evaluated: final weight, total feed intake, total weight gain, feed conversion, specific growth rate, protein efficiency ratio and survival rate, dry matter, crude protein, fat and ash body, the average cost of feed per kilogram of weight gain and economic efficiency rate. No differences were observed for total consumption of food or survival rate. For other variables, the inclusion of cocoa and cassava meal impaired fish performance. No differences were observed for dry matter, crude protein and body ash. The lower body fat accumulation was recorded for the tilapia fed palm kernel cake. The best economic indicators were found to diets containing palm kernel cake. The byproducts evaluated can be used up to 150 g/kg in feed formulation, providing good performance and economic rate for Nile tilapia.

  11. Analysis of production and environmental effects of Nile tilapia and white shrimp culture in Thailand

    DEFF Research Database (Denmark)

    Ferreira, J.G.; Falconer, L.; Kittiwanich, J.

    2015-01-01

    Two case studies from Southeast Asia are used to analyse production, environmental effects, and economic optimisation of Nile tilapia (Oreochromis niloticus) and white shrimp (Penaeus vannamei) pond culture. A projection of these data is made for the whole of Thailand. The results are analysed...... on a regional scale based on site selection using multi-criteria evaluation (MCE). Farm-scale culture was simulated for (i) tilapia monoculture in Chiang Rai; (ii) shrimp monoculture in Chanthaburi; and (iii) Integrated Multi-Trophic Aquaculture (IMTA) of tilapia and shrimp in Chon Buri. Together...... in ponds. Co-cultivation stimulates nitrogen dissolution (134 kg N cycle− 1), which is greater than in tilapia (96 kg N) or shrimp (52 kg N) monoculture, and doubles the NH4+ discharge to the environment (10.7 kg in tilapia monoculture, 20.5 kg in co-cultivation). However, eutrophication as a result...

  12. Effects of growth hormone transgenesis on metabolic rate, exercise performance and hypoxia tolerance in tilapia hybrids

    DEFF Research Database (Denmark)

    McKenzie, DJ; Martinez, R; Morales, A

    2003-01-01

    Swimming respirometry was employed to compare inactive metabolic rate (Rr), maximum metabolic rate (Rmax), resultant aerobic scope and maximum sustainable (critical) swimming speed (Ucrit), in growth hormone transgenic (GHT) and wild-type (W) tilapia Oreochromis sp. hybrids. Although the Rr of GHT...... tilapia was significantly (58%) higher than their W conspecifics, there were no significant differences in their net aerobic scope because GHT tilapia exhibited a compensatory increase in Rmax that was equal to their net increase in Rr. As a consequence, the two groups had the same Ucrit. The GHT and W...... tilapia also exhibited the same capacity to regulate oxygen uptake during progressive hypoxia, despite the fact that the GHT fish were defending a higher demand for O2. The results indicate that ectopic expression of GH raises metabolic rate in tilapia, but the fish compensate for this metabolic load...

  13. Identifications of Captive and Wild Tilapia Species Existing in Hawaii by Mitochondrial DNA Control Region Sequence

    Science.gov (United States)

    Wu, Liang; Yang, Jinzeng

    2012-01-01

    Background The tilapia family of the Cichlidae includes many fish species, which live in freshwater and saltwater environments. Several species, such as O. niloticus, O. aureus, and O. mossambicus, are excellent for aquaculture because these fish are easily reproduced and readily adapt to diverse environments. Historically, tilapia species, including O. mossambicus, S. melanotheron, and O. aureus, were introduced to Hawaii many decades ago, and the state of Hawaii uses the import permit policy to prevent O. niloticus from coming into the islands. However, hybrids produced from O. niloticus may already be present in the freshwater and marine environments of the islands. The purpose of this study was to identify tilapia species that exist in Hawaii using mitochondrial DNA analysis. Methodology/Principal Findings In this study, we analyzed 382 samples collected from 13 farm (captive) and wild tilapia populations in Oahu and the Hawaii Islands. Comparison of intraspecies variation between the mitochondrial DNA control region (mtDNA CR) and cytochrome c oxidase I (COI) gene from five populations indicated that mtDNA CR had higher nucleotide diversity than COI. A phylogenetic tree of all sampled tilapia was generated using mtDNA CR sequences. The neighbor-joining tree analysis identified seven distinctive tilapia species: O. aureus, O. mossambicus, O. niloticus, S. melanotheron, O. urolepies, T. redalli, and a hybrid of O. massambicus and O. niloticus. Of all the populations examined, 10 populations consisting of O. aureus, O. mossambicus, O. urolepis, and O. niloticus from the farmed sites were relatively pure, whereas three wild populations showed some degree of introgression and hybridization. Conclusions/Significance This DNA-based tilapia species identification is the first report that confirmed tilapia species identities in the wild and captive populations in Hawaii. The DNA sequence comparisons of mtDNA CR appear to be a valid method for tilapia species

  14. Trophic transfer of Cd from duckweed (Lemna minor L.) to tilapia (Oreochromis mossambicus).

    Science.gov (United States)

    Xue, Yan; Peijnenburg, Willie J G M; Huang, Jin; Wang, Dengjun; Jin, Yan

    2018-05-01

    The transfer of the toxic heavy metal Cd from duckweed (Lemna minor L.) to the freshwater fish tilapia (Oreochromis mossambicus) was investigated. Concentrations of Cd in different chemical forms in duckweed and in different tissues (gut, edible muscle, and remnants or residual) of tilapia (i.e., ethanol-extractable fraction [F E ], HCl-extractable fraction [F HCl ], and residual fraction [F R ]) were quantified, and the bioaccumulation factors (BAFs) of Cd in the tilapia body were calculated. Simple linear regression analysis was used to unravel the correlation and accumulation mechanisms of Cd along the short food chain. Our results showed that with increasing exposure concentrations of Cd (0-50 μM for duckweed and 0-10 μM for tilapia), the total, F E (F e,d )-, F HCl (F h,d )-, and F R (F r,d )-Cd concentrations in duckweed and different tissues of tilapia increased progressively. The Cd sources (aqueous or dietary) influenced the BAF for Cd accumulation in the whole body of tilapia. Furthermore, regression analyses yielded significant positive correlations (R 2 > 0.96) between the Cd concentration in duckweed and in both the 3 parts and the whole body of tilapia. This finding suggests that Cd transfer from duckweed to tilapia can be quantitatively evaluated when tilapia is exposed only to duckweed. In addition, the linear regression between Cd accumulation in whole tilapia and F e,d -, F h,d -, and F r,d -Cd showed that particularly the correlation with F e,d -Cd is statistically significant (p < 0.001). The accumulated Cd concentrations and chemical forms in tilapia tissues also positively correlated with Cd sources (solution or duckweed). Compared with waterborne exposure only, duckweed especially increased the accumulation of Cd in the gut of tilapia. Taken together, our findings support a strong dependence of Cd accumulation and transfer from duckweed to tilapia on its chemical forms, especially on F e,d -Cd. This knowledge may expedite more

  15. Chitosan extends the shelf-life of filleted tilapia ( Oreochromis niloticus) during refrigerated storage

    Science.gov (United States)

    Cao, Rong; Liu, Qi; Yin, Bangzhong; Wu, Biao

    2012-09-01

    Shelf-life extension of aquatic products is of significant economical importance. To determine the potential effect of chitosan on the shelf-life of filleted tilapia, this study analyzed the bacterial community diversity in fresh and spoiled tilapia fillets stored at (4 ± 1)°C and examined the antimicrobial activity of chitosan against relevant bacteria isolates. Results showed that Pseudomonas (20%) and Aeromonas (16%) were abundant in fresh tilapia fillets, whereas Pseudomonas (52%), Aeromonas (32%) and Staphylococcus (12%) were dominant in the spoiled samples. Chitosan showed wide-spectrum antibacterial activity against bacteria isolated from tilapia and 5.0 g L-1 chitosan was selected for application in preservation. We further determined the shelf-life of chitosan-treated, filleted tilapia stored at (4 ± 1)°C based on microbiological, biochemical and sensory analyses. Results showed that the shelf-life of chitosan-treated, filleted tilapia was extended to 12 d, whereas that of untreated, control samples was 6 d. These indicate that chitosan, as a natural preservative, has great application potential in the shelf-life extension of tilapia fillets.

  16. Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

    Science.gov (United States)

    Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

    2015-11-01

    In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study.

  17. Thermal preference predicts animal personality in Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Cerqueira, Marco; Rey, Sonia; Silva, Tome; Featherstone, Zoe; Crumlish, Margaret; MacKenzie, Simon

    2016-09-01

    Environmental temperature gradients provide habitat structure in which fish orientate and individual thermal choice may reflect an essential integrated response to the environment. The use of subtle thermal gradients likely impacts upon specific physiological and behavioural processes reflected as a suite of traits described by animal personality. In this study, we examine the relationship between thermal choice, animal personality and the impact of infection upon this interaction. We predicted that thermal choice in Nile tilapia Oreochromis niloticus reflects distinct personality traits and that under a challenge individuals exhibit differential thermal distribution. Nile tilapia were screened following two different protocols: 1) a suite of individual behavioural tests to screen for personality and 2) thermal choice in a custom-built tank with a thermal gradient (TCH tank) ranging from 21 to 33 °C. A first set of fish were screened for behaviour and then thermal preference, and a second set were tested in the opposite fashion: thermal then behaviour. The final thermal distribution of the fish after 48 h was assessed reflecting final thermal preferendum. Additionally, fish were then challenged using a bacterial Streptococcus iniae model infection to assess the behavioural fever response of proactive and reactive fish. Results showed that individuals with preference for higher temperatures were also classified as proactive with behavioural tests and reactive contemporaries chose significantly lower water temperatures. All groups exhibited behavioural fever recovering personality-specific thermal preferences after 5 days. Our results show that thermal preference can be used as a proxy to assess personality traits in Nile tilapia and it is a central factor to understand the adaptive meaning of animal personality within a population. Importantly, response to infection by expressing behavioural fever overrides personality-related thermal choice. © 2016 The Authors

  18. Characterization of a Novel Orthomyxo-like Virus Causing Mass Die-Offs of Tilapia

    Directory of Open Access Journals (Sweden)

    Eran Bacharach

    2016-04-01

    Full Text Available Tilapia are an important global food source due to their omnivorous diet, tolerance for high-density aquaculture, and relative disease resistance. Since 2009, tilapia aquaculture has been threatened by mass die-offs in farmed fish in Israel and Ecuador. Here we report evidence implicating a novel orthomyxo-like virus in these outbreaks. The tilapia lake virus (TiLV has a 10-segment, negative-sense RNA genome. The largest segment, segment 1, contains an open reading frame with weak sequence homology to the influenza C virus PB1 subunit. The other nine segments showed no homology to other viruses but have conserved, complementary sequences at their 5′ and 3′ termini, consistent with the genome organization found in other orthomyxoviruses. In situ hybridization indicates TiLV replication and transcription at sites of pathology in the liver and central nervous system of tilapia with disease.

  19. Shelf Life and Quality Study of Minced Tilapia with Nori and Hijiki Seaweeds as Natural Additives

    Directory of Open Access Journals (Sweden)

    Ingridy Simone Ribeiro

    2014-01-01

    Full Text Available The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage.

  20. Draft genome sequences of three Aeromonas hybrophila isolates from catfish and tilapia

    Science.gov (United States)

    Aeromonas hydrophila is a Gram-negative bacteria that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here we report the draft genomes of three A. hydrophila catfish and tilapia isolates....

  1. Effect of dietary protein on hybrid tilapia production in a biofloc technology system

    Science.gov (United States)

    In an outdoor biofloc technology (BFT) production system a complex of living organisms that includes phytoplankton, zooplankton, ciliates, nematodes, bacteria, all closely associated with particulate organic matter, is maintained suspended in the water column by continuous aeration. Tilapia grown in...

  2. Bioeconomic of profit maximization of red tilapia (Oreochromis sp.) culture using polynomial growth model

    Science.gov (United States)

    Wijayanto, D.; Kurohman, F.; Nugroho, RA

    2018-03-01

    The research purpose was to develop a model bioeconomic of profit maximization that can be applied to red tilapia culture. The development of fish growth model used polynomial growth function. Profit maximization process used the first derivative of profit equation to time of culture equal to zero. This research has also developed the equations to estimate the culture time to reach the target size of the fish harvest. The research proved that this research model could be applied in the red tilapia culture. In the case of this study, red tilapia culture can achieve the maximum profit at 584 days and the profit of Rp. 28,605,731 per culture cycle. If used size target of 250 g, the culture of red tilapia need 82 days of culture time.

  3. Shelf Life and Quality Study of Minced Tilapia with Nori and Hijiki Seaweeds as Natural Additives

    Science.gov (United States)

    Ribeiro, Ingridy Simone; Shirahigue, Ligianne Din; Ferraz de Arruda Sucasas, Lia; Anbe, Lika; da Cruz, Pedro Gomes; Gallo, Cláudio Rosa; Carpes, Solange Teresinha; Marques, Marcos José; Oetterer, Marília

    2014-01-01

    The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage. PMID:25478593

  4. Use of fish processing waste as protein source in diet for Nile tilapia (Orechromis niloticus

    Directory of Open Access Journals (Sweden)

    Chotipuntu, P.

    2005-02-01

    Full Text Available Five diets were prepared using fish processing waste meal (FMFP to replace fish meal (FM at inclusion levels of 0, 25, 50, 75 and 100%. Frog diet was used as a control diet. Nile tilapia (Oreochromis niloticus were reared in laboratory conditions for 8 weeks. It was found that substitution levels of protein from FMFP in the tested diets reduced growth and feed efficiency of tilapia (p<0.05. However, the differences looks like significant trend especially that between the 100% substitution level and the frog diet. Substitution of FM by FMFD at 75% reduced cost of feed by 15.35%. It was concluded that up to 75% inclusion of FMFD in the diet of tilapia could support normal growth of Nile tilapia with the potential for substitution of FM.

  5. Phosphorous digestibility and activity of intestinal phytase in hybrid tilapia, Oreochromis niloticus X O. aureus

    Science.gov (United States)

    La Vorgna, M.W.; Hafez, Y.; Hughes, S.G.; Handwerker, T.

    2003-01-01

    Experiments were conducted to determine the degree to which phytate-bound phosphorus from plant protein sources could be used by hybrid tilapia (Oreochromis niloticus X O. aureus). Utilizing an inert marker technique with chromic oxide, hybrid tilapia in our study were effective at utilizing both inorganic and phytate phosphorus as evidenced by average apparent digestibility values of 93.2% and 90.0% for total and phytate phosphorus, respectively. Analysis of the intestinal brush border membrane of the tilapia revealed enzyme activity that was capable of hydrolyzing phytic acid. The presence of phytic acid hydrolyzing enzyme activity in the intestinal brush border provides a probable mechanism by which these hybrid tilapia are able to utilize phytate phosphorus effectively. ?? 2003 by The Haworth Press, Inc. All rights reserved.

  6. Mercury exposure in the freshwater tilapia Oreochromis niloticus

    Energy Technology Data Exchange (ETDEWEB)

    Wang Rui [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wong Minghung [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.h [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

    2010-08-15

    Mercury (Hg) can be strongly accumulated and biomagnified along aquatic food chain, but the exposure pathway remains little studied. In this study, we quantified the uptake and elimination of both inorganic mercury [as Hg(II)] and methylmercury (as MeHg) in an important farmed freshwater fish, the tilapia Oreochromis niloticus, using {sup 203}Hg radiotracer technique. The dissolved uptake rates of both mercury species increased linearly with Hg concentration (tested at ng/L levels), and the uptake rate constant of MeHg was 4 times higher than that of Hg(II). Dissolved uptake of mercury was highly dependent on the water pH and dissolved organic carbon concentration. The dietborne assimilation efficiency of MeHg was 3.7-7.2 times higher than that of Hg(II), while the efflux rate constant of MeHg was 7.1 times lower. The biokinetic modeling results showed that MeHg was the greater contributor to the overall mercury bioaccumulation and dietary exposure was the predominant pathway. - Trophic transfer was the predominant pathway for mercury accumulation in tilapia, and methylmercury was more important in contributing to Hg accumulation than Hg(II).

  7. Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

    Directory of Open Access Journals (Sweden)

    Henry-Silva Gustavo Gonzaga

    2006-01-01

    Full Text Available The effluents from fish farming can increase the quantity of suspended solids and promote the enrichment of nitrogen and phosphorus in aquatic ecosystems. In this context, the aim of this work was to evaluate the efficiency of three species of floating aquatic macrophytes (Eichhornia crassipes, Pistia stratiotes and Salvinia molesta to treat effluents from Nile tilapia culture ponds. The effluent originated from a 1,000-m² pond stocked with 2,000 male Nile tilapia Oreochromis niloticus. The treatment systems consisted of 12 experimental tanks, three tanks for each macrophyte species, and three control tanks (without plants. Water samples were collected from the: (i fish pond source water, (ii effluent from fish pond and (iii effluents from the treatment tanks. The following water variables were evaluated: turbidity, total and dissolved nitrogen, ammoniacal-N, nitrate-N, nitrite-N, total phosphorus and dissolved phosphorus. E. crassipes and P. stratiotes were more efficient in total phosphorus removal (82.0% and 83.3%, respectively and total nitrogen removal (46.1% and 43.9%, respectively than the S. molesta (72.1% total phosphorus and 42.7% total nitrogen and the control (50.3% total phosphorus and 22.8% total nitrogen, indicating that the treated effluents may be reused in the aquaculture activity.

  8. Environmental blue light prevents stress in the fish Nile tilapia

    Directory of Open Access Journals (Sweden)

    Volpato G.L.

    2001-01-01

    Full Text Available The present study aimed to test the effects of blue, green or white light on the stress response of the Nile tilapia, Oreochromis niloticus (L.. Each color was tested on two groups of isolated adult Nile tilapia (8 replicates each: one being subjected to confinement stress, and the other not (control. A different environmental color was imposed on each compartment by covering the light source with cellophane of the respective color (green or blue; no cellophane was used for white light. The intensity of green, white and blue lights was 250, 590 and 250 lux, respectively. Basal plasma cortisol levels were determined for each fish prior to the experimental procedures. The fish were confined by being displaced toward one side of the aquarium using an opaque partition for 1 h both in the morning and the afternoon of the two consecutive days of the test. At the end of this 48-h period, plasma cortisol levels were measured again. Basal cortisol levels (ng/ml were similar for each group (ANOVA, F(2;42 = 0.77, P = 0.47. Thus, plasma cortisol levels were analyzed in terms of variation from their respective basal level. After confinement, plasma cortisol levels were not increased in fish submitted to a blue light environment. Thus, blue light prevents the confinement-induced cortisol response, an effect not necessarily related to light intensity.

  9. The Antibacterial Effect of Grape Seed Extract on Tilapia

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    R Golvardzadeh

    2016-05-01

    Full Text Available Abstract Introduction: Medicinal plants are highly taken into consideration due to having natural antimicrobial compounds which Iran can be introduced as one of the richest sources of medicinal plants. Hence, the purpose of this study was to determine the antibacterial activities of grape seed extract on shelf life of tilapia. Methods: The prepared fish were divided into 2 groups: the first group was treated by dipping for 30 min in grape seed extract (1.5%v/v, and the second group was dipped in distilled water as the control sample. The control and treated fish samples were analyzed for microbiological (total count of mesophilic aerobic micro organisms, PTC and sensory characteristictis over a perid of 20 days. Results: The study results indicated the extract treatment group significantly delayed (p<0.05 the spoilage process in comparison with the control group, which the total count of psychotrophic bacteria remained lower than the proposed acceptable limit (7 log cfu/g. According to sensory analysis, the treated fish with grape seed extract represented the highest quality during the storage. Conclusions: The present study findings revealed that grape seed extract seemed to be extremely effective in extending the shelf life of tilapia fish fillet during the refrigerated storage.

  10. Visual communication stimulates reproduction in Nile tilapia, Oreochromis niloticus (L.).

    Science.gov (United States)

    Castro, A L S; Gonçalves-de-Freitas, E; Volpato, G L; Oliveira, C

    2009-04-01

    Reproductive fish behavior is affected by male-female interactions that stimulate physiological responses such as hormonal release and gonad development. During male-female interactions, visual and chemical communication can modulate fish reproduction. The aim of the present study was to test the effect of visual and chemical male-female interaction on the gonad development and reproductive behavior of the cichlid fish Nile tilapia, Oreochromis niloticus (L.). Fifty-six pairs were studied after being maintained for 5 days under one of the four conditions (N = 14 for each condition): 1) visual contact (V); 2) chemical contact (Ch); 3) chemical and visual contact (Ch+V); 4) no sensory contact (Iso) - males and females isolated. We compared the reproductive behavior (nesting, courtship and spawning) and gonadosomatic index (GSI) of pairs of fish under all four conditions. Visual communication enhanced the frequency of courtship in males (mean +/- SEM; V: 24.79 +/- 3.30, Ch+V: 20.74 +/- 3.09, Ch: 0.1 +/- 0.07, Iso: 4.68 +/- 1.26 events/30 min; P communication did not affect the reproductive behavior of pairs nor did it enhance the effects of visual contact. Therefore, male-female visual communication is an effective cue, which stimulates reproduction among pairs of Nile tilapia.

  11. DNA replication and repair of Tilapia cells: Pt. 2

    International Nuclear Information System (INIS)

    Chen, J.D.; Yew, F.H.

    1988-01-01

    TO-2 is a fish cell line derived from the Tilapia ovary. It grows over a wide range of temperature (15-34 0 C). We report the effects of temperature on DNA replication and u.v. repair in TO-2 cells. When the cells were moved from 31 0 C to the sublethal high temperature of 37 0 C, the rate of DNA synthesis first decreased to 60%, then speedy recovery soon set in, and after 8h at 37 0 C the rate of DNA synthesis overshot the 31 0 C control level by 180%. When moved to low temperature (18 0 C) Tilapia cells also showed an initial suppression of DNA synthesis before settling at 30% of the control level. U.V. reduced but could not block DNA synthesis completely. The inhibition was overcome in 3h at 37, 31 and 25 0 C, but not at 18 0 C. Initiation of nascent DNA synthesis was blocked at 4Jm -2 in TO-2 cells compared with ≤ 1Jm -2 in mammalian cells. After 9Jm -2 u.v. irradiation, low molecular weight DNA replication intermediates started to accumulate. TO-2 cells showed low levels of u.v.-induced excision repair. (author)

  12. Mercury exposure in the freshwater tilapia Oreochromis niloticus

    International Nuclear Information System (INIS)

    Wang Rui; Wong Minghung; Wang Wenxiong

    2010-01-01

    Mercury (Hg) can be strongly accumulated and biomagnified along aquatic food chain, but the exposure pathway remains little studied. In this study, we quantified the uptake and elimination of both inorganic mercury [as Hg(II)] and methylmercury (as MeHg) in an important farmed freshwater fish, the tilapia Oreochromis niloticus, using 203 Hg radiotracer technique. The dissolved uptake rates of both mercury species increased linearly with Hg concentration (tested at ng/L levels), and the uptake rate constant of MeHg was 4 times higher than that of Hg(II). Dissolved uptake of mercury was highly dependent on the water pH and dissolved organic carbon concentration. The dietborne assimilation efficiency of MeHg was 3.7-7.2 times higher than that of Hg(II), while the efflux rate constant of MeHg was 7.1 times lower. The biokinetic modeling results showed that MeHg was the greater contributor to the overall mercury bioaccumulation and dietary exposure was the predominant pathway. - Trophic transfer was the predominant pathway for mercury accumulation in tilapia, and methylmercury was more important in contributing to Hg accumulation than Hg(II).

  13. X-ray-induced changes in growth of Mozambique tilapia

    International Nuclear Information System (INIS)

    Jana, B.B.; Basu, M.

    1995-01-01

    Early fry (30 d postfertilization) and 7-8-week-old Mozambique tilapias (Tilapia mossambica) were exposed to X rays in dosages of 50, 100, 200, 300, 400 or 500 roentgens and reared in outdoor culture tanks between May 1981 and October 1988. Fish of either sex that were irradiated as fry grew faster than controls at all test X-ray doses. Among fish irradiated at 7-8 weeks, males grew significantly faster, but females grew significantly slower, than controls at all test doses. X-ray-induced changes in growth were dose-dependent: growth rates of fry (both sexes) and of juvenile males rose relative to those of controls with increased radiation dose. The growth increase per unit of radiation dose was higher for fry than for older juveniles. The length-weight regression was steeper for irradiated males than for controls. The average weights of F 1 offspring of irradiated fish were greatly reduced as compared with controls, which suggests the transfer of the detrimental effects of X rays from irradiated parents to their offspring. 39 refs., 3 figs., 3 tabs

  14. THE PREVALENCE OF Salmonella sp., Listeria sp. AND Aeromonas spp. IN CATFISH (CLARIAS (Clarias gariepinus AND TILAPIA (Tilapia mossambica BY PELLETING METHOD

    Directory of Open Access Journals (Sweden)

    Titik Budiati

    2013-06-01

    Full Text Available The aim of this study was to modify the isolation methods of Aeromonas sp., Salmonella spp., and Listeria sp. in catfish (Clarias gariepinus and tilapia (Tilapia mossambica obtained from wet markets and ponds in Malaysia by pelleting the sample. A total of 108 samples (32 catfish intestines, 32 tilapia intestines, and 44 water samples were obtained from nine wet markets and eight ponds. The modified method was employed by pelleting the samples and followed by either implementing pre-enrichment or without pre-enrichment on the isolation of Salmonella and Listeria spp. The modified method (by pelleting the sample in combination with pre-enrichment was the most efficient for Salmonella and Listeria isolation. The sensitivity of the modified Salmonella isolation method was 0.53 and 0.73 for fish and water samples, respectively. The sensitivity of the modified Listeria method was 1 and 0.92 for fish and water samples, respectively. However, the sensitivity of the method by pelleting the sample was similar to those of non-pelleting the sample on Aeromonas isolation. Five species of Aeromonas spp., seven serovars of Salmonella sp., and four species of Listeria sp. were observed in catfish, tilapia and water samples. Overall, by pelleting the sample offered the beneficial to isolate Aeromonas spp., Salmonella sp. and Listeria spp. in catfish, tilapia and water.

  15. Molecular cloning, functional identification and expressional analyses of FasL in Tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Ma, Tai-yang; Wu, Jin-ying; Gao, Xiao-ke; Wang, Jing-yuan; Zhan, Xu-liang; Li, Wen-sheng

    2014-10-01

    FasL is the most extensively studied apoptosis ligand. In 2000, tilapia FasL was identified using anti-human FasL monoclonal antibody by Evans's research group. Recently, a tilapia FasL-like protein of smaller molecule weight was predicted in Genbank (XM_003445156.2). Based on several clues drawn from previous studies, we cast doubt on the authenticity of the formerly identified tilapia FasL. Conversely, using reverse transcription polymerase chain reaction (RT-PCR), the existence of the predicted FasL-like was verified at the mRNA level (The Genbank accession number of the FasL mRNA sequence we cloned is KM008610). Through multiple alignments, this FasL-like protein was found to be highly similar to the FasL of the Japanese flounder. Moreover, we artificially expressed the functional region of the predicted protein and later confirmed its apoptosis-inducing activity using a methyl thiazolyl tetrazolium (MTT) assay, Annexin-V/Propidium iodide (PI) double staining, and DNA fragment detection. Supported by these evidences, we suggest that the predicted protein is the authentic tilapia FasL. To advance this research further, tilapia FasL mRNA and its protein across different tissues were quantified. High expression levels were identified in the tilapia immune system and sites where active cell turnover conservatively occurs. In this regard, FasL may assume an active role in the immune system and cell homeostasis maintenance in tilapia, similar to that shown in other species. In addition, because the distribution pattern of FasL mRNA did not synchronize with that of the protein, post-transcriptional expression regulation is suggested. Such regulation may be dominated by potential adenylate- and uridylate-rich elements (AREs) featuring AUUUA repeats found in the 3' untranslated region (UTR) of tilapia FasL mRNA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Proposal of a production and management index (PMI) for tilapia farms.

    Science.gov (United States)

    Muniesa, A; Rey-Castaño, A L; Ruiz-Zarzuela, I; Guarín, M; Iregui, C; de Blas, I

    2016-11-01

    Tilapia is one of the most important species in aquaculture; however, there is no available index to show the performance of a production unit. It is desirable to assess the productivity using indexes, such as the production and management index for shrimps and the European production efficacy factor for broilers. These indexes are based on data production: growth, survival, and feed conversion of a full production cycle. Taking into account these parameters, we propose a production and management index (PMI) for tilapia that is applicable for a specific period of the production cycle. For the construction and validation of the PMI we have used production data from 8,614 monthly records of 2 tilapia farms in Huila Department (Colombia), and because of the complexity of tilapia management, different anomalous situations have been detected and then defined as exceptions. As a result, 419 records were considered extreme values because 1 or more exceptions were met. The value of the PMI varies from 0 (the worst situation) to 3.55, which reflects high variability. We have constructed a PMI for tilapia as the product of 3 elements to obtain a positive value index. Instead of classic parameters, we had to calculate an adapted version of them: the relative average daily growth, the survival (as a complementary value of the estimated monthly mortality), and a feed conversion ratio index. To assess the utility of the PMI, some comparisons were performed using records from black and red tilapia. We observed significant differences depending on tilapia strain (PMI = 1.0248 vs. PMI = 1.1661; tilapia farmers, despite the complexity of the calculation.

  17. Tilapia-waste flour as a natural nutritional replacer for bread: A consumer perspective

    Science.gov (United States)

    Mársico, Eliane T.; Soares Junior, Manoel S.; Deliza, Rosires; de Oliveira, Denize C. R.; Conte-Junior, Carlos A.

    2018-01-01

    Six bread formulations with different levels of tilapia-waste flour (BTF0%, BTF2.5%, BTF5%, BTF10%, BTF15%, and BTF20%) were analyzed for nutritional composition and sensory characterization. Tilapia-waste flour (TF) increased (P preference. Despite this apparent consumer preference for low or no levels, TF can be added to bread at levels below 12.17% (P consumer rejection. TF changed (P consumer and industry requirements. PMID:29723283

  18. Additive genetic variation in resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalactiae capsular type Ib: is genetic resistance correlated?

    Science.gov (United States)

    Streptococcus (S.) iniae and S. agalactiae are both economically important Gram positive bacterial pathogens affecting the globally farmed tilapia (Oreochromis spp.). Historically control of these bacteria in tilapia culture has included biosecurity, therapeutants and vaccination strategies. Genet...

  19. MicroRNA repertoire for functional genome research in tilapia identified by deep sequencing.

    Science.gov (United States)

    Yan, Biao; Wang, Zhen-Hua; Zhu, Chang-Dong; Guo, Jin-Tao; Zhao, Jin-Liang

    2014-08-01

    The Nile tilapia (Oreochromis niloticus; Cichlidae) is an economically important species in aquaculture and occupies a prominent position in the aquaculture industry. MicroRNAs (miRNAs) are a class of noncoding RNAs that post-transcriptionally regulate gene expression involved in diverse biological and metabolic processes. To increase the repertoire of miRNAs characterized in tilapia, we used the Illumina/Solexa sequencing technology to sequence a small RNA library using pooled RNA sample isolated from the different developmental stages of tilapia. Bioinformatic analyses suggest that 197 conserved and 27 novel miRNAs are expressed in tilapia. Sequence alignments indicate that all tested miRNAs and miRNAs* are highly conserved across many species. In addition, we characterized the tissue expression patterns of five miRNAs using real-time quantitative PCR. We found that miR-1/206, miR-7/9, and miR-122 is abundantly expressed in muscle, brain, and liver, respectively, implying a potential role in the regulation of tissue differentiation or the maintenance of tissue identity. Overall, our results expand the number of tilapia miRNAs, and the discovery of miRNAs in tilapia genome contributes to a better understanding the role of miRNAs in regulating diverse biological processes.

  20. Comparative Transcriptome Analysis Identifies Candidate Genes Related to Skin Color Differentiation in Red Tilapia.

    Science.gov (United States)

    Zhu, Wenbin; Wang, Lanmei; Dong, Zaijie; Chen, Xingting; Song, Feibiao; Liu, Nian; Yang, Hui; Fu, Jianjun

    2016-08-11

    Red tilapia is becoming more popular for aquaculture production in China in recent years. However, the pigmentation differentiation in genetic breeding is the main problem limiting its development of commercial red tilapia culture and the genetic basis of skin color variation is still unknown. In this study, we conducted Illumina sequencing of transcriptome on three color variety red tilapia. A total of 224,895,758 reads were generated, resulting in 160,762 assembled contigs that were used as reference contigs. The contigs of red tilapia transcriptome had hits in the range of 53.4% to 86.7% of the unique proteins of zebrafish, fugu, medaka, three-spined stickleback and tilapia. And 44,723 contigs containing 77,423 simple sequence repeats (SSRs) were identified, with 16,646 contigs containing more than one SSR. Three skin transcriptomes were compared pairwise and the results revealed that there were 148 common significantly differentially expressed unigenes and several key genes related to pigment synthesis, i.e. tyr, tyrp1, silv, sox10, slc24a5, cbs and slc7a11, were included. The results will facilitate understanding the molecular mechanisms of skin pigmentation differentiation in red tilapia and accelerate the molecular selection of the specific strain with consistent skin colors.

  1. Isolation and Pathogenicity of Streptococcus iniae in Cultured Red Hybrid Tilapia in Malaysia.

    Science.gov (United States)

    Rahmatullah, M; Ariff, M; Kahieshesfandiari, M; Daud, H M; Zamri-Saad, M; Sabri, M Y; Amal, M N A; Ina-Salwany, M Y

    2017-12-01

    This study describes the isolation and pathogenicity of Streptococcus iniae in cultured red hybrid tilapia (Nile Tilapia Oreochromis niloticus × Mozambique Tilapia O. mossambicus) in Malaysia. The isolated gram-positive S. iniae appeared punctiform, transparently white, catalase and oxidase negative and produced complete β-hemolysis on blood agar, while a PCR assay resulted in the amplification of the 16 S rRNA gene and lactate oxidase encoded genes. The isolate was sensitive to tetracycline, vancomycin, and bacitracin but was resistant to streptomycin, ampicillin, penicillin, and erythromycin. Pathogenicity trials conducted in local red hybrid tilapia (mean ± SE = 20.00 ± 0.45 g) showed 90.0, 96.7, and 100.0% mortality within 14 d postinfection following intraperitoneal exposure to 10 4 , 10 6 , and 10 8 CFU/mL of the pathogen, respectively. The clinical signs included erratic swimming, lethargy, and inappetance at 6 h postinfection, while mortality was recorded at less than 24 h postinfection in all infected groups. The LD 50-336 h of S. iniae against the red hybrid tilapia was 10 2 CFU/mL. The post mortem examinations revealed congested livers, kidneys, and spleens of the infected fish. This is the first report of S. iniae experimental infection in cultured red hybrid tilapia in Malaysia. Received January 20, 2017; accepted July 16, 2017.

  2. Detection of Tilapia Lake Virus in Clinical Samples by Culturing and Nested Reverse Transcription-PCR.

    Science.gov (United States)

    Kembou Tsofack, Japhette Esther; Zamostiano, Rachel; Watted, Salsabeel; Berkowitz, Asaf; Rosenbluth, Ezra; Mishra, Nischay; Briese, Thomas; Lipkin, W Ian; Kabuusu, Richard M; Ferguson, Hugh; Del Pozo, Jorge; Eldar, Avi; Bacharach, Eran

    2017-03-01

    Tilapia are an important group of farmed fish that serve as a significant protein source worldwide. In recent years, substantial mortality of wild tilapia has been observed in the Sea of Galilee and in commercial ponds in Israel and Ecuador. We have identified the etiological agent of these mass die-offs as a novel orthomyxo-like virus and named it tilapia lake virus (TiLV). Here, we provide the conditions for efficient isolation, culturing, and quantification of the virus, including the use of susceptible fish cell lines. Moreover, we describe a sensitive nested reverse transcription-PCR (RT-PCR) assay allowing the rapid detection of TiLV in fish organs. This assay revealed, for the first time to our knowledge, the presence of TiLV in diseased Colombian tilapia, indicating a wider distribution of this emerging pathogen and stressing the risk that TiLV poses for the global tilapia industry. Overall, the described procedures should provide the tilapia aquaculture industry with important tools for the detection and containment of this pathogen. Copyright © 2017 American Society for Microbiology.

  3. Inactivation kinetics of formaldehyde on N-acetyl-β-D-glucosaminidase from Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zhang, Wei-Ni; Bai, Ding-Ping; Lin, Xin-Yu; Chen, Qing-Xi; Huang, Xiao-Hong; Huang, Yi-Fan

    2014-04-01

    Formaldehyde is a widely used sanitizer in aquaculture in China, while the appropriate concentration is not available to be used effectively and without damage to tilapia much less to its reproductive function. N-acetyl-β-D-glucosaminidase (EC 3.2.1.52, NAGase), hydrolyzing the oligomers of N-acetyl-β-D-glucosamine into monomer, is proved to be correlated with reproduction of male animals. In this paper, NAGase from spermary of tilapia was chosen as the material to study the effects of formaldehyde on its activity in order to further investigate the effects of formaldehyde use on tilapia reproduction. The results showed the relationship between the residual enzyme activity and the concentration of formaldehyde was concentration dependent, and the IC50 value was estimated to be 3.2 ± 0.1 %. Appropriate concentration of formaldehyde leaded to competitive reversible inhibition on tilapia NAGase. Moreover, formaldehyde could reduce the thermal and pH stability of the enzyme. The inactivation kinetics of formaldehyde on the enzyme was studied using the kinetic method of substrate reaction. The inactivation model was setup, and the rate constants were determined. The results showed that the inactivation of formaldehyde on tilapia NAGase was a slow, reversible reaction with partially residual activity. The results will give some basis to determine the concentration of formaldehyde used in tilapia culture.

  4. Detection of Tilapia Lake Virus in Clinical Samples by Culturing and Nested Reverse Transcription-PCR

    Science.gov (United States)

    Kembou Tsofack, Japhette Esther; Zamostiano, Rachel; Watted, Salsabeel; Berkowitz, Asaf; Rosenbluth, Ezra; Mishra, Nischay; Briese, Thomas; Lipkin, W. Ian; Kabuusu, Richard M.; Ferguson, Hugh; del Pozo, Jorge

    2016-01-01

    ABSTRACT Tilapia are an important group of farmed fish that serve as a significant protein source worldwide. In recent years, substantial mortality of wild tilapia has been observed in the Sea of Galilee and in commercial ponds in Israel and Ecuador. We have identified the etiological agent of these mass die-offs as a novel orthomyxo-like virus and named it tilapia lake virus (TiLV). Here, we provide the conditions for efficient isolation, culturing, and quantification of the virus, including the use of susceptible fish cell lines. Moreover, we describe a sensitive nested reverse transcription-PCR (RT-PCR) assay allowing the rapid detection of TiLV in fish organs. This assay revealed, for the first time to our knowledge, the presence of TiLV in diseased Colombian tilapia, indicating a wider distribution of this emerging pathogen and stressing the risk that TiLV poses for the global tilapia industry. Overall, the described procedures should provide the tilapia aquaculture industry with important tools for the detection and containment of this pathogen. PMID:27974544

  5. Tgm1-like transglutaminases in tilapia (Oreochromis mossambicus.

    Directory of Open Access Journals (Sweden)

    Sandra I Rodriguez Cruz

    Full Text Available Among the adaptations of aquatic species during evolution of terrestrial tetrapods was the development of an epidermis preventing desiccation. In present day mammals, keratinocytes of the epidermis, using a membrane-bound transglutaminase (Tgm1, accomplish this function by synthesizing a scaffold of cross-linked protein to which a lipid envelope is attached. This study characterizes the abilities of two homologous transglutaminase isozymes in the teleost fish tilapia to form cross-linked protein structures and their expression in certain tissues. Results indicate they are capable of membrane localization and of generating cellular structures resistant to detergent solubilization. They are both expressed in epithelial cells of the lip, buccal cavity and tips of gill filaments. Adaptation of transglutaminase use in evolution of terrestrial keratinocytes evidently involved refinements in tissue expression, access to suitable substrate proteins and activation of cross-linking during terminal differentiation.

  6. Blood cues induce antipredator behavior in Nile tilapia conspecifics.

    Directory of Open Access Journals (Sweden)

    Rodrigo Egydio Barreto

    Full Text Available In this study, we show that the fish Nile tilapia displays an antipredator response to chemical cues present in the blood of conspecifics. This is the first report of alarm response induced by blood-borne chemical cues in fish. There is a body of evidence showing that chemical cues from epidermal 'club' cells elicit an alarm reaction in fish. However, the chemical cues of these 'club' cells are restricted to certain species of fish. Thus, as a parsimonious explanation, we assume that an alarm response to blood cues is a generalized response among animals because it occurs in mammals, birds and protostomian animals. Moreover, our results suggest that researchers must use caution when studying chemically induced alarm reactions because it is difficult to separate club cell cues from traces of blood.

  7. Effect of temperature on routine metabolism in Tilapia rendalli boulenger

    Energy Technology Data Exchange (ETDEWEB)

    Caulton, M.S.

    1977-12-01

    Using a continuous flow respirometer it was shown that young Tilapia rendalli had three distinct phases of oxygen consumption over the temperature range of 17 to 40/sup 0/C. In the first phase (17 to 28/sup 0/C) the metabolic energy demand followed the normal logarithmic increase with increasing temperature. Between 28 and 37/sup 0/C the increased oxygen uptake was suppressed and showed a relatively small increase with increasing temperature. This feature was believed to be a significant energy saving function important to the growth of these fish which feed in the warm eulitoral margins of lakes during the day. The final phase shows a return to the original logarithmic increase in oxygen consumption. These results were related to, and compared with, actual changes in biomass at various temperatures and the theoretical and actual biomass changes were found to compare favorably.

  8. Safety of florfenicol administered in feed to tilapia (Oreochromis sp.)

    Science.gov (United States)

    Gaikowski, Mark P.; Wolf, Jeffrey C.; Schleis, Susan M.; Tuomari, Darrell; Endris, Richard G.

    2013-01-01

    The safety of Aquaflor® (50% w/w florfenicol [FFC]) incorporated in feed then administered to tilapia for 20 days (2x the recommended duration) at 0, 15, 45, or 75 mg/kg body weight/day (0, 1, 3, or 5x the recommended dose of 15 mg FFC/kg BW/d) was investigated. Mortality, behavioral change, feed consumption, body size, and gross and microscopic lesions were determined. Estimated delivered doses were >96.9% of target. Three unscheduled mortalities occurred but were considered incidental since FFC-related findings were not identified. Feed consumption was only affected during the last 10 dosing days when the 45 and 75 mg/kg groups consumed only 62.5% and 55.3% of the feed offered, respectively. There were significant, dose-dependent reductions in body size in the FFC-dose groups relative to the controls. Treatment-related histopathological findings included increased severity of lamellar epithelial hyperplasia, increased incidence of lamellar adhesions, decreased incidence of lamellar telangiectasis in the gills, increased glycogen-type and lipid-type hepatocellular vacuolation in the liver, decreased lymphocytes, increased blast cells, and increased individual cell necrosis in the anterior kidney, and tubular epithelial degeneration and mineralization in the posterior kidney. These changes are likely to be of minimal clinical relevance, given the lack of mortality or morbidity observed. This study has shown that FFC, when administered in feed to tilapia at the recommended dose (15 mg FFC/kg BW/day) for 10 days would be well tolerated.

  9. Visual communication stimulates reproduction in Nile tilapia, Oreochromis niloticus (L.

    Directory of Open Access Journals (Sweden)

    A.L.S. Castro

    2009-04-01

    Full Text Available Reproductive fish behavior is affected by male-female interactions that stimulate physiological responses such as hormonal release and gonad development. During male-female interactions, visual and chemical communication can modulate fish reproduction. The aim of the present study was to test the effect of visual and chemical male-female interaction on the gonad development and reproductive behavior of the cichlid fish Nile tilapia, Oreochromis niloticus (L.. Fifty-six pairs were studied after being maintained for 5 days under one of the four conditions (N = 14 for each condition: 1 visual contact (V; 2 chemical contact (Ch; 3 chemical and visual contact (Ch+V; 4 no sensory contact (Iso - males and females isolated. We compared the reproductive behavior (nesting, courtship and spawning and gonadosomatic index (GSI of pairs of fish under all four conditions. Visual communication enhanced the frequency of courtship in males (mean ± SEM; V: 24.79 ± 3.30, Ch+V: 20.74 ± 3.09, Ch: 0.1 ± 0.07, Iso: 4.68 ± 1.26 events/30 min; P < 0.05, two-way ANOVA with LSD post hoc test, induced spawning in females (3 spawning in V and also 3 in Ch+V condition, and increased GSI in males (mean ± SEM; V: 1.39 ± 0.08, Ch+V: 1.21 ± 0.08, Ch: 1.04 ± 0.07, Iso: 0.82 ± 0.07%; P < 0.05, two-way ANOVA with LSD post hoc test. Chemical communication did not affect the reproductive behavior of pairs nor did it enhance the effects of visual contact. Therefore, male-female visual communication is an effective cue, which stimulates reproduction among pairs of Nile tilapia.

  10. Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China.

    Science.gov (United States)

    Li, Kang; Clausen, Jesper Hedegaard; Murrell, K Darwin; Liu, Liping; Dalsgaard, Anders

    2013-11-15

    Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1.5%) of trematode infections (Heterophyidae and Echinostomatidae). Integrated systems using animal manure and latrine wastes as fertilizer did not show a higher prevalence of FZT. Because it was not clear whether the low risk of infection was attributable to existing effective pond management practices or a low risk of spillover of FZT from area sylvatic reservoir hosts, a survey of local wild-caught fish was conducted. Five species of FZT were discovered from a total of 271 wild-caught fish and a mean infection density of 4.0 metacercariae/100g; FZT discovered included intestinal flukes (Haplorchis spp., Procerovum varium, and Metagonimus spp.) and metacercariae tentatively identified as Clonorchis sinenesis. The common occurrence of FZT in wild-caught fish suggests that the presence of FZT in local wild animal reservoirs is substantial, and that although the current aquaculture management systems for tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Ancestral genomic duplication of the insulin gene in tilapia: An analysis of possible implications for clinical islet xenotransplantation using donor islets from transgenic tilapia expressing a humanized insulin gene.

    Science.gov (United States)

    Hrytsenko, Olga; Pohajdak, Bill; Wright, James R

    2016-07-03

    Tilapia, a teleost fish, have multiple large anatomically discrete islets which are easy to harvest, and when transplanted into diabetic murine recipients, provide normoglycemia and mammalian-like glucose tolerance profiles. Tilapia insulin differs structurally from human insulin which could preclude their use as islet donors for xenotransplantation. Therefore, we produced transgenic tilapia with islets expressing a humanized insulin gene. It is now known that fish genomes may possess an ancestral duplication and so tilapia may have a second insulin gene. Therefore, we cloned, sequenced, and characterized the tilapia insulin 2 transcript and found that its expression is negligible in islets, is not islet-specific, and would not likely need to be silenced in our transgenic fish.

  12. Co-induction of hepatic IGF-I and progranulin mRNA by growth hormone in tilapia, Oreochromis mossambiccus

    Science.gov (United States)

    Like IGF-I, progranulin (pgrn) is a growth factor involved in tumorigenesis and wound healing. We report here the identification and characterization of pgrn cDNA in tilapia and the regulation of its expression by growth hormone(GH). The tilapia pgrn cDNA was cloned by RT-PCR ampliWcation, using g...

  13. Resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalactiae Ib is heritable but not correlated

    Science.gov (United States)

    Tilapia (Oreochromis sp.) are an important source of protein with an economic value approaching US $8 billion yearly. Streptococcal disease, caused by Streptococcus iniae and S. agalactiae (both Gram positive bacteria), is an emerging or re-emerging disease negatively affecting tilapia aquaculture w...

  14. Resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalatiae Ib is heritable but not correlated

    Science.gov (United States)

    Tilapia (Oreochromis sp.) are an important source of protein with an ecomonic value approaching US $8 billion yearly. Streptococcal disease, caused by Streptococcus iniae and S. agalactiae (both Gram positive bacteria), is an emerging or re-emerging disease negatively affecting tilapia aquaculture w...

  15. Complete genome sequence of Edwardsiella ictaluri isolate RUSVM-1 recovered from nile tilapia (Oreochromis niloticus) in the Western Hemisphere

    Science.gov (United States)

    Edwardsiella ictaluri is a Gram-negative, bacillus that has recently been implicated in disease outbreaks in tilapia and zebrafish. We report here the complete and annotated genome of an isolate from a Nile Tilapia (Oreochromis niloticus), which contains a chromosome of 3,630,639 bp and two plasmids...

  16. Controlled challenge experiment demonstrates substantial additive genetic variation in resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae

    Science.gov (United States)

    Streptococcus iniae is an etiologic agent of streptococcal disease in tilapia and is one of several Streptococcus spp. that negatively impact worldwide tilapia production. Methods for the prevention and control of S. iniae include vaccines, management strategies, and antibiotics. A complimentary pre...

  17. Genetic Relatedness of Salmonella Serovars Isolated from Catfish (Clarias gariepinus) and Tilapia (Tilapia mossambica) Obtained from Wet Markets and Ponds in Penang, Malaysia.

    Science.gov (United States)

    Budiati, Titik; Rusul, Gulam; Wan-Abdullah, Wan Nadiah; Chuah, Li-Oon; Ahmad, Rosma; Thong, Kwai Lin

    2016-04-01

    A total of 43 Salmonella enterica isolates belonging to different serovars (Salmonella Albany, Salmonella Agona, Salmonella Corvallis, Salmonella Stanley, Salmonella Typhimurium, Salmonella Mikawasima, and Salmonella Bovismorbificans) were isolated from catfish (Clarias gariepinus) and tilapia (Tilapia mossambica) obtained from nine wet markets and eight ponds in Penang, Malaysia. Thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, respectively. Fish reared in ponds were fed chicken offal, spoiled eggs, and commercial fish feed. The genetic relatedness of these Salmonella isolates was determined by random amplified polymorphic DNA PCR (RAPD-PCR) using primer OPC2, repetitive extragenic palindromic PCR (REP-PCR), and pulsed-field gel electrophoresis (PFGE). Composite analysis of the RAPD-PCR, REP-PCR, and PFGE results showed that the Salmonella serovars could be differentiated into six clusters and 15 singletons. RAPD-PCR differentiated the Salmonella isolates into 11 clusters and 10 singletons, while REP-PCR differentiated them into 4 clusters and 1 singleton. PFGE differentiated the Salmonella isolates into seven clusters and seven singletons. The close genetic relationship of Salmonella isolates from catfish or tilapia obtained from different ponds, irrespective of the type of feed given, may be caused by several factors, such as the quality of the water, density of fish, and size of ponds.

  18. Protozoan and metazoan parasites of Nile tilapia Oreochromis niloticus cultured in Brazil

    Directory of Open Access Journals (Sweden)

    Wanderson Pantoja MF

    2012-04-01

    Full Text Available Objective. This study describes the parasitic fauna and relative condition factor (Kn in Nile tilapia Oreochromis niloticus L. (Cichlidae from fish farms in the State of Amapá. Material and methods. 123 fish from four fish farms in the state of Amapá, Brazil were necropsied for parasitological and Kn analysis. Results. 64.2% of the examined fish, had the gills infected with Cichlidogyrus tilapiae Paperna, 1960 (Monogenoidea: Dactylogyridae; Ichthyophthirius multifiliis Fouquet, 1876 (Protozoa: Ciliophora, Trichodina Ehrenberg, 1830 and Paratrichodina africana Kazubski & El-Tantawy, 1986 (Protozoa: Trichodinidae. The highest prevalence found corresponded to Monogenoidea C. tilapiae while the lowest corresponded to Trichodinidae. However, I. multifiliis was the parasite that presented the greatest intensity and abundance. The differences found in the infection rates of the different fish farms due to causes further discussed. The parasitism did not influence the relative condition factor (Kn of fish. This was the first record of P. africana in Brazil and occurred in the Eastern Amazon. Conclusions. In Brazil, Lamproglena sp. is an emerging parasite in the Southern and Southeastern regions, but this crustacean was not found in the Nile tilapia in the State of Amapá. The parasitic infections in Nile tilapia farmed in Brazil are caused by protozoan, monogenoidea, crustacea and digenea species, and the regional differences on their prevalence and intensity rates are discussed in this study.

  19. Capsule impairs efficient adherence of Streptococcus agalactiae to intestinal epithelium in tilapias Oreochromis sp.

    Science.gov (United States)

    Barato, P; Martins, E R; Vasquez, G M; Ramirez, M; Melo-Cristino, J; Martínez, N; Iregui, C

    2016-11-01

    Streptococcosis caused by Streptococcus agalactiae is one of the most important diseases in the tilapia aquaculture industry. The role of the capsule of Streptococcus agalactiae in adherence to fish surfaces has not been evaluated and the mechanism of capsular regulation during adhesion has not been described. The aim of this study was to evaluate the role of the capsule of S. agalactiae during adhesion to intestinal epithelium of tilapia (Oreochromis sp.) in an ex vivo infection model. We show that the capsule impairs the adhesion of bacteria to host intestinal epithelium. Wild type (WT) strain SaTiBe08-18 (S. agalactiae recovered from tilapia) had reduced adhesion (P S. agalactiae to tilapia intestine and that the acidic milieu could regulate adherence of encapsulated strains. We found GlcNAc on the surface of adherent Δcps but not over the capsule in WT. This difference could be explained by the GlcNAc composition of Lancefield group B antigen and the peptidoglycan in GBS (Group B Streptococcus) and also may be related with better exposure of glycosylated adhesins in unencapsulated fish GBS. Understanding capsular regulation during adhesion of S. agalactiae may provide new leads to find a successful anti-adherence therapy to prevent streptococcosis in tilapia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Meningoencephalitis in farmed monosex Nile tilapia (Oreochromis niloticus L. caused by Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    Adikesavalu Harresh

    2017-09-01

    Full Text Available Aquaculture of tilapia is a new research venture in India. With intensification in farming practices, tilapia are increasingly susceptible to bacterial infections. This article describes the isolation and identification of pathogenic bacteria from cultured monosex Nile tilapia, Oreochromis niloticus (L., that experienced moderate to severe mortalities in West Bengal, India between September and August 2014 and histopathological alterations in various organs. Gram-positive diplococci, identified as Streptococcus agalactiae with Streptococcus identification kits and 16S rDNA sequencing analysis, were isolated from the brain, operculum, and kidney. Other bacteria from the kidney were identified as Aeromonas sobria, A. caviae, Klebsiella pneumoniae ssp. pneumoniae, Escherichia coli, and Enterobacter cloacae. Staphylococcus epidermis was isolated from opercular hemorrhages. Histological sections of the infected tilapia brain revealed meningoencephalitis and granulomatous lesions. Sections from other organs indicated congestion, hemorrhagic and hyperplastic cells, necrosis, vacuolation, hemosiderin deposition, hypertrophic nuclei, melanomacrophage aggregation, and ruptured veins. This report is the first description of S. agalactiae as a primary pathogen causing meningoencephalitis in cultured tilapia in India.

  1. Cloning and characterization of the gene for L-amino acid oxidase in hybrid tilapia.

    Science.gov (United States)

    Shen, Yubang; Fu, Gui Hong; Liu, Feng; Yue, Gen Hua

    2015-12-01

    Tilapia is the common name for a group of cichlid fishes. Identification of DNA markers significantly associated with important traits in candidate genes may speed up genetic improvement. L-Amino acid oxidase (LAO) plays a crucial role in the innate immune defences of animals. Previously, whether LAO variants were associated with economic traits had not been studied in fish. We characterized the cDNA sequence of the LAO gene of hybrid tilapia (Oreochromis spp.). Its ORF was 1536 bp, encoding a flavoenzyme of 511 amino acids. This gene consisted of seven exons and six introns. Its expression was detected in the intestine, blood, kidney, skin, liver. It was highly expressed in the intestine. After a challenge with a bacterial pathogen, Streptococcus agalactiae, its expression was up-regulated significantly in the liver, intestine and spleen (P tilapia. The investigation of relationship between polymorphism of LAO gene and disease resistance and growth in tilapia showed that one SNP was associated significantly with body length. Further experiments on whether SNPs in the LAO gene are associated with growth in tilapia and other populations could be useful in understanding more functions of the LAO gene.

  2. First identification of Francisella noatunensis subsp. orientalis causing mortality in Mexican tilapia Oreochromis spp.

    Science.gov (United States)

    Ortega, Cesar; Mancera, Gerardo; Enríquez, Ricardo; Vargas, Augusto; Martínez, Simón; Fajardo, Raúl; Avendaño-Herrera, Ruben; Navarrete, María José; Romero, Alex

    2016-08-09

    Francisellosis, an emerging disease in tilapia Oreochromis spp., is caused by the facultative, intracellular bacterium Francisella noatunensis subsp. orientalis, which is present in various countries where tilapia farming is commercially important. We confirmed the presence of francisellosis in Mexican tilapia cultures in association with an outbreak during the second semester of 2012. Broodstock fish presented a mortality rate of approximately 40%, and disease was characterized by histologically classified granulomas, or whitish nodules, in different organs, mainly the spleen and kidney. Through DNA obtained from infected tissue and pure cultures in a cysteine heart medium supplemented with hemoglobin, F. noatunensis subsp. orientalis was initially confirmed through the amplification and analysis of the 16S rRNA gene and the internal transcribed spacer region. Phylogenetic analysis of these genes demonstrated close similarity with previously reported F. noatunensis subsp. orientalis sequences obtained from infected tilapia from various countries. The identification of this subspecies as the causative agent of the outbreak was confirmed using the iglC gene as a target sequence, which showed 99.5% identity to 2 F. noatunensis subsp. orientalis strains (Ethime-1 and Toba04). These findings represent the first documented occurrence of francisellosis in Mexican tilapia cultures, which highlights the importance of establishing preventative measures to minimize the spread of this disease within the Mexican aquaculture industry.

  3. Chemometrics applied to the incorporation of omega-3 in tilapia fillet feed flaxseed flour

    Directory of Open Access Journals (Sweden)

    Márcia Fernandes Nishiyama

    2014-09-01

    Full Text Available This study evaluated the effect of adding flaxseed flour to the diet of Nile tilapia on the fatty acid composition of fillets using chemometrics. A traditional and an experimental diet containing flaxseed flour were used to feed the fish for 60 days. An increase of 18:3 n-3 and 22:6 n-3 and a decrease of 18:2 n-6 were observed in the tilapia fillets fed the experimental diet. There was a reduction in the n-6:n-3 ratio. A period of 45 days of incorporation caused a significant change in tilapia chemical composition. Principal Component Analysis showed that the time periods of 45 and 60 days positively contributed to the total content of n-3, LNA, and DHA, highlighting the effect of omega-3 incorporation in the treatment containing flaxseed flour.

  4. Experimental early pathogenesis of Streptococcus agalactiae infection in red tilapia Oreochromis spp.

    Science.gov (United States)

    Iregui, C A; Comas, J; Vásquez, G M; Verján, N

    2016-02-01

    Streptococcus agalactiae causes a severe systemic disease in fish, and the routes of entry are still ill-defined. To address this issue, two groups of 33 red tilapia Oreochromis spp. each of 10 g were orally infected with S. agalactiae (n = 30), and by immersion (n = 30), six individuals were control-uninfected fish. Three tilapias were killed at each time point from 30 min to 96 h post-inoculation (pi); controls were killed at 96 h. Samples from most tissues were examined by haematoxylin-eosin (H&E), indirect immunoperoxidase (IPI) and periodic acid-Schiff; only intestine from fish infected by gavage was evaluated by transmission electron microscopy. The results of both experiments suggest that the main entry site of S. agalactiae in tilapia is the gastrointestinal epithelium; mucus seems to play an important defensive role, and environmental conditions may be an important predisposing factor for the infection. © 2015 John Wiley & Sons Ltd.

  5. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    Science.gov (United States)

    Sockalingam, K.; Abdullah, H. Z.

    2015-07-01

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties.

  6. Research findings from the use of probiotics in tilapia aquaculture: A review.

    Science.gov (United States)

    Hai, Ngo Van

    2015-08-01

    This study aims to present research findings from the use of probiotics in tilapia aquaculture. In omnivorous species of tilapia aquaculture, intestines and gonads, rearing water and sediments or even commercial products, can be sources for acquiring appropriate probiotics. Administration of probiotics varies from direct oral/water routine to feed additives, of which the latter is most commonly used. Probiotic applications can be either mono or multiple strains. Dosage and duration of time are significant factors in providing desired results. As probiotics have been proven to be either immune enhancers and/or growth promoters in aquatic animals, several modes of actions of probiotics in enhancement of immune responses, and an improvement of growth and survival rates of tilapia are presented, while the effects of others are not yet understood to the same degree as for other fish species. Some points extracted from the research findings are emphasised for further investigation and development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    Energy Technology Data Exchange (ETDEWEB)

    Sockalingam, K., E-mail: gd130106@siswa.uthm.edu.my; Abdullah, H. Z., E-mail: hasan@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties.

  8. APPARENT DIGESTIBILTY EXPERIMENT WITH NILE TILAPIA (OREOCHROMIS NILOTICUS FED DIETS CONTAINING CITRULLUS LANATUS SEEDMEAL

    Directory of Open Access Journals (Sweden)

    Wasiu Adeyemi JIMOH

    2015-12-01

    Full Text Available Apparent digestibility coefficients of nutrients in Citrullus lanatus based diets were determined for Nile tilapia (Oreochromis niloticus using AIA as marker or indicator. 150 tilapia fingerlings of average weight 6.12±0.05g were acclimatized for a week, weighed and allotted into five dietary treatments; CTR, DT2, DT3, DT4 and DT5 containing 0, 15, 30, 45 and 60% Citrullus lanatus respectively. The diets were isonitrogenous, isocaloric and isolipidic. Each treatment was replicated three times with ten fish per replicate. Fish were fed 5% body weight on two equal proportions per day. The results from the study indicated that there was no significant variation (p>0.05 in the apparent organic matter and gross energy digestibility coefficients of the diets; that there was significant (p0.05 in the apparent digestibility coefficients of nutrients (protein, energy, lipid and carbohydrates between the diets up to 30% replacement levels for tilapia.

  9. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    International Nuclear Information System (INIS)

    Sockalingam, K.; Abdullah, H. Z.

    2015-01-01

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties

  10. Circular DNA Intermediate in the Duplication of Nile Tilapia vasa Genes

    Science.gov (United States)

    Fujimura, Koji; Conte, Matthew A.; Kocher, Thomas D.

    2011-01-01

    vasa is a highly conserved RNA helicase involved in animal germ cell development. Among vertebrate species, it is typically present as a single copy per genome. Here we report the isolation and sequencing of BAC clones for Nile tilapia vasa genes. Contrary to a previous report that Nile tilapia have a single copy of the vasa gene, we find evidence for at least three vasa gene loci. The vasa gene locus was duplicated from the original site and integrated into two distant novel sites. For one of these insertions we find evidence that the duplication was mediated by a circular DNA intermediate. This mechanism of gene duplication may explain the origin of isolated gene duplicates during the evolution of fish genomes. These data provide a foundation for studying the role of multiple vasa genes in the development of tilapia gonads, and will contribute to investigations of the molecular mechanisms of sex determination and evolution in cichlid fishes. PMID:22216289

  11. The osmoregulatory effects of rearing Mozambique tilapia in a tidally changing salinity.

    Science.gov (United States)

    Moorman, Benjamin P; Inokuchi, Mayu; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

    2014-10-01

    The native distribution of Mozambique tilapia, Oreochromis mossambicus, is characterized by estuarine areas subject to salinity variations between fresh water (FW) and seawater (SW) with tidal frequency. Osmoregulation in the face of changing environmental salinity is largely mediated through the neuroendocrine system and involves the activation of ion uptake and extrusion mechanisms in osmoregulatory tissues. We compared plasma osmolality, plasma prolactin (PRL), pituitary PRL mRNA, and mRNA of branchial ion pumps, transporters, channels, and PRL receptors in tilapia reared in FW, SW, brackish water (BW) and in tidally-changing salinity, which varied between FW (TF) and SW (TS) every 6h. Plasma PRL was higher in FW tilapia than in SW, BW, TF, and TS tilapia. Unlike tilapia reared in FW or SW, fish in salinities that varied tidally showed no correlation between plasma osmolality and PRL. In FW fish, gene expression of PRL receptor 1 (PRLR1), Na(+)/Cl(-) cotransporter (NCC), aquaporin 3 (AQP3) and two isoforms of Na(+)/K(+)-ATPase (NKA α1a and NKA α1b) was higher than that of SW, BW or tidally-changing salinity fish. Gene expression of the Na(+)/K(+)/2Cl(-) cotransporter (NKCC1a), and the cystic fibrosis transmembrane conductance regulator (CFTR) were higher in fish in SW, BW or a tidally-changing salinity than in FW fish. Immunocytochemistry revealed that ionocytes of fish in tidally-changing salinities resemble ionocytes of SW fish. This study indicated that tilapia reared in a tidally-changing salinity can compensate for large changes in external osmolality while maintaining osmoregulatory parameters within a narrow range closer to that observed in SW-acclimated fish. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Environmental and cortisol-mediated control of Ca(2+) uptake in tilapia (Oreochromis mossambicus).

    Science.gov (United States)

    Lin, Chia-Hao; Kuan, Wei-Chun; Liao, Bo-Kai; Deng, Ang-Ni; Tseng, Deng-Yu; Hwang, Pung-Pung

    2016-04-01

    Ca(2+) is a vital element for many physiological processes in vertebrates, including teleosts, which live in aquatic environments and acquire Ca(2+) from their surroundings. Ionocytes within the adult gills or larval skin are critical sites for transcellular Ca(2+) uptake in teleosts. The ionocytes of zebrafish were found to contain transcellular Ca(2+) transporters, epithelial Ca(2+) channel (ECaC), plasma membrane Ca(2+)-ATPase 2 (PMCA2), and Na(+)/Ca(2+) exchanger 1b (NCX1b), providing information about the molecular mechanism of transcellular Ca(2+) transports mediated by ionocytes in fish. However, more evidence is required to establish whether or not a similar mechanism of transcellular Ca(2+) transport also exists in others teleosts. In the present study, ecac, pmca2, and ncx1 were found to be expressed in the branchial ionocytes of tilapia, thereby providing further support for the mechanism of transcellular Ca(2+) transport through ionocytes previously proposed for zebrafish. In addition, we also reveal that low Ca(2+) water treatment of tilapia stimulates Ca(2+) uptake and expression of ecac and cyp11b (the latter encodes a cortisol-synthesis enzyme). Treatment of tilapia with exogenous cortisol (20 mg/l) enhanced both Ca(2+) influx and ecac expression. Therefore, increased cyp11b expression is suggested to enhance Ca(2+) uptake capacity in tilapia exposed to low Ca(2+) water. Furthermore, the application of cortisol receptor antagonists revealed that cortisol may regulate Ca(2+) uptake through glucocorticoid and/or mineralocorticoid receptor (GR and/or MR) in tilapia. Taken together, the data suggest that cortisol may activate GR and/or MR to execute its hypercalcemic action by stimulating ecac expression in tilapia.

  13. FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

    OpenAIRE

    EDUARDO ARRUDA TEIXEIRA LANNA; MARCOS ANTONIO DELMONDES BOMFIM; FELIPE BARBOSA RIBEIRO; MOISÉS QUADROS

    2016-01-01

    The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus) fed low-protein diets (29% crude protein) supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine). Sex-reversed Nile tilapia (240) of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day). Six replications were conducted on separate exper...

  14. FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

    OpenAIRE

    LANNA, EDUARDO ARRUDA TEIXEIRA; BOMFIM, MARCOS ANTONIO DELMONDES; RIBEIRO, FELIPE BARBOSA; QUADROS, MOISÉS

    2016-01-01

    ABSTRACT: The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus) fed low-protein diets (29% crude protein) supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine). Sex-reversed Nile tilapia (240) of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day). Six replications were conducted on sepa...

  15. Bacteriological Quality of Tilapia Fish from Treated Wastewater in Peri-Urban Areas, Morogoro, Tanzania

    DEFF Research Database (Denmark)

    Mhongole, OJ; Mdegela, RH; Kusiluka, LJM

    2016-01-01

    the inlet to outlet of Mzumbe wastewater treatment pond, there was a significant reduction (pquality for human consumption based......The aim of this study was to assess faecal bacterial contamination in tilapia fish from wastewater treatment ponds at Mzumbe and in pristine water in Mindu dam. Tilapia fish (fish flesh and fish intestines) and water samples were analysed for Escherichia coli and total plate count....... The concentration of E. coli in fish intestines ranged from about 1 - 3.5 log cfu/g and water in Mindu dam ranged from 0 to 15 cfu/mL. From...

  16. Salmonella Weltevreden in integrated and non-integrated tilapia aquaculture systems in Guangdong, China

    DEFF Research Database (Denmark)

    Li, Kang; Petersen, Gitte; Barco, Lisa

    2017-01-01

    including transmission of faecal zoonotic pathogens and accumulation of antimicrobial and other chemical residues. This study aimed to determine differences in occurrence and characteristics of Salmonella spp. isolated from tilapia-pig and non-integrated aquaculture systems in Guangdong province, China...... method showed a clonal relationship of S. Weltevreden which was supported by similar antimicrobial resistance patterns (sulfamethoxazole and trimethoprim resistance) as well as most isolates harbouring a 147-kb sized plasmid. The common finding of S. Weltevreden in both tilapia production systems...

  17. Blue tilapia (Oreochromis aureus) predation on fishes in the Muddy River system, Clark County, Nevada

    Science.gov (United States)

    Scoppettone, G.G.; Salgado, J.A.; Nielsen, M.B.

    2005-01-01

    Blue tilapia (Oreochromis aureus), native to North Africa and the Middle East (Courtenay and Robins 1973, Fuller et al. 1999), has been introduced around the world as a human food source, for vegetation control, and as a game fish (Costa-Pierce and Riedel 2000). Blue tilapia has been particularly successful in establishing and spreading in North American waters where it has been reported to change fish community structure and cause native fish decline (Courtenay and Robins 1973, Fuller et al. 1999). Because of these detrimental effects, it is now generally considered an unwelcome introduction into North American waters (Dill and Cordone 1997, Fuller et al. 1999).

  18. Tilapia-waste flour as a natural nutritional replacer for bread: A consumer perspective.

    Science.gov (United States)

    Monteiro, Maria Lúcia G; Mársico, Eliane T; Soares Junior, Manoel S; Deliza, Rosires; de Oliveira, Denize C R; Conte-Junior, Carlos A

    2018-01-01

    Six bread formulations with different levels of tilapia-waste flour (BTF0%, BTF2.5%, BTF5%, BTF10%, BTF15%, and BTF20%) were analyzed for nutritional composition and sensory characterization. Tilapia-waste flour (TF) increased (P bread at levels below 12.17% (P bread because of a disagreeable flavor, aroma, and texture; however, airy appearance, sticky in the teeth and cream color did not influence the overall liking. TF at 5% enhanced the nutritional value while maintaining acceptable sensory scores for bread, constituting a potential strategy to satisfy consumer and industry requirements.

  19. Nile tilapia culture on domestic effluent treated in stabilization ponds.

    Directory of Open Access Journals (Sweden)

    Clovis Matheus Pereira

    2009-03-01

    Full Text Available The performance and filet quality of tilapias (Oreochromis niloticus culture in effluent stabilization lagoons was tested at the densities of 3 fish/m2 (T3, 7 fish/m2 (T2 and 7 fish/m2 in clean water + diet (T1 with 3 repetitions in tanks of 2.57m2 and 0.60m of water column with supplemental aeration. Fish culture in clean water plus diet (T1 presented the highest growth. The higher density T3 (7/m2 compared to T2 (3/m2 did not result in any difference of total production (p > 0.05 but this was compensated by the increased individual fish growth rate at lower density. The conditions that sustain fish survival culture with ETE effluent were attested by the high survival (> 90% under both treatments, but only 10% of the water samples from T2 and T3 N-total ammonium was favorable for fish growth (< 2.0mg/L. The rearing system improved the effluent quality, reducing the total organic nitrogen and the solids in suspension. The faecal coliforms, Salmonella sp. and Staphylococcus aureus from the effluent and fish were verified to be within the standards laid down by the World Health Organization (WHO.

  20. Microbial quality of tilapia reared in fecal-contaminated ponds

    International Nuclear Information System (INIS)

    El-Shafai, S.A.; Gijzen, H.J.; Nasr, F.A.; El-Gohary, F.A.

    2004-01-01

    The microbial quality of tilapia reared in four fecal-contaminated fishponds was investigated. One of the fishponds (TDP) received treated sewage with an average fecal coliform count of 4x10 3 cfu/100 mL, and feed of fresh duckweed grown on treated sewage was used. The number of fecal coliform bacteria attached to duckweed biomass ranged between 4.1x10 2 and 1.6x10 4 cfu/g fresh weight. The second fishpond (TWP) received treated sewage, and the feed used was wheat bran. The third fishpond (FDP) received freshwater, and the feed used was the same duckweed. Pond 4 (SSP) received only settled sewage with an average fecal coliform count of 2.1x10 8 /100 mL. The average counts in the fishponds were 2.2x10 3 , 1.7x10 3 , 1.7x10 2 , and 9.4x10 3 cfu/100 mL in TDP, TWP, FDP, and SSP, respectively. FDP had a significantly (P gills>skin>liver. Poor water quality (ammonia and nitrite) in SSP resulted in statistically higher fecal coliform numbers in fish organs of about 1 log 10 than in treatments with good water quality. Pretreatment of sewage is therefore recommended

  1. Streptococcus agalactiae isolates of serotypes Ia, III and V from human and cow are able to infect tilapia.

    Science.gov (United States)

    Chen, Ming; Wang, Rui; Luo, Fu-Guang; Huang, Yan; Liang, Wan-Wen; Huang, Ting; Lei, Ai-Ying; Gan, Xi; Li, Li-Ping

    2015-10-22

    Recent studies have shown that group B streptococcus (GBS) may be infectious across hosts. The purpose of this study is to investigate the pathogenicity of clinical GBS isolates with serotypes Ia, III and V from human and cow to tilapia and the evolutionary relationship among these GBS strains of different sources. A total of 27 clinical GBS isolates from human (n=10), cow (n=2) and tilapia (n=15) were analyzed using serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Among them, 15 isolates were tested for their pathogenicity to tilapia. The results showed that five human GBS strains (2 serotype III, 2 serotype Ia and 1 serotype V) infected tilapia with mortality rate ranging from 56.67% to 100%, while the other five human GBS strains tested were unable to infect tilapia. In addition, two cow GBS strains C001 and C003 of serotype III infected tilapia. However, they had significantly lower pathogenicity than the five human strains. Furthermore, human GBS strains H005 and H008, which had very strong ability to infect tilapia, had the same PFGE pattern. MLST analysis showed that the five human and the two cow GBS strains that were able to infect tilapia belonged to clonal complexes CC19, CC23 and CC103. The study for the first time confirmed that human or cow GBS clonal complexes CC19, CC23 and CC103 containing strains with serotypes Ia, III and V could infect tilapia and induce clinical signs under experimental conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Dietary phosphatidylcholine impacts on growth performance and lipid metabolism in adult Genetically Improved Farmed Tilapia (GIFT) strain of Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Tian, Juan; Wen, Hua; Lu, Xing; Liu, Wei; Wu, Fan; Yang, Chang-Geng; Jiang, Ming; Yu, Li-Juan

    2018-01-01

    This study aimed to determine the effects of supplementing the diet of adult Nile tilapia Oreochromis niloticus with phosphatidylcholine (PC) on growth performance, body composition, fatty acid composition and gene expression. Genetically Improved Farmed Tilapia fish with an initial body weight of 83·1 (sd 2·9) g were divided into six groups. Each group was hand-fed a semi-purified diet containing 1·7 (control diet), 4·0, 6·5, 11·5, 21·3 or 41·0 g PC/kg diet for 68 d. Supplemental PC improved the feed efficiency rate, which was highest in the 11·5 g PC/kg diet. Weight gain and specific growth rate were unaffected. Dietary PC increased PC content in the liver and decreased crude fat content in the liver, viscera and body. SFA and MUFA increased and PUFA decreased in muscle with increasing dietary PC. Cytoplasmic phospholipase A 2 and secreted phospholipase A 2 mRNA expression were up-regulated in the brain and heart in PC-supplemented fish. PC reduced fatty acid synthase mRNA expression in the liver and visceral tissue but increased expression in muscle. Hormone-sensitive lipase and lipoprotein lipase expression increased in the liver with increasing dietary PC. Growth hormone mRNA expression was reduced in the brain and insulin-like growth factor-1 mRNA expression in liver reduced with PC above 6·5 g/kg. Our results demonstrate that dietary supplementation with PC improves feed efficiency and reduces liver fat in adult Nile tilapia, without increasing weight gain, representing a novel dietary approach to reduce feed requirements and improve the health of Nile tilapia.

  3. Genotype by production environment interaction in the GIFT strain of Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Khaw, H.L.; Ponzonia, R.W.; Hamzah, A.; Abu-Bakara, K.R.; Bijma, P.

    2012-01-01

    Three discrete generations of GIFT fish (Nile tilapia strain, Oreochromis niloticus; a total of 10,065 fish with pedigree and phenotypic information) were tested in pond and cage culture environments to determine genotype by production environment interaction between both environments in Malaysia.

  4. Oxidative stress responses in gills of tilapia (Oreochromis niloticus) at different salinities

    Science.gov (United States)

    Handayani, Kiki Syaputri; Novianty, Zahra; Saputri, Miftahul Rohmah; Irawan, Bambang; Soegianto, Agoes

    2017-08-01

    The objective of present study is to evaluate the impact of different salinities on the levels of CAT, GSH and MDA of the gills of Nile tilapia (Oreochromis niloticus). Nile tilapia was treated by exposure to salinities concentration 0 ‰, 5 ‰ and 10 ‰. Research models were weakened and sacrificed, then took the left and right sides of the gills. The result of gills homogenity was centrifuged for supernatan, then supernatan was proceed with testing levels of CAT, GSH and MDA by ELISA assay methods. The levels of CAT in gills were significantly higher at 10 ‰ than at 5 ‰ and 0 ‰. The levels of GSH in gills were significantly higher at 0 ‰ than 5 ‰. The levels of GSH in gills at 5 ‰ and 10 ‰ salinities were not significantly different. The levels of MDA in gills at salinity 10 ‰ and 5 ‰ were higher than in control gills at 0 ‰ salinities. This occurs because the salinity of 10 ‰ salinity was optimal for live of fish tilapia. In conclusion, salinity impact the increasing of CAT, GSH, and MDA levels in gills of Nile tilapia.

  5. Daily growth of young-of-the-year of the Baringo tilapia ...

    African Journals Online (AJOL)

    Otolith microstructure analysis was used to validate microincrement deposition rate and to determine daily growth rates of young-of-the-year (YOY) Baringo tilapia, Oreochromis niloticus baringoensis. Microincrement formation was validated as daily by correlating the number of circuli on otoliths with the known age of ...

  6. Influence of glyceryl guaiacolate ether on anesthetics in tilapia compared to benzocaine and eugenol

    Directory of Open Access Journals (Sweden)

    Geovana R. Cosenza

    2014-03-01

    Full Text Available Objective. The study aimed to investigate the effectiveness of glyceryl guaiacolate ether (GGE and compare the times of induction, recovery, hematological changes, total protein and glycaemia among anesthetics in Nile tilapia, Oreochromis niloticus. Materials and methods. A total of 60 tilapia distributed in 3 aquariums (N=20 were used, which formed the group benzocaine (100 mg/L, eugenol (50 mg/L and guaiacol glyceryl ether (9.000 mg/L. After the induction of anesthesia fish blood samples were collected to determine the complete hemogram and glycemia. Then the animals were placed in aquariums with running water for assessing the anesthesia recovery. Results. It was verified that GGE showed longer induction and recovery times as well a significant increase (p0.05. An increase in the number of monocytes in the group treated with benzocaine (p <0.05 was observed in the analysis of the hematological parameters with no difference between groups for other variables. Conclusions. Eugenol and benzocaine allow rapid induction and recovery in Nile tilapia, without evidence of stress during handling and GGE showed high induction and recovery times, being inadequate for anesthetic use in Nile tilapia.

  7. Beta-haemolytic streptococci in farmed Nile tilapia, Oreochromis niloticus, from Sullana-Piura, Peru

    Directory of Open Access Journals (Sweden)

    Yessica Ortega A

    2017-01-01

    Full Text Available Objective. This investigation aimed to study the presence of Streptococcus spp. in tilapia (Oreochromis niloticus from fish farm located in Sullana-Piura, Peru. Materials and methods. 150 fish with clinical signs of streptococcal disease were sampled, and the bacterium isolation was performed on blood agar, correlated to histopathological lesions description and molecular confirmation by real-time PCR. Results. The necropsy revealed exophthalmia, hyphema, congestion and/or haemorrhagic meninges, ascites, splenomegaly, hepatomegaly and diffuse haemorrhagic zones throughout the body. 102 isolated positives (54 tilapias to Streptococcus spp. were identified in the microbiological analysis (prevalence of 26%, the brain was the organ with the highest percentage of this bacteria (34.31%, and 19 isolates were beta-haemolytic (18.63% with prevalence of 10.12%. Fish beta-haemolytic streptococci presented epicarditis, perisplenitis and chronic meningitis, panophthalmitis, coagulative necrosis of skeletal muscle and granulomas formation. In the confirmatory test by real-time PCR, any positive tilapia to S. iniae was obtained. The results were analysed using a stochastic simulation of beta distribution using @Risk program uncertainty, reporting an average prevalence of 0.66% in sick tilapias. Conclusions. The analysed fishes were positive to bacteria of the genus Streptococcus, which confirms its presence in the fish farm. However, 19 isolates were beta-haemolytic, and the presence of S. iniae was not positive to the limit prevalence of 2.7% in real-time PCR.

  8. Bioaccumulation of some heavy metals in tilapia fish relevant to their ...

    African Journals Online (AJOL)

    Concentrations of some heavy metals (Pb, Cd, Hg, Cu and Cr) were determined in water, sediment and tissues of tilapia fish collected from Wadi Hanifah during summer 2010. The concentrations of the heavy metal in water were within the international permissible level. Cu had the highest accumulating level in fish whilst ...

  9. beta-adrenoceptors mediate inhibition of lipolysis in adipocytes of tilapia (Oreochromis mossambicus)

    NARCIS (Netherlands)

    Vianen, GJ; Obels, PP; Van Den Thillart, GEEJM; Zaagsma, J

    The regulation of triglyceride mobilization by catecholamines was investigated in the teleost fish Oreochromis mossambicus (tilapia) in vivo and in vitro. In vitro experiments were carried out with adipocytes that were isolated for the first time from fish adipose tissue. For the in vivo

  10. Genetic parameters for reproductive traits in female Nile tilapia (Oreochromis niloticus): II. Fecundity and fertility

    NARCIS (Netherlands)

    Trong, T.Q.; Arendonk, van J.A.M.; Komen, J.

    2013-01-01

    Harvest weight is the main trait in Nile tilapia (Oreochromis niloticus) breeding programmes. The effects of selection for harvest weight on female reproductive traits are unknown. In this paper we estimate genetic parameters for reproductive traits and their correlation with harvest weight using

  11. Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    EI-Shafail, S A; Nasrl, F A; EI-Gohary, F.A. A. [Water Pollution Control Department, National Research Centre, Dokki, Giza (Egypt); Cijzen, H J; Steen, N P [Environmental Resources Department, UNESCO-IHE Institute, Delft (Netherlands)

    2004-07-01

    Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p < 0.01) higher than the SGR in wheat bran fed pond. No significant difference (p > 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality.

  12. Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus)

    International Nuclear Information System (INIS)

    Zhou, Linyan; Luo, Feng; Fang, Xuelian; Charkraborty, Tapas; Wu, Limin; Wei, Jing; Wang, Deshou

    2016-01-01

    Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish. - Highlights: • DHP plays a critical role in early stage oogenesis of XX tilapia. • Blockage of DHP actions by RU486 treatment led to masculinization and/or sex reversal in XX tilapia. • Both DHP and estrogen are indispensable for ovarian differentiation.

  13. Physicochemical and sensory characteristics of snack made with minced Nile tilapia

    Directory of Open Access Journals (Sweden)

    João De Paula Cortez Netto

    2014-09-01

    Full Text Available Nile tilapia is one of the major fish species cultivated worldwide and in Brazil. The tilapia fillet yield is between 30-35%, thus around 70% of waste is generated. A portion of this waste can be used to obtain minced fish, and the resulting product can be used as meat raw material to prepare fish snacks. The aim of this study was to produce fish snacks containing different inclusion levels (20, 30, and 40% of minced fish obtained from Nile tilapia processing waste and evaluate their physicochemical characteristics and sensory acceptance. Protein content, ash, water activity, and hardness increased with increasing inclusion of minced fish. The scores obtained in the sensory evaluation were: flavor acceptance (from 7.2 to 5.7, texture (from 7.4 to 5.3, overall acceptance (from 7.1 to 5.9, and willingness to purchase (from 4.0 to 3.1. This study demonstrates that the inclusion of 20 to 40% of minced fish of Nile tilapia in snacks is well accepted and improves their nutritional value without affecting the physicochemical properties.

  14. Genetic parameters for fillet traits and body measurements in Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    Rutten, M.J.M.; Bovenhuis, H.; Komen, J.

    2005-01-01

    Fillet weight is an economically important trait in Nile tilapia production for the European market which asks for fish with average body weights of at least 700 g. Genetic parameters to design or optimize breeding programs for these body weights are lacking. In an earlier study we showed that high

  15. Complete genome sequence of a virulent Streptococcus agalactiae strain 138P isolated from diseased Nile tilapia

    Science.gov (United States)

    Streptococcus agalactiae strain 138P was isolated from the kidney of diseased Nile tilapia in Idaho during a 2007 streptococcal disease outbreak. The full genome of S. agalactiae 138P is 1,838,716 bp. The availability of this genome will allow comparative genomics to identify genes for antigen disco...

  16. Application of Highly Purified Electrolyzed Chlorine Dioxide for Tilapia Fillet Disinfection

    Directory of Open Access Journals (Sweden)

    Chen-Hsing Yu

    2014-01-01

    Full Text Available This research aimed to develop an electrolysis method to generate high-concentration chlorine dioxide (ClO2 for tilapia fillet disinfection. The designed generator produced up to 3500 ppm of ClO2 at up to 99% purity. Tilapia fillets were soaked in a 400 ppm ClO2 solution for 5, 10, and 25 min. Results show that total plate counts of tilapia, respectively, decreased by 5.72 to 3.23, 2.10, and 1.09 log CFU/g. In addition, a 200 ppm ClO2 solution eliminated coliform bacteria and Escherichia coli in 5 min with shaking treatment. Furthermore, ClO2 and trihalomethanes (THMs residuals on tilapia fillets were analyzed by GC/MS and were nondetectable (GC-MS detection limit was 0.12 ppb. The results conform to Taiwan’s environmental protection regulations and act governing food sanitation.

  17. Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

    International Nuclear Information System (INIS)

    EI-Shafail, S.A.; Nasrl, F.A.; EI-Gohary, F.A. A.; Cijzen, H.J.; Steen, N.P.

    2004-01-01

    Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality

  18. Apparent digestibility coefficient of duckweed (Lemna minor), fresh and dry for Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    El-Shafai, S.A.A.M.; El-Gohary, F.; Verreth, J.A.J.; Schrama, J.W.; Gijzen, H.J.

    2004-01-01

    Dry matter (DMD), protein (PD), ash (AD), fat (FD), gross energy (ED) and phosphorus (PhD) digestibility coefficients were determined for five different iso-N fish diets fed to Nile tilapia (Oreochromis niloticus). The control diet contained fishmeal (35%), corn (29%), wheat (20%), wheat bran (10%),

  19. Quality properties, fatty acids, and biogenic amines profile of fresh tilapia stored in ice.

    Science.gov (United States)

    Kulawik, Piotr; Özoğul, Fatih; Glew, Robert H

    2013-07-01

    This work determines quality properties and fatty acids content of Nile tilapia (Oreochromis niloticus) stored in ice for 21 d. The quality properties consist of thiobarbituic acid (TBA), total volatile basic nitrogen (TVB-N), trimethylamine (TMA), and microbiological analysis (total viable count (TVC), total coliform, Salmonella and Staphylococcus aureus) and determination of biogenic amines content (histamine, cadaverine, putrescine, spermine, spermidine, 2-phenylethylamine, agmatine, tyramine, and ammonia). Moreover, the fat, moisture, and ash composition as well as fatty acids profile have also been analyzed. The TBA, TVB-N, and biogenic amines analysis showed rather low levels of spoilage even after 21 d of storage. The microbiological analysis, however, showed that tilapia was unsuitable for consumption after just 10 d. The fat, ash, moisture, and fatty acids profile analysis showed that tilapia is not a good source of n-3 fatty acids. The research indicated that the microbiological analysis was the best method to establish spoilage of tilapia stored in ice, of all analytical methods performed in this study. © 2013 Institute of Food Technologists®

  20. Effect of Salinity on the Survival and Growth of Rufiji Tilapia ...

    African Journals Online (AJOL)

    Abstract. Survival and growth of Rufiji tilapia (Oreochromis urolepis urolepis) fry were determined under controlled salinity conditions of 5, 15, 25 and 35 ppt for 56 days. Experiments were carried out in 12 concrete tanks of 1 m3 volume each with three replicates for each treatment. Data was recorded at fourteen days ...

  1. Productive performance of Nile tilapia (Oreochromis niloticus fed at different frequencies and periods with automatic dispenser

    Directory of Open Access Journals (Sweden)

    R.M.R. Sousa

    2012-02-01

    Full Text Available The performance of Nile tilapia (Oreochromis niloticus raised in cages furnished with an automatic dispenser, supplied at different frequencies (once per hour and once every two hours and periods (daytime, nighttime and both was evaluated. Eighteen 1.0m³ cages were placed into a 2000m² pond, two meters deep with a 5% water exchange. One hundred and seventy tilapias, with initial weight of 16.0±4.9g, were dispersed into each 1m³ cage and the feed ration was adjusted every 21 days with biometry. Data was collected from March to July (autumn and winter. Significant difference to final weight (P<0.05 among treatments was observed. The increase in feeding frequency improves the productive performance of Nile tilapias in cages and permitted better management of the food. The better feed conversion rate for high feeding frequency (24 times day-1 can result in saving up to 360kg of food for each ton of fish produced, increasing the economic sustenance for tilapia culture and suggesting less environmental pollution.

  2. Vegetable, livestock and agroindustrial products and byproducts: An alternative tilapia feeding

    Directory of Open Access Journals (Sweden)

    González Salas, R.

    2014-01-01

    Full Text Available In the culture of tilapia limited supply and high cost of fish meal have forced nutritionists to consider alternative sources of protein. Due to the importance of the products and by-products in fish feed, this paper aims to show the alternatives that have been used to partially or totally replace fish meal and soybean meal in tilapia growing. This paper showsthe maximum or optimal use of vegetable by-products for tilapia as cottonseed meal, sunflower, canola, soybean and Leucaena. It also deals with the inclusion with agro-industrial by-product such as corn, sorghum, coffee pulp, cocoa, wheat and citrus. The present study also deals with the use of aquatic plants such as Lemna and Azolla, single-celled plant protein source as antibiotics and probiotics. Finally, this paper also refers to animal by-products as silage, manure and earthworm usage. There is a high potential for using plant, livestock and agro-industrial by-products in fresh and processed food for the tilapia, but depending on the product, pretreatment to improve its balance of nutrients or eliminate anti-nutritional factors may be required.

  3. The effect of mercury on the growth efficiency of Tilapia mossambica (Peters)

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.; Qasim, S.Z.

    Three concentrations of mercury (0.01, 0.04 and 0.4 ppm) were used for experiments on growth efficiency of Tilapia mossambica. Growth efficiencies were determined on a dry weight basis. High concentration of mercury (0.4 ppm) caused considerable...

  4. Effect of some Nigerian spices on biodeterioration of tilapia and cat ...

    African Journals Online (AJOL)

    This research is in two phases, one phase investigated the use of spices to inhibit the quick deterioration of fish. Spices used ere Xylopia aethiopica, Capsicum frutescens, Zingiber officinale, Piper guineense. Fishes used were Clarias gariepinus and Tilapia guineensis. Blended spices were applied on the fishes and kept ...

  5. Attempted sterilization of sexually undifferentiated fry of Tilapia zillii by 60Co gamma-ray irradiation

    International Nuclear Information System (INIS)

    Nelson, S.G.; Andersen, A.C.; Momeni, M.H.; Yeo, R.R.

    1976-01-01

    Attempts to lessen the potential environmental hazards of aquatic vegetation control by use of weed eating exotic fish which have been sterilized is discussed. It was found that the gonads of Tilapia are very resistant to radiation and this method is thus not practical

  6. Development and evaluation of an intelligent traceability system for frozen tilapia fillet processing.

    Science.gov (United States)

    Xiao, Xinqing; Fu, Zetian; Qi, Lin; Mira, Trebar; Zhang, Xiaoshuan

    2015-10-01

    The main export varieties in China are brand-name, high-quality bred aquatic products. Among them, tilapia has become the most important and fast-growing species since extensive consumer markets in North America and Europe have evolved as a result of commodity prices, year-round availability and quality of fresh and frozen products. As the largest tilapia farming country, China has over one-third of its tilapia production devoted to further processing and meeting foreign market demand. Using by tilapia fillet processing, this paper introduces the efforts for developing and evaluating ITS-TF: an intelligent traceability system integrated with statistical process control (SPC) and fault tree analysis (FTA). Observations, literature review and expert questionnaires were used for system requirement and knowledge acquisition; scenario simulation was applied to evaluate and validate ITS-TF performance. The results show that traceability requirement is evolved from a firefighting model to a proactive model for enhancing process management capacity for food safety; ITS-TF transforms itself as an intelligent system to provide functions on early warnings and process management by integrated SPC and FTA. The valuable suggestion that automatic data acquisition and communication technology should be integrated into ITS-TF was achieved for further system optimization, perfection and performance improvement. © 2014 Society of Chemical Industry.

  7. Water cortisol and testosterone in Nile tilapia (Oreochromis niloticus) recirculating aquaculture systems

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    The accumulation of steroids released by fish in recirculating aquaculture systems (RAS) may potentially influence their physiology and behavior. The present study examined the release rate of cortisol and testosterone by Nile tilapia, Oreochromis niloticus, and their accumulation in six identical

  8. Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus)

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Linyan; Luo, Feng; Fang, Xuelian [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Charkraborty, Tapas [South Ehime Fisheries Research Center, Ehime University, Ainan, 798-4206 (Japan); Wu, Limin; Wei, Jing [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Wang, Deshou, E-mail: wdeshou@swu.edu.cn [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China)

    2016-04-22

    Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish. - Highlights: • DHP plays a critical role in early stage oogenesis of XX tilapia. • Blockage of DHP actions by RU486 treatment led to masculinization and/or sex reversal in XX tilapia. • Both DHP and estrogen are indispensable for ovarian differentiation.

  9. A humane protocol for electro-stunning and killing of Nile tilapia in fresh water

    NARCIS (Netherlands)

    Lambooij, E.; Gerritzen, M.A.; Reimert, H.G.M.; Burggraaf, D.; Vis, van de J.W.

    2008-01-01

    Behavioural, neural and physiological parameters were scored after electro-stunning of Nile tilapia (Oreochromis niloticus) in three positions to an electric field in fresh water. An overall current density, 1.0 Arms/dm2, 50 Hz sinusoidal, applied for 1 s top-to-bottom in water (700 ¿S/cm), induced

  10. Absorbed Dose Rate Due to Intake of Natural Radionuclides by Tilapia Fish (Tilapia nilotica,Linnaeus, 1758) Estimated Near Uranium Mining at Caetité, Bahia, Brazil

    Science.gov (United States)

    Pereira, Wagner de S.; Kelecom, Alphonse; Py Júnior, Delcy de Azevedo

    2008-08-01

    The uranium mining at Caetité (Uranium Concentrate Unit—URA) is in its operational phase. Aiming to estimate the radiological environmental impact of the URA, a monitoring program is underway. In order to preserve the biota of the deleterious effects from radiation and to act in a pro-active way as expected from a licensing body, the present work aims to use an environmental protection methodology based on the calculation of absorbed dose rate in biota. Thus, selected target organism was the Tilapia fish (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). As, in Brazil there are no radiation exposure limits adopted for biota the value proposed by the Department of Energy (DOE) of the United States of 3.5×103 μGy y-1 has been used. The derived absorbed dose rate calculated for Tilapia was 2.51×100 μGy y-1, that is less than 0.1% of the dose limit established by DOE. The critical radionuclide was Ra-226, with 56% of the absorbed dose rate, followed by U-238 with 34% and Th-232 with 9%. This value of 0.1% of the limit allows to state that, in the operational conditions analyzed, natural radionuclides do not represent a radiological problem to biota.

  11. Absorbed dose rate due to intake of natural radionuclides by Tilapia fish (Tilapia nilotica, Linnaeus, 1758) estimated near uranium anomaly at Santa Quiteria, Ceara, Brazil

    International Nuclear Information System (INIS)

    Pereira, Wagner de; Kelecom, Alphonse; Py Junior, Delcy de Azevedo

    2007-01-01

    The uranium mining at Santa Quiteria (Santa Quiteria Unit - USQ) is in its environmental licensing phase. Aiming to estimate the radiological environmental impact of the USQ, a monitoring program is underway. However, radioprotection of biota is not explicitly mentioned in Brazilian norms. In order to preserve the biota of the deleterious effects from radiation and to behave in a pro-active way as expected by licensing organs, the present work aims to use an environmental protection methodology, based on the calculation of absorbed dose rate in biota. Thus, selected biomarker was the fish tilapia (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). Since there are no exposition limits for biota, in Brazil, the value proposed by the Department of Energy (DOE) of the United States of 3.5 x 10 3 μGy/y has been used. The derived absorbed dose rate calculated for tilapia was 2.76 x 10 0 μGy/y, that is less than 0.1 % of the limit established by DOE. The critical radionuclide was U-238, with 99% of the absorbed dose rate. This value of 0.1% of the limit allows to state that in pre-operational conditions analyzed natural radionuclides do not represent a radiological problem to the biota. (author)

  12. Absorbed dose rate due to intake of natural radionuclides by Tilapia fish (Tilapia nilotica, Linnaeus, 1758) estimated near uranium anomaly at Santa Quiteria, Ceara, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Wagner de [Industrias Nucleares do Brasil S.A. (INB), Pocos de Caldas, MG (Brazil). Coordenacao de Protecao Radiologica. Unidade de Tratamento de Minerios], E-mail: wspereira@inb.gov.br; Kelecom, Alphonse [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Programa de Pos-graduacao em Ciencia Ambiental; Py Junior, Delcy de Azevedo [Industrias Nucleares do Brasil S.A. (INB), Caetite, BA (Brazil). Coordenacao de Protecao Radiologica. Unidade de Concentrado de Uranio], E-mail: Delcy@inb.gov.br

    2007-07-01

    The uranium mining at Santa Quiteria (Santa Quiteria Unit - USQ) is in its environmental licensing phase. Aiming to estimate the radiological environmental impact of the USQ, a monitoring program is underway. However, radioprotection of biota is not explicitly mentioned in Brazilian norms. In order to preserve the biota of the deleterious effects from radiation and to behave in a pro-active way as expected by licensing organs, the present work aims to use an environmental protection methodology, based on the calculation of absorbed dose rate in biota. Thus, selected biomarker was the fish tilapia (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). Since there are no exposition limits for biota, in Brazil, the value proposed by the Department of Energy (DOE) of the United States of 3.5 x 10{sup 3} {mu}Gy/y has been used. The derived absorbed dose rate calculated for tilapia was 2.76 x 10{sup 0} {mu}Gy/y, that is less than 0.1 % of the limit established by DOE. The critical radionuclide was U-238, with 99% of the absorbed dose rate. This value of 0.1% of the limit allows to state that in pre-operational conditions analyzed natural radionuclides do not represent a radiological problem to the biota. (author)

  13. Absorbed Dose Rate Due to Intake of Natural Radionuclides by Tilapia Fish (Tilapia nilotica,Linnaeus, 1758) Estimated Near Uranium Mining at Caetite, Bahia, Brazil

    International Nuclear Information System (INIS)

    Pereira, Wagner de S; Kelecom, Alphonse; Azevedo Py Junior, Delcy de

    2008-01-01

    The uranium mining at Caetite (Uranium Concentrate Unit--URA) is in its operational phase. Aiming to estimate the radiological environmental impact of the URA, a monitoring program is underway. In order to preserve the biota of the deleterious effects from radiation and to act in a pro-active way as expected from a licensing body, the present work aims to use an environmental protection methodology based on the calculation of absorbed dose rate in biota. Thus, selected target organism was the Tilapia fish (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). As, in Brazil there are no radiation exposure limits adopted for biota the value proposed by the Department of Energy (DOE) of the United States of 3.5x10 3 μGy y -1 has been used. The derived absorbed dose rate calculated for Tilapia was 2.51x10 0 μGy y -1 , that is less than 0.1% of the dose limit established by DOE. The critical radionuclide was Ra-226, with 56% of the absorbed dose rate, followed by U-238 with 34% and Th-232 with 9%. This value of 0.1% of the limit allows to state that, in the operational conditions analyzed, natural radionuclides do not represent a radiological problem to biota

  14. Quality of ready to serve tilapia fish curry with PUFA in retortable pouches.

    Science.gov (United States)

    Dhanapal, K; Reddy, G V S; Nayak, B B; Basu, S; Shashidhar, K; Venkateshwarlu, G; Chouksey, M K

    2010-09-01

    Studies on the physical, chemical, and microbiological qualities of fresh tilapia meat revealed its suitability for the preparation of ready to eat fish curry packed in retort pouches. Studies on the fatty acid profile of tilapia meat suggest fortification with polyunsaturated fatty acid (PUFA) to increase the nutritional value. Based on the commercial sterility, sensory evaluation, color, and texture profile analysis F(0) value of 6.94 and cook value of 107.24, with a total process time of 50.24 min at 116 °C was satisfactory for the development of tilapia fish curry in retort pouches. Thermally processed ready to eat south Indian type tilapia fish curry fortified with PUFA was developed and its keeping quality studied at ambient temperature. During storage, a slight increase in the fat content of fish meat was observed, with no significant change in the contents of moisture, protein, and ash. The thiobarbituric acid (TBA) values of fish curry significantly increased during storage. Fish curry fortified with 1% cod liver oil and fish curry without fortification (control) did not show any significant difference in the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), during thermal processing and storage. Sensory analysis revealed that fortification of fish curry with cod liver oil had no impact on the quality. Tilapia fish curry processed at 116 °C and F(0) value of 7.0 (with or without fortification of cod liver oil) was fit for consumption, even after a period of 1-y storage in retort pouch. Tilapia is a lean variety of fish with white flesh and therefore an ideal choice as raw material for the development of ready to serve fish products such as fish curry in retort pouches for both domestic and international markets. Ready to eat thermal processed (116 °C and F(0) value of 7.0) south Indian type tilapia fish curry enriched with PUFA and packed in retort pouch was acceptable for consumption even after a storage period of 1 y at ambient

  15. Toxicity, distribution, accumulation and cooking loss of malathion in tissues of tilapia and common carp fishes

    Directory of Open Access Journals (Sweden)

    Hassan, I. M.

    1993-12-01

    Full Text Available The acute toxicity of malathion as an organophosphorus pesticide to both of the tested fish species, i.e. Tilapia nilotica (tilapia and cyprinus carpio (Common carp was followed by estimating the LC50 at intervals from 24h up to 96h. Tilapia was much more susceptible to malathion toxicity when compared with carp and the available data proved that the LG50 of malathion to common carp fish was 5-7 times the LC50 for tilapia. Accumulation of malathion pesticide in some organs (muscles, gills, intestine and liver of both fish species was studied after application of 200, 300 and 400 ppb malathion in water for 28 days. A proportional relation was found in the two fish species between exposure time and the applied concentrations. The rate of malathion accumulation was higher in liver followed by intestine and gills whereas the lowest concentration was found in muscles. Accumulated malathion in tilapia muscles was higher than carp; while a reversible trend was observed in most other organs. Cooking of the same fish species reduced effectively malathion content in their muscles. Frying of fish in oil lead to a higher loss percent of malathion than did the other methods of cooking.

    La toxicidad aguda de malatión, pesticida organofosforado, para las dos especies de pescado analizadas, Tilapia nilotica (tilapia y Cyprinus carpio (carpa común, fue seguida por estimación de la CL50 a intervalos desde las 24h hasta las 96h. Tilapia fue mucho más susceptible a la toxicidad del malatión cuando se comparó con carpa, y los datos disponibles proporcionaron que la CL50 del malatión para carpa común fue de 5-7 veces la GL50 para tilapia. La acumulación del pesticida malatión en algunos órganos (músculos, agallas, intestino e hígado de ambas especies de pescado fue estudiada después de la aplicación de concentraciones de 200, 300 y 400 ppb de malatión en agua durante 28 días. Se encontró una relaci

  16. Preference index supported by motivation tests in Nile tilapia.

    Science.gov (United States)

    Maia, Caroline Marques; Volpato, Gilson Luiz

    2017-01-01

    The identification of animal preferences is assumed to provide better rearing environments for the animals in question. Preference tests focus on the frequency of approaches or the time an animal spends in proximity to each item of the investigated resource during a multiple-choice trial. Recently, a preference index (PI) was proposed to differentiate animal preferences from momentary responses (Sci Rep, 2016, 6:28328, DOI: 10.1038/srep28328). This index also quantifies the degree of preference for each item. Each choice response is also weighted, with the most recent responses weighted more heavily, but the index includes the entire bank of tests, and thus represents a history-based approach. In this study, we compared this PI to motivation tests, which consider how much effort is expended to access a resource. We performed choice tests over 7 consecutive days for 34 Nile tilapia fish that presented with different colored compartments in each test. We first detected the preferred and non-preferred colors of each fish using the PI and then tested their motivation to reach these compartments. We found that fish preferences varied individually, but the results were consistent with the motivation profiles, as individual fish were more motivated (the number of touches made on transparent, hinged doors that prevented access to the resource) to access their preferred items. On average, most of the 34 fish avoided the color yellow and showed less motivation to reach yellow and red colors. The fish also exhibited greater motivation to access blue and green colors (the most preferred colors). These results corroborate the PI as a reliable tool for the identification of animal preferences. We recommend this index to animal keepers and researchers to identify an animal's preferred conditions.

  17. Preference index supported by motivation tests in Nile tilapia.

    Directory of Open Access Journals (Sweden)

    Caroline Marques Maia

    Full Text Available The identification of animal preferences is assumed to provide better rearing environments for the animals in question. Preference tests focus on the frequency of approaches or the time an animal spends in proximity to each item of the investigated resource during a multiple-choice trial. Recently, a preference index (PI was proposed to differentiate animal preferences from momentary responses (Sci Rep, 2016, 6:28328, DOI: 10.1038/srep28328. This index also quantifies the degree of preference for each item. Each choice response is also weighted, with the most recent responses weighted more heavily, but the index includes the entire bank of tests, and thus represents a history-based approach. In this study, we compared this PI to motivation tests, which consider how much effort is expended to access a resource. We performed choice tests over 7 consecutive days for 34 Nile tilapia fish that presented with different colored compartments in each test. We first detected the preferred and non-preferred colors of each fish using the PI and then tested their motivation to reach these compartments. We found that fish preferences varied individually, but the results were consistent with the motivation profiles, as individual fish were more motivated (the number of touches made on transparent, hinged doors that prevented access to the resource to access their preferred items. On average, most of the 34 fish avoided the color yellow and showed less motivation to reach yellow and red colors. The fish also exhibited greater motivation to access blue and green colors (the most preferred colors. These results corroborate the PI as a reliable tool for the identification of animal preferences. We recommend this index to animal keepers and researchers to identify an animal's preferred conditions.

  18. Radiation decontamination and disinfestation of salted dried tilapia fish (Koobi)

    International Nuclear Information System (INIS)

    Nketsia-Tabiri, J.

    2004-01-01

    Salted dried tilapia (Oreochromis niloticus) fish locally called koobi was investigated with the view of establishing the effective radiation dose for controlling microbial and insect activity on the product. Total viable count (TVC) of market samples of koobi ranged between log 10 4.11 - 6.78 cfu/g, whilst mould and yeast count ranged between log 10 1.38-3.38 cfu/g. Staphylococcus aureus counts ranged between log 10 2.85 - 4.15 cfu/g. After 4 weeks storage under ambient conditions, total viable count increased to log 10 7.5 ± 2.5 cfu/g. Significant reduction in total viable count was observed after treatment with gamma radiation. A least square regression fitted through the data points indicated that 1.3 kGy would be required to reduce the microbial population on the product by one log cycle. Insects and pink colonies of halophilic bacteria were observed on all the nonirradiated samples after 4 weeks storage. Treatment with 3 kGy gamma radiation eliminated all insect forms, while microbial population was controlled with TVC ranging between log 10 1.9 ± 1.1 and log 10 10 2.7 ± 1.6 cfu/g throughout the 16 weeks storage period. The proliferation of halophilic bacteria and subsequent appearance of pink colonies on irradiated koobi was suppressed until the 16th week. Irradiation, therefore, extended the shelf-life of koobi from 4 to 15 weeks. (au)

  19. Assessment of heavy metals and estimation of human health risk in Tilapia fish from Naik lake of Nagpur, India

    Digital Repository Service at National Institute of Oceanography (India)

    Giripunje, M.D.; Fulke, A.B.; Meshram, P.U.

    /g dw respectively. These levels were above the maximum permissible limits of Food and Agriculture Organization (FAO)/World Health Organisation (WHO). The results confirmed that tilapia fish from Naik lake are not safe for human consumption. Further...

  20. Production of red tilapia (Oreochromis spp.) in floating cages in the Mekong Delta, Vietnam: mortality and health management.

    Science.gov (United States)

    Boerlage, Annette S; Dung, Tu Thanh; Hoa, Tran Thi; Davidson, Jeffrey; Stryhn, Henrik; Hammell, K Larry

    2017-04-20

    The Mekong Delta in Vietnam is one of the most productive aquaculture regions in the world, in which the red tilapia (Oreochromis spp.) industry is a small-scale industry that mainly supplies local markets in the delta region. Little is known about the frequency of mortality events and health management in this sector. We describe red tilapia floating cage production systems in the Mekong Delta, Vietnam, for the purposes of quantifying mortality and associated production factors, and describing practices that may influence pathogen introduction and spread to and from farms. In July 2014, approximately 50 red tilapia farmers from 4 provinces (201 farmers in total) were randomly selected and interviewed. Median overall perceived mortality (PM) within a production cycle was 35%. Overall PM was found to be affected by province (p tilapia aquaculture management in the Mekong Delta, and describes management factors that could become important in the event of disease outbreaks.

  1. Management measures to control diseases reported by tilapia (Oreochromis spp.) and whiteleg shrimp (Litopenaeus vannamei) farmers in Guangdong, China

    DEFF Research Database (Denmark)

    Li, Kang; Liu, Liping; Clausen, Jesper Hedegaard

    2016-01-01

    production area in China. Tilapia farmers (25) mainly reported streptococcosis (9) and exophthalmia disease (9) which often was treated with sulfadiazine, florfenicol and vitamins or rhubarb (Rheum rhabarbarum) extract, although farmers thought the effectiveness of antimicrobial treatment has decreased...

  2. La Tilapia en el Perú: acuicultura, mercado, y perspectivas

    Directory of Open Access Journals (Sweden)

    Paúl M. Baltazar

    2013-05-01

    Full Text Available Tilapia es el nombre común con el cual se conocen a diversas especies de los géneros Oreochromis y Tilapia. Las Tilapias son peces de agua dulce endémicos y originarios de África y el Cercano Oriente, aprovechando sus características y adaptabilidad, a comienzos del siglo XIX se inician las investigaciones para utilizarlas en la piscicultura rural, especialmente en el Congo Belga (actualmente Zaire. A partir de 1924 se intensifica su cultivo en Kenia, sin embargo fue en el Extremo Oriente, en Malasia en donde se obtuvieron los mejores resultados y se iniciara su progresivo cultivo en diferentes partes del mundo. En Perú, en la década del 50, la Dirección General de Caza y Pesca del Ministerio de Fomento y Agricultura realizó las primeras introducciones con la especie Tilapia rendalli, utilizada como forraje para el paiche (Arapaina gigas; en la década de los 70, el IMARPE y la Universidad Nacional Agraria La Molina introdujeron las especies Oreochromis niloticus, Oreochromis hornorum y Oreochromis mossambica (Ramos y Gálvez, 2000, con fines de investigación y cultivo en las zonas de selva. La Tilapia roja, Oreochromis spp., ingresa a nuestro país entre los meses de octubre y noviembre de 1996, como parte complementaria de otro lote de reproductores grises, (con el objetivo de evitar la endogamia, procedentes de la Estación DIVISA, Panamá.

  3. Use, fate and ecological risks of antibiotics applied in tilapia cage farming in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Rico, Andreu [Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Oliveira, Rhaul [Department of Biology and CESAM, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); McDonough, Sakchai [Aquaculture and Aquatic Resources Management, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120 (Thailand); Matser, Arrienne [Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Khatikarn, Jidapa [Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Department of Fishery Biology, Faculty of Fisheries, Kasetsart University, Chatuchak 10900, Bangkok (Thailand); Satapornvanit, Kriengkrai [Department of Fishery Biology, Faculty of Fisheries, Kasetsart University, Chatuchak 10900, Bangkok (Thailand); Nogueira, António J.A.; Soares, Amadeu M.V.M.; Domingues, Inês [Department of Biology and CESAM, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Van den Brink, Paul J. [Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands)

    2014-08-01

    The use, environmental fate and ecological risks of antibiotics applied in tilapia cage farming were investigated in the Tha Chin and Mun rivers in Thailand. Information on antibiotic use was collected through interviewing 29 farmers, and the concentrations of the most commonly used antibiotics, oxytetracycline (OTC) and enrofloxacin (ENR), were monitored in river water and sediment samples. Moreover, we assessed the toxicity of OTC and ENR on tropical freshwater invertebrates and performed a risk assessment for aquatic ecosystems. All interviewed tilapia farmers reported to routinely use antibiotics. Peak water concentrations for OTC and ENR were 49 and 1.6 μg/L, respectively. Antibiotics were most frequently detected in sediments with concentrations up to 6908 μg/kg d.w. for OTC, and 2339 μg/kg d.w. for ENR. The results of this study indicate insignificant short-term risks for primary producers and invertebrates, but suggest that the studied aquaculture farms constitute an important source of antibiotic pollution. - Highlights: • First study assessing the risks of antibiotics applied in freshwater tilapia cages. • Ten antibiotics were reported to be used by tilapia cage farmers in two Thai rivers. • Peak oxytetracycline and enrofloxacin concentrations were in the order of μg/L. • Antibiotic concentrations in river sediments next to cages were up to several mg/kg. • Antibiotics are not posing a short-term risk for pelagic aquatic organisms. - Antibiotics applied in tilapia cage farming in Thailand are released into surrounding aquatic ecosystems and constitute an important source of environmental pollution.

  4. Use, fate and ecological risks of antibiotics applied in tilapia cage farming in Thailand

    International Nuclear Information System (INIS)

    Rico, Andreu; Oliveira, Rhaul; McDonough, Sakchai; Matser, Arrienne; Khatikarn, Jidapa; Satapornvanit, Kriengkrai; Nogueira, António J.A.; Soares, Amadeu M.V.M.; Domingues, Inês; Van den Brink, Paul J.

    2014-01-01

    The use, environmental fate and ecological risks of antibiotics applied in tilapia cage farming were investigated in the Tha Chin and Mun rivers in Thailand. Information on antibiotic use was collected through interviewing 29 farmers, and the concentrations of the most commonly used antibiotics, oxytetracycline (OTC) and enrofloxacin (ENR), were monitored in river water and sediment samples. Moreover, we assessed the toxicity of OTC and ENR on tropical freshwater invertebrates and performed a risk assessment for aquatic ecosystems. All interviewed tilapia farmers reported to routinely use antibiotics. Peak water concentrations for OTC and ENR were 49 and 1.6 μg/L, respectively. Antibiotics were most frequently detected in sediments with concentrations up to 6908 μg/kg d.w. for OTC, and 2339 μg/kg d.w. for ENR. The results of this study indicate insignificant short-term risks for primary producers and invertebrates, but suggest that the studied aquaculture farms constitute an important source of antibiotic pollution. - Highlights: • First study assessing the risks of antibiotics applied in freshwater tilapia cages. • Ten antibiotics were reported to be used by tilapia cage farmers in two Thai rivers. • Peak oxytetracycline and enrofloxacin concentrations were in the order of μg/L. • Antibiotic concentrations in river sediments next to cages were up to several mg/kg. • Antibiotics are not posing a short-term risk for pelagic aquatic organisms. - Antibiotics applied in tilapia cage farming in Thailand are released into surrounding aquatic ecosystems and constitute an important source of environmental pollution

  5. Direct Ionic Regulation of the Activity of Myo-Inositol Biosynthesis Enzymes in Mozambique Tilapia.

    Directory of Open Access Journals (Sweden)

    Fernando D Villarreal

    Full Text Available Myo-inositol (Ins is a major compatible osmolyte in many cells, including those of Mozambique tilapia (Oreochromis mossambicus. Ins biosynthesis is highly up-regulated in tilapia and other euryhaline fish exposed to hyperosmotic stress. In this study, enzymatic regulation of two enzymes of Ins biosynthesis, Ins phosphate synthase (MIPS and inositol monophosphatase (IMPase, by direct ionic effects is analyzed. Specific MIPS and IMPase isoforms from Mozambique tilapia (MIPS-160 and IMPase 1 were selected based on experimental, phylogenetic, and structural evidence supporting their role for Ins biosynthesis during hyperosmotic stress. Recombinant tilapia IMPase 1 and MIPS-160 activity was assayed in vitro at ionic conditions that mimic changes in the intracellular milieu during hyperosmotic stress. The in vitro activities of MIPS-160 and IMPase 1 are highest at alkaline pH of 8.8. IMPase 1 catalytic efficiency is strongly increased during hyperosmolality (particularly for the substrate D-Ins-3-phosphate, Ins-3P, mainly as a result of [Na+] elevation. Furthermore, the substrate-specificity of IMPase 1 towards D-Ins-1-phosphate (Ins-1P is lower than towards Ins-3P. Because MIPS catalysis results in Ins-3P this results represents additional evidence for IMPase 1 being the isoform that mediates Ins biosynthesis in tilapia. Our data collectively demonstrate that the Ins biosynthesis enzymes are activated under ionic conditions that cells are exposed to during hypertonicity, resulting in Ins accumulation, which, in turn, results in restoration of intracellular ion homeostasis. We propose that the unique and direct ionic regulation of the activities of Ins biosynthesis enzymes represents an efficient biochemical feedback loop for regulation of intracellular physiological ion homeostasis during hyperosmotic stress.

  6. Direct Ionic Regulation of the Activity of Myo-Inositol Biosynthesis Enzymes in Mozambique Tilapia.

    Science.gov (United States)

    Villarreal, Fernando D; Kültz, Dietmar

    2015-01-01

    Myo-inositol (Ins) is a major compatible osmolyte in many cells, including those of Mozambique tilapia (Oreochromis mossambicus). Ins biosynthesis is highly up-regulated in tilapia and other euryhaline fish exposed to hyperosmotic stress. In this study, enzymatic regulation of two enzymes of Ins biosynthesis, Ins phosphate synthase (MIPS) and inositol monophosphatase (IMPase), by direct ionic effects is analyzed. Specific MIPS and IMPase isoforms from Mozambique tilapia (MIPS-160 and IMPase 1) were selected based on experimental, phylogenetic, and structural evidence supporting their role for Ins biosynthesis during hyperosmotic stress. Recombinant tilapia IMPase 1 and MIPS-160 activity was assayed in vitro at ionic conditions that mimic changes in the intracellular milieu during hyperosmotic stress. The in vitro activities of MIPS-160 and IMPase 1 are highest at alkaline pH of 8.8. IMPase 1 catalytic efficiency is strongly increased during hyperosmolality (particularly for the substrate D-Ins-3-phosphate, Ins-3P), mainly as a result of [Na+] elevation. Furthermore, the substrate-specificity of IMPase 1 towards D-Ins-1-phosphate (Ins-1P) is lower than towards Ins-3P. Because MIPS catalysis results in Ins-3P this results represents additional evidence for IMPase 1 being the isoform that mediates Ins biosynthesis in tilapia. Our data collectively demonstrate that the Ins biosynthesis enzymes are activated under ionic conditions that cells are exposed to during hypertonicity, resulting in Ins accumulation, which, in turn, results in restoration of intracellular ion homeostasis. We propose that the unique and direct ionic regulation of the activities of Ins biosynthesis enzymes represents an efficient biochemical feedback loop for regulation of intracellular physiological ion homeostasis during hyperosmotic stress.

  7. Dopamine inhibits somatolactin gene expression in tilapia pituitary cells through the dopamine D2 receptors.

    Science.gov (United States)

    Jiang, Quan; Lian, Anji; He, Qi

    2016-07-01

    Dopamine (DA) is an important neurotransmitter in the central nervous system of vertebrates and possesses key hypophysiotropic functions. Early studies have shown that DA has a potent inhibitory effect on somatolactin (SL) release in fish. However, the mechanisms responsible for DA inhibition of SL gene expression are largely unknown. To this end, tilapia DA type-1 (D1) and type-2 (D2) receptor transcripts were examined in the neurointermediate lobe (NIL) of the tilapia pituitary by real-time PCR. In tilapia, DA not only was effective in inhibiting SL mRNA levels in vivo and in vitro, but also could abolish pituitary adenylate cyclase-activating polypeptide (PACAP)- and salmon gonadotropin-releasing hormone (sGnRH)-stimulated SL gene expression at the pituitary level. In parallel studies, the specific D2 receptor agonists quinpirole and bromocriptine could mimic the DA-inhibited SL gene expression. Furthermore, the D2 receptor antagonists domperidone and (-)-sulpiride could abolish the SL response to DA or the D2 agonist quinpirole, whereas D1 receptor antagonists SCH23390 and SKF83566 were not effective in this respect. In primary cultures of tilapia NIL cells, D2 agonist quinpirole-inhibited cAMP production could be blocked by co-treatment with the D2 antagonist domperidone and the ability of forskolin to increase cAMP production was also inhibited by quinpirole. Using a pharmacological approach, the AC/cAMP pathway was shown to be involved in quinpirole-inhibited SL mRNA expression. These results provide evidence that DA can directly inhibit SL gene expression at the tilapia pituitary level via D2 receptor through the AC/cAMP-dependent mechanism. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Derivation and Osmotolerance Characterization of Three Immortalized Tilapia (Oreochromis mossambicus) Cell Lines

    Science.gov (United States)

    Gardell, Alison M.; Qin, Qin; Rice, Robert H.; Li, Johnathan; Kültz, Dietmar

    2014-01-01

    Fish cell cultures are becoming more widely used models for investigating molecular mechanisms of physiological response to environmental challenge. In this study, we derived two immortalized Mozambique tilapia (Oreochromis mossambicus) cell lines from brain (OmB) and lip epithelium (OmL), and compared them to a previously immortalized bulbus arteriosus (TmB) cell line. The OmB and OmL cell lines were generated without or with Rho-associated kinase (ROCK) inhibitor/3T3 feeder layer supplementation. Although both approaches were successful, ROCK inhibitor/feeder layer supplementation was found to offer the advantages of selecting for epithelial-like cell type and decreasing time to immortalization. After immortalization (≥ passage 5), we characterized the proteomes of the newly derived cell lines (OmB and OmL) using LCMS and identified several unique cell markers for each line. Subsequently, osmotolerance for each of the three cell lines following acute exposure to elevated sodium chloride was evaluated. The acute maximum osmotolerance of these tilapia cell lines (>700 mOsm/kg) was markedly higher than that of any other known vertebrate cell line, but was significantly higher in the epithelial-like OmL cell line. To validate the physiological relevance of these tilapia cell lines, we quantified the effects of acute hyperosmotic challenge (450 mOsm/kg and 700 mOsm/kg) on the transcriptional regulation of two enzymes involved in biosynthesis of the compatible organic osmolyte, myo-inositol. Both enzymes were found to be robustly upregulated in all three tilapia cell lines. Therefore, the newly established tilapia cells lines represent valuable tools for studying molecular mechanisms involved in the osmotic stress response of euryhaline fish. PMID:24797371

  9. Regulation of gill claudin paralogs by salinity, cortisol and prolactin in Mozambique tilapia (Oreochromis mossambicus).

    Science.gov (United States)

    Tipsmark, Christian K; Breves, Jason P; Rabeneck, D Brett; Trubitt, Rebecca T; Lerner, Darren T; Grau, E Gordon

    2016-09-01

    In euryhaline teleosts, reorganization of gill tight junctions during salinity acclimation involves dynamic expression of specific claudin (Cldn) paralogs. We identified four transcripts encoding Cldn tight junction proteins in the tilapia gill transcriptome: cldn10c, cldn10e, cldn28a and cldn30. A tissue distribution experiment found cldn10c and cldn10e expression levels in the gill to be 100-fold higher than any other tissues examined. cldn28a and cldn30 levels in the gill were 10-fold greater than levels in other tissues. Expression of these genes in Mozambique tilapia was examined during acclimation to fresh water (FW), seawater (SW), and in response to hormone treatments. Transfer of tilapia from FW to SW elevated cldn10c and cldn10e, while cldn28a and cldn30 were stimulated following transfer from SW to FW. In hypophysectomized tilapia transferred to FW, pituitary extirpation induced reduced expression of cldn10c, cldn10e and cldn28a; these effects were mitigated equally by either prolactin or cortisol replacement. In vitro experiments with gill filaments showed that cortisol stimulated expression of all four cldns examined, suggesting a direct action of cortisol in situ. Our data indicate that elevated cldn10c and cldn10e expression is important during acclimation of tilapia to SW possibly by conferring ion specific paracellular permeability. On the other hand, expression of cldn28a and cldn30 appears to contribute to reorganization of branchial epithelium during FW acclimation. Hormone treatment experiments showed that particular FW- and SW-induced cldns are controlled by cortisol and prolactin. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Chemical communication in tilapia: a comparison of Oreochromis mossambicus with O. niloticus.

    Science.gov (United States)

    Hubbard, Peter C; Mota, Vasco C; Keller-Costa, Tina; da Silva, José Paulo; Canário, Adelino V M

    2014-10-01

    In allopatric speciation species differentiation generally results from different selective pressures in different environments, and identifying the traits responsible helps to understand the isolation mechanism(s) involved. Male Mozambique tilapia (Oreochromis mossambicus) use urine to signal dominance; furthermore, 5β-pregnane-3α,17,20β-triol-3α-glucuronide (and its α-epimer, 5β-pregnane-3α,17,20α-triol-3α-glucuronide), in their urine is a potent pheromone, the concentration of which is correlated with social status. The Nile tilapia (Oreochromisniloticus) is a close relative; species divergence probably resulted from geographical separation around 6 million years ago. This raises the question of whether the two species use similar urinary chemical cues during reproduction. The olfactory potency of urine, and crude extracts, from either species was assessed by the electro-olfactogram and the presence of the steroid glucuronides in urine from the Nile tilapia by liquid-chromatography/mass-spectrometry. Both species showed similar olfactory sensitivity to urine and respective extracts from either species, and similar sensitivity to the steroid glucuronides. 5β-Pregnan-3α,17α,20β-triol-3α-glucuronide was present at high concentrations (approaching 0.5mM) in urine from Nile tilapia, with 5β-pregnan-3α,17α,20α-triol-3α-glucuronide present at lower concentrations, similar to the Mozambique tilapia. Both species also had similar olfactory sensitivity to estradiol-3-glucuronide, a putative urinary cue from females. Together, these results support the idea that reproductive chemical cues have not been subjected to differing selective pressure. Whether these chemical cues have the same physiological and behavioural roles in O. niloticus as O. mossambicus remains to be investigated. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. The Effect of Dietary Phytase Supplementation and Incubation in Soy Protein Concentrate based diet Fed to Nile Tilapia

    OpenAIRE

    Xue, Yuhang

    2015-01-01

    Aquatic feed require high quality, low cost nutrients with increasing aquaculture production. Tilapia has become the third most important cultured fish species in the world, just after salmonids and carps. Soybean and its products are the most popular source of plant protein in compound aquatic feeds. In the existing plant protein sources phytate-P absorption and digestion is low in Nile Tilapia. This experiment aimed to investigate the different effects on retention and utilization o...

  12. Dietary supplementation of yeast (Saccharomyces cerevisiae) improves growth, stress tolerance, and disease resistance in juvenile Nile tilapia (Oreochromis niloticus)

    DEFF Research Database (Denmark)

    Abass, David Attim; Obirikorang, Kwasi Adu; Campion, Benjamin Betey

    2018-01-01

    resistance in juvenile (body mass ~ 21 g) Nile tilapia (Oreochromis niloticus). Fish were randomly distributed in groups of 20 into 12 1-m³ hapas and fed isoenergetic (~ 17 kJ g⁻¹ gross energy) and isonitrogenous (~ 300 g kg⁻¹ crude protein) diets at 3% of their bulk weight daily. Specific growth rates were...... as an additive in Nile tilapia diets has beneficial impacts on growth, stress tolerance, and disease resistance...

  13. COMPARACIÓN SENSORIAL DE TRES FORMULACIONES DE HAMBURGUESAS ELABORADAS A BASE DE TILAPIA ROJA (Oreochromis sp..

    Directory of Open Access Journals (Sweden)

    JOSÉ IGOR HLEAP ZAPATA

    2013-12-01

    Full Text Available Se evaluaron sensorialmente hamburguesas elaboradas a base de tilapia roja y dos formulaciones adicionales, en las cuales se sustituyó un porcentaje de tilapia roja por carne de res, en una, y de cerdo, en la otra. Se plantearon tres formulaciones diferentes: solo de carne de tilapia roja codificada con la cifra aleatoria 8204 y carne de tilapia adicionadas con carne de res y carne de cerdo, identificadas con las cifras 6271 y 3522 respectivamente. Las hamburguesas se sometieron a degustaciones realizadas por un panel de 100 consumidores no entrenados, utilizando una escala hedónica de siete puntos. Se valoró estadísticamente la aprobación de los productos y se determinó que hubo buen agrado y buena aceptación. Los resultados indicaron una conformidad del 75% para la muestra 8204, mientras que para las muestras 6271 y 3522, ésta fue respectivamente de 78% y 82%. A pesar de que se presentaron algunas diferencias entre el porcentaje de aceptación de las tres formulaciones, el intervalo de varianza no es significativo, lo cual permitió concluir que los tres productos analizados fueron de completa satisfacción. Se concluyó que las diferencias entre las hamburguesas elaboradas solo a base de tilapia versus las elaboradas a base de tilapia con adición de otras carnes no influyeron en la aceptación por los consumidores.

  14. Maternal mismatches in farmed tilapia strains (Oreochromis spp.) in the Philippines as revealed by mitochondrial COI gene.

    Science.gov (United States)

    Ordoñez, June Feliciano F; Ventolero, Minerva Fatimae H; Santos, Mudjekeewis D

    2017-07-01

    The introduction of genetically enhanced tilapia has significantly boosted the performance of Philippine aquaculture industry. While enhanced strains contribute to the increase in tilapia production, genetic characterization of present tilapia stocks is critical to maintain their quality and to ensure the genetic gains are sustained. To understand and determine the genetic relationship of the genetically enhanced strains produced in the Philippines, mitochondrial cytochrome oxidase subunit I (COI) gene using DNA barcoding approach was analyzed. Specimens representing 10 genetically enhanced strains (GIFT, FaST, GET-EXCEL, GST, SST, COLD, YY-male, GMT, Molobicus, and BEST), three red tilapia (Taiwan red, Florida red, and FAC-red), and two pure lines (initially identified as O. aureus and O. spilurus) were collected, sequenced, and identified using DNA barcoding. Results revealed that farmed tilapias consisted of four different Oreochromis species. As expected, COI could not distinguish individuals at the strain level but surprisingly, mismatch between the species of maternal origin and present-day offspring was observed. This particular result may pose a question on the genetic purity and integrity of the strains being distributed to farmers and suggests a re-evaluation of the effectiveness of major tilapia breeding centers in maintaining their stocks.

  15. A microsatellite-based linkage map of salt tolerant tilapia (Oreochromis mossambicus x Oreochromis spp.) and mapping of sex-determining loci

    Science.gov (United States)

    2013-01-01

    Background Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution. Results We constructed a consensus linkage map of Mozambique tilapia and red tilapia using 95 individuals from two F1 families and 401 microsatellites including 282 EST-derived markers. In addition, we conducted comparative mapping and searched for sex-determining loci on the whole genome. These 401 microsatellites were assigned to 22 linkage groups. The map spanned 1067.6 cM with an average inter-marker distance of 3.3 cM. Comparative mapping between tilapia and stickleback, medaka, pufferfish and zebrafish revealed clear homologous relationships between chromosomes from different species. We found evidence for the fusion of two sets of two independent chromosomes forming two new chromosome pairs, leading to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex determination locus in Mozambique tilapia was mapped on LG1, and verified in five families containing 549 individuals. The major XY sex determination locus in red tilapia was located on LG22, and verified in two families containing 275 individuals. Conclusions A first-generation linkage map of salt tolerant tilapia was constructed using 401 microsatellites. Two separate fusions of two sets of two independent chromosomes may lead to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex-determining loci from Mozambique tilapia and red tilapia were mapped on LG1 and LG22, respectively. This map provides a useful resource for QTL mapping for important traits and comparative genome studies. The DNA markers linked to the sex-determining loci could be used in

  16. A microsatellite-based linkage map of salt tolerant tilapia (Oreochromis mossambicus x Oreochromis spp. and mapping of sex-determining loci

    Directory of Open Access Journals (Sweden)

    Liu Feng

    2013-01-01

    Full Text Available Abstract Background Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution. Results We constructed a consensus linkage map of Mozambique tilapia and red tilapia using 95 individuals from two F1 families and 401 microsatellites including 282 EST-derived markers. In addition, we conducted comparative mapping and searched for sex-determining loci on the whole genome. These 401 microsatellites were assigned to 22 linkage groups. The map spanned 1067.6 cM with an average inter-marker distance of 3.3 cM. Comparative mapping between tilapia and stickleback, medaka, pufferfish and zebrafish revealed clear homologous relationships between chromosomes from different species. We found evidence for the fusion of two sets of two independent chromosomes forming two new chromosome pairs, leading to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex determination locus in Mozambique tilapia was mapped on LG1, and verified in five families containing 549 individuals. The major XY sex determination locus in red tilapia was located on LG22, and verified in two families containing 275 individuals. Conclusions A first-generation linkage map of salt tolerant tilapia was constructed using 401 microsatellites. Two separate fusions of two sets of two independent chromosomes may lead to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex-determining loci from Mozambique tilapia and red tilapia were mapped on LG1 and LG22, respectively. This map provides a useful resource for QTL mapping for important traits and comparative genome studies. The DNA markers linked to the sex

  17. Detection of natural infection of infectious spleen and kidney necrosis virus in farmed tilapia by hydroxynapthol blue-loop-mediated isothermal amplification assay.

    Science.gov (United States)

    Suebsing, R; Pradeep, P J; Jitrakorn, S; Sirithammajak, S; Kampeera, J; Turner, W A; Saksmerprome, V; Withyachumnarnkul, B; Kiatpathomchai, W

    2016-07-01

    Infectious spleen and kidney necrosis virus (ISKNV) has recently been recognized as a causative agent of serious systemic disease in tilapia. Our objective was to establish a new colorimetric loop-mediated isothermal amplification (LAMP) assay with pre-addition of hydroxynapthol blue (blue-LAMP) to investigate ISKNV transmission in tilapia. The blue-LAMP, targeting a major capsid protein gene of ISKNV, was conducted at 65°C for 45 min, allowing unaided visual detection of the pathogen based on colour change without cross-amplification of other known fish pathogens tested. Comparison of blue-LAMP and PCR assays revealed a higher detection level for blue-LAMP assay (41·33%) in a population of farmed tilapia infected with ISKNV. The investigation of ISKNV transmission pattern in farmed red tilapia using the blue-LAMP revealed a possible matroclinical form. The presence of ISKNV in the gonad samples was confirmed by in situ LAMP assay. Positive signals only appeared in ovarian follicles, and not in oocytes. Moreover, tissue tropism assay revealed that the brain was the main target organ in both farmed red tilapia (40%) and Nile tilapia (20%). The developed blue-LAMP assay has the potential to be used as a viable tool for screening covert and natural infections of ISKNV in tilapia. The evidence of vertical transmission of ISKNV infection in tilapia indicates the seriousness of this disease and will require a close attention and collaboration between tilapia hatcheries and disease experts in order to find a solution. The new blue-LAMP assay is a time-saving and economically viable detection tool, which allows unaided visual detection for ISKNV in tilapia, and it could be applicable for field applications. Evidence on the vertical transmission of ISKNV in farmed tilapia suggests a need for developing farm management practices to control the spread of virus in aquaculture industries. © 2016 The Society for Applied Microbiology.

  18. Study of the Antimicrobial Activity of Tilapia Piscidin 3 (TP3) and TP4 and Their Effects on Immune Functions in Hybrid Tilapia (Oreochromis spp.)

    Science.gov (United States)

    Pan, Chieh-Yu; Tsai, Tsung-Yu; Su, Bor-Chyuan; Hui, Cho-Fat; Chen, Jyh-Yih

    2017-01-01

    To address the growing concern over antibiotic-resistant microbial infections in aquatic animals, we tested several promising alternative agents that have emerged as new drug candidates. Specifically, the tilapia piscidins are a group of peptides that possess antimicrobial, wound-healing, and antitumor functions. In this study, we focused on tilapia piscidin 3 (TP3) and TP4, which are peptides derived from Oreochromis niloticus, and investigated their inhibition of acute bacterial infections by infecting hybrid tilapia (Oreochromis spp.) with Vibrio vulnificus and evaluating the protective effects of pre-treating, co-treating, and post-treating fish with TP3 and TP4. In vivo experiments showed that co-treatment with V. vulnificus and TP3 (20 μg/fish) or TP4 (20 μg/fish) achieved 95.3% and 88.9% survival rates, respectively, after seven days. When we co-injected TP3 or TP4 and V. vulnificus into tilapia and then re-challenged the fish with V. vulnificus after 28 days, the tilapia exhibited survival rates of 35.6% and 42.2%, respectively. Pre-treatment with TP3 (30 μg/fish) or TP4 (20 μg/fish) for 30 minutes prior to V. vulnificus infection resulted in high survival rates of 28.9% and 37.8%, respectively, while post-treatment with TP3 (20 μg/fish or 30 μg/fish) or TP4 (20 μg/fish) 30 minutes after V. vulnificus infection yielded high survival rates of 33.3% and 48.9%. In summary, pre-treating, co-treating, and post-treating fish with TP3 or TP4 all effectively decreased the number of V. vulnificus bacteria and promoted significantly lower mortality rates in tilapia. The minimum inhibitory concentrations (MICs) of TP3 and TP4 that were effective for treating fish infected with V. vulnificus were 7.8 and 62.5 μg/ml, respectively, whereas the MICs of kanamycin and ampicillin were 31.2 and 3.91 μg/ml. The antimicrobial activity of these peptides was confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), both of which showed

  19. Diseases and treatment reported by shrimp and tilapia farmers in Guangdong Province, China

    DEFF Research Database (Denmark)

    Li, Kang; Liu, Liping; Clausen, Jesper Hedegaard

    chemicals are used to prevent and control diseases and manage pond environments. This questionnaire-based interview study with aquaculture farmers aimed to describe disease management practices and chemical usage patterns by farmers. Tilapia grow-out farmers (25) mainly reported streptococcosis (9...... for disease treatment. Tilapia and shrimp farmers obtained more and more technical service from staff in chemical shops, chemical and feed companies on diagnosing and treatment of diseases, and acquired information about prudent and safe application practices of chemicals more easily from different pathways...... in recent years. However, many farmers from small family farms still mainly relied on their own experiences. The study shows the improving in aquaculture practicing in China, but still an urgent need to increase farmer’s knowledge on how to prevent and control diseases and use chemicals, including...

  20. Nutritional, microbiological and sensorial characteristics of alfajor prepared with dehydrated mixture of salmon and tilapia

    Directory of Open Access Journals (Sweden)

    Kátia Setsuko Kimura

    2017-02-01

    Full Text Available Current assay deals with the preparation of alfajores with different levels (0 to 15% of dehydrated fish mixture of salmon (10% and tilapia (90% to assess the sensorial characteristics and their centesimal composition and microbiological. Fish inclusion in alfajores did not affect the aroma, taste, texture, color and physical aspect, with scores ranging between 6.70 and 7.96 of a hedonic scale of 9 score. An average score of 4 in a 5-score purchasing intention scale was obtained, or rather, tasters would probably buy the product. In the case of centesimal composition, inclusion affected (p 0.05 in lipids and calorie rates in the alfajores. Results show that the inclusion of up to 15% of a dehydrated mixture of salmon (10% and tilapia (90% in alfajores was greatly accepted and improved their nutrition values. Further, the product was also within the microbiological standards required by Brazilian sanitary laws.

  1. Chemical changes after irradiation and post-irradiation storage in tilapia and Spanish mackerel

    International Nuclear Information System (INIS)

    Al-Kahtani, H.A.; Abu-Tarboush, H.M.; Bajaber, A.S.; Atia, M.; Abou-Arab, A.A.; El-Mojaddidi, M.A.

    1996-01-01

    Influence of gamma irradiation (1.5-10 kGy) and post-irradiation storage up to 20 days at 2 +/- 2 degrees C on some chemical criteria of tilapia and spanish mackerel were studied. Total volatile basic nitrogen formation was lower in irradiated fish than in the unirradiated. Irradiation also caused a larger increase in thiobarbituric acid values which continued gradually during storage. Some fatty acids decreased by irradiation treatments at all doses. Thiamin loss was more severe at higher doses (greater than or equal to 4.5 kGy), whereas riboflavin was not affected. Alpha and gamma tocopherols of tilapia and alpha, beta, gamma, and delta tocopherols, in Spanish mackerel, decreased with increased dose and continued to decrease during 20-day post-irradiation storage

  2. Magnesium and its transport in tilapia and carp: A study based on nuclear methods. Thesis

    Energy Technology Data Exchange (ETDEWEB)

    van der Velden, J.A.

    1993-01-01

    The experiments described in this thesis deal with the production of radiotracers for magnesium and the magnesium metabolism of freshwater tilapia and carp. In chapter 2 the technique of instrumental neutron activation analysis, and the production and properties of two radioisotopes of magnesium are described. In chapter 3 the magnesium distribution and the magnesium inventory of carp and tilapia is described, mainly by the use of instrumental neutron activation analysis. Chapter 4 deals with magnesium transport (in vivo and in vitro) between the water and fish and food and fish. In chapter 5 effects of a low-magnesium diet on tissue mineral concentrations, on the ion regulation and on magnesium transport of fish is described. Chapter 6 deals with the effects of low ambient magnesium on early life stages of the fish.

  3. Hematology and productive performance of nile tilapia (Oreochromis niloticus naturally infected with Flavobacterium columnare

    Directory of Open Access Journals (Sweden)

    F. A Sebastião

    2011-03-01

    Full Text Available Columnaris disease is one of the main causes of mortality in tilapia rearing and is responsible for large economic losses worldwide. Hematology is a tool that makes it possible to study organisms' physiological responses to pathogens. It may assist in making diagnoses and prognoses on diseases in fish populations. The hematological variables of nile tilapia were studied in specimens with a clinical diagnosis of columnaris disease and in specimens that were disease-free. The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV, organic defense blood cell percentages (leukocytes and thrombocytes and hepatosomatic and splenosomatic index were determined. The results showed that there were changes in the erythrocytic series and in organic defense blood cells, in the fish infected with the bacterium, with reductions in erythrocytic variables and significant increases in the numbers of circulating lymphocytes and neutrophils.

  4. Effects of Microcystis on Hypothalamic-Pituitary-Gonadal-Liver Axis in Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Chen, Jiazhang; Meng, Shunlong; Xu, Hai; Zhang, Zhen; Wu, Xiangyang

    2017-04-01

    In the present study, Nile tilapia (Oreochromis niloticus) were used to assess the endocrine disruption potential of Microcytis aeruginosa. Male Nile tilapia were exposed to lyophilized M. aeruginosa or purified microcystin-LR (8.3 μg/L) for 28 days. The levels of serum hormones (17β-estradiol and testosterone) and transcripts of selected genes in the hypothalamus-pituitary-gonadal-liver axis were analyzed. The results showed that serum hormones were significantly up-regulated, and transcripts of 13 genes (GHRH, PACAP, GH, GHR1, GHR2, IGF1, IGF2, CYP19a, CYP19b, 3β-HSD1, 20β-HSD, 17β-HSD1 and 17β-HSD8) were significantly altered after Microcytis exposure. These results indicate that fish reproduction can be altered in a Microcystis bloom-contaminated aquatic environment.

  5. Rapid identification of pathogenic streptococci isolated from moribund red tilapia (Oreochromis spp.).

    Science.gov (United States)

    Abdelsalam, Mohamed; Elgendy, Mamdouh Y; Shaalan, Mohamed; Moustafa, Mohamed; Fujino, Masayuki

    2017-03-01

    Accurate and rapid identification of bacterial pathogens of fish is essential for the effective treatment and speedy control of infections. Massive mortalities in market-sized red tilapia (Oreochromis spp.) were noticed in mariculture concrete ponds in northern Egypt. Histopathological examination revealed marked congestion in the central vein of the liver with the presence of bacterial aggregates inside the lumen and in the vicinity of the central vein. A total of 12 isolates of streptococci were obtained from the moribund fish. This study documented the ability of the MicroSeq 500 16S bacterial sequencing method to accurately identify Streptococcus agalactiae and S. dysgalactiae mixed infections from moribund red tilapia that were difficult to be recognised by the commercial biochemical systems. The continuously decreasing cost of the sequencing technique should encourage its application in routine diagnostic procedures.

  6. Étude des lésions anatomo-pathologiques des Tilapia et Clarias ...

    African Journals Online (AJOL)

    SARAH

    29 déc. 2014 ... marchés de Lubumbashi témoignent de la mauvaise qualité du produit consommé à cause du danger présenté pour l'homme (toxi- ... Mots- clés: Poisson, Tilapia, Clarias, lésions anatomo-pathologiques, marché, Lubumbashi. ABSTRACT ... sequestration of fishing products that pose a danger to the public.

  7. Selection for growth of Nile tilapia (Oreochromis niloticus L.) in low-input environments

    NARCIS (Netherlands)

    Charo-Karisa, H.

    2006-01-01

    Nile tilapia,Oreochromis niloticus,is one of the most important species farmed in the world and is the mainstay of many

  8. Sources and fate of antimicrobials in integrated fish-pig and non-integrated tilapia farms.

    Science.gov (United States)

    Li, Kang; Liu, Liping; Zhan, Jia; Scippo, Marie-Louise; Hvidtfeldt, Kristian; Liu, Yuan; Dalsgaard, Anders

    2017-10-01

    Antimicrobial contamination in aquaculture products constitutes a food safety hazard, but little is known about the introduction and accumulation of antimicrobials in integrated fish-pig aquaculture. This study, conducted in 2013, aimed to determine the residues of 11 types of antimicrobials by UPLC-MS/MS analysis in fish feed (n=37), pig feed (n=9), pig manure (n=9), pond sediment (n=20), fish skin (n=20) and muscle tissue (n=20) sampled from integrated tilapia-pig farms, non-integrated tilapia farms and fish feed supply shops. There was a higher occurrence of antimicrobial residues in fish skin from both integrated and non-integrated farms, and in pig manure. Enrofloxacin (3.9-129.3μg/kg) and sulfadiazine (0.7-7.8μg/kg) were commonly detected in fish skin and muscle, pig manure and pond sediment from integrated farms, with different types of antimicrobials found in pig manure and tilapia samples. In non-integrated farms, sulfadiazine (2.5-89.9μg/kg) was the predominant antimicrobial detected in fish skin and muscle, fish feed and pond sediment. In general, antimicrobials seemed not to be commonly transmitted from pig to fish in tilapia-pig integrated farms, and fish feed, pig feed and pond sediment did not seem as important sources of the antimicrobials found in fish from both systems. The frequent findings of antimicrobial residues in fish skin compared with fish muscle was probably due to different pharmacokinetics in different tissue types, which have practical food safety implications since antimicrobial residues monitoring is usually performed analyzing mixed skin and fish muscle samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Comprehensive evaluation of immunomodulation by moderate hypoxia in S. agalactiae vaccinated Nile tilapia.

    Science.gov (United States)

    Gallage, Sanchala; Katagiri, Takayuki; Endo, Masato; Maita, Masashi

    2017-07-01

    Streptococcus agalactiae is a major bacterial pathogen in tilapia aquaculture. Vaccines are known to provide protection but S. agalactiae clearance in tilapia can be reduced by marginal environmental conditions. Therefore, the purpose of this study is to examine S. agalactiae clearance in vaccinated Nile tilapia under moderate hypoxic (55± 5% DO) and normoxic (85 ± 5%DO) conditions. Fish were acclimatized to either moderate hypoxia or normoxia and immunized with formalin-inactivated S. agalactiae. Fish were experimentally challenged with S. agalactiae at 30 days post-vaccination. Serum antibody titer was significantly higher in vaccinated fish kept under normoxic condition compared to the moderate hypoxic condition at fifteen and thirty days post-vaccination. The cumulative mortality following challenge was significantly reduced in vaccinated fish kept under normoxic condition compared to those in moderate hypoxic condition reflecting that pre-challenge antibody titer may correlate with survival of fish. Blood and tissue pathogen burden detection of S. agalactiae studies revealed that culturable S. agalactiae cells could not be detected in the blood of normoxic vaccinated fish at all the sampling points. In contrast, fish vaccinated in moderate hypoxic condition had considerable number of culturable S. agalactiae cells in their blood up to 5 days following challenge. Phagocytosis and intracellular reactive oxygen species (ROS) production were lowered by moderate hypoxia in vitro. Furthermore, presence of specific antibodies and higher specific antibody level in the serum increased phagocytosis, ROS production and lowered intracellular survival of S. agalactiae in head kidney leukocytes. Overall this study has highlighted that S. agalactiae clearance in vaccinated Nile tilapia is modulated by moderate hypoxia. One of the possible explanations for this might be less efficient phagocytic activities due to low oxygen availability and lower specific

  10. Development of live attenuated Streptococcus agalactiae vaccine for tilapia via continuous passage in vitro.

    Science.gov (United States)

    Li, L P; Wang, R; Liang, W W; Huang, T; Huang, Y; Luo, F G; Lei, A Y; Chen, M; Gan, X

    2015-08-01

    Fish Streptococcus agalactiae (S. agalactiae) seriously harms the world's aquaculture industry and causes huge economic losses. This study aimed to develop a potential live attenuated vaccine of S. agalactiae. Pre-screened vaccine candidate strain S. agalactiae HN016 was used as starting material to generate an attenuated strain S. agalactiae YM001 by continuous passage in vitro. The biological characteristics, virulence, and stability of YM001 were detected, and the protective efficacy of YM001 immunization in tilapia was also determined. Our results indicated that the growth, staining, characteristics of pulsed-field gel electrophoresis (PFGE) genotype, and virulence of YM001 were changed significantly as compared to the parental strain HN016. High doses of YM001 by intraperitoneal (IP) injection (1.0 × 10(9) CFU/fish) and oral gavage (1.0 × 10(10) CFU/fish) respectively did not cause any mortality and morbidity in tilapia. The relative percent survivals (RPSs) of fishes immunized with YM001 (1.0 × 10(8) CFU/fish, one time) via injection, immersion, and oral administration were 96.88, 67.22, and 71.81%, respectively, at 15 days, and 93.61, 60.56, and 53.16%, respectively, at 30 days. In all tests with 1-3 times of immunization in tilapia, the dosages at 1 × 10(8) and 1 × 10(9) CFU/fish displayed the similar best results, whereas the immunoprotection of the dosages at 1 × 10(6) and 1 × 10(7) CFU/fish declined significantly (P 0.05). The level of protective antibody elicited by oral immunization was significantly higher compared to that of the control group (P S. agalactiae strain YM001; oral immunization of tilapia with this strain produced a good immune protection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Comparative proteome analysis of two Streptococcus agalactiae strains from cultured tilapia with different virulence.

    Science.gov (United States)

    Li, Wei; Su, You-Lu; Mai, Yong-Zhan; Li, Yan-Wei; Mo, Ze-Quan; Li, An-Xing

    2014-05-14

    Streptococcus agalactiae is a major piscine pathogen, which causes significant morbidity and mortality among numerous fish species, and results in huge economic losses to aquaculture. Many S. agalactiae strains showing different virulence characteristics have been isolated from infected tilapia in different geographical regions throughout South China in the recent years, including natural attenuated S. agalactiae strain TFJ0901 and virulent S. agalactiae strain THN0901. In the present study, survival of tilapia challenged with S. agalactiae strain TFJ0901 and THN0901 (10(7)CFU/fish) were 93.3% and 13.3%, respectively. Moreover, there are severe lesions of the examined tissues in tilapia infected with strain THN0901, but no significant histopathological changes were observed in tilapia infected with the strain TFJ0901. In order to elucidate the factors responsible for the invasive potential of S. agalactiae between two strains TFJ0901 and THN0901, a comparative proteome analysis was applied to identify the different protein expression profiles between the two strains. 506 and 508 cellular protein spots of S. agalactiae TFJ0901 and THN0901 were separated by two dimensional electrophoresis, respectively. And 34 strain-specific spots, corresponding to 27 proteins, were identified successfully by MALDI-TOF mass spectrometry. Among them, 23 proteins presented exclusively in S. agalactiae TFJ0901 or THN0901, and the other 4 proteins presented in different isomeric forms between TFJ0901 and THN0901. Most of the strain-specific proteins were just involved in metabolic pathways, while 7 of them were presumed to be responsible for the virulence differences of S. agalactiae strain TFJ0901 and THN0901, including molecular chaperone DnaJ, dihydrolipoamide dehydrogenase, thioredoxin, manganese-dependent inorganic pyrophosphatase, elongation factor Tu, bleomycin resistance protein and cell division protein DivIVA. These virulence-associated proteins may contribute to identify new

  12. GapA, a potential vaccine candidate antigen against Streptococcus agalactiae in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zhang, Ze; Yu, Angen; Lan, Jiangfeng; Zhang, Hua; Hu, Minqiang; Cheng, Jiewei; Zhao, Lijuan; Lin, Li; Wei, Shun

    2017-04-01

    Streptococcosis due to the bacterium Streptococcus agalactiae (S. agalactiae) has resulted in enormous economic losses in aquaculture worldwide, especially in the tilapia culture industry. Previously, there were limited vaccines that could be employed against streptococcosis in tilapia. This study aimed to develop a vaccine candidate using the glyceraldehyde-phosphate dehydrogenase protein (GapA) of S. agalactiae encoded by the gapA gene. Tilapia were intraperitoneally injected with PBS, PBS + Freund's adjuvant, PBS + Montanide's adjuvant, GapA + Freund's adjuvant, GapA + Montanide's adjuvant, killed S. agalactiae whole cells (WC)+Freund's adjuvant, or killed S. agalactiae whole cells (WC)+ Montanide's adjuvant. They were then challenged with S. agalactiae, and the relative percentage survival (RPS) was monitored 14 days after the challenge. The highest RPSs were observed in the WC groups, with 76.7% in WC + Freund's adjuvant and 74.4% in WC + Montanide's adjuvant groups; these were followed by the GapA groups, with 63.3% in GapA + Freund's adjuvant and 45.6% in GapA + Montanide's adjuvant groups. The RPS of the PBS group was 0%, and those of PBS + Freund's adjuvant and PBS + Montanide's adjuvant groups were 6.7% and 3.3%, respectively. Additionally, the IgM antibody responses elicited in GapA groups and WC groups were significantly higher than those in PBS groups. Furthermore, the expressions of cytokine (IL-1β and TNF-α) mRNAs in the GapA groups and WC groups were significantly higher than those in the PBS groups. Taken together, these results reveal that the GapA protein is a promising vaccine candidate that could be used to prevent streptococcosis in tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Changes of Microbiological Quality in Aquaculture tilapia (Oreochromis niloticus) After Irradiation Treatment

    International Nuclear Information System (INIS)

    Ali, H.A.S.

    2015-01-01

    The effect of different doses of gamma irradiation (1, 3 and 5 kGy) on the microbial flora of aquacultured Nile tilapia fish (Oreochromis niloticus) in cages inserted in Manzala Lake, Egypt, was investigated. These fish were fed on poultry by-product meal (PBM) in practical diets as replacement for fish meal protein in which herring fish meal (HFM) were replaced by PBM at ratio of 25 %, 50 %, 75% and 100% in the diet. Based on the results, it could be noticed that there was non-significant effect after partial (25, 50 and 75%) and complete replacement of fish meal protein by poultry by-product meal on the total bacterial count TBC, mould and yeast and Staphylococcus aureus counts (log cfu/g) of tilapia fish. Significant increases in the counts of Escherichia coli, Enterobacteriaceae and Enterobacter aerogenes were recorded, specially at the high levels of replacement (75 and 100%). Concerning the effect of gamma irradiation on fish samples, it could be observed that gamma irradiation with the doses 1,3 and 5 kGy significantly reduced TBC, mould and yeast, S. aureus. E. coli, Enterobacter aerogenes and Enterobacteriaceae counts of all treatments which reached undetectable values by using gamma irradiation doses of 3 and 5 kGy. From the present results, it could be concluded that using poultry by-product meal (PBM) in diets for Nile tilapia as replacement for fish meal protein supplied by herring fish meal (HFM) in the diet (to reduce feeding economic cost) significantly increase the log count of Enterobacteriaceae, Escherichia coli and Enterobacter aerogenes. However using gamma irradiation significantly reduced these counts which were undetectable using 3 and 5 kGy. It could be concluded that using gamma irradiation with dose 3 kGy can improve the hygienic quality of aquacultured Nile tilapia.

  14. Evidence of vertical transmission and tissue tropism of Streptococcosis from naturally infected red tilapia (Oreochromis spp.

    Directory of Open Access Journals (Sweden)

    Padmaja Jayaprasad Pradeep

    2016-05-01

    Full Text Available Streptococcosis is a highly problematic disease in the aquaculture of freshwater fishes, especially for tilapia. The possibility of vertical transmission of streptococcosis and the pattern of tissue tropism of this pathogen in various organs was examined in red tilapia (Oreochromis sp.. Healthy broodstock without any clinical signs of Streptococcus spp. were selected from a farm earlier reported to have the disease and a total of 10 pairs were forced spawned to provide samples of gametes and progeny for pathogen testing. A colorimetric LAMP assay was used to confirm whether the bacterial pathogens Streptococcus. agalactiae and Streptococcus. iniae was present in samples of milt, unfertilized eggs, fertilized eggs, and offspring at various stages of development, as well as internal organs of broodstock (reproductive organs, gill, liver, spleen, kidney and brain as well as samples of water from culture systems. The majority of samples of milt (9/10 and unfertilized eggs (7/10 collected from the broodstock were infected with S. iniae at the time of spawning and was transmitted to all of their offspring. Nevertheless, when the same samples of gametes were analyzed for S. agalactiae, they were all found to be negative but the pathogen was found to be present in some 10-day-old larval offspring (4/10. However, when the pathogenic presence was analyzed from the reproductive organs of the parents, both S. agalactiae (11/20 and S. iniae (18/20 bacterium were common. Although, all broodstock were asymptomatic, almost all broodstock harboured the bacteria in many organs. Confirmation of vertical transmission of streptococcosis in tilapia means that intergenerational break cannot be used as a reliable and simple means of reducing or eliminating the prevalence of these difficult pathogens in aquaculture stock. Keywords: Tilapia, Vertical transmission, Specific pathogen free, Streptococcus, Tissue tropism

  15. Effects of acclimation salinity on the expression of selenoproteins in the tilapia, Oreochromis mossambicus

    Science.gov (United States)

    Seale, Lucia A.; Gilman, Christy L.; Moorman, Benjamin P.; Berry, Marla J.; Grau, E. Gordon; Seale, Andre P.

    2014-01-01

    Selenoproteins are ubiquitously expressed, act on a variety of physiological redox-related processes, and are mostly regulated by selenium levels in animals. To date, the expression of most selenoproteins has not been verified in euryhaline fish models. The Mozambique tilapia, Oreochromis mossambicus, a euryhaline cichlid fish, has a high tolerance for changes in salinity and survives in fresh water (FW) and seawater (SW) environments which differ greatly in selenium availability. In the present study, we searched EST databases for cichlid selenoprotein mRNAs and screened for their differential expression in FW and SW-acclimated tilapia. The expression of mRNAs encoding iodothyronine deiodinases 1, 2 and 3 (Dio1, Dio2, Dio3), Fep15, glutathione peroxidase 2, selenoproteins J, K, L, M, P, S, and W, was measured in the brain, eye, gill, kidney, liver, pituitary, muscle, and intraperitoneal white adipose tissue. Gene expression of selenophosphate synthetase 1, Secp43, and selenocysteine lyase, factors involved in selenoprotein synthesis or in selenium metabolism, were also measured. The highest variation in selenoprotein and synthesis factor mRNA expression between FW- and SW-acclimated fish was found in gill and kidney. While the branchial expression of Dio3 was increased upon transferring tilapia from SW to FW, the inverse effect was observed when fish were transferred from FW to SW. Protein content of Dio3 was higher in fish acclimated to FW than in those acclimated to SW. Together, these results outline tissue distribution of selenoproteins in FW and SW-acclimated tilapia, and indicate that at least Dio3 expression is regulated by environmental salinity. PMID:24854764

  16. Population dynamics and ecology of Tilapia rendalli in Lago Sauce (Peru)

    Energy Technology Data Exchange (ETDEWEB)

    Wosnitza-Mendo, C.

    1980-01-01

    This is a practical contribution to development aid in Peru. It was to provide a basis for farming of Lago Sauce and similar lakes and introduce young Peruvian fishery biologists to practical and theoretical work with populations of freshwater fish. Various methods of biomass determination have been compared in order to find out why only small specimens of Tilapia rendalli have been caught and what ichthyobiomass was in the lake.

  17. Tilapia (Oreochromis mossambicus) brain cells respond to hyperosmotic challenge by inducing myo-inositol biosynthesis

    Science.gov (United States)

    Gardell, Alison M.; Yang, Jun; Sacchi, Romina; Fangue, Nann A.; Hammock, Bruce D.; Kültz, Dietmar

    2013-01-01

    SUMMARY This study aimed to determine the regulation of the de novo myo-inositol biosynthetic (MIB) pathway in Mozambique tilapia (Oreochromis mossambicus) brain following acute (25 ppt) and chronic (30, 60 and 90 ppt) salinity acclimations. The MIB pathway plays an important role in accumulating the compatible osmolyte, myo-inositol, in cells in response to hyperosmotic challenge and consists of two enzymes, myo-inositol phosphate synthase and inositol monophosphatase. In tilapia brain, MIB enzyme transcriptional regulation was found to robustly increase in a time (acute acclimation) or dose (chronic acclimation) dependent manner. Blood plasma osmolality and Na+ and Cl− concentrations were also measured and significantly increased in response to both acute and chronic salinity challenges. Interestingly, highly significant positive correlations were found between MIB enzyme mRNA and blood plasma osmolality in both acute and chronic salinity acclimations. Additionally, a mass spectrometry assay was established and used to quantify total myo-inositol concentration in tilapia brain, which closely mirrored the hyperosmotic MIB pathway induction. Thus, myo-inositol is a major compatible osmolyte that is accumulated in brain cells when exposed to acute and chronic hyperosmotic challenge. These data show that the MIB pathway is highly induced in response to environmental salinity challenge in tilapia brain and that this induction is likely prompted by increases in blood plasma osmolality. Because the MIB pathway uses glucose-6-phosphate as a substrate and large amounts of myo-inositol are being synthesized, our data also illustrate that the MIB pathway likely contributes to the high energetic demand posed by salinity challenge. PMID:24072790

  18. Accumulation and elimination of radioactive phosphorus (32P) in some organs of the Tilapia Nilotica

    International Nuclear Information System (INIS)

    Banico, M.P.T.

    1989-01-01

    The rate of accumulation and elimination of 32 P was measured in five organs, i.e., brain, bone, heart, muscle and small intestines of the Tilapia nilotica at 19 0 C or 28 0 C. There was a faster rate of uptake at 28 0 C, with the small intestines having the highest concentration of radioactive material. Elimination rates, however, indicate that bone retains 32 P longest. (Auth.). 10 refs.; 2 figs

  19. High rates of intestinal bicarbonate secretion in seawater tilapia (Oreochromis mossambicus).

    Science.gov (United States)

    Ruiz-Jarabo, I; Gregório, S F; Gaetano, P; Trischitta, F; Fuentes, J

    2017-05-01

    Osmoregulation in fish is a complex process that requires the orchestrated cooperation of many tissues. In fish facing hyperosmotic environments, the intestinal absorption of some monovalent ions and the secretion of bicarbonate are key processes to favor water absorption. In the present study, we showed that bicarbonate levels in the intestinal fluid are several fold higher in seawater than in freshwater acclimated tilapia (Oreochromis mossambicus). In addition, we analyzed gene expression of the main molecular mechanisms involved in HCO 3 - movements i.e. slc26a6, slc26a3, slc4a4 and v-type H-ATPase sub C in the intestine of tilapia acclimated to both seawater and freshwater. Our results show an anterior/posterior functional regionalization of the intestine in tilapia in terms of expression patterns, which is affected by environmental salinity mostly in the anterior and mid intestine. Analysis of bicarbonate secretion using pH-Stat in tissues mounted in Ussing chambers reveals high rates of bicarbonate secretion in tilapia acclimated to seawater from anterior intestine to rectum ranging between ~900 and ~1700nmolHCO 3 - cm -2 h -1 . However, a relationship between the expression of slc26a6, slc26a3, slc4a4 and the rate of bicarbonate secretion seems to be compromised in the rectum. In this region, the low expression of the bicarbonate transporters could not explain the high bicarbonate secretion rates here described. However, we postulate that the elevated v-type H-ATPase mRNA expression in the rectum could be involved in this process. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Hormonal regulation of aquaporin 3: opposing actions of prolactin and cortisol in tilapia gill.

    Science.gov (United States)

    Breves, Jason P; Inokuchi, Mayu; Yamaguchi, Yoko; Seale, Andre P; Hunt, Bethany L; Watanabe, Soichi; Lerner, Darren T; Kaneko, Toyoji; Grau, E Gordon

    2016-09-01

    Aquaporins (Aqps) are expressed within key osmoregulatory tissues where they mediate the movement of water and selected solutes across cell membranes. We leveraged the functional plasticity of Mozambique tilapia (Oreochromis mossambicus) gill epithelium to examine how Aqp3, an aquaglyceroporin, is regulated in response to osmoregulatory demands. Particular attention was paid to the actions of critical osmoregulatory hormones, namely, prolactin (Prl), growth hormone and cortisol. Branchial aqp3 mRNA levels were modulated following changes in environmental salinity, with enhanced aqp3 mRNA expression upon transfer from seawater to freshwater (FW). Accordingly, extensive Aqp3 immunoreactivity was localized to cell membranes of branchial epithelium in FW-acclimated animals. Upon transferring hypophysectomized tilapia to FW, we identified that a pituitary factor(s) is required for Aqp3 expression in FW. Replacement with ovine Prl (oPrl) was sufficient to stimulate Aqp3 expression in hypophysectomized animals held in FW, an effect blocked by coinjection with cortisol. Both oPrl and native tilapia Prls (tPrl177 and tPrl188) stimulated aqp3 in incubated gill filaments in a concentration-related manner. Consistent with in vivo responses, coincubation with cortisol blocked oPrl-stimulated aqp3 expression in vitro Our data indicate that Prl and cortisol act directly upon branchial epithelium to regulate Aqp3 in tilapia. Thus, within the context of the diverse actions of Prl on hydromineral balance in vertebrates, we define a new role for Prl as a regulator of Aqp expression. © 2016 Society for Endocrinology.

  1. Salmonella Weltevreden in integrated and non-integrated tilapia aquaculture systems in Guangdong, China.

    Science.gov (United States)

    Li, Kang; Petersen, Gitte; Barco, Lisa; Hvidtfeldt, Kristian; Liu, Liping; Dalsgaard, Anders

    2017-08-01

    Integrated tilapia-pig farming, which uses manure from pigs as fertilizers in fish pond, is a traditional and common production system practised by small-scale farmers in South-east Asia. Although such systems may be environmentally sustainable, they also pose potential food safety hazards including transmission of faecal zoonotic pathogens and accumulation of antimicrobial and other chemical residues. This study aimed to determine differences in occurrence and characteristics of Salmonella spp. isolated from tilapia-pig and non-integrated aquaculture systems in Guangdong province, China. A total of 77 samples (9 pig feed, 19 fish feed, 9 pig faeces, 20 fish mucus and 20 fish intestine) from 10 tilapia-pig ponds and 10 non-integrated ponds were analysed. Salmonella spp. was found in fish mucus (20.0%), fish intestine (40.0%) and pig faeces (11.1%) from integrated ponds, and from fish mucus (40.0%) and fish intestine (40.0%) from non-integrated ponds. S. Weltevreden (76.5%) was by far the most common serovar showing limited antimicrobial resistance. One pig faeces sample contained S. Typhimurium whereas feed samples were found free of Salmonella spp.. DNA fingerprinting by the PFGE method showed a clonal relationship of S. Weltevreden which was supported by similar antimicrobial resistance patterns (sulfamethoxazole and trimethoprim resistance) as well as most isolates harbouring a 147-kb sized plasmid. The common finding of S. Weltevreden in both tilapia production systems indicates that this serovar may have a different ecology and increased survival in aquaculture environments in comparison with other Salmonella serovars. Further in vivo studies of the ecology of S. Weltevreden in aquaculture environments are needed. Copyright © 2017. Published by Elsevier Ltd.

  2. Digestibility and performance of juvenile Nile tilapia fed with diets containing forage palm

    Directory of Open Access Journals (Sweden)

    Hannah Bandeira Thame Daniel

    2016-09-01

    Full Text Available Supplying the nutritional needs of animals in an economical way is essential to the success of any type of production. The forage palm is a cactaceae well-adapted to semiarid regions and commonly used in the feeding of ruminants. However, studies assessing its use in fishes are scarce. We aimed to evaluate the digestibility of bran from five different forage palm cultivars (Opuntia fícus in juvenile Nile tilapia and the development of juveniles when receiving increasing levels of the cultivar with the best apparent digestibility coefficient of crude protein (ADCCP (75.2%. We used 90 masculinized juvenile Nile tilapia (with an average weight of 6.02 ± 0.65 g in the digestibility experiment to determine the apparent digestibility coefficients of dry matter (ADCDM, crude energy (ADCCP, and crude protein of the cultivars (Orelha de onça, Miúda, Gigante, Comum, and IPA 20. The experimental design was completely randomized (CRD with five treatments and three repetitions. In the development experiment, 300 masculinized juvenile Nile tilapia (with average weight of 1.39 ± 0.12 g received feed with different inclusion levels (0, 72, 144, and 216 g Kg-1 of IPA 20 palm bran in a CRD with four treatments and five repetitions. We observed significant differences (P < 0.05 for ADCDM and ADCCP between the treatments. The cultivars that presented the highest ADCDM were IPA 20 (41.75%, Orelha de onça (36.41%, and Gigante (32.59%. For ADCCP, the best cultivar was IPA 20 with 75.2%, followed by Orelha de onça (61.5%, and Miúda (56.1%. As for the performance, the inclusion of IPA 20 palm bran at a rate of 113 g/kg-1 provided the best values in terms of weight gain and final weight in juvenile Nile tilapia.

  3. Attempts to sterilize Tilapia zillii by gamma irradiation for introduction into an ecosystem

    International Nuclear Information System (INIS)

    Andersen, A.C.; Momeni, M.H.; Nelson, S.G.; Yeo, R.R.

    1975-01-01

    Tilapia zillii, a cichlid fish from northern Africa, was introduced into Florida, Alabama, Arizona, and California for aquatic weed control. A study was conducted to determine if the germ cells of the fish could be selectively destroyed by ionizing radiation in doses below the lethal range in order to obviate the potential ecological problems associated with proliferation of an exotic fish species. No demonstrable effect on the gonads was shown by gamma doses up to 3300 R

  4. Quantification of intestinal bacteria, operating cost and performance of fingerlings Nile tilapia subjected to probiotics

    Directory of Open Access Journals (Sweden)

    Nilton Garcia-Marengoni

    2015-05-01

    Full Text Available The use of microorganisms of the genus Bacillus in aquaculture is a nutritional management practice that is rapidly expanding in regions with intensive fish farming. This study aimed to quantify the total bacteria and total coliforms from the intestinal microbiota and estimate the partial operating costs and growth performance of Nile tilapia (Oreochromis niloticus of the GIFT strain. A total of 1,200 post-larvae (24.7 ± 0.50 mg were distributed into 24 aquaria (0.03-m³ capacity within a completely randomized design in 2 x 3 factorial (phase x bacteria, with four replications. Each aquarium, containing 50 post-larvae (sex reversal phase or 30 fish (fingerlings phase, it was considered to be an experimental unit, consisting of three treatments (diet+Bacillus subtilis C-3102, diet+Bacillus cereus var. toyoi and diet without probiotic addition. The quantification of the total bacteria and total coliforms of the intestinal microbiota of tilapia were influenced (P 0.05 by adding probiotics in the diets and no effect of the interaction between phase and bacteria was observed. The weight gain, average daily weight gain, specific growth rate and apparent feed conversion were not affected (P > 0.05 by inclusion of probiotics as part of the diets. The inclusion of B. subtilis and B. cereus as part of diets for Nile tilapia promotes intestinal colonization and improves the survival rate without negatively influencing the feed intake, total biomass, gross revenue and partial operating costs and net revenue. Therefore it recommends the use of these probiotics to growth of tilapia fingerlings Nile, GIFT strain.

  5. Survival, Growth and Reproduction of Non-Native Nile Tilapia II: Fundamental Niche Projections and Invasion Potential in the Northern Gulf of Mexico

    Science.gov (United States)

    2012-07-27

    tilapia [71], the expectation is that pH will decrease due to ocean acidification [72,73]. Nile tilapia are tolerant of a wide pH range but juvenile...PLoS ONE | www.plosone.org 5 July 2012 | Volume 7 | Issue 7 | e41580 plasticity of future generations [79,80]. In Schofield et al.’s [22] summer

  6. Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics

    CSIR Research Space (South Africa)

    Zengeya, TA

    2013-07-01

    Full Text Available tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic...

  7. Effects of addition of tilapia Oreochromis niloticus and substrates for periphyton developments on pond ecology and production in C/N-controlled freshwater prawn Macrobrachium rosenbergii farming systems

    NARCIS (Netherlands)

    Asaduzzaman, M.; Wahab, M.A.; Verdegem, M.C.J.; Benerjee, S.; Akter, T.; Hasan, M.M.; Azim, M.E.

    2009-01-01

    The present research investigated the effect of addition of tilapia and substrates for periphyton development on pond ecology, production and economic performances in C/N controlled freshwater prawn farming system. The absence and presence (0 and 0.5 individual m- 2) of tilapia were investigated in

  8. Production of hydrolysate from processed Nile tilapia (Oreochromis niloticus residues and assessment of its antioxidant activity

    Directory of Open Access Journals (Sweden)

    Daniela Miotto BERNARDI

    2016-01-01

    Full Text Available Abstract The objective of this work was to produce protein hydrolysates from by-products of the Nile tilapia fileting process, and to assess the effects of different hydrolysis times on the antioxidant activity of the hydrolysed animal-based protein, in free form and incorporated into a food matrix. Gutted tilapia heads and carcasses were hydrolysed by Alcalase® for different hydrolysis times producing six hydrolysates. The protein content, degree of hydrolysis, reverse-phase high-performance liquid chromatography, and antioxidant activity by the ORAC, FRAP and TEAC methods were analysed. Three mini-hamburger formulations were produced and the lipidic oxidation of mini-hamburger was determined by TBARS. The protein contained in the residue was completely recovered in the process. The hydrolysates varied in their degree of hydrolysis, but presented similar levels of antioxidant activity. In the mini-hamburgers the hydrolysate was capable of delaying oxidation after 7 days of storage. Hydrolysis of tilapia processing by-products produced peptides may be used in the formulation of functional foods.

  9. Integrated Multi-Trophic Recirculating Aquaculture System for Nile Tilapia (Oreochlomis niloticus

    Directory of Open Access Journals (Sweden)

    Puchong Sri-uam

    2016-06-01

    Full Text Available Three densities of the sex-reversed male Nile tilapia, Oreochromis niloticus (20, 25, 50 fish/m3 were cultivated in an integrated multi-trophic recirculating aquaculture system (IMRAS that involves the ecological relationship between several living organisms, i.e., phytoplankton, zooplankton, and aquatic plants. The results indicated that, by providing proper interdependency between various species of living organisms, the concentrations of ammonia, nitrite, nitrate, and phosphate in the system were maintained below dangerous levels for Nile tilapia throughout the cultivation period. The highest wet weight productivity of Nile tilapia of 11 ± 1 kg was achieved at a fish density of 50 fish/m3. The aquatic plants in the treatment tank could effectively uptake the unwanted nitrogen (N and phosphorus (P compounds with the highest removal efficiencies of 9.52% and 11.4%, respectively. The uptake rates of nitrogen and phosphorus by aquatic plants could be ranked from high to low as: Egeria densa > Ceratophyllum demersum > Vallisneria spiralis and Vallisneria americana > Hygrophila difformis. The remaining N was further degraded through nitrification process, whereas the remaining P could well precipitate in the soil sediment in the treatment tank.

  10. Seasonal influence on the hematological parameters in cultured Nile tilapia from southern Brazil

    Directory of Open Access Journals (Sweden)

    GT. Jerônimo

    Full Text Available This study evaluated seasonality in hematological parameters of Nile tilapia cultured in the state of Santa Catarina, southern Brazil. A total of 240 fish were examined during four seasons between April 2007 and March 2008 in three different fish farms. After being anesthetised in a benzocaine solution, blood samples were withdrawn into syringes containing a drop of 10% EDTA for hematological analysis. The results were compared between fish farms and seasons, which are well delimited in southern Brazil. In a traditional fish farm in Joinville in the summer, there was an increase in the percentage of hematocrit and in the red blood cell count. The highest values of total leukocytes were found in fish from fee-fishing in Blumenau in the autumn while the lowest values occurred in those from swine consorted system in Ituporanga in the summer. Thrombocytosis was observed in the autumn, and lymphocytosis was found in both the autumn and winter in tilapia from all fish farms investigated. Neutrophilia was only observed in winter and autumn in fish from Blumenau and Ituporanga. This work demonstrated the influence of seasonality and the handling characteristics of each fish farm on certain hematological parameters in Nile tilapia.

  11. Effects of herbs and spice on health status of tilapia (Oreochromis mossambicus challenged with Streptococcus iniae

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    Nejdet Gültepe

    2014-01-01

    Full Text Available Effects of different herbal extracts on the growth and immune defense of fish were researched in the last decade. The aim of this study was to determine the dietary effects of thyme (Thymus vulgaris, rosemary (Rosmarinus officinalis and fenugreek (Trigonella foenum graecum as a feed additive on haematology, innate immune response, and disease resistance of tilapia (Oreochromis mossambicus. In total 228 healthy fish tilapia were divided into four groups (57 fish in one group and fed diets supplemented with thyme, rosemary and fenugreek at levels of 1%, respectively; fish in the control group were fed diet without any spices. Fish were fed ad libitum three times a day for 45 days. All fish of the experimental groups significantly (P P P > 0.05 changed during the whole experiment. After 45 days of feeding, fish were injected intraperitoneally with 100 μl of Streptococcus iniae (8 × 108 colony forming unit. The cumulative mortality was 22%, 27% and 31% in fish receiving diets supplemented with 1% thyme, rosemary and fenugreek, respectively, compared to 61% mortality in the control group. The results indicate that all three supplements used improved the haematological status, non-specific immune response and disease resistance of tilapia against S. iniae; this is the first similar study.

  12. Digestibility and pricing of Chlorella sorokiniana meal for use in tilapia feeds

    Directory of Open Access Journals (Sweden)

    Rafael Simões Coelho Barone

    Full Text Available ABSTRACT: Several microalgae contain in excess of 50 % crude protein with amino acid profile comparable to that of fish meal. In addition, high polyunsaturated fatty acid contents encourage their use in animal feeding and nutrition, particularly in the formulation and processing of aquafeeds. This study aims at estimating the feasibility of Chlorella meal as feed ingredient for the feeding and nutrition of farmed tilapia based upon digestibility data. Juvenile tilapia were stocked in conical-bottomed tanks (200 L with superficial, continuous water flow, and fed to apparent satiation in three daily meals with a reference diet and a test diet containing 30 % lyophilized Chlorella sorokiniana added of an inert marker. Feces were collected overnight by sedimentation in refrigerated, plastic containers coupled to the tanks and analyzed for determination of chemical composition and inert marker contents to estimate apparent digestibility coefficients (ADCs of protein and energy of Chlorella meal; registered ADCs of Chlorella meal were 90.5 and 84.22, respectively. A pricing model considering the quantity of digestible nutrient was proposed based on ADCs of Chlorella and compared with the price of fishmeal (FM and soybean meal (SBM. The indicative prices to elicit the use of Chlorella as a protein source rather than FM or SBM for the feed and nutrition of tilapia were 2.65 USD kg−1 and 0.66 USD kg−1, respectively.

  13. Use of mathematical models in the study of bodily growth in GIFT strain Nile tilapia

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    Alda Lúcia de Lima Amancio

    Full Text Available The objective of this study was to evaluate the accuracy of five mathematical models (Gompertz, Logistic, Linear Hyperbolic, Quadratic and Quadratic Logarithmic to describe the growth curve of GIFT strain Nile tilapia, Oreochromis niloticus, and to characterize the growth trajectory of body parts. To do this, 1,000 fingerlings, with an initial weight of 2.4 g were placed into 20 brick tanks of 2 m³ each, at a density of 25 fish m-3, for 180 days. The animals were fed daily, using the protein levels and number of meals appropriate to each stage. Every two weeks 20 fish were randomly sampled, submitted to a fasting period of 48 h and then slaughtered by thermal shock, in order to determine the weight of the whole fish, the skin without scales, skinless fillets, heart, liver, gills and gastrointestinal tract. The Gompertz and Logistic models presented the best fit to the growth curve for live weight, fillet and skin, however the Logistic model underestimated the asymptotic weights. Therefore, to describe the growth curve in GIFT strain Nile tilapia, the Gompertz model is suggested. According to the parameters estimated by the Gompertz model, Nile tilapia reach the age for maximum growth of the fillet and skin before that of body weight. Among the organs studied, growth of the gastrointestinal tract and gills takes place earlier than that of the heart and liver.

  14. Phosphoglycerate kinase enhanced immunity of the whole cell of Streptococcus agalactiae in tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Wang, Yi-Ting; Huang, Hsing-Yen; Tsai, Ming-An; Wang, Pei-Chi; Jiang, Bo-Huang; Chen, Shih-Chu

    2014-12-01

    Streptococcus agalactiae is a Gram-positive bacterium and a severe aquaculture pathogen that can infect a wide range of warmwater fish species. The outer-surface proteins in bacterial pathogens play an important role in pathogenesis. We evaluated the immunogenicity of two of the identified surface proteins namely phosphoglycerate kinase (PGK) and ornithine carbamoyl-transferase (OCT). PGK and OCT were over-expressed and purified from Escherichia coli and used as the subunit vaccines in tilapia. Tilapia immunized with the S. agalactiae modified bacteria vaccine (whole cell preparations with recombinant PGK and OCT proteins) individually were tested for the efficacy. OCT and PGK combined with WC had a higher survival rate. A high-level protection and significant specific antibody responses against S. agalactiae challenge was observed upon the vaccinated tilapia with the purified PGK protein and S. agalactiae whole cells. The specific antibody titer against S. agalactiae antigen suggested that increased antibody titers were correlated with post-challenge survival rate. Il-1β expression profile was higher in PGK + WC-treated group. Tnf-α expression in the PGK + WC group was significantly increased. Taken together, our results suggested the combinations of recombinant protein and whole cell may elicit immune responses that reach greater protection than that of individual S. agalactiae components. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Nile tilapia Oreochromis niloticus as a food source in advanced life support systems: Initial considerations

    Science.gov (United States)

    Gonzales, John M.; Brown, Paul B.

    2006-01-01

    Maintenance of crew health is of paramount importance for long duration space missions. Weight loss, bone and calcium loss, increased exposure to radiation and oxidative stress are critical concerns that need to be alleviated. Tilapia are currently under evaluation as a source of food and their contribution to reducing waste in advanced life support systems (ALSS). The nutritional composition of tilapia whole bodies, fillet, and carcass residues were quantitatively determined. Carbon and nitrogen free-extract percentages were similar among whole body (53.76% and 6.96%, respectively), fillets (47.06% and 6.75%, respectively), and carcass (56.36% and 7.04%, respectively) whereas percentages of N, S, and protein were highest in fillet (13.34, 1.34, and 83.37%, respectively) than whole body (9.27, 0.62, and 57.97%, respectively) and carcass (7.70, 0.39, and 48.15%, respectively). Whole body and fillet meet and/or exceeded current nutritional recommendations for protein, vitamin D, ascorbic acid, and selenium for international space station missions. Whole body appears to be a better source of lipids and n-3 fatty acids, calcium, and phosphorous than fillet. Consuming whole fish appears to optimize equivalent system mass compared to consumption of fillets. Additional research is needed to determine nutritional composition of tilapia whole body, fillet, and carcass when fed waste residues possibly encountered in an ALSS.

  16. Extraction of high value added gelatin biopolymer from black tilapia (Oreochromis mossambicus) head bones

    Science.gov (United States)

    Sockalingam, K.; Abdullah, H. Z.

    2015-07-01

    Black tilapia (Oreochromis mossambicus) fish head bones were evaluated for its possibilities in extracting gelatin. Head bones were subjected to pre-treatment with 3% of hydrochloric acid (HCl) for demineralization before undergoes thermal extraction process. The raw head bones were characterized via Scanning Electron Microscopy (SEM) in order to investigate the external and internal surface morphology. SEM images also reveal the presence of collagen fiber with 1 µm diameter in the head bone. The black tilapia fish head bones yields 5.75 % of gelatin in wet weight basis, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw head bones and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The head bones gelatin shows high protein (10.55%) and ash (3.11 %) content with low moisture. This further proves the effectiveness of demineralization and extraction method used. The black tilapia fish head bones are found to be a prospective source of gelatin with good chemical and functional properties.

  17. Extraction of high value added gelatin biopolymer from black tilapia (Oreochromis mossambicus) head bones

    International Nuclear Information System (INIS)

    Sockalingam, K.; Abdullah, H. Z.

    2015-01-01

    Black tilapia (Oreochromis mossambicus) fish head bones were evaluated for its possibilities in extracting gelatin. Head bones were subjected to pre-treatment with 3% of hydrochloric acid (HCl) for demineralization before undergoes thermal extraction process. The raw head bones were characterized via Scanning Electron Microscopy (SEM) in order to investigate the external and internal surface morphology. SEM images also reveal the presence of collagen fiber with 1 µm diameter in the head bone. The black tilapia fish head bones yields 5.75 % of gelatin in wet weight basis, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw head bones and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The head bones gelatin shows high protein (10.55%) and ash (3.11 %) content with low moisture. This further proves the effectiveness of demineralization and extraction method used. The black tilapia fish head bones are found to be a prospective source of gelatin with good chemical and functional properties

  18. Assessing exposure risks for freshwater tilapia species posed by mercury and methylmercury.

    Science.gov (United States)

    Cheng, Yi-Hsien; Lin, Yi-Jun; You, Shu-Han; Yang, Ying-Fei; How, Chun Ming; Tseng, Yi-Ting; Chen, Wei-Yu; Liao, Chung-Min

    2016-08-01

    Waterborne and dietborne exposures of freshwater fish to mercury (Hg) in the forms of inorganic (Hg(II)) and organic (methylmercury or MeHg) affect their growth, development, and reproduction. However, an integrated mechanistic risk model framework to predict the impact of Hg(II)/MeHg on freshwater fish is lacking. Here, we integrated biokinetic, physiological and biogeographic data to calibrate and then establish key risk indices-hazardous quotient and exceedance risk-for freshwater tilapia species across geographic ranges of several major rivers in Taiwan. We found that Hg(II) burden was highest in kidney followed by gill, intestine, liver, blood, and muscle. Our results showed that Hg was less likely to pose mortality risk (mortality rate less than 5 %) for freshwater tilapia species. However, Hg is likely to pose the potential hazard to aquatic environments constrained by safety levels for aquatic organisms. Sensitivity analysis showed that amount of Hg accumulated in tilapia was most influenced by sediment uptake rate. Our approach opens up new possibilities for predicting future fish population health with the impacts of continued Hg exposure to provide information on which fish are deemed safe for human consumption.

  19. Irisin inhibition of growth hormone secretion in cultured tilapia pituitary cells.

    Science.gov (United States)

    Lian, Anji; Li, Xin; Jiang, Quan

    2017-01-05

    Irisin, the product of fibronectin type III domain-containing protein 5 (FNDC5) gene, is well-documented to be a regulator of energy metabolism. At present, not much is known about its biological function in non-mammalian species. In this study, a full-length tilapia FDNC5 was cloned and its tissue expression pattern has been confirmed. Based on the sequence obtained, we produced and purified recombinant irisin which could induce uncoupling protein 1 (UCP1) gene expression in tilapia hepatocytes. Further, the rabbit polyclonal irisin antiserum was produced and its specificity was confirmed by antiserum preabsorption. In tilapia pituitary cells, irisin inhibited growth hormone (GH) gene expression and secretion and triggered rapid phosphorylation of Akt, Erk1/2, and p38 MAPK. Furthermore, irisin-inhibited GH mRNA expression could be prevented by inhibiting PI3K/Akt, MEK1/2, and p38 MAPK, respectively. Apparently, fish irisin can act directly at the pituitary level to inhibit GH transcript expression via multiple signaling pathways. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Molecular cloning and gene expression of Foxl2 in the Nile tilapia, Oreochromis niloticus

    International Nuclear Information System (INIS)

    Wang Deshou; Kobayashi, Tohru; Zhou Linyan; Nagahama, Yoshitaka

    2004-01-01

    A Foxl2 cDNA was cloned from the Nile tilapia ovary by RT-PCR and subsequent RACE. Alignment of known Foxl2 sequences from vertebrates confirmed the conservation of the Foxl2 open reading frame and protein sequences, especially the forkhead domain and C-terminal region, while some homopolymeric runs of amino acids are found only in mammals but not in non-mammalian vertebrates. RT-PCR revealed that Foxl2 is expressed in the tilapia brain (B), pituitary (P), gill, and gonads (G), with the highest level of expression in the ovary, reflecting the involvement of Foxl2 in B-P-G axis. Northern blotting and in situ hybridization also revealed an evident sexual dimorphic expression pattern in the gonads. Foxl2 mRNA was mainly detected in the granulosa cells surrounding the oocytes. The ovarian expression of Foxl2 in tilapia begins early during the differentiation of the gonads and persists until adulthood, implying the involvement of Foxl2 in fish gonad differentiation and the maintenance of ovarian function

  1. Extraction of high value added gelatin biopolymer from black tilapia (Oreochromis mossambicus) head bones

    Energy Technology Data Exchange (ETDEWEB)

    Sockalingam, K., E-mail: gd130106@siswa.uthm.edu.my; Abdullah, H. Z., E-mail: hasan@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Black tilapia (Oreochromis mossambicus) fish head bones were evaluated for its possibilities in extracting gelatin. Head bones were subjected to pre-treatment with 3% of hydrochloric acid (HCl) for demineralization before undergoes thermal extraction process. The raw head bones were characterized via Scanning Electron Microscopy (SEM) in order to investigate the external and internal surface morphology. SEM images also reveal the presence of collagen fiber with 1 µm diameter in the head bone. The black tilapia fish head bones yields 5.75 % of gelatin in wet weight basis, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw head bones and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The head bones gelatin shows high protein (10.55%) and ash (3.11 %) content with low moisture. This further proves the effectiveness of demineralization and extraction method used. The black tilapia fish head bones are found to be a prospective source of gelatin with good chemical and functional properties.

  2. Marine Collagen Peptides from the Skin of Nile Tilapia (Oreochromis niloticus): Characterization and Wound Healing Evaluation.

    Science.gov (United States)

    Hu, Zhang; Yang, Ping; Zhou, Chunxia; Li, Sidong; Hong, Pengzhi

    2017-03-30

    Burns can cause tremendous economic problems associated with irreparable harm to patients and their families. To characterize marine collagen peptides (MCPs) from the skin of Nile tilapia ( Oreochromis niloticus ), molecular weight distribution and amino acid composition of MCPs were determined, and Fourier transform infrared spectroscopy (FTIR) was used to analyze the chemical structure. Meanwhile, to evaluate the wound healing activity, in vitro and in vivo experiments were carried out. The results showed that MCPs prepared from the skin of Nile tilapia by composite enzymatic hydrolysis were composed of polypeptides with different molecular weights and the contents of polypeptides with molecular weights of less than 5 kDa accounted for 99.14%. From the amino acid composition, the majority of residues, accounting for over 58% of the total residues in MCPs, were hydrophilic. FTIR indicated that the main molecular conformations inside MCPs were random coil. In vitro scratch assay showed that there were significant effects on the scratch closure by the treatment of MCPs with the concentration of 50.0 μg/mL. In the experiments of deep partial-thickness scald wound in rabbits, MCPs could enhance the process of wound healing. Therefore, MCPs from the skin of Nile tilapia ( O. niloticus ) have promising applications in wound care.

  3. Water Quality Improvement of Media Culture for Tilapia (Oreochromis niloticus) with Cleaner Production Method

    Science.gov (United States)

    Haeruddin; Supriharyono; Febrianto, S.

    2018-02-01

    The tilapia (Oreochromis niloticus), is known as a high adaptability and brackish water tolerance fish. This fish is also has a meat with high protein content, that ranges about 65 -75%. Generally the tilapia is cultured using a conventional system with high density. It is caused degradation of water quality of media culture, and finally increase mortality rate of fish cultured. The application of tilapia cultivation with cleaner production method by giving enzyme into the feed to upgrade the efficiency of feed utilization, presumed that could improve the water quality of cultivation media. It is due to the lower of feed and feces residues. Therefore the concentration of toxic compounds, such as ammonia, nitrite and sulfide, will be lower. The experiments were conducted for 35 days with a completely factorial randomized design. The first factor was the dosage of enzyme in the feed, consisting of 4 dosages, and the second factor was the duration of the test fish maintenance (5 weeks). Water quality variables examined included ammonia, nitrite and sulfide. The results showed that enzyme dosage had no significantly impact on ammonia, nitrite and sulfide concentrations in the test media culture. However, the feeding with enzyme in low dosage, resulted less concentration of ammonia, nitrite and sulfide than it was without enzyme). The duration of fish cultured has significantly effect on the concentration of ammonia, nitrite and sulfide in the test media. While it is no significantly correlation between dosage and duration of maintenance.

  4. Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn

    Directory of Open Access Journals (Sweden)

    William Franco Carneiro

    2017-09-01

    Full Text Available The objective was to determine the requirement of digestible protein (DP for Nile tilapia fed with diets based on soybean meal and corn. Two hundred Nile tilapia juveniles, sexually reversed, were used for a trial period of 100 days. The animals were distributed in 20 boxes of 1000 L-1 in a random design with five treatments and four replications, the boxes were connected to a water recirculation system. Five isoenergetic diets were tested with different levels of digestible protein (DP: 20, 25, 30, 35 and 40%. At the end of the experimental period were evaluated the zootechnical performance data. A quadratic effect (p < 0.05 was shown to parameters of final weight, weight gain, final length, fillet yield and visceral fat with the best points that ranged from 28.3 to 29.9% of DP. The largest area of hepatocytes was found to the lowest levels of DP in the diet (20 and 25% compared to the other levels, which were similar. Thus, Nile tilapia has adequate performance for the consumption of diets based on soybean and corn meal and the recommended level is 28.3% of PD in these conditions.

  5. Modeling traceability information and functionality requirement in export-oriented tilapia chain.

    Science.gov (United States)

    Zhang, Xiaoshuan; Feng, Jianying; Xu, Mark; Hu, Jinyou

    2011-05-01

    Tilapia has been named as the 'food fish of the 21st century' and has become the most important farmed fish. China is the world leader in tilapia production and export. Identifying information and functional requirements is critical in developing an efficient traceability system because traceability has become a fundamental prerequisite for exporting aquaculture products. This paper examines the export-oriented tilapia chains and information flow in the chains, and identifies the key actors, information requirements and information-capturing points. Unified Modeling Language (UML) technology is adopted to describe the information and functionality requirement for chain traceability. The barriers of traceability system adoption are also identified. The results show that the traceability data consist of four categories that must be recorded by each link in the chain. The functionality requirement is classified into four categories from the fundamental information record to decisive quality control; the top three barriers to the traceability system adoption are: high costs of implementing the system, lack of experienced and professional staff; and low level of government involvement and support. Copyright © 2011 Society of Chemical Industry.

  6. Antioxidant activities of red tilapia (Oreochromis niloticus) protein hydrolysates as influenced by thermolysin and alcalase

    Science.gov (United States)

    Daud, Nur'Aliah; Babji, Abdul Salam; Yusop, Salma Mohamad

    2013-11-01

    The hydrolysis process was performed on fish meat from Red Tilapia (Oreochromis niloticus) by enzymes thermolysin and alcalase under optimum conditions. The hydrolysis was performed from 0 - 4 hours at 37°C. Hydrolysates after 2 hours incubation with thermolysin and alcalase had degree of hydrolysis of 76.29 % and 63.49 %, respectively. The freeze dried protein hydrolysate was tested for peptide content and characterized with respect to amino acid composition. The result of increased peptide content in Red Tilapia (O. Niloticus) hydrolysates obtained was directly proportional to the increase activities of different proteolytic enzymes. The result of amino acid composition showed that the sample used contained abundant Gly, Ala, Asp, Glu, Lys and Leu in residues or peptide sequences. Both enzymatic hydrolysates were tested for anti-oxidant activity with DPPH and ABTS assay. Alcalase yielded higher anti-oxidative activity than Thermolysin hydrolysates after 1 hour incubation, but both enzymes hydrolysates showed a significant decrease of anti-oxidant activity after 2 hours of incubation. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient in functional foods to reduce oxidation stress caused by accumulated free radicals.

  7. FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

    Directory of Open Access Journals (Sweden)

    EDUARDO ARRUDA TEIXEIRA LANNA

    2016-01-01

    Full Text Available The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus fed low-protein diets (29% crude protein supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine. Sex-reversed Nile tilapia (240 of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day. Six replications were conducted on separate experimental units comprising eight fishes each. The fish were maintained in 30 130-L aquariums, each equipped with individual water supply and controlled temperature and aeration. Fish were fed identical quantities among all treatments over a period of 30 days. Performance parameters, feed conversion efficiency, body composition, daily protein and fat deposition rates, and nitrogen retention efficiency were evaluated. Increased feeding frequency affected neither performance parameters nor body composition. Values for protein and fat deposition rates and nitrogen retention efficiency were significantly lower in fish fed twice daily than in those fed five times daily. Fish subjected to other feeding frequencies yielded intermediate values without any significant differences. The minimum feeding frequency of Nile tilapia fingerlings fed a low-protein ration supplemented with commercial amino acids is three times a day, owing to increased protein deposition rates and nitrogen retention efficiency.

  8. Tilapia africana en el Lago de Nicaragua: ecosistema en transición.

    Directory of Open Access Journals (Sweden)

    Jeffrey K. McCrary

    1998-10-01

    Full Text Available Los grandes lagos de Nicaragua, son comparables con el sistema de grandes lagos africanos. Contienen una gran diversidad de peces, incluyendo varios peces endémicos de la familia Cichlidae. La captura de peces en el Lago de Cocibolca, estandarizada en 100 metros de red, promedió 4.34 kilogramos en el área de Ometepe, en donde la tilapia constituyó el 1.5 % del peso total de la captura. Este promedio fue de 0.80 kilogramos en la costa septentrional, donde la tilapia constituyó 54% del peso total de la captura. Un estudio ruso efectuado en 1983 y desarrollado en todo el Lago, demostró que el promedio era de 4.66 kilogramos. Los autores del presente artículo recomiendan que en el Lago Cocibolca se implemente un plan de manejo adecuado para controlar la población de tilapia y rescatar un ecosistema en peligro de colapso

  9. The use of crude extracts from traditional medicinal plants to eliminate Trichodina sp. in tilapia (Oreochromis niloticus fingerlings

    Directory of Open Access Journals (Sweden)

    Chanagun Chitmanat

    2005-02-01

    Full Text Available The treatment for ectoparasitic diseases in freshwater fish with formalin seems at present to be ineffective. For this reason it is evidently a useless cost. In addition, formalin possibly leaves toxic residues in fish flesh and in the environment which are eventually harmful to consumers. The alternative way to solve this problem is to use traditional medicinal plants instead. The purpose of this research is to determine the possibility of using garlic (Allium sativum and Indian almond (Terminalia catappa as optional chemicals to treat fish ectoparasites, Trichodina sp. The results showed that crude extracts of either garlic or Indian almond at 800 mg/l significantly (P < 0.05 eliminated Trichodina sp. infections in tilapia (average weight 3.62±0.06 g each. To evaluate the acute toxicity of these products to the host fish, groups of 20 tilapia (same size as abovewere exposed to 3 concentrations of each product for 96 h. Mortality was then determined. The 2 h LC50 for tilapia exposed to crude extract of garlic was 2,259.44 mg/L while the 16 h LC50 for tilapia exposed to Indian almond extract was 46,665.94 mg/L. This information is the beneficial and fundamental knowledge to develop guidelines to reduce the use of chemicals and antibiotics in freshwater fish culture businesses. The research is underway to determine the long-term effect of Indian almond and garlic to tilapia, if any.

  10. DNA profiling of Tilapia guinasana, a species endemic to a single sinkhole, to determine the genetic divergence between color forms.

    Science.gov (United States)

    Nxomani, C; Ribbink, A J; Kirby, R

    1999-06-01

    Northwestern South Africa and Namibia contain a number of sinkholes in the dolomitic rock formations found in this area. These contain isolated populations of Tilapia. Most contain Tilapia sparmanii, but the one in Namibia, Guinas, is of particular interest as it contains the endemic species, Tilapia guinasana, which exhibits none sex-limited polychromatisms, which is unique for Tilapia. This sinkhole is under environmental threat, particularly as a result of being a recreational diving site. This study, using randomly amplified polymorphic DNA sequences (RAPDs), when analyzed using analysis of variance (ANOVA), shows that the colour forms of Tilapia guinasana are genetically distinct. This confirms previous evidence that assortative mating between color forms takes place. The various possible hypotheses for the occurrence and genetic stability of the color polymorphism are discussed. Further, a new hypothesis is put forward based on a need to maximize outbreeding in fully isolated population with no possibility of increase in size above the maximum and limited carrying capacity of the sinkhole.

  11. Polyculture Engineering technology of larasati red tilapia (Oreochromis niloticus) and white shrimp (Litopenaeus vannamei) based for protease enzyme

    Science.gov (United States)

    Samidjan, I.; Rachmawati, D.

    2018-04-01

    The objective is polyculture technology of red tilapia larasati fish and white shrimp with different combinations density. The material is saline red tilapia larasati 3.29 ± 0.018 g and white shrimp with initial weight 1.39 ± 0.025 g. Seeds are density of red tilapia larasati larvae 5 and 10 larvae / m2 fish. And white shrimp 5 larvae / m2 and 10 larvae / m2. An artificial feed used enzyme dose of 2.25 g / kg. The experimental using complete randomized design 4 treatments and 3 replications that is given seeds 5 larvae / m2 larvae red tilapia larasati and given 5 larvae / m2 white shrimp (A), 5 larvae / m2 red tilapia) and 10 m2 / m2 of white shrimp (B), 10 m2 larvae and 5 m2 white shrimp (C), 10 m2 larvae and 10 m2 white shrimp (D)). The data were growth of absolute weight, survival rate, FCR, and water quality data (temperature, salinity, pH, O2, NO2, NH3). Data were analyzed of variance (F test). The results showed significantly effect (P shrimp (25.25 ± 0.95 g).

  12. Effects of tartary buckwheat polysaccharide combined with nisin edible coating on the storage quality of tilapia (Oreochromis niloticus) fillets.

    Science.gov (United States)

    Wang, Fengping; Zhang, Huijun; Jin, Wengang; Li, Lirong

    2018-06-01

    To investigate the effect of tartary buckwheat polysaccharide (TBP) combined with nisin edible coatings on the preservation of tilapia (Oreochromis niloticus) fillets, fillets were dip treated with different concentrations of TBP (5, 10 and 15 g kg -1 ) combined with nisin and stored at 4 °C for 12 days. The pH values, thiobarbituric acid contents, total volatile base nitrogen (TVB-N) content, total viable count (TVC), surface colors, textures and sensory properties of the tilapia fillets at storage were all periodically investigated. TBP combined with nisin-treated groups significantly improved the bacteriological, physicochemical, and sensory characteristics of the tilapia fillets to a greater extent compared to the control group and presented better quality preservation effects than nisin coating alone. Based on the limits of the TVB-N, TVC and sensory scores, the shelf life of the control tilapia fillets was 4 days, whereas that for nisin with TBP-coated fillets was 8-10 days. Edible coatings made from TBP combined with nisin are suitable for maintaining qualities and enhancing the shelf lives of tilapia fillets stored at 4 °C. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Irradiation and postirradiation storage at 2 +/- 2 degrees C of tilapia (Tilapia nilotica X T. aurea) and Spanish mackeral (Scomberomorus commerson): sensory and microbial assessment

    International Nuclear Information System (INIS)

    Abu-Tarboush, H.M.; Al-Kahtani, H.A.; Atia, M.; Abou-Arab, A.A.; Bajaber, A.S.; El-Mojaddidi, M.A.

    1996-01-01

    Tilapia (low-fat farm fish, Tilapia nilotica X T. aurea) and Spanish mackerel (high-fat seawater fish, Scomberomorus commerson) were subjected to gamma irradiation doses of 1.5, 3.0, 4.5, 6.0, and 10.0 kGy by using a semicommercial gamma irradiator. The irradiated and unirradiated (controls) fish were stored at 2 +/- 2 degrees C and samples were drawn at day 0, 4, 8, 12, 16, and 20 for sensory evaluation and microbiological analysis. Doses of 3.0 and/or 4.5 kGy extended the sensory acceptability (appearance, odor, texture, taste) and the microbial quality (total count and coliforms) by 8 days compared to the unirradiated controls. Hydrogen sulfide-producing bacteria were low in both types of fish and a dose of 1.5 kGy kept this flora at low levels throughout the storage period. Moreover, this dose level was also sufficient to eliminate Salmonella spp. from both fish. Yersinia and Campylobacter species were effectively eliminated by doses of 1.5 and 3.0 kGy. Doses of 6.0 and 10.0 kGy caused a reduction in psychrotrophic counts but were detrimental to the quality of both species of fish

  14. DNA replication and repair of Tilapia cells: Pt. 2. Effects of temperature on DNA replication and ultraviolet repair in Tilapia ovary cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.D.; Yew, F.H.

    1988-02-01

    TO-2 is a fish cell line derived from the Tilapia ovary. It grows over a wide range of temperature (15-34/sup 0/C). We report the effects of temperature on DNA replication and u.v. repair in TO-2 cells. When the cells were moved from 31/sup 0/C to the sublethal high temperature of 37/sup 0/C, the rate of DNA synthesis first decreased to 60%, then speedy recovery soon set in, and after 8h at 37/sup 0/C the rate of DNA synthesis overshot the 31/sup 0/C control level by 180%. When moved to low temperature (18/sup 0/C) Tilapia cells also showed an initial suppression of DNA synthesis before settling at 30% of the control level. U.V. reduced but could not block DNA synthesis completely. The inhibition was overcome in 3h at 37, 31 and 25/sup 0/C, but not at 18/sup 0/C. Initiation of nascent DNA synthesis was blocked at 4Jm/sup -2/ in TO-2 cells compared with less than or equal to 1Jm/sup -2/ in mammalian cells. After 9Jm/sup -2/ u.v. irradiation, low molecular weight DNA replication intermediates started to accumulate. TO-2 cells showed low levels of u.v.-induced excision repair.

  15. Brain Transcriptome Profiling Analysis of Nile Tilapia (Oreochromis niloticus Under Long-Term Hypersaline Stress

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2018-03-01

    Full Text Available The fish brain plays an important role in controlling growth, development, reproduction, and adaptation to environmental change. However, few studies stem from the perspective of whole transcriptome change in a fish brain and its response to long-term hypersaline stress. This study compares the differential transcriptomic responses of juvenile Nile tilapia (Oreochromis niloticus maintained for 8 weeks in brackish water (16 practical salinity units, psu and in freshwater. Fish brains from each treatment were collected for RNA-seq analysis to identify potential genes and pathways responding to hypersaline stress. A total of 27,089 genes were annotated, and 391 genes were expressed differently in the salinity treatment. Ten pathways containing 40 differentially expressed genes were identified in the tilapia brain. Antigen processing and presentation and phagosome were the two principally affected pathways in the immune system. Thirty-one of 40 genes were involved in various expressions associated with environmental information processing pathways such as neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, the Jak-STAT signaling pathway, cell adhesion molecules (CAMs, and the PI3K-Akt signaling pathway, which are the upstream pathways for modulation of immunity and osmoregulation. The most-changed genes (>5-fold were all down-regulated, including four growth hormone/prolactin gene families, i.e., prolactin precursor (−10.62, prolactin-1 (−11, somatotropin (−10.15, somatolactin-like (−6.18, and two other genes [thyrotropin subunit beta (−7.73 and gonadotropin subunit beta-2 (−5.06] that stimulated prolactin release in tilapia. The downregulation pattern of these genes corroborates the decrease in tilapia immunity with increasing salinity and reveals an adaptive mechanism of tilapia to long-term hypersaline stress. Ovarian steroidogenesis, isoquinoline alkaloid biosynthesis, and phenylalanine metabolism are the

  16. Prevalence and diversity of fish-borne zoonotic trematodes in tilapia (Oreochromis niloticus) culture in Guangdong, China

    DEFF Research Database (Denmark)

    Li, Kang; Murrell, Kenneth Darwin; Clausen, Jesper Hedegaard

    The fishborne zoonotic trematode parasites (FZT) which cause liver and intestinal infections in humans are widespread in fish in Southeast Asia. Guangdong Province is the most important region for tilapia (Oreochromis niloticus) culture in China, but it is also an endemic region for FZT. To assess...... the potential for FZT transmission in an area with high density of tilapia farms, wild-caught fish from local rivers and canals were bought at local markets. The wild-caught fish species included Hemiculter leucisculus (145), Rhodeus sinensis Gunther (10), Rasborinus lineatus (96), Squaliobarbus curriculus (6......), and Carassius auratus (4).The FZT species recovered were mainly Haplorchis taichui, and H. pumilio along with some unknown species whose identifications are still being determined. Subsequently a cross-sectional survey for the prevalence and diversity of FZT in tilapia culture systems was conducted in Guangdong...

  17. Systems-level modeling the effects of arsenic exposure with sequential pulsed and fluctuating patterns for tilapia and freshwater clam

    International Nuclear Information System (INIS)

    Chen, W.-Y.; Tsai, J.-W.; Ju, Y.-R.; Liao, C.-M.

    2010-01-01

    The purpose of this paper was to use quantitative systems-level approach employing biotic ligand model based threshold damage model to examine physiological responses of tilapia and freshwater clam to sequential pulsed and fluctuating arsenic concentrations. We tested present model and triggering mechanisms by carrying out a series of modeling experiments where we used periodic pulses and sine-wave as featured exposures. Our results indicate that changes in the dominant frequencies and pulse timing can shift the safe rate distributions for tilapia, but not for that of freshwater clam. We found that tilapia increase bioenergetic costs to maintain the acclimation during pulsed and sine-wave exposures. Our ability to predict the consequences of physiological variation under time-varying exposure patterns has also implications for optimizing species growing, cultivation strategies, and risk assessment in realistic situations. - Systems-level modeling the pulsed and fluctuating arsenic exposures.

  18. Systems-level modeling the effects of arsenic exposure with sequential pulsed and fluctuating patterns for tilapia and freshwater clam

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.-Y. [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Tsai, J.-W. [Institute of Ecology and Evolutionary Ecology, China Medical University, Taichung 40402, Taiwan (China); Ju, Y.-R. [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Liao, C.-M., E-mail: cmliao@ntu.edu.t [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2010-05-15

    The purpose of this paper was to use quantitative systems-level approach employing biotic ligand model based threshold damage model to examine physiological responses of tilapia and freshwater clam to sequential pulsed and fluctuating arsenic concentrations. We tested present model and triggering mechanisms by carrying out a series of modeling experiments where we used periodic pulses and sine-wave as featured exposures. Our results indicate that changes in the dominant frequencies and pulse timing can shift the safe rate distributions for tilapia, but not for that of freshwater clam. We found that tilapia increase bioenergetic costs to maintain the acclimation during pulsed and sine-wave exposures. Our ability to predict the consequences of physiological variation under time-varying exposure patterns has also implications for optimizing species growing, cultivation strategies, and risk assessment in realistic situations. - Systems-level modeling the pulsed and fluctuating arsenic exposures.

  19. Growth hormone transgenic tilapia (Oreochromis sp.) compensate for increased metabolic rate to preserve exercise performance and hypoxia tolerance

    DEFF Research Database (Denmark)

    McKenzie, D.J.; Martínez, R.; Morales, A.

    2001-01-01

    Transgenic tilapia hybrids (Oreochromis mossambicus × O. hornorum) carrying a single copy of a homologous cDNA growth hormone exhibit higher growth rates than their wild-type conspecifics (Martinez et al. 1999). Swimming respirometry was employed to determine whether the increased growth rate...... higher in transgenics, such that aerobic scope was similar in both groups, and there was no difference in maximum sustainable U (5.2 ± 0.5 vs. 4.5 ± 0.7 bl s-1 in transgenics vs. wild-types, respectively). Following 2 h recovery from exercise, tilapia were exposed to progressive hypoxia (stepwise......Pa, respectively). The results indicate that stimulation of growth consequent to ectopic expression of growth hormone in transgenic tilapia (Martinez et al. 1999) is linked to increased rates of maintenance metabolism. The swimming and hypoxia experiments indicate, however, that the transgenics were able...

  20. Detection of Clostridium botulinum type C cells in the gastrointestinal tracts of Mozambique tilapia (Oreochromis mossambicus) by polymerase chain reaction

    Science.gov (United States)

    Nol, P.; Williamson, J.L.; Rocke, T.E.; Yuill, Thomas M.

    2004-01-01

    We established a method of directly detecting Clostridium botulinum type C cells, while minimizing spore detection, in the intestinal contents of Mozambique tilapia (Oreochromis mossambicus). This technique involved extraction of predominantly cellular DNA from tilapia intestinal tracts and used a polymerase chain reaction assay to detect presence of type C1 toxin gene. We consistently detected C. botulinum type C cells in tilapia gastrointestinal contents at a level of 7.5×104 cells per 0.25 g material or 1.9×103 cells. This technique is useful for determining prevalence of the potentially active organisms within a given population of fish and may be adapted to other types of C. botulinum and vertebrate populations as well.

  1. Differences in sexual size dimorphism among farmed tilapia species and strains undergoing genetic improvement for body weight

    Directory of Open Access Journals (Sweden)

    C.E. Lind

    2015-05-01

    Full Text Available Many tilapia (Oreochromis spp. farmers produce all-male populations because of the superior growth rate of males compared to females. To investigate differences in body weight at harvest of males and females among different tilapia strains, we analyzed data from 62,787 individuals collected from pedigreed breeding programs of O. niloticus (GIFT from Malaysia, the Abbassa line from Egypt, and the Akosombo line from Ghana, O. shiranus (the Bunda College-Domasi selection line, O. aureus (a selection line under development in Abbassa, Egypt, and a selection line from Israel and a synthetic selection line of Red tilapia under development in Jitra, Malaysia, derived from stock from Malaysia, Taiwan and Thailand (O. sp.. Mixed models were separately fitted to the data from each selection line. There was a significant sex effect in all strains (P < 0.001. A significant (P < 0.001 sex by generation interaction was observed in all strains (scale effect, not reversal of rankings, except Red tilapia and O. shiranus. Least squares means showed a large range in the magnitude of body weight differences between sexes across the seven strains. The largest percentage difference between females and males was in O. aureus from Egypt (female body weight was 52.2% that of males at harvest, whereas the smallest difference was observed in the GIFT strain of O. niloticus (female body weight 84.7% that of males. Female to male body weight percentages for Red tilapia, O. shiranus, Egypt O. niloticus, Israeli O. aureus and Ghana O. niloticus were 81.3, 81.0, 69.1, 61.7 and 61.0, respectively. We discuss the results in relation to the potential productivity improvements due to superior growth rates of all-male culture compared to mixed-sex culture in tilapia populations differing in the female to male body weight ratio.

  2. Successful xenogeneic germ cell transplantation from Jundia catfish (Rhamdia quelen) into adult Nile tilapia (Oreochromis niloticus) testes.

    Science.gov (United States)

    Silva, M A; Costa, G M J; Lacerda, S M S N; Brandão-Dias, P F P; Kalapothakis, E; Silva Júnior, A F; Alvarenga, E R; França, L R

    2016-05-01

    Fish germ cell transplantation presents several important potential applications for aquaculture, including the preservation of germplasm from endangered fish species with high genetic and commercial values. Using this technique in studies developed in our laboratory with adult male Nile tilapias (Oreochromis niloticus), all the necessary procedures were successfully established, allowing the production of functional sperm and healthy progeny approximately 2months after allogeneic transplantation. In the present study, we evaluated the viability of the adult Nile tilapia testis to generate sperm after xenogeneic transplant of germ cells from sexually mature Jundia catfish (Rhamdia quelen) that belong to a different taxonomic order. Therefore, in order to investigate at different time-periods post-transplantation, the presence and development of donor PKH26 labeled catfish germ cells were followed in the tilapia seminiferous tubules. From 7 to 20days post-transplantation, only PKH26 labeled spermatogonia were observed, whereas spermatocytes at different stages of development were found at 70days. Germ cell transplantation success and progression of spermatogenesis were indicated by the presence of labeled PKH26 spermatids and sperm on days 90 and 120 post-transplantation, respectively. Confirming the presence of the catfish genetic material in the tilapia testis, all recipient tilapias evaluated (n=8) showed the genetic markers evaluated. Therefore, we demonstrated for the first time that the adult Nile tilapia testis offers the functional conditions for development of spermatogenesis with sperm production from a fish species belonging to a different order, which provides an important new venue for aquaculture advancement. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Fatty acid concentration and proximate composition of acid silage from Nile tilapia (Oreochromis niloticus) waste, farmed in Indaiatuba – SP

    OpenAIRE

    Sales, Ronaldo de Oliveira; Universidade Federal do Ceará; Park, Kil Jin; Universidade Estadual de Campinas; de Morais, Selene Maia; Universidade Estadual de Ceará

    2013-01-01

    This study was conducted to determine the composition and fatty acid profile of the Nile tilapia waste silage with the aim of investigating its nutritional potential. Four lots (5 kg each) of Nile tilapia waste was ground with 3% (w/w) formic acid, stored at 27°C room temperature for 90 days in polyethylene boxes with holes, through which gases went out and then the levels of moisture, protein, ash and total lipids were analyzed obtaining: 77.25, 16.31, 3.17 and 3.26% respectively. 22 types o...

  4. Vaccination in Nile tilapia broodstock with whole cell vaccine and disease resistance in its fry against Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Sukenda Sukenda

    2017-07-01

    Full Text Available ABSTRACT The aim of this study was to analyze the effectivity of vaccination in Nile tilapia broodstock with whole cell vaccine and disease resistance in fry tilapia against Aeromonas hydrophila. Tilapia Nirwana strain that used for this had average body weight of 185±13.23 g and were maintained in ponds sizing of (2.5×2.5×1 m3. Vaccinations that has been done through intraperitoneal injection using dose of 0.1 mL/fish, meanwhile the fish for control was injected by phosphate buffered saline (PBS. This study used complete randomized design with two treatments and three replications. Antibody level was measured by using indirect enzyme-linked immunosorbent assay (ELISA method in the broodstock, egg, and fry.  Challenge test in fry tilapia performed at the age of 5, 10, and 15 days. The results showed that vaccination in tilapia broodstock delivered a significant antibody level in broodstock, eggs, and fry (P<0.05 compared to the control. Relative percent survival of offspring at 5, 10, and 15 days were 78.26%, 70.59%, and 65.52%, respectively.  As a conclusion, vaccination in tilapia broodstock was effective to improve specific and non-specific immunity, and protect fry tilapia from A. hydrophila infection through maternal immunity. Keywords: vaccination, antibody, maternal immunity, tilapia, Aeromonas hydrophila  ABSTRAK Penelitian ini bertujuan untuk menganalisis efikasi vaksinasi pada induk nila dengan vaksin sel utuh dan ketahanan benih yang dihasilkan terhadap Aeromonas hydrophila. Ikan nila stain Nirwana yang digunakan dalam penelitian memiliki bobot rata-rata 185±13,23 g dan ikan dipelihara dalam kolam (2,5×2,5×1 m3. vaksinasi dilakukan melalui penyuntikan intraperitoneal dengan dosis 0,1 mL/ikan, sementara itu ikan kontrol disuntik dengan phosphate buffered saline (PBS. Penelitian ini menggunakan rancangan acak lengkap dengan dua perlakuan dan tiga ulangan. Tingkat antibodi diukur dengan menggunakan metode indirect enzyme

  5. Sperm quality analysis in XX, XY and YY males of the Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Gennotte, V; François, E; Rougeot, C; Ponthier, J; Deleuze, S; Mélard, C

    2012-07-01

    In Nile tilapia (Oreochromis niloticus), individuals with atypical sexual genotype are commonly used in farming (use of YY males to produce all-male offspring), but they also constitute major tools to study sex determinism mechanisms. In other species, sexual genotype and sex reversal procedures affect different aspects of biology, such as growth, behavior and reproductive success. The aim of this study was to assess the influence of sexual genotype on sperm quality in Nile tilapia. Milt characteristics were compared in XX (sex-reversed), XY and YY males in terms of gonadosomatic index, sperm count, sperm motility and duration of sperm motility. Sperm motility was measured by computer-assisted sperm analysis (CASA) quantifying several parameters: total motility, progressive motility, curvilinear velocity, straight line velocity, average path velocity and linearity. None of the sperm traits measured significantly differed between the three genotypes. Mean values of gonadosomatic index, sperm concentration and sperm motility duration of XX, XY and YY males, respectively ranged from 0.92 to 1.33%, from 1.69 to 2.22 ×10(9) cells mL(-1) and from 18'04″ to 27'32″. Mean values of total motility and curvilinear velocity 1 min after sperm activation, respectively ranged from 53 to 58% and from 71 to 76 μm s(-1) for the three genotypes. After 3 min of activity, all the sperm motility and velocity parameters dropped by half and continued to slowly decrease thereafter. Seven min after activation, only 9 to 13% of spermatozoa were still progressive. Our results prove that neither sexual genotype nor hormonal sex reversal treatments affect sperm quality in male Nile tilapias with atypical sexual genotype. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Masculinization of red tilapia Oreochromis SPP. With steroid trenbolone acetate (TBA provided in the food

    Directory of Open Access Journals (Sweden)

    Apolinar Santamaría Miranda

    2012-09-01

    Full Text Available The tilapia culture in our country has presented in recent years a significant rise and diversification, this due to the food shortage in our country and in the rest of the world, there are some alternatives to increase the profitability of their crop and is also an activity important in the state of Sinaloa, mainly in the communities adjacent to the dams and reservoirs of water. Inthe present study we present the results obtained in the process of sex reversal of red tilapia fingerlings Oreochromis sp., held at the premises of CIIDIR-IPN, Guasave, Sinaloa. The experiment used a total population of 4000 organisms, which were distributed in three hormonal treatment ponds by integrating them into the food (ATB and three controls (C, were concrete ponds with a capacity of 500 L. water was applied to the food hormone to be administered orally. The percent change of sex was determined by the technique "Squash". In the treatment hormonado food supply. The physicochemical parameters were not significantly different because they are within the limits allowed in growing tilapia. Survival in the treatment of hormonedelivery was the result was 89.6 ± 2.5% and 78.0 ± 3.2% control. In her final weight (g application in the treatment of hormone was 0.52 ± 0.02 g and the control was 0.50 ± 0.04 g. The percentage reversal of the sexual hormone treatment (TBAwas 89.7 ± 3.0% in the control (C was 57.0 ± 2.3%. This allowed to know which is more effective use of the hormone in the food.

  7. Five different piscidins from Nile tilapia, Oreochromis niloticus: analysis of their expressions and biological functions.

    Directory of Open Access Journals (Sweden)

    Kuan-Chieh Peng

    Full Text Available Piscidins are antimicrobial peptides (AMPs that play important roles in helping fish resist pathogenic infections. Through comparisons of tilapia EST clones, the coding sequences of five piscidin-like AMPs (named TP1∼5 of Nile tilapia, Oreochromis niloticus, were determined. The complete piscidin coding sequences of TP1, -2, -3, -4, and -5 were respectively composed of 207, 234, 231, 270, and 195 bases, and each contained a translated region of 68, 77, 76, 89, and 64 amino acids. The tissue-specific, Vibrio vulnificus stimulation-specific, and Streptococcus agalactiae stimulation-specific expressions of TP2, -3, and -4 mRNA were determined by a comparative RT-PCR. Results of the tissue distribution analysis revealed high expression levels of TP2 mRNA in the skin, head kidneys, liver, and spleen. To study bacterial stimulation, S. agalactiae (SA47 was injected, and the TP4 transcript was upregulated by >13-fold (compared to the wild-type (WT control, without injection and was 60-fold upregulated (compared to the WT control, without injection 24 h after the S. agalactiae (SA47 injection in the spleen and gills. Synthesized TP3 and TP4 peptides showed antimicrobial activities against several bacteria in this study, while the synthesized TP1, -2, and -5 peptides did not. The synthesized TP2, -3, and -4 peptides showed hemolytic activities and synthesized TP3 and TP4 peptides inhibited tilapia ovary cell proliferation with a dose-dependent effect. In summary, the amphiphilic α-helical cationic peptides of TP3 and TP4 may represent novel and potential antimicrobial agents for further peptide drug development.

  8. Effects of dietary genistein on GH/IGF-I axis of Nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Chen, Dong; Wang, Wei; Ru, Shaoguo

    2016-09-01

    There is considerable concern that isoflavones, such as genistein in fish feed composed of soybean protein, aff ects somatic growth in fish. Our previous works demonstrated that 30 and 300 μg/g dietary genistein had no significant eff ect on growth performance in Nile tilapia ( Oreochromis niloticus), but the higher level of genistein (3 000 μg/g) significantly depressed growth. This study was conducted to further examine the eff ects of dietary genistein on the endocrine disruption on growth hormone/insulin-like growth factor-I (GH/IGF-I) axis in Nile tilapia ( O. niloticus). Juvenile fish were fed by hand twice daily to satiation with one of four isonitrogenous and isoenergetic diets, each containing either 0, 30, 300 or 3 000 μg/g genistein. Following an 8-week feeding period, plasma GH and IGF-I levels were investigated by radioimmunoassay and gene expression levels of gh, ghrelin, gnrhs, ghr, npy, npyrs, pacap, ghrs, i gf-I, igf-Ir, and igfbp3 were examined by real-time PCR. The results show that no significant change in plasma GH and IGF-I levels in fish fed with diets containing 30 μg/g and 300 μg/g genistein. mRNA expression of genes along the GH/IGF-I axis remained unaff ected, except for igf-Ir, which was stimulated by the 300 μg/g genistein diet. While in fish fed the 3 000 μg/g genistein diet, the plasma GH and IGF-I levels decreased, and mRNA expression of gh, ghr2, npyr1, igf-I, and igf-Ir were also significantly depressed. In contrast, npy and igfbp3 mRNA expression were enhanced. This study provides convincing evidence for growth impediment by genistein by disturbing the GH/IGF-I axis in Nile tilapia O. niloticus.

  9. Characterization and localization of metal-responsive-element-binding transcription factors from tilapia

    International Nuclear Information System (INIS)

    Cheung, Andrew Pok-Lap; Au, Candy Yee-Man; Chan, William Wai-Lun; Chan, King Ming

    2010-01-01

    Two isoforms of MTF-1, MTF-1L (long form) and MTF-1S (short form), were cloned in tilapia (Ti) and characterized in a tilapia liver cell line, Hepa-T1. The cloned tiMTF-1L has the characteristics of all of the tiMTF-1S identified so far with the zinc finger domain having six fingers, the acidic-rich, proline-rich, and serine/threonine-rich domains; however, the short form encodes for the zinc finger domain with five zinc fingers only and no other domains. The transient transfection of tiMTF-1L into human HepG2 cells showed both constitutive and zinc-induced metal-responsive-element (MRE)-driven reporter gene expression. However, the transfection of tiMTF-1S (which lacks all three transactivation domains) into a human cell line showed reduced transcriptional activities compared with an endogenous control in both basal- and Zn 2+ -induced conditions. The tiMTF-1 isoforms were tagged with GFP and transfected into Hepa-T1 cells (tilapia hepatocytes). The nuclear translocation of tiMTF-1L was observed when the cells were exposed to a sufficient concentration of metals for 6 h. However, tiMTF-1S, was localized in the nucleus with or without metal treatment. Electrophoretic mobility shift assay (EMSA) confirmed that both of the isoforms were able to bind to the MRE specifically in vitro. Tissue distribution studies showed that tiMTF-1L was more abundant than tiMTF-1S in all of the tissues tested.

  10. Electrospun tilapia collagen nanofibers accelerating wound healing via inducing keratinocytes proliferation and differentiation.

    Science.gov (United States)

    Zhou, Tian; Wang, Nanping; Xue, Yang; Ding, Tingting; Liu, Xin; Mo, Xiumei; Sun, Jiao

    2016-07-01

    The development of biomaterials with the ability to induce skin wound healing is a great challenge in biomedicine. In this study, tilapia skin collagen sponge and electrospun nanofibers were developed for wound dressing. The collagen sponge was composed of at least two α-peptides. It did not change the number of spleen-derived lymphocytes in BALB/c mice, the ratio of CD4(+)/CD8(+) lymphocytes, and the level of IgG or IgM in Sprague-Dawley rats. The tensile strength and contact angle of collagen nanofibers were 6.72±0.44MPa and 26.71±4.88°, respectively. They also had good thermal stability and swelling property. Furthermore, the nanofibers could significantly promote the proliferation of human keratinocytes (HaCaTs) and stimulate epidermal differentiation through the up-regulated gene expression of involucrin, filaggrin, and type I transglutaminase in HaCaTs. The collagen nanofibers could also facilitate rat skin regeneration. In the present study, electrospun biomimetic tilapia skin collagen nanofibers were succesfully prepared, were proved to have good bioactivity and could accelerate rat wound healing rapidly and effectively. These biological effects might be attributed to the biomimic extracellular matrix structure and the multiple amino acids of the collagen nanofibers. Therefore, the cost-efficient tilapia collagen nanofibers could be used as novel wound dressing, meanwhile effectively avoiding the risk of transmitting animal disease in the future clinical apllication. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Salinity-induced regulation of the myo-inositol biosynthesis pathway in tilapia gill epithelium

    Science.gov (United States)

    Sacchi, Romina; Li, Johnathon; Villarreal, Fernando; Gardell, Alison M.; Kültz, Dietmar

    2013-01-01

    SUMMARY The myo-inositol biosynthesis (MIB) pathway converts glucose-6-phosphate to the compatible osmolyte myo-inositol that protects cells from osmotic stress. Using proteomics, the enzymes that constitute the MIB pathway, myo-inositol phosphate synthase (MIPS) and inositol monophosphatase 1 (IMPA1), are identified in tilapia (Oreochromis mossambicus) gill epithelium. Targeted, quantitative, label-free proteomics reveals that they are both upregulated during salinity stress. Upregulation is stronger when fish are exposed to severe (34 ppt acute and 90 ppt gradual) relative to moderate (70 ppt gradual) salinity stress. IMPA1 always responds more strongly than MIPS, suggesting that MIPS is more stable during salinity stress. MIPS is N-terminally acetylated and the corresponding peptide increases proportionally to MIPS protein, while non-acetylated N-terminal peptide is not detectable, indicating that MIPS acetylation is constitutive and may serve to stabilize the protein. Hyperosmotic induction of MIPS and IMPA1 is confirmed using western blot and real-time qPCR and is much higher at the mRNA than at the protein level. Two distinct MIPS mRNA variants are expressed in the gill, but one is more strongly regulated by salinity than the other. A single MIPS gene is encoded in the tilapia genome whereas the zebrafish genome lacks MIPS entirely. The genome of euryhaline tilapia contains four IMPA genes, two of which are expressed, but only one is salinity regulated in gill epithelium. The genome of stenohaline zebrafish contains a single IMPA gene. We conclude that the MIB pathway represents a major salinity stress coping mechanism that is regulated at multiple levels in euryhaline fish but absent in stenohaline zebrafish. PMID:24072791

  12. Characterization and localization of metal-responsive-element-binding transcription factors from tilapia

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Andrew Pok-Lap; Au, Candy Yee-Man; Chan, William Wai-Lun [Department of Biochemistry, Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong (Hong Kong); Chan, King Ming, E-mail: kingchan@cuhk.edu.hk [Department of Biochemistry, Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong (Hong Kong)

    2010-08-01

    Two isoforms of MTF-1, MTF-1L (long form) and MTF-1S (short form), were cloned in tilapia (Ti) and characterized in a tilapia liver cell line, Hepa-T1. The cloned tiMTF-1L has the characteristics of all of the tiMTF-1S identified so far with the zinc finger domain having six fingers, the acidic-rich, proline-rich, and serine/threonine-rich domains; however, the short form encodes for the zinc finger domain with five zinc fingers only and no other domains. The transient transfection of tiMTF-1L into human HepG2 cells showed both constitutive and zinc-induced metal-responsive-element (MRE)-driven reporter gene expression. However, the transfection of tiMTF-1S (which lacks all three transactivation domains) into a human cell line showed reduced transcriptional activities compared with an endogenous control in both basal- and Zn{sup 2+}-induced conditions. The tiMTF-1 isoforms were tagged with GFP and transfected into Hepa-T1 cells (tilapia hepatocytes). The nuclear translocation of tiMTF-1L was observed when the cells were exposed to a sufficient concentration of metals for 6 h. However, tiMTF-1S, was localized in the nucleus with or without metal treatment. Electrophoretic mobility shift assay (EMSA) confirmed that both of the isoforms were able to bind to the MRE specifically in vitro. Tissue distribution studies showed that tiMTF-1L was more abundant than tiMTF-1S in all of the tissues tested.

  13. Partition and metabolic fate of dietary glycerol in muscles and liver of juvenile tilapia.

    Science.gov (United States)

    da Costa, Diego Vicente; Dias, Jorge; Colen, Rita; Rosa, Priscila Vieira; Engrola, Sofia

    2017-04-01

    This study investigated the effect of dietary glycerol on the metabolism of juvenile tilapia (Oreochromis mossambicus) and to determine its metabolic fate. The experimental diets contained 0% (Group CON), 5% (Group G5) and 15% glycerol (Group G15) and were fed for 40 d to apparent satiation, three times a day. For the metabolism trials, six fish from each treatment were randomly chosen and tube-fed with five pellets labelled with 14 C-glycerol [ 14 C(U)] in order to evaluate the absorption, catabolism, retention and partition of glycerol in muscle and liver. Group G5 presented the highest 14 C-glycerol retention and the lowest catabolism, with no significant differences between Groups CON and G15. In Group CON, the highest percentage of 14 C was incorporated in muscle lipids; with no significant differences between Groups G5 and G15. Furthermore, no treatment effects were found for hepatic 14 C-lipid and for 14 C in hepatic and muscle non-lipid extract. In the non-lipid and non-protein fraction, the highest radioactivity was measured in livers of Group G5, however no significant differences were found for this fraction between Groups CON and G15 in liver and for all treatments in muscle. The results of the present study can have practical implications in diet formulations for tilapia and for other aquaculture species with similar feeding pattern since juvenile tilapia are able to metabolise dietary glycerol into lipids, protein and/or carbohydrates and to use it as energy source.

  14. Development of a colloidal gold immunochromatographic strip for rapid detection of Streptococcus agalactiae in tilapia.

    Science.gov (United States)

    Wen-de, Wu; Min, Li; Ming, Chen; Li-Ping, Li; Rui, Wang; Hai-Lan, Chen; Fu-Yan, Chen; Qiang, Mi; Wan-Wen, Liang; Han-Zhong, Chen

    2017-05-15

    A colloidal gold immunochromatographic strip was developed for rapid detection of Streptococcus agalactiae (S. agalactiae) infection in tilapia. The monoclonal antibodies (mAb) 4C12 and 3A9 were used to target S. agalactiae as colloidal gold-mAb conjugate and captured antibody, respectively. The colloidal gold immunochromatographic strip was assembled via routine procedures. Optimal pH and minimum antibody levels in the reaction system for gold colloidal-mAb 4C12 conjugation were pH 7.4 and 18μg/mL, respectively. Optimal concentrations of the captured antibody 3A9 and goat anti-mouse antibody were 0.6mg/mL and 2mg/mL, respectively. The sensitivity of the strip for detecting S. agalactiae was 1.5×10 5 colony forming units (CFU). No cross-reaction was observed with other commonly encountered bacteria, including Pseudomonas fluorescens, Aeromonas hydrophila, Vibrio anguillarum and Streptococcus iniae. The assay time for S. agalactiae was less than 15min. Tilapia samples artificially infected with S. agalactiae were tested using the newly developed strip. The results indicated that blood, brain, kidney, spleen, metanephros and intestine specimens of infected fish can be used for S. agalactiae detection. The validity of the strip was maintained for 6 months at 4°C. These findings suggested that the immunochromatographic strip was effective for spot and rapid detection of S. agalactiae infected tilapia. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Characteristic study of chitosan addition in Tilapia (Oreochromis niloticus) bone based gelatin film

    Science.gov (United States)

    Atmaka, W.; Yudhistira, B.; Putro, M. I. S.

    2018-03-01

    Tilapia (Oreochromis niloticus) is one of popular fish species in Indonesia. The high number in tilapia’s production and export of tilapia resulting in the increase of bone fish waste. an attempt to decrease the amount of the aforementioned waste, the fish bones were turned into gelatine. The gelatine produced from this waste can be put to good use by turning it into edible film due to its high water resistance and low tensile strength value. However, in order to make a proper film, both the water resistance and the tensile strength value needs another appropriate additional biopolymer. In this case, the appropriate biopolymer needed both to form the film and to repair its characteristics is chitosan. The purpose of this research is to find out the effect of the chitosan addition on the tilapia bone based gelatine film. The research used several mixtures of gelatine (G) and chitosan (C) with the following ratio: G100:C0 (GC1), G75:C25 (GC2), G50:C50 (GC3), G25:C75 (GC4), G0:C100 (GC5). ANOVA results (Psolubility, tensile strength, elongation at break, Fourier Transform Infrared (FTIR), color a, and color b but no significant effects on the vapor permeability and color L. The best result is shown on GC2 with thickness 0.119 mm; solubility 74.95%; tensile strength 2.635 Mpa; elongation at break 68.26%; water vapor permeability 5.897 g/h m2 and FTIR. The parameters in GC2 shows good compatibility between the two biopolymers.

  16. Dietary camu camu, Myrciaria dubia, enhances immunological response in Nile tilapia.

    Science.gov (United States)

    Yunis-Aguinaga, Jefferson; Fernandes, Dayanne C; Eto, Silas F; Claudiano, Gustavo S; Marcusso, Paulo F; Marinho-Neto, Fausto A; Fernandes, João B K; de Moraes, Flávio R; de Moraes, Julieta R Engrácia

    2016-11-01

    Camu camu, Myrciaria dubia, is an Amazon plant that presents high levels of vitamin C in its composition. Several studies in animals and humans have demonstrated their efficiency in the prevention and treatment of various diseases. However, there are no reports of its properties in fish. The aim of this study was to evaluate the effect of the oral administration of the extract of this plant in the immune parameters in Nile tilapia, Oreochromis niloticus. 400 Nile tilapia (80 ± 5 g) were randomly distributed into 20 tanks with 1500 L capacity each (20 fish/tank). After a week of adaptation to environmental conditions, it was provided a diet for 5 weeks, using different levels of inclusion of camu camu extract: 0, 50, 100, 250, and 500 mg/kg of feed. Each treatment consisted of four replicates. It was obtained 40.5 mg of vitamin C/g of camu camu pulp powder by high-performance liquid chromatography. At the end of the trial period, fish were inoculated with Aeromonas hydrophila in the swim bladder. Samples were taken after 6; 24 and 48 h of the challenge. Results revealed that fish supplemented with this herb showed significant increase (P  0.05). No histopathological lesions were observed in intestine, kidney, spleen, and gills. It can be concluded that the addition of Myrciaria dubia in tilapia feed improves the immune response and the growth after 5 weeks, especially, at a dose of 500 mg/kg. Copyright © 2016. Published by Elsevier Ltd.

  17. DNA replication and repair in Tilapia cells. 1. The effect of ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Yew, F.H.; Chang, L.M. (National Taiwan Univ., Taipei (China))

    1984-12-01

    The effect of ultraviolet radiation on a cell line established from the warm water fish Tilapia has been assessed by measuring the rate of DNA synthesis, excision repair, post-replication repair and cell survival. The cells tolerate ultraviolet radiation better than mammalian cells with respect to DNA synthesis, post-replication repair and cell survival. They are also efficient in excision repair, which in other fish cell lines has been found to be at a low level or absent. Their response to the inhibitors hydroxyurea and 1-..beta..-D-arabinofuranosylcytosine is less sensitive than that of other cell lines, yet the cells seem to have very small pools of DNA precursor.

  18. Fermentation of Azolla sp. leaves and the utilization as a feed ingredient of tilapia Oreochromis sp.

    Directory of Open Access Journals (Sweden)

    Nur Bambang Priyo Utomo

    2015-03-01

    Full Text Available ABSTRACTThe objective of this study was to study the effect of incubation period on the nutritional content of Azolla sp. meal fermented by Trichoderma harzianum, and its optimum supplementation level in the feed of tilapia Oreochromis sp. In incubation period treatments, fermentation of Azolla meal was performed in two, six, eight, and ten days (AF2, AF6, AF8, AF10 using Trichoderma harzianum as the fermentor. The fish used in this study was tilapia Oreochromis sp. with an average weight of 10.59±1.29 g. The design of the feeding treatments was repeletting commercial feed with Azolla leaves by with different supplementation levels, i.e. 0% (A/control, 30% (B, 60% (C, and 90% (D. Faecal collection for digestibility measurement was conducted for 15 days and fish growth rate was observed for 40 days. Azolla meal fermented for two days (AF2 showed the best results among the other treatments with a crude fiber decrease of 37.19% and protein increase of 38.65%. The results of this study indicate that fermentation can increase the nutritional quality of Azolla meal and its most optimal supplementation level in the diet of tilapia is 30%.Keywords: crude fiber, Azolla sp., tilapiaABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh lama waktu fermentasi daun mata lele Azolla sp. menggunakan kapang Trichoderma harzianum serta dosis optimal dalam pakan ikan nila Oreochromis sp. Proses fermentasi tepung daun mata lele dilakukan selama dua, enam, delapan, dan sepuluh hari (AF2, AF6, AF8, AF10. Ikan uji pada penelitian ini menggunakan ikan nila Oreochromis sp. dengan bobot rata-rata 10,59±1,29 g yang ditebar sebanyak 6 ekor/akuarium berukuran 50×45×30 cm3. Sebagai pakan perlakuan yakni repeletting daun mata lele dengan pakan komersil pada tingkat suplementasi 0% (A/kontrol, 30% (B, 60% (C, dan 90% (D. Pemeliharaan ikan uji dan pengumpulan data dilakukan dengan mengumpulkan feses ikan untuk uji ketercernaan selama 15 hari dan mengamati pertumbuhan

  19. EFFECTS OF THE HEAVY METAL, ZINC, ON THE FRESHWATER FISH TILAPIA NILOTICA L.

    Directory of Open Access Journals (Sweden)

    VIRGINIA S. CARING

    1992-01-01

    Full Text Available Gills, gonads, and blood of Tilapia nilotica exposed to different concentrations of zinc sulfate (ZnSO4. 7H2O exhibited histological effects. Gills of posthatch larvae exposed chronically for 21 days to 2 ppm zinc sulfate and fingerlings to 10 ppm sublethal zinc concentrations exhibited hyperplasia that resulted in fusion of adjacent secondary gill lamellae. The same effects were observed in 4-hour short-term exposure to 30 ppm lethal dose. Posthatch larvae subjected to 2 and 5 ppm sublethal levels of zinc for 30 days retained undifferentiated gonads with differentiation with oogonial proliferation. Ovaries of control fish demonstrated healthy oocyte growth and other normal histological features after 57 days. In contrast, ovaries in treated groups exhibited excessive amounts of connective tissue, hyperemia and markedly reduced oocyte number. Oocytes had wavy irregular surface outlines. Deviation from normal was observed to be dose dependent. In juvenile tilapia, spermatogenesis was observed in control testes. Testes of zinc-exposed fish, on the other hand, remained immature. Hyperemia was markedly pronounced in both testes and ovary after 90 days exposure to zinc. Blood of Tilapia nilotica fingerlings exposed to sublethal concentrations of 2, 5, and 10 ppm zinc for 30, 60, and 90 days exhibited anisocytosis and poikilocytosis. There was an increase in hematocrit values in zinc-reared fish which, however, reverted to control/near control levels at day 90. Hemoglobin values were inversely proportional to the level of zinc in the rearing water. The marked reduction in hemoglobin values in fish reared at the higher zinc concentrations of 5 and 10 ppm suggests the development of some degree of anemia which is also supported by the observations of anisocytosis and poikilocytosis. INTRODUCTION Heavy metal contamination of aquatic environments has become a current serious problem because of increased industrialization. In the Philippines, data gathered

  20. Evaluation of Radioactivity Concentration in Tilapia Nilotica and Radiation Dose to Egyptian Population

    Science.gov (United States)

    Amer, Hannan H.; El-Khawas, Enas H.

    2013-03-01

    One of the three goals of the United Nations for sustainable food security is to ensure that all people have access to sufficient, nutritionally adequate, and safe food. The study was carried out to evaluate the Uranium (238U) and thorium (232Th) concentration in the Bolti (Tilapia nilotica) fish collected from Nasser Lake by using two different types of detectors CR-39 SSNTDs and gamma spectroscopy. The annual intake of Bolti fish was estimated on the basis of their average annual consumption. Calculations were also made to determine the effective dose to an individual consuming such diet.

  1. Evaluation of Radioactivity Concentration In Tilapia Nilotica and Radiation Dose to Egyptian Population

    International Nuclear Information System (INIS)

    Amer, H.H.; Khawas, E.H.; Nabil, G.M.

    2011-01-01

    One of the three goals of the United Nations for sustainable food security is to ensure that all people have access to sufficient, nutritionally adequate and safe food. The study was carried out to evaluate the uranium ( 238 U) and thorium ( 232 Th) concentrations in the Bolti fish (Tilapia nilotica) collected from Naser Lake by using two different types of detectors CR-39 SSNTD and gamma spectroscopy. The annual intake of Bolti fish was estimated on the basis of their average annual consumption. Calculations were also made to determine the effective dose to an individual consuming such diet

  2. Occurrence of bacterial pollution indicators in Boulti (Tilapia nilotica Linn. ) fish

    Energy Technology Data Exchange (ETDEWEB)

    El-Zanfaly, H.T.; Ibrahim, A.A.

    1982-09-01

    A study was made for the occurrence of coliform and streptococcal groups on the skin surface (32 samples), gills (32 samples), intestinal tract (4 samples) and raw fish flesh (4 samples) and raw fish flesh (4 samples) of Boulti fish (Tilapia nilotica Linn.), a fresh water fish caught from Nasser's Lake in Aswan. Streptococcus group was detected in 13 samples taken from fish surface, 12 samples out of 32 swabs from gills. All intestine samples and raw fish flesh were positive for the streptococcus group. Coliform organisms were detected at nearly 43% of skin or gill samples, 100% of intestine and raw fish flesh samples.

  3. Riesgos de la introducción de tilapias (Oreochromis sp. (Perciformes: Cichlidae en ecosistemas acuáticos de Chile Risks of the introduction of tilapia (Oreochromis sp. (Perciformes: Cichlidae in aquatic ecosystems of Chile

    Directory of Open Access Journals (Sweden)

    2004-03-01

    Full Text Available Se hace un llamado de alerta ante la posible introducción de la tilapia roja (Oreochromis sp. a Chile, con fines de cultivo. Se analizan los llamados cultivos monosexuales (solo machos, señalados como la solución para impedir la reproducción no deseada, que evitaría riesgos para la biodiversidad y se demuestra la falsedad de este argumento. Énfasis especial se da a los cultivos de tilapia en áreas marinas. Los peligros para la biodiversidad, son resaltadosA call of attention is made over the possible introduction of red tilapia (Oreochromis sp. for aquaculture in Chile. The so-called monosex (all male culture, considered by some as the solution for unwanted reproduction and for avoiding risks for biodiversity, are analyzed, and the falsehood of this argument is demonstrated. Special emphasis is given to the tilapia culture in marine areas. Threats to biodiversity are stressed

  4. Impact of microcystin containing diets on physiological performance of Nile tilapia (Oreochromis niloticus) concerning stress and growth

    Czech Academy of Sciences Publication Activity Database

    Ziková, A.; Trubiroha, A.; Wiegand, C.; Wuertz, S.; Rennert, B.; Pflugmacher, S.; Kopp, Radovan; Mareš, J.; Kloas, W.

    2010-01-01

    Roč. 29, č. 3 (2010), s. 561-568 ISSN 0730-7268 Institutional research plan: CEZ:AV0Z60050516 Keywords : microcystin * Nile tilapia * physiological performance Subject RIV: EF - Botanics Impact factor: 3.026, year: 2010

  5. Comparative population genetic structure of redbelly tilapia (Coptodon zillii (Gervais, 1848)) from three different aquatic habitats in Egypt

    KAUST Repository

    Soliman, Taha

    2017-11-16

    Recently, tilapia have become increasingly important in aquaculture and fisheries worldwide. They are one of the major protein sources in many African countries and are helping to combat malnutrition. Therefore, maintenance and conservation genetics of wild populations of tilapia are of great significance. In this study, we report the population genetic structure and genetic diversity of the redbelly tilapia (Coptodon zillii) in three different Egyptian aquatic environments: brackish (Lake Idku), marine (Al-Max Bay), and freshwater (Lake Nasser). The habitat differences, environmental factors, and harvesting pressures are the main characteristics of the sampling sites. Three mitochondrial DNA markers (COI: cytochrome oxidase subunit I; the D-loop; CYTB: cytochrome b) were used to assess population structure differences among the three populations. The population at Lake Nasser presented the highest genetic diversity (Hd = 0.8116, H = 6), and the marine population of Al-Max Bay the lowest (Hd = 0.2391, H = 4) of the combined sequences. In addition, the phylogenetic haplotype network showed private haplotypes in each environmental habitat. Results presented here will be useful in aquaculture to introduce the appropriate broodstock for future aquaculture strategies of C. zillii. In addition, evidence of population structure may contribute to the management of tilapia fisheries in Egyptian waters.

  6. Carob seed germ meal as a partial soybean meal replacement in the diets of red hybrid tilapia

    Directory of Open Access Journals (Sweden)

    Abdalbast H.I. Fadel

    2017-12-01

    Full Text Available The feasibility of carob seed germ meal (CSGM as a soybean meal (SBM replacement in the diet of red tilapia hybrid was evaluated in an 8-week feeding trial. Five isonitrogenous and isocaloric diets with increasing CSGM (0, 10, 20, 30 and 40%, at the expense of SBM, were fed to triplicated groups of tilapia fingerlings. Their growth, feeding efficiency, whole body proximate composition, selected plasma biochemical parameters, and liver and gut histopathology were assessed. The survival and growth of red tilapia were unaffected by the dietary CSGM inclusion up to 30%. Growth and feeding efficiencies were significantly reduced at 40% CSGM inclusion. Hematocrit and body crude lipid were significantly lower (p < 0.05 in fish fed 30–40% CSGM while plasma ALT and protein were significantly higher compared to the control (0% CSGM. In addition, some instances of lipofuscin and cellular degradation were shown in liver while morphological changes were observed in fish fed 30 and 40% CSGM. Some of these included a 60% and 34% reduction in goblet cell prevalence and villi length, respectively, as well as a thickening of the intestinal mucosal and submucosa layers of 51 and 27%, respectively as dietary CSGM increased from 0 to 40%, that was likely due to increased anti-nutritional factors. In conclusion, a dietary inclusion of only up to 20% untreated CSGM was recommended for red hybrid tilapia.

  7. Energy efficiency of digestible protein, fat and carbohydrate utilisation for growth in rainbow trout and Nile tilapia.

    Science.gov (United States)

    Schrama, Johan W; Haidar, Mahmoud N; Geurden, Inge; Heinsbroek, Leon T N; Kaushik, Sachi J

    2018-04-01

    Currently, energy evaluation of fish feeds is performed on a digestible energy basis. In contrast to net energy (NE) evaluation systems, digestible energy evaluation systems do not differentiate between the different types of digested nutrients regarding their potential for growth. The aim was to develop an NE evaluation for fish by estimating the energy efficiency of digestible nutrients (protein, fat and carbohydrates) and to assess whether these efficiencies differed between Nile tilapia and rainbow trout. Two data sets were constructed. The tilapia and rainbow data set contained, respectively, eight and nine experiments in which the digestibility of protein, fat and energy and the complete energy balances for twenty-three and forty-five diets was measured. The digestible protein (dCP), digestible fat (dFat) and digestible carbohydrate intakes (dCarb) were calculated. By multiple regression analysis, retained energy (RE) was related to dCP, dFat and dCarb. In tilapia, all digestible nutrients were linearly related to RE (Pefficiency of dCP, dFat and dCarb was 49, 91 and 66 %, respectively, showing large similarity with pigs. Tilapia and trout had similar energy efficiencies of dCP (49 v. 57 %) and dFat (91 v. 84 %), but differed regarding dCarb.

  8. Effect of constant digestible protein intake and varying digestible energy levels on energy and protein utilization in Nile tilapia

    NARCIS (Netherlands)

    Haidar, M.N.; Bleeker, S.; Heinsbroek, L.T.N.; Schrama, J.W.

    2018-01-01

    In literature, the variability in the estimated optimal digestible protein to digestible energy ratio (DP/DE) is high. The present study aimed to estimate the optimal DP/DE ratio in Nile tilapia (Oreochromis niloticus) using different criteria (performance, energy and nitrogen balances parameters).

  9. Fishborne trematodes in cultured Nile tilapia (Oreochromis niloticus) and wild-caught fish from Thailand

    DEFF Research Database (Denmark)

    Wiriya, Benjamaporn; Clausen, Jesper Hedegaard; Inpankaew, Tawin

    2013-01-01

    Fish-borne zoonotic trematode (FZT) infections affect the health of more than 18 million people around the world, particularly in Asian countries. Nile tilapia (Oreochromis niloticus) is a white meat fish that has an increasing national and international market. The objective of this study was to...... for vigilance and good management practices by the aquaculture sector. Crown...

  10. A comparative study of the metabolic response in rainbow trout and Nile tilapia to changes in dietary macronutrient composition.

    Science.gov (United States)

    Figueiredo-Silva, A Cláudia; Saravanan, Subramanian; Schrama, Johan W; Panserat, Stéphane; Kaushik, Sadasivam; Geurden, Inge

    2013-03-14

    Metabolic mechanisms underlying the divergent response of rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus) to changes in dietary macronutrient composition were assessed. Fish were fed one of four isoenergetic diets having a digestible protein-to-digestible energy (DP:DE) ratio above or below the optimal DP:DE ratio for both species. At each DP:DE ratio, fat was substituted by an isoenergetic amount of digestible starch as the non-protein energy source (NPE). Dietary DP:DE ratio did not affect growth and only slightly lowered protein gains in tilapia. In rainbow trout fed diets with low DP:DE ratios, particularly with starch as the major NPE source, growth and protein utilisation were highly reduced, underlining the importance of NPE source in this species. We also observed species-specific responses of enzymes involved in amino acid catabolism, lipogenesis and gluconeogenesis to dietary factors. Amino acid transdeamination enzyme activities were reduced by a low dietary DP:DE ratio in both species and in tilapia also by the substitution of fat by starch as the NPE source. Such decreased amino acid catabolism at high starch intakes, however, did not lead to improved protein retention. Our data further suggest that a combination of increased lipogenic and decreased gluconeogenic enzyme activities accounts for the better use of carbohydrates and to the improved glycaemia control in tilapia compared with rainbow tront fed starch-enriched diets with low DP:DE ratio.

  11. Time related alterations in digestibility and faecal characteristics as affected by dietary composition in the Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    Amirkolaie, A.K.; Schrama, J.W.

    2015-01-01

    After being shifted to a new diet, time related alterations in digestibility, faecal waste production and faeces recovery in Nile tilapia were assessed in relation with dietary ingredient composition. Four experimental diets were formulated according to a 2 by 2 factorial design: two starch

  12. Effects of replacing fishmeal with wastes derived from local fisheries on the growth of juvenile tilapia, Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Chanagun Chitmanat

    2009-01-01

    Full Text Available A feeding trial was conducted to investigate the effects of partially and totally replacing fishmeal with by-product derived from local fisheries on growth performances of tilapia (Oreochromis niloticus. Tilapia fingerlings (average initialweight 0.38±0.05 g were fed with 5 different diet formulas composing of fish meal protein replacement levels of 0%, 25%,50%, 75, and 100%. Tilapia were raised in 80 x 80 x 80 cm3 hapa in an earthen pond for 8 weeks. Each treatment contained3 replications. No feeding trial was applied as negative control. The result showed that fish by-product powder could substitute for fishmeal on a crude protein basis at a level of not more than 25%. As a result, feed cost can only be cut down approximately 3 US cents/kg. Specific growth rate, weight gain, survival rate and feed conversion ratio were not significantly different between the fish fed with the 75% and 100% fishmeal containing diets (P>0.05. The outcome would beapplied to reduce the solid wastes from fish processing and partially replace the imported fishmeal. This can also be used as guideline for farmers in small communities to produce their own tilapia feed.

  13. Notochord in Tilapia nilotica Exposed to Sublethal Dose of Malathion, S[1, 2-Di(EthoxycarbonylEthyl] Dimethyl Phosphorothiolothionate

    Directory of Open Access Journals (Sweden)

    Edna Amparado

    1992-06-01

    Full Text Available Exposure of Tilapia nilotica embryos to sublethal dose of 1.0 ppm commercial grade malathion, S[1,2-di(ethoxycarbonylethyl] dimethyl phosphorothiolothionate from day-10 post fertilization resulted in notochordal aberrations. Pesticide-treated fishes exhibited constriction of the notochordal sheath, folding at the posterior sections and larger notochord than those of the control group.

  14. Modulatory role of dietary Chlorella vulgaris powder against arsenic-induced immunotoxicity and oxidative stress in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zahran, Eman; Risha, Engy

    2014-12-01

    Arsenic intoxicant have long been regarded as an impending carcinogenic, genotoxic, and immunotoxic heavy metal to human and animals as well. In this respect, we evaluated biomarkers of the innate immune response and oxidative stress metabolism in gills and liver of Nile tilapia (Oreochromis niloticus) after arsenic exposure, and the protective role of Chlorella vulgaris (Ch) dietary supplementation were elucidated. Protective role of C. vulgaris (Ch), as supplementary feeds (5% and 10% of the diet) was studied in Nile tilapia (O. niloticus) against arsenic induced toxicity (NaAsO2 at 7 ppm) for 21 days exposure period. A significant down-regulation in innate immune response; including, respiratory burst, lysozyme, and bactericidal activity followed due to deliberately As(+3) exposure. Similarly, oxidative stress response; like nitric oxide (NO), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels were significantly decreased. Combined treatment of Ch and As(+3) significantly enhanced the innate immune response and antioxidant activity. Strikingly, Ch supplementation at 10% has been considered the optimum for Nile tilapia since it exhibited enhancement of innate immune response and antioxidant activity over the level 5%, and even better than that of control level. Thus, our results concluded that dietary Ch supplementation could protect Nile tilapia against arsenic induced immunosuppression and oxidative stresses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Comparative population genetic structure of redbelly tilapia (Coptodon zillii (Gervais, 1848)) from three different aquatic habitats in Egypt

    KAUST Repository

    Soliman, Taha; Aly, Walid; Fahim, Reda M.; Berumen, Michael L.; Jenke-Kodama, Holger; Bernardi, Giacomo

    2017-01-01

    Recently, tilapia have become increasingly important in aquaculture and fisheries worldwide. They are one of the major protein sources in many African countries and are helping to combat malnutrition. Therefore, maintenance and conservation genetics of wild populations of tilapia are of great significance. In this study, we report the population genetic structure and genetic diversity of the redbelly tilapia (Coptodon zillii) in three different Egyptian aquatic environments: brackish (Lake Idku), marine (Al-Max Bay), and freshwater (Lake Nasser). The habitat differences, environmental factors, and harvesting pressures are the main characteristics of the sampling sites. Three mitochondrial DNA markers (COI: cytochrome oxidase subunit I; the D-loop; CYTB: cytochrome b) were used to assess population structure differences among the three populations. The population at Lake Nasser presented the highest genetic diversity (Hd = 0.8116, H = 6), and the marine population of Al-Max Bay the lowest (Hd = 0.2391, H = 4) of the combined sequences. In addition, the phylogenetic haplotype network showed private haplotypes in each environmental habitat. Results presented here will be useful in aquaculture to introduce the appropriate broodstock for future aquaculture strategies of C. zillii. In addition, evidence of population structure may contribute to the management of tilapia fisheries in Egyptian waters.

  16. Live transport of Yellow Perch and Nile Tilapia in AQUI-S 20E (10% Eugenol) at high loading densities

    Science.gov (United States)

    Cupp, Aaron R.; Schreier, Theresa M.; Schleis, Sue M.

    2017-01-01

    Fish transport costs are a substantial portion of the operational expenses for aquaculture facilities in the USA. Safely transporting higher loading densities of fish would benefit haulers by increasing efficiency and reducing costs, but research evaluating transport for individual species is generally lacking. In this study, Yellow Perch Perca flavescens and Nile Tilapia Oreochromis niloticus were transported for 6 h immersed in water containing AQUI-S 20E (10% eugenol) at fish loading densities of 240 g/L (2 lb/gal) for perch and 480 g/L (4 lb/gal) for tilapia. Survival was quantified for fish transported in AQUI-S 20E concentrations of (1) control or 0 mg/L of water, (2) 100 mg/L, or (3) 200 mg/L. Yellow Perch had 98–100% survival, and Nile Tilapia had 100% survival up to through 14 d after transport across all AQUI-S 20E levels, including the control. Eugenol concentrations decreased rapidly in transport tank water, and fish showed no signs of sedation by the end of transport. We conclude that live transport of Yellow Perch and Nile Tilapia at higher loading densities resulted in high survival regardless of the AQUI-S 20E concentrations we tested.

  17. Effects of omnivorous tilapia on water turbidity and primary production dynamics in shallow lakes: implications for ecosystem management

    NARCIS (Netherlands)

    Zhang, Xiufeng; Mei, Xueying; Gulati, Ramesh D.

    2017-01-01

    The introduction of omnivorous tilapia into a variety of aquatic systems worldwide has led to a number of serious ecological problems. One of the main issues is an increase in water turbidity, which affects not only light penetration but also primary production and the distribution of phytoplankton

  18. Characterization of the duodenase-1 gene and its associations with resistance to Streptococuus agalactiae in hybrid tilapia (Oreochromis spp.).

    Science.gov (United States)

    Shen, Yubang; Fu, Gui Hong; Liu, Feng; Yue, Gen Hua

    2015-08-01

    Tilapia is a group of cultured teleost fishes whose production is threatened by some diseases. Identification of DNA markers associated with disease resistance in candidate genes may facilitate to accelerate the selection of disease resistance. The gene encoding a duodenase, which can trigger immune response, has not been studied in fish. We characterized the cDNA of duodenase-1 gene of hybrid tilapia. Its ORF is 759 bp, encoding a serine protease of 252 amino acids. This gene consisted of five exons and four introns. Its expression was detected in all 10 tissues examined, and it was highly expressed in the intestine and kidney. After a challenge with the bacterial pathogen, Streptococcus agalactiae, its expression was up-regulated significantly in the intestine, liver and spleen. We identified seven SNPs in the gene and found that four of them were significantly associated with the resistance to S. agalactiae (P tilapia. The SNP markers in the duodenase-1 gene associated with resistance to the bacterial pathogen, may facilitate the selection of tilapia resistant to the bacterial disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Competitive Interactions between Invasive Nile Tilapia and Native Fish: The Potential for Altered Trophic Exchange and Modification of Food Webs

    Science.gov (United States)

    Martin, Charles W.; Valentine, Marla M.; Valentine, John F.

    2010-01-01

    Recent studies have highlighted both the positive and negative impacts of species invasions. Most of these studies have been conducted on either immobile invasive plants or sessile fauna found at the base of food webs. Fewer studies have examined the impacts of vagile invasive consumers on native competitors. This is an issue of some importance given the controlling influence that consumers have on lower order plants and animals. Here, we present results of laboratory experiments designed to assess the impacts of unintended aquaculture releases of the Nile tilapia (Oreochromis niloticus), in estuaries of the Gulf of Mexico, on the functionally similar redspotted sunfish (Lepomis miniatus). Laboratory choice tests showed that tilapia prefer the same structured habitat that native sunfish prefer. In subsequent interspecific competition experiments, agonistic tilapia displaced sunfish from their preferred structured habitats. When a piscivore (largemouth bass) was present in the tank with both species, the survival of sunfish decreased. Based on these findings, if left unchecked, we predict that the proliferation of tilapia (and perhaps other aggressive aquaculture fishes) will have important detrimental effects on the structure of native food webs in shallow, structured coastal habitats. While it is likely that the impacts of higher trophic level invasive competitors will vary among species, these results show that consequences of unintended releases of invasive higher order consumers can be important. PMID:21200433

  20. Influence of X-rays on oogenesis in Tilapia mossambica. 3. Irradiation of 20 days old larvae

    International Nuclear Information System (INIS)

    Chmilevskij, D.A.

    1985-01-01

    Tilapia mossambica Peters larvae of 20 days old after hatching were irradiated with a dose of 350 R. Gonads recovery in irradiated fishes began from the age of 95 days; anatomic sexual differentiation in gonads delayed; death of developing oocytes was noted: gonads development in the irradiated fishes of 144 days old was sharply suppressed, some fishes were sterile

  1. Bioaccumulation of heavy metals in fish (tilapia zilli and clarias gariepinus) organs from river Benue, North - Central Nigeria

    International Nuclear Information System (INIS)

    Eneji, I.S.; Ato, R.S.; Annune, P.A.

    2011-01-01

    Heavy metals concentrations were determined in fish organs of Tilapia zilli and Clarias gariepinus from River Benue along Makurdi metropolis sing atomic absorption spectrophotometer. The results indicated that Tilapia zilli gills contained the highest concentration (52.2%) of all the detected heavy metals, followed by the intestine (26.3%), while the muscle tissues appeared to be the least preferred site for the bioaccumulation of metals as the lowest metal concentration (21.5%) were detected in this tissue. Similarly, the Clarias gariepinus gills contained the highest concentration (40.3%) of all the detected heavy metals, followed by the intestine (31.6%), while the muscle tissue (28.1%) was the lowest. The trend of heavy metals concentration can be represented as: Cr > Zn > Cu > Fe > Mn > Cd > Pb for Tilapia zilli, while that of Clarias gariepinus was Cr > Zn > Fe > Cu > Mn > Cd > Pb. Tilapia zilli showed high bioaccumulation factors of 244, 229 and 178 for Cr, Zn and Cu, respectively. Claria gariepinus showed 232, 226 and 151 for Cr, Zn and Fe, respectively. This suggests that the fish samples could be used to monitor Cr and Zn pollution levels in the River Benue. (author)

  2. Protective efficacy of cationic-PLGA microspheres loaded with DNA vaccine encoding the sip gene of Streptococcus agalactiae in tilapia.

    Science.gov (United States)

    Ma, Yan-Ping; Ke, Hao; Liang, Zhi-Ling; Ma, Jiang-Yao; Hao, Le; Liu, Zhen-Xing

    2017-07-01

    Streptococcus agalactiae (S. agalactiae) is an important fish pathogen, which has received more attention in the past decade due to the increasing economic losses in the tilapia industry worldwide. As existing effective vaccines of S. agalactiae in fish have obvious disadvantage, to select immunoprotective antigens and package materials would undoubtedly contribute to the development of novel oral vaccines. In the present study, surface immunogenic protein (sip) was selected from the S. agalactiae serovar I a genomes as immunogenic protein in DNA vaccine form with cationic chitosan and biodegradable and biocompatible PLGA. The pcSip plasmid in cationic-PLGA was successfully expressed in tissues of immunized tilapia and the immunogenicity was assessed in tilapia challenge model. A significant increase was observed in the cytokine levels of IL-1β, TNF-α, CC1, CC2 in spleen and kidney tissues. Furthermore, immunized tilapia conferred different levels of protection against challenge with a lethal dose of highly virulent serovar I a S. agalactiae. Our results indicated that the pcSip plasmid in cationic-PLGA induced high level of antibodies and protection against S. agalactiae infection, could be effective oral DNA vaccine candidates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Changes in the quality of fishburger produced from Tilapia ( Oreochromis niloticus ) during frozen storage (-18 degrees C)

    DEFF Research Database (Denmark)

    Tokur, B.; Polat, A.; Beklevik, G.

    2004-01-01

    In this study, the chemical and sensory qualities of fishburger produced from tilapia (Oreochromis niloticus) were investigated during frozen storage (-18 degreesC) over 8 months. The ratios of crude protein, lipid, moisture, crude ash, and polyunsaturated fatty acids in tilapiaburger were found...

  4. Competitive interactions between invasive Nile tilapia and native fish: the potential for altered trophic exchange and modification of food webs.

    Directory of Open Access Journals (Sweden)

    Charles W Martin

    2010-12-01

    Full Text Available Recent studies have highlighted both the positive and negative impacts of species invasions. Most of these studies have been conducted on either immobile invasive plants or sessile fauna found at the base of food webs. Fewer studies have examined the impacts of vagile invasive consumers on native competitors. This is an issue of some importance given the controlling influence that consumers have on lower order plants and animals. Here, we present results of laboratory experiments designed to assess the impacts of unintended aquaculture releases of the Nile tilapia (Oreochromis niloticus, in estuaries of the Gulf of Mexico, on the functionally similar redspotted sunfish (Lepomis miniatus. Laboratory choice tests showed that tilapia prefer the same structured habitat that native sunfish prefer. In subsequent interspecific competition experiments, agonistic tilapia displaced sunfish from their preferred structured habitats. When a piscivore (largemouth bass was present in the tank with both species, the survival of sunfish decreased. Based on these findings, if left unchecked, we predict that the proliferation of tilapia (and perhaps other aggressive aquaculture fishes will have important detrimental effects on the structure of native food webs in shallow, structured coastal habitats. While it is likely that the impacts of higher trophic level invasive competitors will vary among species, these results show that consequences of unintended releases of invasive higher order consumers can be important.

  5. Effects of bamboo substrate and supplemental feeding on growth and production of hybrid red tilapia fingerlings (Oreochromis mossambicusxOrechromis niloticus)

    NARCIS (Netherlands)

    Keshavanath, P.; Gangadhar, B.; Ramesh, T.J.; Dam, van A.A.; Beveridge, M.C.M.; Verdegem, M.C.J.

    2004-01-01

    Periphyton growing on artificial substrates can increase the production of herbivorous fish in aquaculture ponds. Periphyton may be an alternative or a complement for supplemental feed in fingerling production. Growth and production of hybrid red tilapia (Oreochromis mossambicus x Oreochromis

  6. Changes in the physiological parameters, fatty acid metabolism, and SCD activity and expression in juvenile GIFT tilapia (Oreochromis niloticus) reared at three different temperatures.

    Science.gov (United States)

    Ma, X Y; Qiang, J; He, J; Gabriel, N N; Xu, P

    2015-08-01

    We evaluated the effects of rearing temperature on the composition of fatty acids and stearoyl-CoA desaturase (SCD) activity and gene expression in GIFT (genetically improved farmed tilapia) tilapia. Three triplicate groups of fish were reared for 40 days at 22, 28, or 34 °C. At the end of the trial, the final body weight of juveniles reared at 28 °C was higher than that of fish reared at 22 or 34 °C. Feed intake, feed efficiency, and the protein efficiency ratio were also higher at 28 °C. The fatty acid composition of muscle tissue differed significantly (P GIFT tilapia muscle. Additionally, cold acclimation can decrease the content of TC and TG in GIFT tilapia, which can help increase cold tolerance.

  7. A qualitative ecological risk assessment of the invasive Nile tilapia, Oreochromis niloticus in a sub-tropical African river system (Limpopo River, South Africa)

    CSIR Research Space (South Africa)

    Zengeya, TA

    2013-01-01

    Full Text Available This study outlines the development of a qualitative risk assessment method and its application as a screening tool for determining the risk of establishment and spread of the invasive Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), within...

  8. Effects of substrate addition and supplemental feeding on plankton composition and production in tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) polyculture

    NARCIS (Netherlands)

    Uddin, M.S.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.

    2009-01-01

    This study investigated the effects of substrates and supplemental feeding on growth and production of tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in a polyculture system. On actual farms, four treatments were evaluated in triplicate: substrate plus feed (herein

  9. Effects of Dietary Yeast (Saccharomyces cerevisia Supplementation in Practical Diets of Tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    José E. P. Cyrino

    2012-01-01

    Full Text Available A 51-day feeding trial was carried out to determine the effects of various dietary levels of brewer’s yeast, Saccharomyces cerevisiae, in the growth performance, body composition and nutrient utilization in Nile tilapia, Oreochromis niloticus, juveniles. Fish (7.6 ± 0.3 g were stocked into eighteen 1,000-L tanks (100 fish per tank; n = 3 and fed to apparent satiation six isonitrogenous (27% crude protein and isoenergetic (19 kJ/g diets, formulated to contain different dried yeast levels (0%, 10%, 15%, 20%, 30% or 40% diet in substitution to fishmeal. Body weight tripled at the end of the feeding trial for fish fed up to 20% dietary yeast incorporation. Daily growth coefficient (DGC, % body weight/day decreased with increasing dietary yeast level (P < 0.0001. Voluntary feed intake (VFI, %BW/day did not vary significantly with increasing yeast level. Fish fed 40% yeast showed significant reduction in protein efficiency rate, protein retention and nitrogen gain. Increasing levels of dietary yeast did not significantly affect protein or lipid digestibility. Dietary dried yeast was seemingly palatable to tilapia juveniles and was suitable up to 15% inclusion to promote growth and efficient diet utilization, without affecting body composition.

  10. Metabolome strategy against Edwardsiella tarda infection through glucose-enhanced metabolic modulation in tilapias.

    Science.gov (United States)

    Peng, Bo; Ma, Yan-Mei; Zhang, Jian-Ying; Li, Hui

    2015-08-01

    Edwardsiella tarda causes fish disease and great economic loss. However, metabolic strategy against the pathogen remains unexplored. In the present study, GC-MS based metabolomics was used to investigate the metabolic profile from tilapias infected by sublethal dose of E. tarda. The metabolic differences between the dying group and survival group allow the identification of key pathways and crucial metabolites during infections. More importantly, those metabolites may modulate the survival-related metabolome to enhance the anti-infective ability. Our data showed that tilapias generated two different strategies, survival-metabolome and death-metabolome, to encounter EIB202 infection, leading to differential outputs of the survival and dying. Glucose was the most crucial biomarker, which was upregulated and downregulated in the survival and dying groups, respectively. Exogenous glucose by injection or oral administration enhanced hosts' ability against EIB202 infection and increased the chances of survival. These findings highlight that host mounts the metabolic strategy to cope with bacterial infection, from which crucial biomarkers may be identified to enhance the metabolic strategy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. COMPENSATORY GROWTH IN MOZAMBIQUE TILAPIA (Oreochromis mossambicus, FED A SUB-OPTIMAL DIET

    Directory of Open Access Journals (Sweden)

    Ewen McLean

    1998-04-01

    Full Text Available Mozambique tilapia, Oreochromis mossambicus, held in 30%o seawater and at 29-30 °C, were divided into four groups (n = 50/group in replicate, and given one of four feed cycles: 1 control, with continuous feedind, 2 5:5, 3 10:10 and 4 15:15, wherein fish were subjected to starvation and subsequent refeeding cycles of 5, 10 and 15 days respectively. All animals were fed a commercial diet containing 18.4% protein, 6.7% lipid, 58.6% carbohydrate and 7.2% ash, over a 60 day trial period. Growth compensation was observed in the feed cycled groups as increased (P < 0.03 weight specific growth rates during refeeding. However, feed cycled groups were unable to achieve the weghts of control fish. Starvation reduced (P<0.01 haematocrit values when compared to control levels and, in the 15:15 cycled groups, elevated the testicular index (P < 0.02. The results are considered with respect to the commercial application of compensatory growth during production of tilapia.

  12. Anti-androgenic activities of diuron and its metabolites in male Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Silva, Danilo Grünig Humberto da; Batlouni, Sergio Ricardo; Schlenk, Daniel; Almeida, Eduardo Alves de

    2015-07-01

    Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a widely used herbicide which has been frequently detected in surface waters throughout the world. In vivo bioassay guided fractionation studies indicated that diuron may have estrogenic activity augmented by biotransformation. This study evaluated the effects of diuron and three of its metabolites on plasma hormone concentrations and spermatogenesis of the freshwater fish Nile tilapia (Oreochromis niloticus). Sexually mature male fish were exposed for 25 days to diuron, as well to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 200ng/L. Testosterone levels were decreased by diuron, but had limited effects on gonadal histology. Diuron metabolites, however, caused significant decreases in testosterone and in 11-ketotestosterone, gonadosomatic index, diameter of seminiferous tubules and in the mean percentages of germ cells (spermatids and spermatozoa). We conclude that these metabolites have antiandrogenic activity to male Nile tilapia, potentially causing reproductive impairment in male fish. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Growth of monosex hybrid tilapia in the labortory and sewage oxidation ponds

    International Nuclear Information System (INIS)

    Suffern, J.S.; Adams, S.M.; Blaylock, B.G.; Coutant, C.C.; Guthrie, C.A.

    1978-01-01

    Studies were conducted to evaluate the potential of monosex hybrid tilapia (female T. mossambica x male T. hornorum) in waste-heat polyculture systems. The optimum growth temperature for this hybrid was found to be 32 0 C in laboratory experiments. Experiments in sewage pond cage culture in the temperature range of 23 to 33 0 C at stocking densities of approximately 53 fish/m 3 were also conducted. At fish sizes between 5 and 12 cm TL, estimated annual production is approximately 50,000 kg/ha/yr (50,000 lb/acre/yr). Fish in the sewage oxidation ponds grew significantly faster than fish fed trout chow at optimum temperature in the laboratory, even though temperatures in the sewage ponds averaged below the optimum growth temperature. Techniques to accelerate growth rates are being explored. Exposure to gamma radiation (500 rads), known to cause significant increases in channel catfish growth rate, was found to have a similar effect on tilapia. After a 20-week growth period, exposed fish weighed an average of 20% more than controls

  14. Evaluation of thyroid-mediated otolith growth of larval and juvenile tilapia.

    Science.gov (United States)

    Shiao, Jen-Chieh; Wu, Su-Mei; Hwang, Yi-Ping; Wu, Done-Ping; Hwang, Pung-Pung

    2008-06-01

    Thyroid-mediated otolith growth in tilapia was evaluated by the ontogenic triiodothyronine (T3) profile revealed by radioimmunoassay during the first month after hatching. Thyroid hormone receptor genes (TRalpha and TRbeta) were cloned and only the expression of TRalpha mRNA, quantified by real-time PCR, was similar to the T3 profile. Variations in otolith growth showed median correlation with the T3 profile and TRalpha mRNA expression pattern. Hypothyroidism and hyperthyroidism were induced in tilapia juveniles and larvae by administration of different concentrations of thiourea (TU) and T3, respectively, for 13 days. T3 and TU had little effect on otolith growth during the larval stage. However, T3 increased otolith growth and TU retarded, or stopped, otolith growth during the juvenile stage. Furthermore, TU treatment caused permanent changes in otolith shape in the ventral area. Otolith growth recovered slowly from hypothyroidism, requiring 2 days to form an increment during the first week. These results suggest that otolith growth, at least during the juvenile stage, is regulated by the thyroid hormones and the process may be mediated by TRalpha.

  15. Masculinization of nile tilapia (Oreochromis niloticus) using extract of bull testes

    Science.gov (United States)

    Yustiati, A.; Bangkit, I.; Zidni, I.

    2018-03-01

    Tilapia males grow faster to increase the production of the fish, there is a necessity to produce all males by using extract of bull testes. The research method used in this study was the experimental Completely Randomized Design (CRD) with five treatments and three replications. The treatments were A: without immersion and without oral treatment (control); B; immersion 600 μg·L-1 without oral treatment; C: immersion 600 μg·L-1 and oral at a dose of 30 mg·kg-1 feeds, D: immersion 600 μg·L-1 and oral at a dose of 40 mg·kg-1 feeds, E: immersion 600 μg·L-1 and oral at a dose of 50 mg·kg-1 feeds. Results showed that the use of bull testicle extract mixed to media at concentration of 3 ml L-1 produced red male nile of 69.07 %. In addition, the immersion of the extract at 500 μg·L-1 resulted the male of 86.71 %. Sex reversal by dipping at 600 μg·L-1 17α-methyltestosterone combined with oral administration at 40 mg·kg-1 produced the highest male of Nile Tilapia Java carp (86.67 %) compared with dipping, which produced 65.56 % of male. These results suggested that combination of dipping and oral is more effective for sex reversal.

  16. High temperature CO2 capture of hydroxyapatite extracted from tilapia scales

    Directory of Open Access Journals (Sweden)

    Oscar H. Ojeda-Niño

    2017-11-01

    Full Text Available Hydroxyapatite (HAp was obtained from tilapia scales by two extraction methods: direct calcination and acid-base treatment. The physicochemical characteristics of the obtained HAps were evaluated by thermogravimetric analysis, X-ray fluorescence, X-ray diffraction, scanning electron microscopy, surface area, infrared spectroscopy, and basicity measurement at 298 K by CO2-pulse titration. Furthermore, the CO2 capture capacity of the solids at high temperature was also determined. Both methods showed the presence of a HAp phase although significant differences in the properties of the solids were found. The HAp obtained by direct calcination exhibited a lower crystallinity and a greater surface area and basicity than the HAp obtained by the acid-base treatment. These features were correlated with the solid’s CO2 capture capacity. In this work, CO2 capture capacity values for HAp yielded by calcination ranged from 2.5 to 3.2 mg CO2 /g captured at 973 K, and for the acid-base treatment-derived HAp, CO2 capture capacity values between 1.2 to 2.5 mg CO2 /g were recorded. These results reveal the potential of HAps extracted from tilapia scales as solids with high CO2 capture capacity, thermal stability, and capture/release cycles reversibility.

  17. Effects of photoperiod on somatic growth and gonadal development in male nile tilapia

    Directory of Open Access Journals (Sweden)

    Rodrigo Diana Navarro

    2015-10-01

    Full Text Available Rotation and translation of the Earth subject the living organisms to cyclic changes of environmental factors. This study evaluated the effects of photoperiod on growth and gonadal development in Nile tilapia (Oreochromis niloticus. In a completely randomized design experiment, juvenile males were distributed into nine tanks (10 fish per tank and maintained for 60 days under three different light treatments with three repetitions each. The treatments were: T1 - 0 h photoperiod (tanks covered with lids and black plastic; T2 - 12 hours photoperiod (tanks uncovered during photoperiod to provide natural light; and T3 - 24 hours photoperiod (tanks covered with lids equipped with lamps. No significant differences were found between treatments for body length, gonad weight or gonadosomatic index, but body weight was higher in fish subjected to T3 compared with other treatments. Furthermore, significant increases in tubular lumen and germinal epithelium were observed in fish exposed to T1 and T3, respectively. Thus, the manipulation of photoperiod in Nile tilapia culture systems can improve production and consequently increase the economic return on investment.

  18. Hematological and biochemical characters of monosex tilapia (Oreochromis niloticus, Linnaeus, 1758 cultivated using methyltestosterone

    Directory of Open Access Journals (Sweden)

    Alaa El-Din H. Sayed

    2015-10-01

    Full Text Available The use of steroid-treated feeds as 17 α-methyltestosterone for the production of all-male populations is widespread in tilapia aquaculture. The aim of the present study was to investigate the misuse effects of methyltestosterone on monosex farmed Nile tilapia, Oreochromis niloticus by evaluation of hematological and biochemical values. The fishes were obtained from four localities (Assiut as a control, Beheira, Alexandria and Kafr el-Sheikh: three farms from each governorate as farmed monosex produced using methyltestosterone. The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV, white blood cell count, blood platelets, lymphocyte, monocyte, neutrophils and basophils were determined. The results showed that there were changes in the erythrocytic series and in the defense white blood cells. Activities of aspartate aminotransferase (AST, alanine aminotransferase (ALT and alkaline phosphatase (ALP, glucose, cholesterol, total protein, uric acid and creatinine were determined for biochemical study. These alterations are considered an indication for performance and health of fish in the monosex culture medium indicating the side effects of overdose induction of MT.

  19. Haematology and melanoma crophage centers of Nile tilapia fed supplemented diet with propolis

    Directory of Open Access Journals (Sweden)

    Jerko Ledic-Neto

    2014-05-01

    Full Text Available The objective of this study was to investigate the influence of dietary supplementation with propolis on hematology and number and area of melanomacrophage centers in spleen and kidney of tilapia. After acclimation, fish (24.7 ± 7.4 gmean weight were distributed in 6 tanks 100 L, 6 fish per tank, in triplicate, at a temperature 24.0 ± 2.8oC, with two treatments: Fish fed 2% propolis supplemented diet and fish fed non-supplemented diet. To monitor the evolution of the effects, two samples were collected: half of the fish from each treatment were used after 15 days and the other half after 21, composing two feeding times. After each feeding time, blood, spleen and kidney were collected. After twenty one days feeding on 2% propolis supplemented diet, fish showed a lower number of total leukocytes and lymphocytes and an increase in the total erythrocytes number. Fish fed supplemented diet presented an increased number of melanomacrophage centers. We observed hemosiderin in all spleen samples. Kidney showed no significant difference on the presence of melanomacrophage centers containing hemosiderin. Despite these changes, the fish health status was not affected. The results showed that propolis supplementation in the diet ofNile tilapia may be physiologically feasible.

  20. El cultivo de tilapias: una amenaza a las especies ícticas nativas en Nicaragua.

    Directory of Open Access Journals (Sweden)

    McCrary, J.K.

    2001-08-01

    Full Text Available El cultivo de tilapia del nilo (oreochromis niloticus, linnoeus previamente alimentados con hormonas para producir machos, en la laguna de Apoyo en Nicaragua ha permitido la introducción a la laguna de individuos, incluyendo hembras fecundas. Discutimos las consecuencias de esta introducción, en términos de amenazas de extinción de especies endémicas nativas a través de destrucción de hábitat, competencia por sitios de cortejo y alimentación, proliferación de parásitos en poblaciones de fauna nativa, y la depredación de alevines nativos. Mientras que una liberación anterior de una especie similar (O. aureus Steindachner en la laguna de Apoyo, en 1983, tuvo poco impacto observado, este segundo incidente, aquí documentado, ha resultado en dramáticos impactos negativos en la laguna, amenazando especies endémicas locales y creando posiblemente riesgos en la salud humana. Abogamos por la remoción total de tilapias de ecosistemas naturales como el de Apoyo, y advertimos sobre el peligro de las introducciones de especies no nativas en ecosistemas naturales, aun donde introducciones previas han sucedido.

  1. Growth of Nile tilapia Oreochromis niloticus fed with different levels of alcohol yeast.

    Science.gov (United States)

    Medri, V; Pereira, G V; Leonhardt, J H

    2000-02-01

    Two hundred and forty 45-day-old fingerlings of Nile tilapia (Oreochromis niloticus), sexually reverted with an initial average weight of 1.25 +/- 0.14 g, distributed in a totally casualized delineation, during 330 days. The effect of the substitution of 10%, 20% and 30% of the ration by distillery yeast (Saccharomiyces cerevisae) in balanced experimental rations on the development in the breeding of tilapias did not show a harmful effect up to the maximum tested level of 30%, showing that the choice of the yeast in the ration for these fishes depends on the availability and occasional cost. The yeast provides fish with good resistance to unfavorable environmental conditions, which could be verified since there were no statistical differences among the treatments with different levels of yeast and the witness. The long growth rate in terms of length and weight can be attributed to the little available space for each specimen, not obeying the limit of populational density, as well as reduction of food ingestion, which coincide with the winter season, above of the absence of natural feeding.

  2. MICROBIOLOGICAL QUALITY AND SHELF LIFE OF FRESH PACKAGED TILAPIA FILLETS STORED UNDER DIFFERENT CHILL TEMPERATURES

    Directory of Open Access Journals (Sweden)

    Odoli Cyprian

    2013-02-01

    Full Text Available Nile tilapia (Oreochromis niloticus farmed in recirculation aquaculture system (RAS was filleted and packaged in 100% air and 50% CO2: 50% N2 modified atmosphere (MA prior to storage at 1˚C and -1˚C for up to 27 days. Fillets were sampled regularly and analysed for headspace gas composition, sensory and microbial changes. Shelf life varied with apparent relation to storage temperature, package atmosphere and microflora. Pseudomonads were reported as the main spoilage organisms in tilapia fillets during chilled storage conditions. Sensory analysis of cooked samples as well as microbial growth indicated fillets packaged in 100% air had a shelf life of 13-15 days during storage at 1˚C and 20 days at -1˚C. At the end of shelf life in 100% air packaged groups, TVC and pseudomonads counts reached log 7 colony-forming units g-1 in flesh. Whereas in 50% CO2: 50% N2 packaged fillets, the lag phase and generation time of bacteria was extended and recorded counts of < log 4 colony-forming units g-1 up to 27 days of storage at both 1˚C and -1˚C. However, 50% CO2 : 50% N2 conditions restricted fillets shelf life to 23 days based on sensorial changes mainly fillets colour characteristics.

  3. Digestible methionine + cystine requirement for Nile tilapia from 550 to 700 g

    Directory of Open Access Journals (Sweden)

    Mariana Michelato

    2013-01-01

    Full Text Available This trial was conducted to determine the dietary digestible methionine + cystine requirement of Nile tilapia (550 to 700 g based on the ideal protein concept. Six hundred fish were distributed in a completely randomized design with five treatments and four replicates, with 30 fish per experimental unit. The fish were fed diets containing approximately 262 g of digestible protein/kg, 3,040 kcal of digestible energy/kg and 7.90, 9.40, 10.90, 12.40 or 13.90 g of methionine + cystine/kg. The fish were hand-fed three times a day until apparent satiation for 30 days. No effects of dietary methionine + cystine on feed conversion ratio, daily protein deposition, whole body moisture, fillet moisture, crude protein, ether extract and ash, plasmatic HDL and LDL cholesterol were observed. Dietary methionine resulted in a linear increase in whole body protein and linear reduction in lipid deposition rate, hepatosomatic index, whole body ether extract and ash, plasmatic total cholesterol, plasmatic total lipids and plasmatic triglycerides. According to the Linear Response Plateau, the daily weight gain and fillet yield increased up to a level of 9.00 and 9.90 g methionine + cystine/kg of diet, respectively. The digestible methionine + cystine requirement of Nile tilapia is 9.00 g/kg for weight gain and 9.90 g/kg for fillet yield, corresponding to methionine + cystine:lysine ratios of 0.60 and 0.66, respectively.

  4. The LBP Gene and Its Association with Resistance to Aeromonas hydrophila in Tilapia

    Directory of Open Access Journals (Sweden)

    Gui Hong Fu

    2014-12-01

    Full Text Available Resistance to pathogens is important for the sustainability and profitability of food fish production. In immune-related genes, the lipopolysaccharide-binding protein (LBP gene is an important mediator of the inflammatory reaction. We analyzed the cDNA and genomic structure of the LBP gene in tilapia. The full-length cDNA (1901 bp of the gene contained a 1416 bp open reading frame, encoding 471 amino acid residues. Its genomic sequence was 5577 bp, comprising 15 exons and 14 introns. Under normal conditions, the gene was constitutively expressed in all examined tissues. The highest expression was detected in intestine and kidney. We examined the responses of the gene to challenges with two bacterial pathogens Streptcoccus agalactiae and Aeromonas hydrophila. The gene was significantly upregulated in kidney and spleen post-infection with S. agalactiae and A. hydrophila, respectively. However, the expression profiles of the gene after the challenge with the two pathogens were different. Furthermore, we identified three SNPs in the gene. There were significant associations (p < 0.05 of two of the three SNPs with the resistance to A. hydrophila, but not with the resistance to S. agalactiae or growth performance. These results suggest that the LBP gene is involved in the acute-phase immunologic response to the bacterial infections, and the responses to the two bacterial pathogens are different. The two SNPs associated with the resistance to A. hydrophila may be useful in the selection of tilapia resistant to A. hydrophila.

  5. Identification of immunoreactive proteins of Streptococcus agalactiae isolated from cultured tilapia in China.

    Science.gov (United States)

    Liu, Guangjin; Zhang, Wei; Lu, Chengping

    2013-12-01

    Streptococcus agalactiae (Group B streptococcus, GBS) is an important zoonotic pathogen that can cause lethal infections in humans and animals, including aquatic species. Immunoreactive proteins of the S. agalactiae strain, GD201008-001, isolated from cultured tilapia in China, were screened by immunoproteomics using hyperimmune sera, convalescent guinea pig sera and GD201008-001-infected tilapia antisera as primary detection antibodies. A total of 16 different proteins were identified including 13 novel immunoreactive proteins of S. agalactiae. Four proteins, serine-rich repeat glycoprotein 1, branched-chain alpha-keto acid dehydrogenase (BKD) subunit E2, 5'-nucleotidase family protein and ornithine carbamoyltransferase, were shown to react with the three types of sera and thus were considered to represent novel S. agalactiae vaccine candidate antigens. Our findings represent the basis for vaccine development for piscine S. agalactiae and are necessary for understanding virulence factors and immunogenicity of S. agalactiae with different hosts. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  6. Effect of polychlorinated biphenyls on osmoregulatory response and apoptosis in GIFT tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Zheng, Y; Qiu, L; Fan, L; Song, C; Meng, S; Chen, J

    2016-09-02

    In the present study, GIFT tilapia Oreochromis niloticus were exposed to polychlorinated biphenyls (PCBs) for 7, 14, and 21 days. Over the duration of the exposure, genotoxicity and the activity of Na + /K + -ATPase (NKA) and Ca + /Mg + -ATPase (CMA) were measured in the gill, kidney, and intestine, to evaluate changes in osmoregulatory response in O. niloticus. Our results showed significant decreases in organic NKA (except in gill tissues after 0.5 mg/L PCB-exposure) and CMA activity. The results of the genotoxicity assay showed significant increases in atp1a1a, nkcc2 (only in gill tissue), and fxyd7 (except after 21 days of 5 mg/L PCB exposure). We found significant increases in caspase proteins in the liver in the 5-mg/L PCB exposure group, and the transcripts showed dose-dependent increases between treatment groups over the exposure duration. This study presents evidence that chronic exposure to PCB could result in organic osmoregulatory response and hepatic apoptosis in GIFT tilapia.

  7. Effect of Physical Osmosis Methods on Quality of Tilapia Fillets Processed by Heat Pump Drying

    Directory of Open Access Journals (Sweden)

    Li Min

    2017-06-01

    Full Text Available In order to achieve the influence of different pretreatment methods on heat pump dried tilapia fillets, the effects of trehalose, ultrasound-assisted and freeze-thaw cycle assisted osmotic dehydration on the color, rehydration, texture and Ca2+-ATPase activity were investigated. Tilapia fillets (100 mm length × 50 mm width × 5 mm height were first osmoconcentrated in a trehalose solution combined with 4°C under atmospheric pressure for 1 h, different power of ultrasound and freeze-thawing respectively, then heat pump dried. The results showed that under the same drying method, the comprehensive score of ultrasound in 400 Watt was best, compared to freeze-thaw, the ultrasound pretreatment had a significant (p0.05 effect on the rehydration and texture. However, both of them significantly (p<0.05 affected the quality in comparison to that of osmosis at 4°C. It indicates that suitable ultrasonic pretreatment conditions improve the quality of dried products effectively and the conclusion of this research provides reference for heat pump dried similar products.

  8. The aquaculture potential of Tilapia rendalli in relation to its feeding habits and digestive capabilities

    Science.gov (United States)

    Hlophe, S. N.; Moyo, N. A. G.

    Tilapia rendalli is a predominately macrophagous fish. However, it was able to colonise an oligotrophic dam (Flag Boshielo) with limited macrophytes. Therefore, the diet of T. rendalli in this dam was investigated; its stomach contents were examined over 12 months. A size related dietary shift was evident. Juveniles fed mainly on zooplankton while sub-adult and adult fish grazed on both macrophytes and marginal vegetation. T. rendalli’s ability to strive in an environment with limited food resources led to a subsequent study to determine its aquaculture potential. Its growth performance was compared to that of the commonly cultured Oreochromis mossambicus. Juveniles of both species were fed a commercial tilapia diet for 60 days. Specific growth rate and protein efficiency ratio was comparable to that of O. mossambicus (P > 0.05, ANOVA). Feed conversion ratio was significantly higher (P 0.05). Amylase activities were significantly higher (P < 0.05) in T. rendalli than in O. mossambicus. The highest amylase activities were recorded in the proximal intestines as 26.34 and 22.00 μmol/min/mg protein in T. rendalli and O. mossambicus respectively. This may be an indicator that T. rendalli is better equipped to digest plant diets. T. rendalli may be the aquaculture species of choice for emerging fish farmers who cannot afford the highly priced fishmeal as a protein source in fish diets.

  9. Body composition and compensatory growth in Nile tilapia Oreochromis niloticus under different feeding intervals

    Science.gov (United States)

    Gao, Yang; Wang, Ziwei; Hur, Jun-wook; Lee, Jeong-Yeol

    2015-07-01

    We investigated the growth and body composition of Nile tilapia under five different feeding regimes. A control group was fed to satiation twice daily for 185 days; four treatment groups were fed at intervals of 2, 3, 4 or 7 days (dietary `restricted' period, days 0-80) and then fed to satiation (`refeeding' period, days 80-185). Compensatory growth in weight and length of the feed-restricted groups was observed during the refeeding period. However, the growth of none of the restricted groups caught up with that of the control group over the experimental period. Feed intake upon refeeding increased with the duration of deprivation. There were no significant differences in feed efficiency between the restricted and control groups during the refeeding stage, suggesting that hyperphagia was the mechanism responsible for the increased growth rates during this period. Tilapia preferentially used n-3 polyunsaturated fatty acids and nonessential amino acids during the restricted-feeding period. Higher production was achieved by higher feed consumption. We suggest that if attainment of market size in minimum time is required, fish should be consistently fed to satiation, while taking care to avoid the possible negative consequences of overfeeding.

  10. Syncytial Hepatitis of Tilapia ( Oreochromis niloticus L.) is Associated With Orthomyxovirus-Like Virions in Hepatocytes.

    Science.gov (United States)

    Del-Pozo, J; Mishra, N; Kabuusu, R; Cheetham, S; Eldar, A; Bacharach, E; Lipkin, W I; Ferguson, H W

    2017-01-01

    Using transmission electron microscopy (TEM), the presented work expands on the ultrastructural findings of an earlier report on "syncytial hepatitis," a novel disease of tilapia (SHT). Briefly, TEM confirmed the presence of an orthomyxovirus-like virus within the diseased hepatocytes but not within the endothelium. This was supported by observing extracellular and intracellular (mostly intraendosomal), 60-100 nm round virions with a trilaminar capsid containing up to 7 electron-dense aggregates. Other patterns noted included enveloped or filamentous virions and virion-containing cytoplasmic membrane folds, suggestive of endocytosis. Patterns atypical for orthymyxovirus included the formation of syncytia and the presence of virions within the perinuclear cisternae (suspected to be the Golgi apparatus). The ultrastructural morphology of SHT-associated virions is similar to that previously reported for tilapia lake virus (TiLV). A genetic homology was investigated using the available reverse transcriptase polymerase chain reaction (RT-PCR) probes for TiLV and comparing clinically sick with clinically normal fish and negative controls. By RT-PCR analysis, viral nucleic acid was detected only in diseased fish. Taken together, these findings strongly suggest that a virus is causally associated with SHT, that this virus shares ultrastructural features with orthomyxoviruses, and it presents with partial genetic homology with TiLV (190 nucleotides).

  11. The motility and motion duration of jatimbulan tilapia (Oreochromis niloticus) spermatozoa in different salinity

    Science.gov (United States)

    Triastuti, J.; Kintani, D.; Luqman, E. M.; Pujiastuti, D. Y.

    2018-04-01

    Tilapia hatchery is still conducted in freshwater and seeds are death simultaneousy when cultivated in high salinity due to the acclimatization process. An alternative method to implement hatchery at high salinity is required. This study aims to determine the salinity of activation medium that provides the best Jatimbulan Tilapia sperm motility and motion duration at high salinity. The study applies completely randomized design (CRD), which consists of 5 treatments (0 ppt, 4 ppt, 9 ppt, 14 ppt and 19 ppt) and 4 repetitions. The parameters consists of sperm motility, motion duration, fresh sperm data (volume, color, odor, pH, consistency, and the concentration of sperm) and sperm abnormalities. The results exhibited that salinity significantly (p < 0.05). Influeneed the sperm motility and motion duration. Motility reaches its best at 0 ppt and 4 ppt (93.4 % and 87.8 %). For motion duration, best condition was in 0 ppt and 4 ppt treatments, totaling 2128 seconds and 1961.5 seconds. Meanwhile, sperm did not move when treated in waters with 9 ppt, 14 ppt and 19 ppt salinities.

  12. The Antibacterial and Antioxidant Effect of Grape Seed and Green Tea Extracts on Durability of Tilapia

    Directory of Open Access Journals (Sweden)

    Rozita Golvardzadeh

    2016-10-01

    Full Text Available Background: The current study tried to investigate the antioxidant and anti-bacterial effects of green tea and grape seed extract (with a volume of 2% on durability of Tilapia packed inpolyethylene bags, which were kept in cool temperature of 4 ± 1 °C. Methods: Prepared fish were divided into 3 batches: 2 batches were treated by dipping for 30 min in ethanolic of green tea extract (2% v/v and grape seed (2% v/v, respectively, while the third batch was dipped in distilled water as a control sample. The control and treated fish samples were analyzed for microbiological such as total volatile count and psychrotrophic count, and chemical such as thiobarbituric acid (TBA, and free fatty acid (FFA values. The sensory characteristic was over a period of 20 days. Results: The results indicated that the two extracts' treatments delayed significantly (P < 0.05. Lipid oxidation and process of spoilage in comparison with the psychrotrophic bacteria and total viable count control also remained lower than the proposed acceptable limit (7 log CFU/g. According to sensory, chemical, and microbiological analyses results, the treatment of grape seed extract had high quality and enhanced the beneficial effects on sensory characteristics in comparison with other treatments. Conclusions: the present study showed that the grape seed extract and green tea were very effective in extending the shelf life of Tilapia during refrigerated storage.

  13. Effects of enzyme complex SSF (solid state fermentation in pellet diets for Nile tilapia

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    Guilherme de Souza Moura

    2012-10-01

    Full Text Available The effects of enzyme complex SSF (solid state fermentation on growth performance and the availability of sucrose and monosaccharides in the chyme of Nile were involved. The study included 360 fish (70g±4.43 in a completely randomized design with six dietary treatments (0, 50, 100, 150, 200 and 250 ppm of SSF arranged in six replicates, with 10 fish per replicate. Every 15 days, one tilapia of each experimental unit was sacrificed for analyses of carbohydrate in the chyme. On day 60 of the experiment, the performance parameters were measured. There was a linear effect according to treatment for final weight and weight gain. For the other performance parameters, there were no differences. There was quadratic effect for sucrose and glucose in function of the treatment, whereas the fructose levels increased linearly. The addition of 150 ppm of the enzyme complex SSF in the feed improves the performance of Nile tilapia and increases the availability of sucrose and monosaccharides in the chyme.

  14. Estrogenic activities of diuron metabolites in female Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Felício, Andreia Arantes; Batlouni, Sergio Ricardo; Schlenk, Daniel; de Almeida, Eduardo Alves

    2016-03-01

    Some endocrine disrupting chemicals (EDCs) can alter the estrogenic activities of the organism by directly interacting with estrogen receptors (ER) or indirectly through the hypothalamus-pituitary-gonadal axis. Recent studies in male Nile tilapia (Oreochromis niloticus) indicated that diuron may have anti-androgenic activity augmented by biotransformation. In this study, the effects of diuron and three of its metabolites were evaluated in female tilapia. Sexually mature female fish were exposed for 25 days to diuron, as well as to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 100 ng/L. Diuron metabolites caused increases in E2 plasma levels, gonadosomatic indices and in the percentage of final vitellogenic oocytes. Moreover, diuron and its metabolites caused a decrease in germinative cells. Significant differences in plasma concentrations of the estrogen precursor and gonadal regulator17α-hydroxyprogesterone (17α-OHP) were not observed. These results show that diuron metabolites had estrogenic effects potentially mediated through enhanced estradiol biosynthesis and accelerated the ovarian development of O. niloticus females. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Trace metal concentrations in Tilapia fed with pig and chicken manure

    Energy Technology Data Exchange (ETDEWEB)

    Wong, M.H.; Chan, K.M.; Liu, W.K.

    1984-01-01

    The present experiment investigated the effects of adding pig manure and chicken manure as supplementary feeds for rearing Sarotherodon mossambicus (Tilapia mossambica) in the laboratory. The feeding test lasted for four weeks under stable aerated conditions. Various portions (10%, 40%, 60% w/w) of the two types of manure were mixed with dried tubifex worm pellets, whilst the control group consisted of tubifex worm alone. The metals studied were Mn, Fe, Cu and Pb. The diets supplemented with 40% and 60% manure contained significantly (p < 0.05) greater amounts of all the metals tested except iron. The concentration of metals in the fish tissues (gill, viscera, flesh) was related to the amount of manure supplement. Harmful effects were reflected by significantly lower (p < 0.05) protein content in fish fed on manure-supplement diets, with the sole exception of the 10% pig manure supplement. Histological damage was also observed in the gills and the hepatopancreas of fish fed on diets supplemented with 60% pig manure and with 40% or 60% chicken manure. Of the two kinds of animal manure investigated as potential supplementary feeds for rearing tilapia, the results indicate that pig manure is likely to be the better choice.

  16. Analysis of Heavy Metals in Water and Fish (Tilapia sp.) Samples from Tasik Mutiara, Puchong

    International Nuclear Information System (INIS)

    Ismaniza Ismail; Idaliza Mat Saleh

    2012-01-01

    The concentrations of seven heavy metals (Al, As, Cd, Cu, Fe, Pb and Zn) were detected in muscle tissues of Tilapia sp. (black tilapia) collected from the lake of Taman Mutiara, Puchong. Samples were collected for several months in the end of 2009 at three sampling points. Heavy metals in fish and water samples were analyzed by Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP-OES). Only Al, Cu, Fe and Zn were detected in the order Fe > Zn > Al > Cu, whereas concentrations of As, Cd and Pb were below the detection limit. The concentrations of heavy metals in water samples were low and below the detection limit. The levels of heavy metals in the fish samples can be considered as a serious matter of concern as it may be consumed and it signifies the degradation of lake quality. Generally, the sources of heavy metals in the Tasik Mutiara, Puchong could be attributed to the illegal waste dumping activity and discharge from the nearby sewage treatment plant into the lake which promote eutrophication in the lake. It could also be attributed to the Low Dissolved Oxygen (DO) levels in the lake. (author)

  17. The LBP Gene and Its Association with Resistance to Aeromonas hydrophila in Tilapia

    Science.gov (United States)

    Fu, Gui Hong; Liu, Feng; Xia, Jun Hong; Yue, Gen Hua

    2014-01-01

    Resistance to pathogens is important for the sustainability and profitability of food fish production. In immune-related genes, the lipopolysaccharide-binding protein (LBP) gene is an important mediator of the inflammatory reaction. We analyzed the cDNA and genomic structure of the LBP gene in tilapia. The full-length cDNA (1901 bp) of the gene contained a 1416 bp open reading frame, encoding 471 amino acid residues. Its genomic sequence was 5577 bp, comprising 15 exons and 14 introns. Under normal conditions, the gene was constitutively expressed in all examined tissues. The highest expression was detected in intestine and kidney. We examined the responses of the gene to challenges with two bacterial pathogens Streptcoccus agalactiae and Aeromonas hydrophila. The gene was significantly upregulated in kidney and spleen post-infection with S. agalactiae and A. hydrophila, respectively. However, the expression profiles of the gene after the challenge with the two pathogens were different. Furthermore, we identified three SNPs in the gene. There were significant associations (p tilapia resistant to A. hydrophila. PMID:25470022

  18. Genome-wide methylation analysis identified sexually dimorphic methylated regions in hybrid tilapia

    Science.gov (United States)

    Wan, Zi Yi; Xia, Jun Hong; Lin, Grace; Wang, Le; Lin, Valerie C. L.; Yue, Gen Hua

    2016-01-01

    Sexual dimorphism is an interesting biological phenomenon. Previous studies showed that DNA methylation might play a role in sexual dimorphism. However, the overall picture of the genome-wide methylation landscape in sexually dimorphic species remains unclear. We analyzed the DNA methylation landscape and transcriptome in hybrid tilapia (Oreochromis spp.) using whole genome bisulfite sequencing (WGBS) and RNA-sequencing (RNA-seq). We found 4,757 sexually dimorphic differentially methylated regions (DMRs), with significant clusters of DMRs located on chromosomal regions associated with sex determination. CpG methylation in promoter regions was negatively correlated with the gene expression level. MAPK/ERK pathway was upregulated in male tilapia. We also inferred active cis-regulatory regions (ACRs) in skeletal muscle tissues from WGBS datasets, revealing sexually dimorphic cis-regulatory regions. These results suggest that DNA methylation contribute to sex-specific phenotypes and serve as resources for further investigation to analyze the functions of these regions and their contributions towards sexual dimorphisms. PMID:27782217

  19. Efficient and Heritable Gene Targeting in Tilapia by CRISPR/Cas9

    Science.gov (United States)

    Li, Minghui; Yang, Huihui; Zhao, Jiue; Fang, Lingling; Shi, Hongjuan; Li, Mengru; Sun, Yunlv; Zhang, Xianbo; Jiang, Dongneng; Zhou, Linyan; Wang, Deshou

    2014-01-01

    Studies of gene function in non-model animals have been limited by the approaches available for eliminating gene function. The CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR associated) system has recently become a powerful tool for targeted genome editing. Here, we report the use of the CRISPR/Cas9 system to disrupt selected genes, including nanos2, nanos3, dmrt1, and foxl2, with efficiencies as high as 95%. In addition, mutations in dmrt1 and foxl2 induced by CRISPR/Cas9 were efficiently transmitted through the germline to F1. Obvious phenotypes were observed in the G0 generation after mutation of germ cell or somatic cell-specific genes. For example, loss of Nanos2 and Nanos3 in XY and XX fish resulted in germ cell-deficient gonads as demonstrated by GFP labeling and Vasa staining, respectively, while masculinization of somatic cells in both XY and XX gonads was demonstrated by Dmrt1 and Cyp11b2 immunohistochemistry and by up-regulation of serum androgen levels. Our data demonstrate that targeted, heritable gene editing can be achieved in tilapia, providing a convenient and effective approach for generating loss-of-function mutants. Furthermore, our study shows the utility of the CRISPR/Cas9 system for genetic engineering in non-model species like tilapia and potentially in many other teleost species. PMID:24709635

  20. Application of Lactic Acid Bacteria (LAB) in freshness keeping of tilapia fillets as sashimi

    Science.gov (United States)

    Cao, Rong; Liu, Qi; Chen, Shengjun; Yang, Xianqing; Li, Laihao

    2015-08-01

    Aquatic products are extremely perishable food commodities. Developing methods to keep the freshness of fish represents a major task of the fishery processing industry. Application of Lactic Acid Bacteria (LAB) as food preservative is a novel approach. In the present study, the possibility of using lactic acid bacteria in freshness keeping of tilapia fillets as sashimi was examined. Fish fillets were dipped in Lactobacillus plantarum 1.19 (obtained from China General Microbiological Culture Collection Center) suspension as LAB-treated group. Changes in K-value, APC, sensory properties and microbial flora were analyzed. Results showed that LAB treatment slowed the increase of K-value and APC in the earlier storage, and caused a smooth decrease in sensory score. Gram-negative bacteria dominated during refrigerated storage, with Pseudomonas and Aeromonas being relatively abundant. Lactobacillus plantarum 1.19 had no obvious inhibitory effect against these Gram-negatives. However, Lactobacillus plantarum 1.19 changed the composition of Gram-positive bacteria. No Micrococcus were detected and the proportion of Staphylococcus decreased in the spoiled LAB-treated samples. The period that tilapia fillets could be used as sashimi material extended from 24 h to 48 h after LAB treatment. The potential of using LAB in sashimi processing was confirmed.

  1. Reproductive performance of female Nile tilapia ( Oreochromis niloticus fed diets with different digestible energy levels

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    Tamira Maria Orlando

    Full Text Available ABSTRACT This study aimed to evaluate the reproductive performance of female Nile tilapia (Oreochromis niloticus fed diets containing different levels of digestible energy (DE. The fish were housed in 15 fiberglass tanks (500 L in a recirculating system at an average temperature of 27.5 °C. The treatments consisted of five diets with increasing levels of DE (3,200; 3,400; 3,600; 3,800; and 4,000 kcal/kg. The levels of DE did not significantly influence the final weight or the hepatosomatic, gonadosomatic, and visceral fat indices. The absolute fecundity was influenced by the treatments, for which the highest values were observed from the 3,600 kcal/kg DE level and upward. The proximate composition of the fish also had a significant effect on the variables crude protein, ether extract, and ash; the fish fed diets with higher levels of DE exhibited the lowest body protein content, while the accumulation of ether extract exhibited the opposite response. A level of 3,600 kcal/kg of digestible energy should be used in diets with 380 g/kg crude protein and a starch/lipid ratio of 1.33 for female Nile tilapia.

  2. Tilapia-waste flour as a natural nutritional replacer for bread: A consumer perspective.

    Directory of Open Access Journals (Sweden)

    Maria Lúcia G Monteiro

    Full Text Available Six bread formulations with different levels of tilapia-waste flour (BTF0%, BTF2.5%, BTF5%, BTF10%, BTF15%, and BTF20% were analyzed for nutritional composition and sensory characterization. Tilapia-waste flour (TF increased (P < 0.05 the lipid, protein and ash contents, and decreased (P < 0.05 the levels of carbohydrates and total dietary fiber. BTF0%, BTF2.5% and BTF5% received the highest (P < 0.05 scores for acceptance and preference. Despite this apparent consumer preference for low or no levels, TF can be added to bread at levels below 12.17% (P < 0.05 without triggering consumer rejection. TF changed (P < 0.05 the sensory characterization of bread because of a disagreeable flavor, aroma, and texture; however, airy appearance, sticky in the teeth and cream color did not influence the overall liking. TF at 5% enhanced the nutritional value while maintaining acceptable sensory scores for bread, constituting a potential strategy to satisfy consumer and industry requirements.

  3. THE OPTIMAL RATIO OF NILE TILAPIA (Oreochromis niloticus AND COMMON CARP (Cyprinus carpio FOR IMPROVING PRODUCTIVITY ON DEEP WATER POND

    Directory of Open Access Journals (Sweden)

    Imam Taufik

    2013-06-01

    Full Text Available Pond productivity can be increased by applied polyculture system in the deep pond. The purpose of this experiment is to examine the optimal ratio between nile tilapia and common carp, in order to increase the productivity. Nine concrete tanks (15 m2 with water depth of 2.2 m and were completed by water inlet, water outlet, and aeration. Both of nile tilapia and common carp with size ranging of 5-8 cm in total length were used. Stock density was 150 ind./m2. The difference ratio of both fish tilapia and carp of fish stocked as a treatment. The fish ratio this experiment were as followed: A 100%; B 80%:20%; C 60%:40%. Fish fed by pellet until at ad libitum. The duration of experiment was 100 days. Parameters such as survival, growth, and productivity were observed every ten days during the experiment period. Water quality parameters were also periodically observed. The results showed that survival of nile tilapia among the treatments were not significantly different (P>0.05 where survival of common carp at B treatment was better than C treatment (P<0.05. The highest of growth of absolute weight (94.86±2.85 g and total length (14.71±1 cm of nile tilapia at B treatment was found (P<0.05 where the best of growth of absolute weight (106.52±10.47 g and total length (11.57±1.78 cm of common carp was also found at B treatment (P<0.05. Biomass productivity at B treatment was the highest compared with A treatment (P<0.05. Combination between polyculture and the deep water pond technology could increase productivity. The polyculture system and the deep water pond technology would be able to keep constant water quality within in the threshold accordance with the regulation for fish culture.

  4. Mapping QTL for Sex and Growth Traits in Salt-Tolerant Tilapia (Oreochromis spp. X O. mossambicus).

    Science.gov (United States)

    Lin, Grace; Chua, Elaine; Orban, Laszlo; Yue, Gen Hua

    2016-01-01

    In aquaculture, growth and sex are economically important traits. To accelerate genetic improvement in increasing growth in salt-tolerant tilapia, we conducted QTL mapping for growth traits and sex with an F2 family, including 522 offspring and two parents. We used 144 polymorphic microsatellites evenly covering the genome of tilapia to genotype the family. QTL analyses were carried out using interval mapping for all individuals, males and females in the family, respectively. Using all individuals, three suggestive QTL for body weight, body length and body thickness respectively were detected in LG20, LG22 and LG12 and explained 2.4% to 3.1% of phenotypic variance (PV). When considering only males, five QTL for body weight were detected on five LGs, and explained 4.1 to 6.3% of PV. Using only females from the F2 family, three QTL for body weight were detected on LG1, LG6 and LG8, and explained 7.9-14.3% of PV. The QTL for body weight in males and females were located in different LGs, suggesting that in salt-tolerant tilapia, different set of genes 'switches' control the growth in males and females. QTL for sex were mapped on LG1 and LG22, indicating multigene sex determination in the salt-tolerant tilapia. This study provides new insights on the locations and effects of QTL for growth traits and sex, and sets the foundation for fine mapping for future marker-assisted selection for growth and sex in salt-tolerant tilapia aquaculture.

  5. Effects of methomyl on steroidogenic gene transcription of the hypothalamic-pituitary-gonad-liver axis in male tilapia.

    Science.gov (United States)

    Meng, ShunLong; Qiu, LiPing; Hu, GengDong; Fan, LiMin; Song, Chao; Zheng, Yao; Wu, Wei; Qu, JianHong; Li, DanDan; Chen, JiaZhang; Xu, Pao

    2016-12-01

    Male tilapia were exposed to sub-lethal methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 d, and were subsequently cultured in methomyl-free water for 18 d. Relative transcript abundance of steroidogenic genes involved in the HPGL axis of male tilapia was examined at 30 d in the exposure test and at 18 d in the recovery test. The results revealed that low concentrations of methomyl (0.2 and 2 μg/L) did not cause significant changes in gene mRNA levels in the HPGL axis of male tilapia; thus, we considered 2 μg/L concentrations as the level that showed no apparent adverse endocrine disruption effects. However, higher concentrations of methomyl (20 and 200 μg/L) disrupted the endocrine system and caused significant increase in the levels of GnRH2, GnRH3, ERα, and ERβ genes in the hypothalamus, GnRHR and FSHβ genes in the pituitary, CYP19a, FSHR, and ERα genes in the testis, and VTG and ERα genes in the liver, and significantly decreased the levels of LHR, StAR, 3β-HSD, and ARα genes in the testis and LHβ gene in the pituitary, leading to changes in sex steroid hormone and vitellogenin levels in the serum and ultimately resulting in reproductive dysfunction in male tilapia. The recovery tests showed that the toxicity effect caused by 20 μg/L methomyl was reversible; however, the toxicity effect at 200 μg/L of methomyl was irreversible after 18 d. Therefore, we concluded that 200 μg/L was the threshold concentration for methomyl-induced irreversible endocrine disruption in male tilapia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Treatments of tilapia (Oreochromis niloticus) using nitric oxide for quality improvement: Establishing a potential method for large-scale processing of farmed fish.

    Science.gov (United States)

    Wang, Zi-Chao; Yan, Yuzhen; Su, Ping; Zhao, Mou-Ming; Xia, Ning; Chen, De-Wei

    2018-07-01

    To find a succedaneum of present methods for slaughtering tilapia, we have demonstrated the influence of nitric oxide (NO) (saturated NO solution) through euthanasia before slaughter on the animal welfare and muscle color of tilapia. The results suggested that NO euthanasia significantly improved the animal welfare and muscle color. Besides, the investigation of NO postmortem treatment on the muscle color and color stability of tilapia fillets suggested that NO postmortem treatment not only improved the muscle color and color stability but also prolonged the shelf-life of tilapia fillets during the refrigerated storage. To further investigate the effect of NO euthanasia on the quality of tilapia fillets and to estimate the safety of NO treatments (NO euthanasia and NO postmortem treatment) for the application of NO treatments in industrial manufacturing of tilapia and possibly of other fish species. NO euthanasia was adopted in this study following a simulated fish processing line. HbNO and MbNO values were measured to clarify the mechanism and process of NO euthanasia. The blood parameters, muscle pH, rigor index, drip loss and total volatile basic nitrogen (TVB-N) values were measured to evaluate the quality of the fillets obtained from NO euthanized tilapia. Besides, the nitrate (NO 3 - ) levels in the muscles after the refrigerated storage were detected to estimate the food safety of both NO euthanasia and NO postmortem treatment. Fillets obtained from the tilapia euthanized by NO showed a later reduction of muscle pH, a later onset of rigor mortis postmortem and less drip loss during the refrigerated storage than control. NO euthanasia caused less TVB-N than control and prolonged the shelf life of tilapia fillets. Moreover, the NO 3 - levels in the muscles of both NO euthanasia and NO postmortem treatment after the refrigerated storage were below the maximum permitted limit. Both the NO euthanasia and NO postmortem treatment are suitable for improving the

  7. Cymothoa indica (Isopoda; Cymothoidae and Alitropus typus (Isopoda; Aegidae on freshwater fish Tilapia mossambica (Cichlidae in Vellar estuary, Southeast coast of India

    Directory of Open Access Journals (Sweden)

    G. Rameshkumar

    2010-09-01

    Full Text Available The study was carried out to establish the extent of double parasitation of two species of isopods Cymothoa indica and Alitropus typus on Tilapia mossambica. Cymothoa indica, a typical Indo-Pacific genus, and A. typus, a common crustacean parasite of fish in Southeast Asia, which feeds by sucking blood species, are reported by the first time in the freshwater fish Tilapia from Vellar estuary.

  8. Caracterización de coproductos de la industria del fileteado de tilapia nilótica (oreochromis niloticus) y trucha arcoíris (oncorhynchus mykiss) en colombia

    OpenAIRE

    Osorio, A.; Wills, A.; Muñoz, A. P.

    2013-01-01

    La industria del fileteado de tilapia y trucha genera cantidades significativas de coproductos de los cuales no existe suficiente información disponible sobre su composición y calidad. Esta investigación determinó algunos componentes nutricionales y microbiológicos de coproductos obtenidos en plantas exportadoras de filetes de tilapia nilótica y trucha arcoíris en Colombia. El esqueleto mostró el mayor aporte de cenizas (tilapia: 14,12 ± 0,16%; trucha: 6,18 ± 0,06%), calcio (tilapia: 5,7...

  9. Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Sarker, Pallab K.; Kapuscinski, Anne R.; Lanois, Alison J.; Livesey, Erin D.; Bernhard, Katie P.; Coley, Mariah L.

    2016-01-01

    We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc) to determine the optimum level of fish-oil substitution (partial or complete) for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet), we found significantly higher weight gain and protein efficiency ratio (PER), and lower (improved) feed conversion ratio (FCR) and feed intake compared to a control diet containing fish oil (Sc0); and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds. PMID:27258552

  10. Colorimetric Method of Loop-Mediated Isothermal Amplification with the Pre-Addition of Calcein for Detecting Flavobacterium columnare and its Assessment in Tilapia Farms.

    Science.gov (United States)

    Suebsing, Rungkarn; Kampeera, Jantana; Sirithammajak, Sarawut; Withyachumnarnkul, Boonsirm; Turner, Warren; Kiatpathomchai, Wansika

    2015-03-01

    Flavobacterium columnare, the causative agent of columnaris disease in fish, affects many economically important freshwater fish species. A colorimetric method of loop-mediated isothermal amplification with the pre-addition of calcein (LAMP-calcein) was developed and used to detect the presence of F. columnare in farmed tilapia (Nile Tilapia Oreochromis niloticus and red tilapia [Nile Tilapia × Mozambique Tilapia O. mossambicus]) and rearing water. The detection method, based on a change in color from orange to green, could be performed within 45 min at 63°C. The method was highly specific, as it had no cross-detections with 14 other bacterial species, including other fish pathogens and two Flavobacterium species. The method has a minimum detection limit of 2.2 × 10(2) F. columnare CFU; thus, it is about 10 times more sensitive than conventional PCR. With this method, F. columnare was detected in gonad, gill, and blood samples from apparently healthy tilapia broodstock as well as in samples of fertilized eggs, newly hatched fry, and rearing water. The bacteria isolated from the blood were further characterized biochemically and found to be phenotypically identical to F. columnare. The amplified products from the LAMP-calcein method had 97% homology with the DNA sequence of F. columnare.

  11. [Centrocestus formosanus (Opisthorchiida: Heterophyidae) as a cause of death in gray tilapia fry Oreochromis niloticus (Perciforme: Cichlidae) in the dry Pacific of Costa Rica].

    Science.gov (United States)

    Arguedas Cortés, Donald; Dolz, Gaby; Romero Zúñiga, Juan J; Jiménez Rocha, Ana E; León Alán, Dennis

    2010-12-01

    Centrocestusformosanus is a zoonotic trematode from Asia and has been mainly associated as cause of death of cultured fish. To identify pathogen trematode species in tilapia fry (Oreochromis niloticus) and to determine mollusks hosting these parasites, freshwater mollusks were collected from tilapia cultured ponds and experimental infections were carried out with tilapia fries and different mollusk species. A total of 907 freshwater mollusks were obtained from tilapia ponds and were identified to species level, four gastropods and one bivalve were determined: Melania tuberculata, Melanoides turricula, Pomacea flagellata, Haitia cubensis and Anodontiles luteola. For the first time, the presence of M. turricula and H. cubensis are reported in Costa Rica. Seven morphotypes of cercariae (Xifiodiocercaria, Equinostoma, Oftalmocercaria, Parapleurolofocercus, Cistocerca, Furcocercaria and Leptocercaria) parasitizing all five species of mollusks were found, all of distome type. Experimental exposure of tilapia fry to M. tuberculata demonstrated that the parapleurolofocercus morphotype found in the mollusk is in accordance with the finding of C. formosanus in tilapia fry. An abundance and mean intensity of 1018-1027 digeneans per gill in each exposed fish was determined. Centrocestus formosanus is reported for the first time in Costa Rica, for which the primary and secondary intermediate hosts were also determined.

  12. The identification of plankton, water quality, blood cell, and histology in culture pond of tilapia Oreochromis niloticus which infected by viral nervous necrosis (VNN)

    Science.gov (United States)

    Yanuhar, U.; Rahayu, D. T.; Musa, M.; Arfiati, D.

    2018-04-01

    Currently, Viral Nervous Necrotic (VNN) is not only attacking the marine fish but also the freshwater fish like tilapia (Oreochromis niloticus). The aims of study to identify the type of plankton, water quality status, blood cell status, also histology of VNN infected tilapia obtained in culture ponds. The methods included plankton identification and water quality analysis from the infected fish pond in the Krakal, Blitar. The quality of blood cells and the histology of tilapia infected by VNN observed using a microscope with Hematoxylin-Eosin staining. The result show plankton in a fish pond of infected tilapia includes 3 divisions: Chlorophyta, Cyanophyta, and Bacillariophyta and 2 phyla: Arthropoda, and Rotifera. The values of erythrocyte, hematocrit, and hemoglobin were smaller than normal tilapia, however, the leukocyte and macronucleus values of VNN-infected fish were higher than normal fish. The fish histology shows the vacuolation in the brain and eyes tissue. The water quality of the culture pond have the temperature, pH, turbidity, DO, CO2, NO3, PO4, TOM in the range of 30-32°C 7.0-9.0; 25cm; 6.082–7.44mg/L 3.98–9.08mg/L 1.039–1.139 mg/L; 0.051-0.054mg/L; and 11.377-13.905mg/L, respectively. VNN causing high leukocyte and macronuclei and the damaging in brain and eyes tissue in infected tilapia.

  13. Selección masal por peso y coloración en tilapia roja Mass selection by weight and coloration in red tilapia

    Directory of Open Access Journals (Sweden)

    María Alejandra Ruiz Peña

    2009-04-01

    Full Text Available Para evaluar la efectividad de la selección masal por color y peso se analizaron dos generaciones (G1 y G2 de alevinos de tilapia roja Oreochromis sp. De 40.000 larvas a la sexta semana se eliminaron los alevinos manchados y blancos y a las 14 semanas se separaron por sexos. Se midió el peso (g, la longitud total (cm, la altura (cm y el ancho (cm de 150 individuos a las 6, 14 y 24 semanas de edad. En la semana 24 se escogieron 150 machos y 450 hembras con las coloraciones deseables y mayor peso. La selección resultó efectiva para coloración en G2, puesto que la proporción de individuos rojos se incrementó en 15% con respecto a los testigos. Entre generaciones (G1 y G2 el efecto de la selección fue positivo, debido a que la proporción de rojos se incrementó de 64% a 84% y se redujo la de manchados de 31% a 13%. En ambas generaciones los machos fueron significativamente más pesados que las hembras. Se encontraron notables diferencias entre generaciones para peso y talla, puesto que los selectos superaron al control en 27% y 8% (G1 y en 22% y 11% (G2 para el peso y la talla, respectivamente.In order to evaluate the effectiveness of mass selection by color and weight, two generations (G1 y G2 of red tilapia Oreochromis sp. were analyzed. 40000 larvae were used, at the sixth week fries with black spots and white were eliminated, and at week 14, the fishes were separated by sex. The weight (g, length, height and width (cm were measured in a sample of 150 individuals at 6, 14 and 24 weeks. At week 24, the best 150 males and 450 females with desirable colorations and higher weight were chosen. The selection was effective for coloration in G2, because proportion of red individuals increased in 15% compared to the control. The effect of the selection between generations (G1 y G2 was positive because proportion of red fries increased from 64% to 84%, and the spotted ones were reduced from 31% to 13%. In both generations males were significantly

  14. Caracterización de tilapia roja (Oreochromis sp. con marcadores moleculares RAPD Characterization of the red tilapia Oreochromis sp. through molecular markers RAPD

    Directory of Open Access Journals (Sweden)

    Julieta Torres Jaramillo

    2010-04-01

    Full Text Available Se utilizó la técnica RAPD (amplificación al azar de ADN polimórfico para el estudio de la diversidad genética de Oreochromis sp. (tilapia roja en cinco piscícolas del Valle del Cauca (Colombia y en la determinación del nivel de introgresión de las especies parentales Oreochromis mosambicus, O. niloticus y O. aureus. Se evaluaron 25 cebadores, ocho fueron polimórficos y se obtuvieron 109 bandas. Los valores de heterocigosidad esperada (0.196 a 0.256 y la estructura genética (Gst = 0.22 para Oreochromis sp. indicaron un elevado grado de polimorfismo y alta estructuración genética. Estos resultados fueron consistente con el Fst = 0.268 (P Random amplified polymorphic DNA (RAPD markers were used to study genetic diversity on red Tilapia (Oreochromis sp. species collected from five fish farms located in the Valle del Cauca, Colombia and to determine the level of introgression from three parental species O. mosambicus, O. niloticus and O. aureus into local Oreochromis populations. from the 25 RAPD primers evaluated, eight were polymorphic and 109 banding patterns were observed, any of them were specific. The expected levels of heterozygosis (0.1964 to 0.2561 and genetic structure (Gst = 0.22 funded for Oreochrosmis sp. indicate high grade of polymorphism and genetic structuring. This results were observed following the analysis of molecular variance [AMOVA] (Fst = 0.268 (P <0.0001 and Multiple correspondence analysis (Gst = 0.040. The values of genetic similarity, the analysis of group, the analysis of multiple correspondence and the level of introgression, indicated that the differences in the introgression levels(P=0.0001 were significant. The low level of observed genetic differentiation among populations, could be the result of fish with the same genetic origin, whereas the high variation within populations can be displayed by handling practices and the pressure of selection to favor commercial phenotypes. The level of introgression

  15. Prebiotic (Mannanoligosaccharide- MOS in fish nutrition: effects on nile-tilapia Oreochromis niloticus performance

    Directory of Open Access Journals (Sweden)

    Flávio Endrigo Cechim

    2012-12-01

    Full Text Available World fish production are growing about 10% a year and Brazil presents potential to be the first one in fish production until 2030. However, intensification of aquaculture production systems expose fish to numerous stressors such as poor water quality, crowding, handling and transport which may negatively affect their growth and and limit profitability of aquaculture systems. This current setup favors the use of dietary prebiotics for management of farmed fish as environmentally friendly practice. This study was set out to determine de effects of increasing levels of mannanoligosccharides (MOS on growth of juvenile Nile tilapia (Oreochromis niloticus. Fish (12.62 ± 0.38 were randomly distributed into 16 cages (0.25m3 polyvinyl chloride; 20 fish per cage, inside four 5m3 net-cage at Salto Caxias Hydroeletric water reservoir (Boa Vista da Aparecida, PR. Fish were fed during 60 days with a commercial diet (32%CP supplemented with 0.0 (control; 0.2; 0.4 and 0.8% dietary MOS (n=4. Water quality parameters (temperature, pH and dissolved oxygen were monitored during trial. After 60 days feeding trial, fish were fasted for 24 hours and sedated for biometrical parameters to evaluate growth parameters. It was observed no influence (p>0.05 of MOS supplementation on Nile tilapia growth parameters (weight gain, feed conversion rate, specific growth rate as well as for hepatosomatic index. Fish fed 0.4% dietary MOS showed increased (p<0.05 feed consumption (76.74 ± 3.98 when compared to fish fed control (unsupplemented diet (69.31 ± 1.11. MOS are indigestible glucomannoproteins, which provide mannose substrate upon which pathogenic gut bacteria selectively attach and prevents formation of mixed colonies leading to better gut health by increasing regularity, height and integrity of the gut villi and consequent better utilization and absorption of nutrients. Several authors found positive effects of MOS supplementation on fish growth and at same time, others

  16. Dietary levels of Mannanoligosaccharide (MOS for nile-tilapia (Oreochromis niloticus: Intestinal Morphology

    Directory of Open Access Journals (Sweden)

    Flavio Endrigo Cechim

    2012-12-01

    Full Text Available Intensification of aquaculture production systems exposes fish to numerous stressors, which may negatively affect their growth and limit profitability of aquaculture systems. In addition, fish farmers are now obliged to conform to Best Management Practices (BPMs regulations. This current setup favors the use of dietary prebiotics for management of farmed fish as environmentally friendly practice. Mannanoligosaccharides (MOS are complex carbohydrates derived from yeast (Saccharomyces cerevisiae cell walls. This study was set out to evaluate the effects of increasing levels of dietary MOS on intestinal morphology of Nile-tilapia. Fish (12.62 ± 0.38 were randomly distributed into 16 cages (0.25m3 polyvinyl chloride; 20 fish per cage, inside four 5m3 net-cage at Salto Caxias Hydroeletric water reservoir (Boa Vista da Aparecida, PR and fed diets containing increasing levels of MOS (0.0; 0.2; 0.4 and 0.8% during 30 days (n=4. The proximal intestine fragment of two specimens from each replicate was taken for histological observations. The histological sections (5 μm were stained with haematoxylin and eosin (H & E and documented photographically with a digital camera (DCM 130E digital camera for microscope 1.3 pixels, CMOS chip Software Scopephoto connected to a light microscope (EDUTEC 502 AC. The images were analyzed by using (BEL Eurisko software for intestinal villi measures. Water quality parameters (temperature, pH and dissolved oxygen were monitored during trial. It was observed influence (p<0.05 of MOS supplementation on Nile tilapia intestinal morphology. Fish fed diet containing 0.4% MOS supplementation showed increased (p<0.05 villi height (436.98±66.81 μm when compared to fish fed unsupplemented control diet (401.01±70.73 μm, 0.2% (364.59±61.68 μm and 0.8% (404.08±61.62 μm. Mannanoligosaccharides (MOS are complex carbohydrates derived from yeast (Saccharomyces cerevisiae cell walls and present mannose as primary carbohydrate

  17. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    Science.gov (United States)

    2012-01-01

    Background The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC end sequences and ESTs, but comparative genome analysis and maps of quantitative trait loci (QTL) are still limited. Results We have constructed a high-resolution radiation hybrid (RH) panel for the Nile tilapia and genotyped 1358 markers consisting of 850 genes, 82 markers corresponding to BAC end sequences, 154 microsatellites and 272 single nucleotide polymorphisms (SNPs). From these, 1296 markers could be associated in 81 RH groups, while 62 were not linked. The total size of the RH map is 34,084 cR3500 and 937,310 kb. It covers 88% of the entire genome with an estimated inter-marker distance of 742 Kb. Mapping of microsatellites enabled integration to the genetic map. We have merged LG8 and LG24 into a single linkage group, and confirmed that LG16-LG21 are also merged. The orientation and association of RH groups to each chromosome and LG was confirmed by chromosomal in situ hybridizations (FISH) of 55 BACs. Fifty RH groups were localized on the 22 chromosomes while 31 remained small orphan groups. Synteny relationships were determined between Nile tilapia, stickleback, medaka and pufferfish. Conclusion The RH map and associated FISH map provide a valuable gene-ordered resource for gene mapping and QTL studies. All genetic linkage groups with their corresponding RH groups now have a corresponding chromosome which can be identified in the karyotype. Placement of conserved segments indicated that multiple inter-chromosomal rearrangements have occurred between Nile tilapia

  18. Effects of dietary Lactobacillus plantarum and AHL lactonase on the control of Aeromonas hydrophila infection in tilapia.

    Science.gov (United States)

    Liu, Wenshu; Ran, Chao; Liu, Zhi; Gao, Qian; Xu, Shude; Ringø, Einar; Myklebust, Reidar; Gu, Zemao; Zhou, Zhigang

    2016-08-01

    This study addressed the effects of dietary Lactobacillus plantarum or/and N-acylated homoserine lactonase (AHL lactonase) on controlling Aeromonas  hydrophila infection in juvenile hybrid tilapia (Oreochromis niloticus♀ × O. aureus ♂). Fish were fed Lb. plantarum subsp. plantarum strain JCM1149 (10(8)  CFU/g feed) or/and AHL lactonase AIO6 (4 U/g) and were exposed to a chronic challenge of A. hydrophila NJ-1 (10(5)  cells/mL) for 14 days. Intestinal (foregut) alkaline phosphatase (IAP) activities were evaluated 1 day post challenge to reflect the resistance of fish against A. hydrophila infection. Parallel groups of fish with the same dietary assignments while unchallenged were also included to investigate the effect of dietary Lb. plantarum or/and AIO6 supplementation on gut health of tilapia. The results showed that IAP activity was significantly lower in fish fed with diets supplemented with Lb. plantarum JCM1149 or the combination of Lb. plantarum JCM1149 and AIO6, indicating enhanced resistance against A. hydrophila. Light microscopy and transmission electron microscopy images of foregut revealed damage caused by A. hydrophila NJ-1, but dietary Lb. plantarumJCM1149 or/and AIO6 significantly alleviated the damages. Compared to the fish immersed in A. hydrophila NJ-1, dietary Lb. plantarum JCM1149 or AIO6 could maintain the microvilli length in the foregut of tilapia. However, among the unchallenged groups of fish, the microvilli length in the foregut of tilapia fed AIO6 (singly or combination) and the microvilli density of tilapia fed AIO6 (singly) were significantly lower than those of the control, though the microvilli density in the combination treatment was significantly improved. Additionally, the dietary Lb. plantarum JCM1149 could down-regulate the expression of stress-related gene in the gut after the acute phase. In conclusion, the dietary Lb. plantarum JCM1149 is recommended to control the A. hydrophila infection in

  19. Molecular serotyping, virulence gene profiling and pathogenicity of Streptococcus agalactiae isolated from tilapia farms in Thailand by multiplex PCR.

    Science.gov (United States)

    Kannika, K; Pisuttharachai, D; Srisapoome, P; Wongtavatchai, J; Kondo, H; Hirono, I; Unajak, S; Areechon, N

    2017-06-01

    This study aimed to biotype Streptococcus agalactiae isolated from tilapia farms in Thailand based on molecular biotyping methods and to determine the correlation between the serotype and virulence of bacteria. In addition to a biotyping (serotyping) technique based on multiplex PCR of cps genes, in this study, we developed multiplex PCR typing of Group B streptococcus (GBS) virulence genes to examine three clusters of virulence genes and their correlation with the pathogenicity of S. agalactiae. The epidemiology of S. agalactiae in Thailand was analysed to provide bacterial genetic information towards a future rational vaccine strategy for tilapia culture systems. Streptococcus agalactiae were isolated from diseased tilapia from different areas of Thailand. A total of 124 S. agalactiae isolates were identified by phenotypic analysis and confirmed by 16S rRNA PCR. Bacterial genotyping was conducted based on (i) molecular serotyping of the capsular polysaccharide (cps) gene cluster and (ii) virulence gene profiling using multiplex PCR analysis of 14 virulence genes (lmb, scpB, pavA, cspA, spb1, cyl, bca, rib, fbsA, fbsB, cfb, hylB, bac and pbp1A/ponA). Only serotypes Ia and III were found in this study; serotype Ia lacks the lmb, scpB and spb1 genes, whereas serotype III lacks only the bac gene. Virulence tests in juvenile Nile tilapia demonstrated a correlation between the pathogenicity of the bacteria and their virulence gene profile, with serotype III showing higher virulence than serotype Ia. Epidemiological analysis showed an almost equal distribution in all regions of Thailand, except serotype III was found predominantly in the southern areas. Only two serotypes of S. agalactiae were isolated from diseased tilapia in Thailand. Serotype Ia showed fewer virulence genes and lower virulence than serotype III. Both serotypes showed a similar distribution throughout Thailand. We identified two major serotypes of S. agalactiae isolates associated with the outbreak in

  20. The influence of ration size on energetics and nitrogen retention in tilapia (Oreochromis niloticus)

    DEFF Research Database (Denmark)

    Skov, Peter Vilhelm; Duodu, Collins Prah; Adjei-Boateng, Daniel

    2017-01-01

    with ration size, feed conversion and protein retention were most efficient at ration sizes of 3%. Although the magnitude of the SDA response following feeding also increased with ration size, this was not proportionate to meal size. Therefore the metabolic cost of meal processing (SDA coefficient) was found......Proper nutrient management is essential for the environmental sustainability of aquaculture. While increasing daily rations generally may lead to improved growth rates, this does not necessarily mean that nutrients are utilized more efficiently. To investigate how ration size affects partitioning...... of dietary nutrient intake, the effects of meal size on growth and metabolism were examined in triplicate groups of adult Nile tilapia (Oreochromis niloticus) receiving daily rations corresponding to 1, 2, 3, or 4% of their biomass. While biomass gain and specific growth rates were positively correlated...

  1. DNA barcode for genetic traceability of Nile Perch and Nile Tilapia

    International Nuclear Information System (INIS)

    Avossa, Valeria

    2017-01-01

    For this study, mitochondrial DNA was extracted from 55 fish samples (26 Nile Perch Samples and 29 Nile Tilapia Samples collected from 3 different Ugandan regions of Lake Victoria. In order to optimize the PCR method, we also extracted DNA from two other different fish samples: one from Italy and one from a Viennese market. The COI gene was amplified using universal primers (COI2, COI3, cocktails of 8 and 4 primers respectively). After the amplification step, the amplicons were analysed using gel electrophoresis , in order to establish that the set primers worked well in the samples. The positive results of an agarose gel electrophoresis analysis with the PCR amplicons (amplicons length ~700pb) are shown.

  2. Incorporation and profile of fatty acids in tilapia fillets (Oreochromis niloticus fed with tung oil

    Directory of Open Access Journals (Sweden)

    Elton Guntendorfer Bonafé

    2013-02-01

    Full Text Available The acceptance of tung oil enriched diet and the incorporation of conjugated linolenic acid - CLnA into fillets of Genetically Improved Farmed Tilapia (GIFT were investigated. The diet was well accepted, and after 10 days CLnA was incorporated into the fillets with a 1.02% content of total fatty acids (FA. In addition, biosynthesis of the conjugated linoleic acid isomers - CLA (0.31% of fillet total FA content from CLnA, and the presence of alpha-linolenic acid - LNA (1.08% of fillet total FA content, eicosapentaenoic acid - EPA (2.85% of fillet total FA content and docosahexaenoic acid - DHA (3.08% of fillet total FA content were observed. Therefore, the consumption of this fish can increase the intake of different FA (CLnA, CLA, LNA, EPA and DHA, which play an important role in human metabolism.

  3. Effect of radiation on the early period of gametogenesis in Tilapia mossambika Peters

    International Nuclear Information System (INIS)

    Chmilevskij, D.A.; Ivojlov, A.A.

    1978-01-01

    Tilapia mossambica Peters larvae 10 days after hatching were X-irradiated at 350 R, and the number of germinative cells at different stages of development was followed. In the control, 10-day larvae possessed primordial germ cells and gonia; 15-day larvae had mostly gonia; in 20-day larvae some gonia were entering early prophase of meiosis; 25-day larvae possessed gonia and early meiotic prophase oocytes; and 30-day larvae had oogonia, oocytes at early prophase and at the previtellogenesis stage. After the irradiation, 13- and 14-day larvae showed some mitotic disturbances; however the mass death of germ cells was observed after their entering the pachytene stage in fishes 25 days old

  4. The utilization of Vallisneria aethiopica, Brassica oleracea and Pennisetum clandestinum by Tilapia rendalli

    Science.gov (United States)

    Hlophe, S. N.; Moyo, N. A. G.

    A common lawn grass; kikuyu grass, an abundant vegetable; cabbage and vallisneria a common macrophyte were tested for utilisation by two size classes of a herbivorous fish, Tilapia rendalli held in glass aquarium tanks. The test feeds were given to sub-adult T. rendalli for 133 days at 8% body weight and juvenile fish for 84 days at 15% body weight. Sub-adult and juvenile fish fed kikuyu grass attained a higher specific growth rate, higher protein efficiency ratio and better food conversion ratio than those fed cabbage and vallisneria. This is explained by the differences in the protein content, higher levels of lysine and the sulphur-containing amino acid, methionine in kikuyu grass. Palatability studies of the juveniles also showed that kikuyu was most preferred. However, sub-adults preferred vallisneria, kikuyu and cabbage respectively. The possible reasons for the selection are discussed.

  5. Mechanical and thermal properties of irradiated films based on Tilapia (Oreochromis niloticus) proteins

    Energy Technology Data Exchange (ETDEWEB)

    Sabato, S.F. [Radiation Technology Center, IPEN-CNEN/SP, Av. Lineu Prestes 2242, 05508 900 Sao Paulo, SP (Brazil)], E-mail: sfsabato@ipen.br; Nakamurakare, N.; Sobral, P.J.A. [Food Engineering Department, ZEA/FZEA/USP, Av. Duque de Caxias Norte 225, 13635 900 Pirassununga, SP (Brazil)

    2007-11-15

    Proteins are considered potential material in natural films as alternative to traditional packaging. When gamma radiation is applied to protein film forming solution it resulted in an improvement in mechanical properties of whey protein films. The objective of this work was the characterization of mechanical and thermal properties of irradiated films based on muscle proteins from Nile Tilapia (Oreochromis niloticus). The films were prepared according to a casting technique with two levels of plasticizer: 25% and 45% glycerol and irradiated in electron accelerator type Radiation Dynamics, 0.550 MeV at dose range from 0 to 200 kGy. Thermal properties and mechanical properties were determined using a differential scanning calorimeter and a texture analyzer, respectively. Radiation from electron beam caused a slightly increase on its tensile strength characteristic at 100 kGy, while elongation value at this dose had no reduction.

  6. Amino acid and protein changes in tilapia and spanish mackerel after irradiation and storage

    Energy Technology Data Exchange (ETDEWEB)

    Al-Kahtani, Hassan A.; Abu-Tarboush, Hamza M.; Atia, Mohamed; Bajaber, Adnan S.; Ahmed, Mohamed A.; El-Mojaddidi, Mohamed A

    1998-01-01

    Some amino acids in tilapia decreased while some others increased when subjected to doses up to 10.0 kGy. However, 10 kGy contributed to a significant reduction in all amino acids of Spanish mackerel. Variations in amino acid contents continued during post-irradiation storage with no consistent trend of increase or decrease. SDS-PAGE of protein from both fish showed 27 bands of subunits with MW < 14.0-94.0 KD. Isoelectric focusing patterns of sarcoplasmic protein of unirradiated and irradiated fish showed no charge in the number of bands, while some changes were observed in the intensities of the anodic and cathodic bands depending on isoelectric points (pIs)

  7. Oxygen Consumption of Tilapia and Preliminary Mass Flows through a Prototype Closed Aquaculture System

    Science.gov (United States)

    Muller, Matthew S.; Bauer, Clarence F.

    1994-01-01

    Performance of NASA's prototype CELSS Breadboard Project Closed Aquaculture System was evaluated by estimating gas exchange quantification and preliminary carbon and nitrogen balances. The total system oxygen consumption rate was 535 mg/hr kg/fish (cv = 30%) when stocked with Tilapia aurea populations (fresh weights of 97 +/- 19 to 147 +/- 36 g/fish for various trials). Oxygen consumption by T. aurea (260 mg/hr kg/fish) contributed to approximately one-half of total system demand. Continuous carbon dioxide quantification methods were analyzed using the,relation of carbon dioxide to oxygen consumption. Overall food conversion rates averaged 18.2 +/- 3.2%. Major pathways for nitrogen and carbon in the system were described with preliminary mass closure of 60-80% and 60% for nitrogen and carbon.

  8. Mechanical and thermal properties of irradiated films based on Tilapia (Oreochromis niloticus) proteins

    International Nuclear Information System (INIS)

    Sabato, S.F.; Nakamurakare, N.; Sobral, P.J.A.

    2007-01-01

    Proteins are considered potential material in natural films as alternative to traditional packaging. When gamma radiation is applied to protein film forming solution it resulted in an improvement in mechanical properties of whey protein films. The objective of this work was the characterization of mechanical and thermal properties of irradiated films based on muscle proteins from Nile Tilapia (Oreochromis niloticus). The films were prepared according to a casting technique with two levels of plasticizer: 25% and 45% glycerol and irradiated in electron accelerator type Radiation Dynamics, 0.550 MeV at dose range from 0 to 200 kGy. Thermal properties and mechanical properties were determined using a differential scanning calorimeter and a texture analyzer, respectively. Radiation from electron beam caused a slightly increase on its tensile strength characteristic at 100 kGy, while elongation value at this dose had no reduction

  9. Organochlorine Pesticides (OCs) and Polychlorinated Biphenyls (PCBs) in Tilapia zillii from Lake El-Manzala, Egypt

    International Nuclear Information System (INIS)

    El-Greisy, Zeinab Abdalbagi; Abdallah, A. Mohamed Ali

    2005-01-01

    A fresh water fish species, (Tilapia zillii) from Lake El-Manzala was analyzed for concentrations of several Organochlorine pesticides (OCs) and Polychlorine piphenyl's (PCBs) in liver, gonads, mesenteric fat, flesh and the digestive tract in mature fish during the breeding season. Polychlorinated piphenyls (PCBs) and Organochloripe pesticides (OCs) were calculated in (ng/g) dry weight (dw) in homogenized samples. The obtained results revealed differences in lipid content between these different organs. The females showed higher lipid content than males. There was significant positive correlation the lipid content and organochlorines and polychlorinated biphenyls (PCBs). The results come concomitant with the lipophilicity of studied compounds. However, the recoded concentration of these studied pollutants still does not exceed international hazardous levels. (author)

  10. Dried duckweed and commercial feed promote adequate growth performance of tilapia fi ngerlings

    OpenAIRE

    Tavares, Flávia de A.; Rodrigues, João Bosco R.; Fracalossi, Débora Machado; Esquivel, Juan; Roubach, Rodrigo

    2008-01-01

    http://dx.doi.org/10.5007/2175-7925.2008v21n3p91Desempenho de alevinos de tilapia nilótica alimentados com uma  combinação de lemnas secas e ração comercial. O presente estudo  avaliou a utilização de ração comercial e lemna seca no cultivo de  alevinos de tilápias nilóticas com o objetivo de reduzir os custos de produção. Três dietas representadas por lemna seca, ração comercial  (40% proteína bruta) e uma combinação de lemna seca e ração  comercial foram fornecidas a um grupo de 20 alevinos...

  11. Control of Ectoparasitic Monogenean Infestation on GIFT Tilapia (Oreochromis sp. using Salt Addition

    Directory of Open Access Journals (Sweden)

    Yani Hadiroseyani

    2009-07-01

    Full Text Available Ectoparasitic monogenean infestation is one of fish diseases which may cause mass mortality, therefore controlling the parasites is one of the important factors to ensure the success of aquaculture activities. Salt addition is one of disease curative and controlling techniques which is cheap, easy and environmental friendly as well as effective to control ectoparasites in freshwater environment. The objectives of this study were to examine monogenean parasites species in GIFT (Genetically Improved Farmed Tilapia tilapia, their tolerance to salt concentration and the most effective salt concentration to control the parasites. Identification, intensity and prevalence of parasitic monogenean were carried out on the external parts (body surface, fins and gills of 31 fishes. Subsequently, two different experiments were carried out  to determine parasites and fish resistance on various salt concentration at a range of 0 - 24 g/l with an interval of 2 g/l. To confirm the results of previous experiment, parasites infected fish was immersed in salt water at various concentration based on previous experiments. Two genera of monogenean were identified in GIFT tilapia, i.e. Gyrodactylus sp. on body surface and fins, and Cichlidogyrus sp. on gills with the same prevalence (100%. The intensity of those parasites was different, namely 27.84 ind/fish for Gyrodactylus sp. and 6.06 ind/fish for Cichlidogyrus sp. The intensity of both parasites was found to be lower as salt concentration increase. Salt concentration of 24 g/l was the most effective concentration to reduce parasites infestation and could totally treat the infested fish within 6 days. Keyword : tilapia, Oreochromis, monogenea, parasite and salt     ABSTRAK Serangan monogenea ektoparasitik merupakan salah satu masalah penyakit ikan yang dapat menyebabkan kematian masal, sehingga pengendaliannya merupakan salah satu kunci keberhasilan dalam usaha budidaya. Garam merupakan agen penyembuh atau

  12. The effect of titanium dioxide nanoparticles on antioxidant gene expression in tilapia ( Oreochromis niloticus)

    Science.gov (United States)

    Varela-Valencia, Ruth; Gómez-Ortiz, Nikte; Oskam, Gerko; de Coss, Romeo; Rubio-Piña, Jorge; del Río-García, Marcela; Albores-Medina, Arnulfo; Zapata-Perez, Omar

    2014-04-01

    The reactivity of nanoparticles (NPs) in biological systems is well recognized, but there are huge gaps in our understanding of NP toxicity in fish, despite a number of recent ecotoxicity studies. Therefore, the aim of this research was to evaluate the effect of titanium dioxide NPs (TiO2-NPs) on antioxidant gene expression in the tilapia, Oreochromis niloticus. First, different sizes, shapes, and phases of TiO2-NPs were synthesized and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS). Fish were injected intraperitoneally with different concentrations (0.1, 1.0, 10.0 mg/L), sizes (7, 14, and 21 nm), and phases (anatase and rutile) of TiO2-NPs, and sacrificed 3, 6, 12, and 24 h after injection, when their livers were removed. Total RNA was extracted, and expression of the catalase ( CAT), glutathione- S-transferase ( GST), and superoxide dismutase ( SOD) genes was assessed by real-time polymerase chain reaction (RT-PCR). The results showed that injection of 1.0 mg/L TiO2-NPs induced an initial mild increase in CAT, GST, and SOD gene expression in tilapia, after which transcript levels decreased. Fish injected with 7 and 14 nm TiO2-NPs showed an increase in antioxidant transcript levels 6 h after treatment. Finally, the rutile form generated stronger induction of the GST gene than anatase TiO2-NPs during the first 6 h after injection, which suggests that exposure to rutile causes higher levels of reactive oxygen species to be produced.

  13. Pharmaceutical significance of Leuconostoc mesenteroides KS-TN11 isolated from Nile Tilapia, Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Bilal Ahmad Paray

    2018-05-01

    Full Text Available Aquatic animals are known for their myriad of beneficial bacteria with diverse biologically active compounds. The current study was aimed to isolate and characterize potentially beneficial lactic acid bacteria from Nile Tilapia and evaluate their pharmaceutical applications. The fish samples were dissected and stomach, intestine, and gills were collected and serially diluted for the isolation of lactic acid bacteria (LAB on BCP agar media. Identification of isolate was carried by biochemical and molecular characterization using API kit and 16S rRNA gene sequencing analysis, respectively. Further, KS-TN11 was assessed for α-glucosidase inhibitory potential using the chromogenic method. A lactic acid bacterium KS-TN11 was isolated from the stomach of Nile Tilapia and identified as Leuconostoc mesenteroides. Effect of KS-TN11 on lipid accumulation in adipocytes was done by using Oil Red O staining. The isolate showed strong antibacterial activity against a number of pathogenic bacteria in vitro. In addition, L. mesenteroides KS-TN11 KS-TN11 (50 mg/ml and 100 mg/ml tends to inhibit adipogenesis in 3T3-L1 adipocytes and thus may have possible anti-obesity effects. Moreover, L. mesenteroides KS-TN11 exhibited substantial α–glucosidase inhibitory activities by 41.33% at 50 mg/ml and 64% at 100 mg/ml, respectively. The bacterium showed potent antibacterial activity against a number of pathogenic bacteria; in addition to alpha-glucosidase activity, and inhibition of lipid accumulation in 3T3-L1 cell line. These results reinforce KS-TN11 as a novel bacterium with an impending pharmaceutical application. Keywords: Lactic acid bacteria, Antimicrobial, Fish microflora, Anti-diabetic

  14. Genetic diversity of six populations of red hybrid tilapia, using microsatellites genetic markers

    Directory of Open Access Journals (Sweden)

    Boris Briñez R.

    2011-05-01

    Full Text Available Objective. To determine and evaluate the genetic diversity of six populations of red hybrid tilapia, with the purpose to assess the potential benefit of a future breeding program conducted at the Research Center for Aquaculture (Ceniacua, Colombia. Material and methods. A total of 300 individuals, representing a wide genetic variability, were genotyped using a fluorescent microsatellite marker set of 5 gene-based SSRs in 6 different farms belonging to 4 States of Colombia. Results. The result showed that the mean number of alleles per locus per population was 8.367. The population 5 had the highest mean number of alleles with 9.6 alleles, followed by population 4 with 9.4 alleles, population 2 with 9.2, population 3 with 8.0, population 1 with 7.2 and population 6 with 6.8 alleles. The analysis of the distribution of genetic variation was (17.32% among population, while among individuals within populations was (28.55% and within individuals was high (54.12%. The standard diversity indices showed that population 4 was the more variable (mean He=0.837 followed by population 1 (mean He=0.728, population 3 (mean He=0.721, population 5 (mean He=0.705, population 2 (mean He=0.690, population 6 (mean He=0.586. Highly significant deviations from Hardy–Weinberg, exhibited all of the populations, mostly due to deficits of heterozygotes. Genotype frequencies at loci UNH 106 of population 5 and loci UNH 172 of population 6 were Hardy-Weinberg equilibrium (HWE. Conclusions. The results of this study, contribute to the genetic breeding program of Tilapia, conduced by the Research Center for Aquaculture. The Fst distance showed that the samples are differentiated genetically and it is possible to use at the beginning of the genetic program. However, it is recommended to introduce others individuals to the crossbreeding program.

  15. Prevalence and Persistence of Listeria monocytogenes in Ready-to-Eat Tilapia Sashimi Processing Plants.

    Science.gov (United States)

    Chen, Bang-Yuan; Wang, Chung-Yi; Wang, Chia-Lan; Fan, Yang-Chi; Weng, I-Ting; Chou, Chung-Hsi

    2016-11-01

    A 2-year study was performed at two ready-to-eat tilapia sashimi processing plants (A and B) to identify possible routes of contamination with Listeria monocytogenes during processing. Samples were collected from the aquaculture environments, transportation tanks, processing plants, and final products. Seventy-nine L. monocytogenes isolates were found in the processing environments and final products; 3.96% (50 of 1,264 samples) and 3.86% (29 of 752 samples) of the samples from plants A and B, respectively, were positive for L. monocytogenes . No L. monocytogenes was detected in the aquaculture environments or transportation tanks. The predominant L. monocytogenes serotypes were 1/2b (55.70%) and 4b (37.97%); serotypes 3b and 4e were detected at much lower percentages. At both plants, most processing sections were contaminated with L. monocytogenes before the start of processing, which indicated that the cleaning and sanitizing methods did not achieve adequate pathogen removal. Eleven seropulsotypes were revealed by pulsed-field gel electrophoresis and serotyping. Analysis of seropulsotype distribution revealed that the contamination was disseminated by the processing work; the same seropulsotypes were repeatedly found along the work flow line and in the final products. Specific seropulsotypes were persistently found during different sampling periods, which suggests that the sanitation procedures or equipment used at these plants were inadequate. Plant staff should improve the sanitation procedures and equipment to reduce the risk of L. monocytogenes cross-contamination and ensure the safety of ready-to-eat tilapia products.

  16. Does MCH play a role on establishment or maintenance of social hierarchy in Nile tilapia?

    Science.gov (United States)

    Ramanzini, Guilherme Corrêa; Volpato, Gilson Luiz; Visconti, Maria Aparecida

    2018-01-01

    Body coloration has a fundamental role in animal communication by signaling sex, age, reproductive behavior, aggression, etc. Nile-tilapia exhibits dominance hierarchy and the dominants are paler than subordinates. During social interactions in these animals, these color changes occur rapidly, and normally the subordinates become dark. In teleosteans, from the great number of hormones and neurotransmitters involved in color changes, melanocyte hormone stimulates (α-MSH) and melanin concentrates hormone (MCH) are the most remarkable. The aim of this project was to investigate the role of MCH in the establishment of hierarchical dominance of the Nile-tilapia. We analyzed the effect of background coloration in the dominance hierarchy. It was then compared to the melanophore sensibility of dominants and subordinates' fishes to MCH; finally, it was checked if the social rank affects the number of these pigment cells in dominants and subordinated fishes. Fishes which have a social hierarchy established and adjusted individually to the background exhibits paler body coloration when a visual contact was possible, independently of previous social rank and background color. Probably, even recognizing each other, fishes could be defending their new territory. Melanophores of the subordinate fishes were more sensible to MCH than dominants. It suggests that dominants fishes, which are paler than subordinates, could be under a chronic effect of MCH, which could be due a desensitization of melanophores to this hormone. The opposite effect seems to be occurring on subordinate fishes. It was not observed a significant change in the number of melanophores when the fishes were exposed to a prolonged period of agonistic interaction. It is possible that the exposure time for this interaction might not have been sufficient to have any change in the number of these cells of dominants and subordinate fishes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Hematology of Nile tilapia (Oreochromis niloticus subjected to anesthesia and anticoagulation protocols

    Directory of Open Access Journals (Sweden)

    Nadia Cristine Weinert

    2015-12-01

    Full Text Available Clinical hematology facilitates the diagnosis of disease and can act as a prognostic indicator of pathological conditions in fish. The aim of the present study was to evaluate hematological parameters of Nile tilapia (Oreochromis niloticus subjected to different anesthetics and anticoagulants. Thirty apparently healthy fishes (average weight of 473 ± 35. 50 g and mean total length of 29. 33 ± 0. 37 cm, were selected from the local commercial fish farm in the Lages municipality (Santa Catarina, Brazil. The animals were randomly divided into three groups of 10. In two groups, anesthesia was induced with eugenol (70 mg·L- 1 (EG and Benzocaine hydrochloride (100 mg·L-1 (BG, respectively. Anesthesia was not administered to fish of the third group (CG/control group. Blood samples were obtained by venipuncture of the caudal vessels and placed into microtubes containing sodium heparin or Na2EDTA for further analysis. The results were analyzed by Sigma Stat for Windows, the paired t-test for significant differences between anticoagulants of the same group, and analysis of variance followed by the Tukey test for comparison of means between groups (p ? 0. 05. Most of the observed changes in the erythrogram were significantly higher for the anticoagulant heparin and benzocaine group in comparison to the control group. However, the values obtained for the leukogram were significantly higher for all groups subjected to the Na2EDTA anticoagulant, suggesting that heparin may cause cell clumping. The results suggest that the anesthetics under investigation effectively minimizes the effects of stress caused by handling and invasive procedures, and that the anticoagulant heparin causes less hemolysis in comparison to Na2EDTA for Nile tilapia. Thus, the hematological variations attributed to different anesthetic protocols and/or different anticoagulants should be considered for the species Oreochromis niloticus.

  18. Application of Essential Oils from Galanga Rhizome in Edible Coating Carrageenan as Antibacterial on Tilapia Fishball

    Directory of Open Access Journals (Sweden)

    Fajar Bayu Senoaji

    2017-08-01

    Full Text Available Fish ball is a perishable food product. One of an alternative method which could be applied to delay the deterioration process was using carrageenan edible coating with the addition of galangal rhizome’s essential oil as an antibacterial agent. The aim of this study was to find out whether the addition of carrageenan edible coating with galangal rhizome’s essential oil could increase the shelf life of the tilapia fish ball during cold storage or not. This study was used experimental laboratories with the completely randomized design used factorial (2x6 two factors include essential oils concentrations (0%, dan 1% and storage time (0, 3, 6, 9, 12, 15 with three repetitions. The shelf life of the fish ball observed by sensory, TPC, TVBN, pH, Aw, moisture content, and gel strength test. The parametric data were analyzed by the ANOVA, while the non-parametric was using the Kruskal Wallis test. As the result, the fish ball with the 1% treatment was still acceptable until 15 days of storage compared with the control which only lasts for 9 days. The other results were the sensory test was 6.63≤π≤6.95, TPC value was 1.07x105 cfu/g, TVBN value was 30.33±1.68 mgN%, the moisture content was 61.38%±0.47, the Aw was 0.89±0.006, the pH was 6.24±0.0, and the gel strength was 721.19±1.61 g.cm. The treatment of 1% essential oil addition to carrageenan edible coating was significantly different (p<0.05 compared to the control treatment during cold storage to the characteristic of tilapia fish ball.

  19. Molecular characterization of sdf1 and cxcr4 in the Mozambique tilapia, Oreochromis mossambicus.

    Science.gov (United States)

    Amat-Fernandez, Jorge; Hammond, Michael J; Liang, Di; Wang, Tianfang; Ventura, Tomer; Elizur, Abigail; Cummins, Scott F

    2017-01-01

    Animal sexual reproduction relies on primordial germ cells (PGCs), the predecessors of the germ cell lineage, giving rise to either spermatogonia or oogonia after the completion of gonadal differentiation. There is limited information on the mechanism of PGC migration leading to the formation of the primordial gonad in Perciform fish. Oreochromis mossambicus, a tilapiine species, was investigated that is a commercially important aquaculture species in many parts of the world while in other areas it has become an invasive pest. Key components involved in PGC migration were identified, including the stromal-cell derived factor 1 (Om-sdf1a, Om-sdf1b) and the CXC receptor 4 (Om-cxcr4): both share conservation with existing model species. The spatial gene expression profiles were determined through transcript and protein analysis and displayed distinct localisation within the region of the developing gonad in larvae and within the adult gonads of certain cell populations. A recombinant Om-sdf1a was produced in Escherichia coli that activates Om-cxcr4 using a BRET-based yeast in vitro assay system, suggesting that it is structurally similar to the native Om-sdf1a and is appropriate for further structural studies. This study has improved understanding of the molecular basis of tilapia reproduction through investigation of gonad development, which may be important in the progression towards reproductive suppression methods to control tilapia populations in the wild. In addition, this research will facilitate developments in germ cell transplantation, an innovative technique that harnesses germ cell migration and allows the uptake of foreign germ cells, which differentiate to produce sperm or ova. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Characterization of derived natural hydroxyapatite (HAp) obtained from different types of tilapia fish bones and scales

    Science.gov (United States)

    Fara, A. N. K. A.; Abdullah, H. Z.

    2015-07-01

    Hydroxyapatite, (HAp), Ca10(PO4)6(OH)2, is recognised as a biomaterial that is widely used for bone implant due to its chemical and structural similarity to the mineral components in human bone and enamel. The elements of HAp are primarily composed of calcium and phosphorus molar ratio of calcium to phosphorous is 1.67 capable to promote bone in-growth into prosthetic implant. Enormous amounts of by-product waste produced from fish factories generated an undesirable environmental impact. Thus, this study was conducted to obtain natural biological HAp from different types of tilapia fish bones and scales from fishery waste. Therefore, fish bones and scales can be as cheap source to produce biological HAp for medical applications. For this purpose, fish bones and scales of tilapia fish were boiled at 100°C to remove adhering meat and other impurities. Later, fish bones and scales were separated into several groups and subjected to different calcination temperatures of 800° C and 900° C for 3h respectively. Afterward, all calcined samples were crushed to form a fine powder. The XRD result revealed the presence of derived Hapfrom the samples powder and were identical with standard Hap. Thermo Gravimetric Analysis was carried out to show the thermal stability of the HAp powder from different types of fish bones and scales. SEM results show porous structure appeared in calcined samples compared to raw samples. The findings are the promising alternative to produce calcium and phosphorus from fishery wastes that beneficial to medical applications.

  1. Effects of irradiation and refrigeration on the nutrients and shelf-life of tilapia (Oreochromis niloticus)

    International Nuclear Information System (INIS)

    Siqueira, Alessandra Aparecida Zilio Cozzo de

    2001-01-01

    The objective of this study is to enhance the shelf-life of processed fish, combining ionizing radiation and refrigeration with minimal processing. The physical, chemical, nutritional and microbiological characteristics of the specie Tilapia nilotica (Oreochromis niloticus) were studied in eviscerated samples and in commercial cuts. The fish were separated into samples irradiated with 1.0, 2.2 and 5 kGy and non-irradiated samples. They were stored at temperatures ranging from 0.5 deg C to -2 deg C for 20 and 30 days. During storage, the level of moisture in the non-irradiated samples decreased and the levels of protein and lipid increased while the irradiated samples remained stable. The levels of pH, TVB-N and NPN increased in the non-irradiated samples but tended to remain stable in the irradiated fish samples. During storage, microbiological analyses for the presence of coliforms proved the efficiency of the irradiation process. The irradiated samples had a microbiological content below the levels established by the Brazilian seafood legislation, whereas the non-irradiated samples had a higher microbiological content and were not in conformity with the officially permitted levels. Salmonella spp. and Staphylococcus aureus were not detected. The levels of amino acids in muscles and fatty acids in oil remained stable in the irradiated fish stored samples but decreased in the non-irradiated ones. Lipid-oxidation, measured by the TBARS test, showed a tendency to increase when the dose of irradiation increased. The storage products after 30 days showed good acceptability for sensorial parameters, appearance, odour, color and texture, so it is possible to increase the shelf life of a minimally processed tilapia using combined irradiation and refrigeration. (author)

  2. Acute hypoxia stress induced abundant differential expression genes and alternative splicing events in heart of tilapia.

    Science.gov (United States)

    Xia, Jun Hong; Li, Hong Lian; Li, Bi Jun; Gu, Xiao Hui; Lin, Hao Ran

    2018-01-10

    Hypoxia is one of the critical environmental stressors for fish in aquatic environments. Although accumulating evidences indicate that gene expression is regulated by hypoxia stress in fish, how genes undergoing differential gene expression and/or alternative splicing (AS) in response to hypoxia stress in heart are not well understood. Using RNA-seq, we surveyed and detected 289 differential expressed genes (DEG) and 103 genes that undergo differential usage of exons and splice junctions events (DUES) in heart of a hypoxia tolerant fish, Nile tilapia, Oreochromis niloticus following 12h hypoxic treatment. The spatio-temporal expression analysis validated the significant association of differential exon usages in two randomly selected DUES genes (fam162a and ndrg2) in 5 tissues (heart, liver, brain, gill and spleen) sampled at three time points (6h, 12h, and 24h) under acute hypoxia treatment. Functional analysis significantly associated the differential expressed genes with the categories related to energy conservation, protein synthesis and immune response. Different enrichment categories were found between the DEG and DUES dataset. The Isomerase activity, Oxidoreductase activity, Glycolysis and Oxidative stress process were significantly enriched for the DEG gene dataset, but the Structural constituent of ribosome and Structural molecule activity, Ribosomal protein and RNA binding protein were significantly enriched only for the DUES genes. Our comparative transcriptomic analysis reveals abundant stress responsive genes and their differential regulation function in the heart tissues of Nile tilapia under acute hypoxia stress. Our findings will facilitate future investigation on transcriptome complexity and AS regulation during hypoxia stress in fish. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Performance of Nile tilapia juvenile fed diet containing different dosages ofrecombinant common carpgrowth hormone

    Directory of Open Access Journals (Sweden)

    Dian Hardiantho

    2013-11-01

    Full Text Available The studywas conductedtodetermine thedose of recombinant common carp growth hormone (rCcGH supplemented in the commercial diet that generates the best performanceonbodyweight, biomass, andfeed conversion rate of juvenile tilapia.The dose of rCcGH administered was10, 20, and30mg/kg of commercial feed, andnorGH supplementation as control. Eachtreatment was designed in triplicates. Juveniles at average bodylengthof about2cm(average body weight of 0.7 g were reared in a density of25fish/m2, for three weeks in hapa net at a size of 2×2×1 m3. Fish were fed diet containing rCcGH twicea week with an interval ofthreedays. The juvenile were fed with the rCcGH supplemented diet three times daily at satiation. The results showedthat average body weight andbiomass of fish treated by rCcGH with the doses of 20 and 30 mg/kg feed was higher (p<0.05 than that of 10 mg/kg and control. In addition, feed conversionrate of 20 and 30 mg/kg feed treatments was lower (p<0.05 than that of 10 mg/kg and control. RT-PCR analysisshowedthat expression level of IGF-1 gene in juvenile liver was increased in parallel with the increasing of rCcGH dosages supplemented in diet.This suggestedthatIGF-1 plays an important rolein the induction ofgrowth,andfeed conversionefficiencyof tilapiafed diet containing rCcGH. The bestperformance of juvenile can be obtainedby feeding with diet containingrCcGH20‒30mg/kgof feed. Keywords: rCcGH, IGF-I, recombinant growthhormone,performance, Nile tilapia.

  4. Dietary probiotic supplementation improves growth and the intestinal morphology of Nile tilapia.

    Science.gov (United States)

    Ramos, M A; Batista, S; Pires, M A; Silva, A P; Pereira, L F; Saavedra, M J; Ozório, R O A; Rema, P

    2017-08-01

    Probiotic administration can be a nutritional strategy to improve the immune response and growth performance of fish. The current study aimed to evaluate the effects of a probiotic blend (Bacillus sp., Pediococcus sp., Enterococcus sp., Lactobacillus sp.) as a dietary supplement on growth performance, feed utilization, innate immune and oxidative stress responses and intestinal morphology in juvenile Nile tilapia (Oreochromis niloticus). The probiotic was incorporated into a basal diet at three concentrations: 0 g/kg (A0: control), 3 g/kg (A1: 1.0×106 colony forming unit (CFU)/g) and 6 g/kg (A2: 2.3×106 CFU/g diet). After 8 weeks of probiotic feeding, weight and specific growth rate where significantly higher in fish-fed A1 diet than in fish-fed A0. Alternative complement in plasma was significantly enhanced in fish-fed A2 when compared with A0. The hepatic antioxidant indicators were not affected by probiotic supplementation. Villi height and goblet cell counts increased significantly in the intestine of fish-fed A1 and A2 diets compared with A0. The dietary probiotic supplementation was maintained until 20 weeks of feeding. Then the selected immune parameters, digestive enzymes and apparent digestibility of diets were studied. No effect of probiotic feeding was observed after that longer period supplementation. The dietary supplementation of mixed species probiotic may constitute a valuable nutritional approach towards a sustainable tilapia aquaculture. The improvement of the immune responses and intestinal morphology play an important role in increasing growth performance, nutrient absorption and disease resistance in fish, important outcomes in such a competitive and developing aquaculture sector.

  5. The use of nile tilapia ( Oreochromis niloticus) cultivation wastewater for the production of romaine lettuce ( Lactuca sativa L. var. longifolia) in water recirculation system

    Science.gov (United States)

    Effendi, Hefni; Wahyuningsih, Sri; Wardiatno, Yusli

    2017-10-01

    In the recirculation aquaponic system (RAS), fish farming waste was utilized as a nutrient for plant, minimizing the water need, reducing the waste disposal into the environment, and producing the fish and plant as well. The study aimed to examine the growth of romaine lettuce ( Lactuca sativa L. var. Longifolia) in aquaponic system without the addition of artificial nutrient. The nutrient relies solely on wastewater of nile tilapia ( Oreochromis niloticus) cultivation circulated continuously on the aquaponic system. The results showed that tilapia weight reached 48.49 ± 3.92 g of T3 (tilapia, romaine lettuce, and inoculated bacteria), followed by T2 (tilapia and romaine lettuce) and T1 (tilapia) of 47.80 ± 1.97 and 45.89 ± 1.10 g after 35 days of experiment. Tilapia best performance in terms of growth and production occurred at T3 of 3.96 ± 0.44 g/day, 12.10 ± 0.63 %/day, 96.11 ± 1.44 % and 1.60 ± 0.07 for GR, SGR, SR, and FCR, respectively. It is also indicated by better water quality characteristic in this treatment. Romaine lettuce harvests of T2 and T3 showed no significant difference, with the final weight of 61.87 ± 5.59 and 57.74 ± 4.35 g. Overall, the integration of tilapia fish farming and romaine lettuce is potentially a promising aquaponic system for sustainable fish and horticulture plant production.

  6. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation.

    Science.gov (United States)

    Kalujnaia, Svetlana; Hazon, Neil; Cramb, Gordon

    2016-08-01

    A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells. Copyright © 2016 the American Physiological Society.

  7. Prolactin is a major inhibitor of hepatic Leptin A synthesis and secretion: studies utilizing a homologous Leptin A ELISA in the tilapia.

    Science.gov (United States)

    Douros, Jonathan D; Baltzegar, David A; Breves, Jason P; Lerner, Darren T; Seale, Andre P; Gordon Grau, E; Borski, Russell J

    2014-10-01

    The present study identifies regulatory interactions between leptin A (LepA) and the pituitary hormone prolactin (PRL). In order to measure tilapia (Oreochromis mossambicus) LepA, an enzyme-linked immunosorbent assay (ELISA) utilizing a rabbit polyclonal antibody specific to tilapia LepA was first developed. The antibody shows strong cross reactivity to recombinant tilapia LepA (rtLepA), and a corresponding 16kDa protein in both tilapia and striped bass plasma, but not to recombinant human leptin (rhLep). The assay has a linear detection range of 0.25-1000nM, with intra- and interassay variability of 9% and 16%, respectively. Plasma LepA levels measured in tilapia ranged from 0.8 to 3.9nM, similar to that found for other vertebrates. Hypophysectomy (Hx) increased circulating LepA and lepa mRNA levels in the liver, the dominant source of hormone production. Adminstration of ovine PRL (oPRL, 5μg/g BW) to Hx fish restored circulating LepA and hepatic lepa mRNA levels to those of control fish. Additionally, oPRL reduced lepa mRNA levels in a dose-dependent fashion in cultured hepatocytes following an 18h incubation. Previous work in our lab indicates that rhLep stimulates PRL release in vitro from tilapia pituitaries. Here, both rtLepA and rhLep (0.5μg/g BW) increased mRNA expression of tilapia prolactin mRNAs (prl1, prl2) in the pituitary in vivo. These results demonstrate that LepA enhances pituitary prolactin synthesis and release, while PRL in turn inhibits hepatic leptin secretion and synthesis in teleosts. We postulate this regulatory interaction may be necessary for mobilizing energy reserves during acute hyperosmotic adaptation. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. La pisciculture de Tilapia nilotica (= Sarotherodon niloticus dans les eaux continentales de Côte d'Ivoire

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    Vincke, P.

    1985-01-01

    Full Text Available The fishculture of Tilapia niloiica (Sarotherodon niloticus in freshwater of Ivory Coast. In Ivory Coast, the freshwater fishculture in rural areas is mainly on a small scale. This type of breeding in ponds (2 to 4 ares yields on an average 3 metric tons of fish/ha/year and represents only an activity with self-consumption of products. The yield in intensive pond fishculture Tilapia nilotica is on an average 6 to 7 metric tons/ha/year but yields bigger than 10 metric tons/ha/year are not uncommon. The intensive fishculture in floating cages, requiring a minor investment but a more improved formation than in fischculture, yields on an average about 30 to 40 kg/m3/year. However the effective development of this activity rests on the resolution of problems like the sufficient fry production, the feeding and the commercialization.

  9. Anaerobic bio-digestion of concentrate obtained in the process of ultra filtration of effluents from tilapia processing unit

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    Milena Alves de Souza

    2012-02-01

    Full Text Available The objective of the present study was to evaluate the efficiency of the process of biodigestion of the protein concentrate resulting from the ultrafiltration of the effluent from a slaughterhouse freezer of Nile tilapia. Bench digesters were used with excrements and water (control in comparison with a mixture of cattle manure and effluent from the stages of filleting and bleeding of tilapias. The effluent obtained in the continuous process (bleeding + filleting was the one with highest accumulated population from the 37th day, as well as greatest daily production. Gases composition did not differ between the protein concentrates, but the gas obtained with the use of the effluent from the filleting stage presented highest methane gas average (78.05% in comparison with those obtained in the bleeding stage (69.95% and in the continuous process (70.02% or by the control method (68.59%.

  10. Apparent digestibility of nutrients, energy, and amino acid of nontoxic and detoxified physic nut cakes for Nile tilapia

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    Hamilton Hisano

    2015-09-01

    Full Text Available Abstract:The objective of this work was to evaluate the apparent digestibility coefficients of nutrients, energy, and amino acids of nontoxic and detoxified physic nut cakes treated with solvent plus posterior extrusion, for Nile tilapia. The apparent digestibility coefficients of crude protein and gross energy were higher for detoxified than for nontoxic physic nut cake. However, the apparent digestibility coefficient of ether extract of the nontoxic physic nut cake was higher than that of the detoxified one. The apparent digestibility coefficient of amino acids of both feed ingredients was superior to 80%, except for glycine, for the nontoxic psychic nut cake, and for threonine, for the detoxified one. Nontoxic and detoxified physic nut cakes show apparent digestibility coefficient values equivalent to those of the other evaluated oilseeds and potential for inclusion in Nile tilapia diets.

  11. Morphological and molecular characterization of a novel myxosporean parasite Myxobolus bejeranoi n. sp. (Cnidaria: Myxosporea) from hybrid tilapia in Israel.

    Science.gov (United States)

    Lövy, Alena; Smirnov, Margarita; Brekhman, Vera; Ofek, Tamir; Lotan, Tamar

    2018-02-01

    Myxosporean infections can cause severe damage to commercially grown tilapia. Here, we report a novel myxosporean that was found in gills of Oreochromis aureus male × Oreochromis niloticus female, which is an important aquaculture tilapia hybrid in Israel. Three-month-old fish were found to have cysts located in gill muscle tissue, which were filled with both immature and mature spores. Affected fish displayed higher mortality rate. Spore dimensions (10.8 ± 0.7 μm length × 6.8 ± 0.6 μm width) and molecular characterization using 18S ribosomal DNA revealed that the unknown parasite belongs in the Myxobolus clade. Based on the infection site, spore morphology and molecular characterization, we describe this parasite as Myxobolus bejeranoi n. sp. (MF401455). Phylogenetic analysis showed that the new species is most closely related to two Myxobolus spp. from O. niloticus in Egypt and Ghana.

  12. Prevalence of neurotoxic Clostridium botulinum type C in the gastrointestinal tracts of tilapia (Oreochromis mossambicus) in the Salton Sea.

    Science.gov (United States)

    Nol, P; Rocke, T E; Gross, K; Yuill, T M

    2004-07-01

    Tilapia (Oreochromis mossambicus) have been implicated as the source of type C toxin in avian botulism outbreaks in pelicans (Pelecanus erythrorhynchos, Pelecanus occidentalis californicus) at the Salton Sea in southern California (USA). We collected sick, dead, and healthy fish from various sites throughout the Sea during the summers of 1999 through 2001 and tested them for the presence of Clostridium botulinum type C cells by polymerase chain reaction targeting the C(1) neurotoxin gene. Four of 96 (4%), 57 of 664 (9%), and five of 355 (1%) tilapia tested were positive for C. botulinum type C toxin gene in 1999, 2000, and 2001, respectively. The total number of positive fish was significantly greater in 2000 than in 2001 (P<0.0001). No difference in numbers of positives was detected between sick and dead fish compared with live fish. In 2000, no significant relationships were revealed among the variables studied, such as location and date of collection.

  13. COMPARISON AND INTERACTION GENOTIPE-ENVIRONMENT OF THE PRODUCTIVE PERFORMANCE IN THREE GENETIC LINES OF TILAPIA Oreochromis sp.

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    Jorge Luis Pérez-Fuentes

    2016-05-01

    Full Text Available Tilapia is the second most widely cultivated species in the international scope, due to their fast growing and breeding capacity in captivity. Its biggest problem is the unpredictability of the productive performance of varieties in different environments and management types. For this reason, the productive performance of three lines: Oreochromis niloticus (N, red Oreochromis mossambicus (M and Rocky Mountain (R, cultured in five sites in two environments (Presses: Miguel de la Madrid and Miguel Aleman in the State of Oaxaca, Mexico was compared. Cages with dimensions between 18 and 48 m3 with stocking density of 7 to 28 fish m-3 were used. Feeding varied depending on the producers (1 to 3 portions a day/cage (300 to 1200 g of feed. Total length (TL, weight (P, survival (SUP and fillet yield (RF were evaluated in each genetic line. Results from physicochemical parameters of water, environments of culture and production efficiency of the strains indicated no significant differences, except for weight gain (g between sites of culture. However, it was considered that the differences were mainly due to handling during the culture, rather than the genetic line. Genetic lines showed similar performance (Tilapia R: LT 16.5 ± 3.1 cm, P 99.0± 46.6 g, 28 % RF, SUP 91.6 %. Tilapia N: LT 16.7 ± 3.7 cm, P 98.2 ± 40.9, RF 23 % SUP 86 %. Tilapia M: LT 15.4 ± 4.6 cm, P 100.1 ± 112.5 g, 30 % RF, SUP 91.6 %. Under the conditions evaluated, type of management could influence the efficiency of the culture more than the genetic line.

  14. Optimization of crude protein in diets for Nile tilapia reared in net pens: performance, hematology, and water quality

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    Débora Del Puppo

    Full Text Available ABSTRACT: Two experiments were conducted to evaluate the effects of reducing dietary crude protein (CP, based on the ideal protein concept for Nile tilapia reared in net pens. The experimental (isocaloric, isocalcium, and isophosphoric diets were formulated to contain 270, 300, 330, and 360g kg-1 CP. In experiment 1, 4320 Nile tilapia (13.5±0.82g were used to evaluate the performance and hematological parameters. The experimental design was completely randomized and the fish were distributed in 24 net pens (1.0m3, with four diets, six replicates, and 180 fishes per experimental unit. In experiment 2, 40 Nile tilapia (22.5±0.56g were used to evaluate the ammonia excretion. Fish were distributed in 40 aquaria (3.0L, with one fish per aquarium (n=10. No protein reduction effect was observed in feed intake and the hematocrit and hemoglobin values. Regarding the statistic models used in the present study, difference was observed between CP values. The optimal level estimated by the quadratic equation first interception with the linear response plateau (LRP as a response to CP changes in the diet was determined for weight gain (324.3g kg-1 and feed conversion (317.8g kg-1. After reduction in the CP levels, a linear reduction was observed in the ammonia excretion in water. Based on the ideal protein concept for Nile tilapia reared in net pens, reducing the CP levels in the diets is possible, without change in the performance and hematological parameters, and with a reduction in the levels of ammonia excretion in water, since amino acids are supplemented.

  15. Tissue distribution of perfluoroalkyl acids and health status in wild Mozambique tilapia (Oreochromis mossambicus) from Loskop Dam, Mpumalanga, South Africa

    Institute of Scientific and Technical Information of China (English)

    Jacqueline T.Bangma; Olivia Rynders; Joseph R.Sara; Willem J.Smit; John A.Bowden; Jessica L.Reiner; Hannes Botha; Theresa M.Cantu; Marco A.Gouws; Matthew P.Guillette; Jererny P.Koelmel; Wilmien J.Luus-Powell; Jan Myburgh

    2017-01-01

    This study examined concentrations of 15 perfiuoroalkyl acids (PFAAs) in tissues from male Mozambique dlapia (Oreochromis mossambicus) collected at Loskop Dam,Mpumalanga,South Africa in 2014 and 2016.Nine of the 15 PFAAs were detected frequently and were included in statistical analysis and included two of the most commonly known PFAAs,perfluorooctanesulfonic acid (PFOS) (median,41.6 ng/g) and perfluorooctanoic acid (PFOA) (median,0.0825 ng/g).Of the tissues measured,plasma (2016 and 2014 median,22.2 ng/g) contained the highest PFAA burden followed by (in descending order):liver (median,11.6 ng/g),kidney (median,9.04 ng/g),spleen (median,5.92 ng/g),adipose (median,2.54 ng/g),and muscle (median,1.11 ng/g).Loskop Dam tilapia have been affected by an inflammatory disease of the adipose tissue known as pansteatitis,so this study also aimed to investigate relationships between PFAA tissue concentrations and incidence of pansteatitis or fish health status.Results revealed that healthy tilapia exhibited an overall higher (p-value < 0.05) PFAA burden than pansteatitis-affected tilapia across all tissues.Further analysis showed that organs previously noted in the literature to contain the highest PFAA concentrations,such as kidney,liver,and plasma,were the organs driving the difference in PFAA burden between the two tilapia groups.Care must be taken in the interpretations we draw from not only the results of our study,but also other PFAA measurements made on populations (human and wildhfe ahke) under differing health status.

  16. Analysis of potential risks from the bacterial communities associated with air-contact surfaces from tilapia (Oreochromis niloticus) fish farming.

    Science.gov (United States)

    Grande Burgos, Maria Jose; Romero, Jose Luis; Pérez Pulido, Rubén; Cobo Molinos, Antonio; Gálvez, Antonio; Lucas, Rosario

    2018-01-01

    Tilapia farming is a promising growing sector in aquaculture. Yet, there are limited studies on microbiological risks associated to tilapia farms. The aim of the present study was to analyse the bacterial communities from solid surfaces in contact with air in a tilapia farm in order to evaluate the presence of bacteria potentially toxinogenic or pathogenic to humans or animals. Samples from a local tilapia farm (tank wall, aerator, water outlets, sink and floor) were analyzed by high throughput sequencing technology. Sequences were assigned to operational taxonomic units (OTUs). Proteobacteria was the main phylum represented in most samples (except for one). Cyanobacteria were a relevant phylum in the inner wall from the fattening tank and the wet floor by the pre-fattening tank. Bacteroidetes were the second phylum in relative abundance for samples from the larval rearing tank and the pre-fattening tank and one sample from the fattening tank. Fusobacteria showed highest relative abundances in samples from the larval rearing tank and pre-fattening tank. Other phyla (Verrucomicrobia, Actinobacteria, Firmicutes, Planktomycetes, Acidobacteria, Chloroflexi, Chlorobi, Gemmatiomonadetes or Fibrobacters) had lower relative abundances. A large fraction of the reads (ranging from 43.67% to 72.25%) were assigned to uncultured bacteria. Genus Acinetobacter (mainly A. calcoaceticus/baumanni) was the predominant OTU in the aerator of the fattening tank and also in the nearby sink on the floor. The genera Cetobacterium and Bacteroides showed highest relative abundances in the samples from the larval rearing tank and the pre-fattening tank. Genera including fish pathogens (Fusobacterium, Aeromonas) were only detected at low relative abundances. Potential human pathogens other than Acinetobacter were either not detected or had very low relative abundances (Acinetobacter and potential cyanotoxin-producing cyanobacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Effect of dietary genistein on growth performance, digestive enzyme activity, and body composition of Nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Chen, Dong; Wang, Wei; Ru, Shaoguo

    2015-01-01

    An 8-week feeding experiment was performed to evaluate the effect of dietary genistein on growth performance, body composition, and digestive enzymes activity of juvenile Nile tilapia ( Oreochromis niloticus). Four isonitrogenous and isoenergetic diets were formulated containing four graded supplements of genistein: 0, 30, 300, and 3 000 μg/g. Each diet was randomly assigned in triplicate to tanks stocked with 15 juvenile tilapia (10.47±1.24 g). The results show that 30 and 300 μg/g dietary genistein had no significant effect on growth performance of Nile tilapia, but the higher level of genistein (3 000 μg/g) significantly depressed the final body weight and specific growth rate. There was no significant difference in survival rate, feed intake, feed efficiency ratio or whole body composition among all dietary treatments. An assay of digestive enzymes showed that the diet containing 3 000 μg/ggenistein decreased stomach and hepatopancreas protease activity, and amylase activity in the liver and intestine, while a dietary level of 300 μg/g genistein depressed stomach protease and intestine amylase activities. However, no significant difference in stomach amylase activity was found among dietary treatments. Overall, the results of the present study indicate that a high level of dietary genistein (3 000 μg/g, or above) would significantly reduce the growth of Nile tilapia, partly because of its inhibitory effect on the activity of major digestive enzymes. Accordingly, the detrimental effects of genistein, as found in soybean products, should not be ignored when applied as an alternative ingredient source in aquaculture.

  18. Depletion study, withdrawal period calculation and bioaccumulation of sulfamethazine in tilapia (Oreochromis niloticus) treated with medicated feed.

    Science.gov (United States)

    Nunes, Kátia S D; Vallim, José H; Assalin, Márcia R; Queiroz, Sonia C N; Paraíba, Lourival C; Jonsson, Claudio M; Reyes, Felix G R

    2018-04-01

    The residue depletion of sulfamethazine (SMZ) was evaluated in tilapia (Oreochromis niloticus) after 11 days of administration of medicated feed containing SMZ, at the dose of 422 mg/kg body weight (bw). The determination of SMZ in feed and tilapia fillet was carried out using the QuEChERS approach for sample preparation, and high performance liquid chromatography with diode array detector (HPLC-DAD) and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) for quantitation, respectively. Both methods were validated based on international and Brazilian guidelines and shown to be suitable for the intended purposes. The withdrawal period to reach the maximum residue level (MRL) of 100 μg/kg, according to the European Union (EU) legislative framework to all substances belonging to the sulfonamide (SA) group (EU, 2010), was 10 days (260 °C-day). After treatment, the maximum level of SMZ accumulation in the tilapia muscle was 1.6 mg/kg. SMZ was shown to be quickly excreted by tilapia. Thus, considering the acceptable daily intake of SMZ established by the Codex Commission (0-0.05 mg/kg bw), and a factor of 5 times the upper amount of fish consumption in Brazil (38 kg/year), this study showed that there is a low risk of adverse effects to consumers. This study offers subsidies not only for the establishment of public policies with regard to the use of veterinary drugs currently not allowed in a country by their legal legislative framework for fish farming, but also to fish producers for the proper handling to ensure safe fish fillets. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Tissue distribution of perfluoroalkyl acids and health status in wild Mozambique tilapia (Oreochromis mossambicus) from Loskop Dam, Mpumalanga, South Africa.

    Science.gov (United States)

    Bangma, Jacqueline T; Reiner, Jessica L; Botha, Hannes; Cantu, Theresa M; Gouws, Marco A; Guillette, Matthew P; Koelmel, Jeremy P; Luus-Powell, Wilmien J; Myburgh, Jan; Rynders, Olivia; Sara, Joseph R; Smit, Willem J; Bowden, John A

    2017-11-01

    This study examined concentrations of 15 perfluoroalkyl acids (PFAAs) in tissues from male Mozambique tilapia (Oreochromis mossambicus) collected at Loskop Dam, Mpumalanga, South Africa in 2014 and 2016. Nine of the 15 PFAAs were detected frequently and were included in statistical analysis and included two of the most commonly known PFAAs, perfluorooctanesulfonic acid (PFOS) (median, 41.6ng/g) and perfluorooctanoic acid (PFOA) (median, 0.0825ng/g). Of the tissues measured, plasma (2016 and 2014 median, 22.2ng/g) contained the highest PFAA burden followed by (in descending order): liver (median, 11.6ng/g), kidney (median, 9.04ng/g), spleen (median, 5.92ng/g), adipose (median, 2.54ng/g), and muscle (median, 1.11ng/g). Loskop Dam tilapia have been affected by an inflammatory disease of the adipose tissue known as pansteatitis, so this study also aimed to investigate relationships between PFAA tissue concentrations and incidence of pansteatitis or fish health status. Results revealed that healthy tilapia exhibited an overall higher (p-valuetilapia across all tissues. Further analysis showed that organs previously noted in the literature to contain the highest PFAA concentrations, such as kidney, liver, and plasma, were the organs driving the difference in PFAA burden between the two tilapia groups. Care must be taken in the interpretations we draw from not only the results of our study, but also other PFAA measurements made on populations (human and wildlife alike) under differing health status. Copyright © 2017. Published by Elsevier B.V.

  20. Quality Evaluation Focusing on Tissue Fractal Dimension and Chemical Changes for Frozen Tilapia with Treatment by Tangerine Peel Extract

    Science.gov (United States)

    He, Qi; Yang, Zhao; Gong, Bin; Wang, Jingjing; Xiao, Kaijun; Yang, Shang-Tian

    2017-02-01

    This work aimed to establish an effective approach to evaluate the quality of frozen fish, focusing on changes in fish tissue structure and chemical composition during storage. Fresh tilapia samples were treated by coating with tangerine peel (TP) extract and then stored at -4, -8 and -18 °C, respectively, for 40 days. The frozen fish tissues were analyzed for structural and chemical changes. Fractal dimension, which quantifies the porous structure formed in the tissue samples, texture properties including hardness and springiness, and moisture content and water activity all decreased during the storage, while the extents of lipid oxidation, measured as peroxide value and thiobarbituric acid concentration, and protein degradation, monitored with total volatile basic nitrogen and trichloroacetic acid soluble peptides, increased. The change rates of these parameters decreased with decreasing the storage temperature and by applying TP extract. A model was developed for predicting fractal dimension, which indicated the quality of preserved tilapia and thus can be used to predict the shelf life under different storage temperatures. The results demonstrated that TP extract could extend the shelf life of frozen tilapia by 35-45% by inhibiting changes in tissue structure, moisture loss, lipid oxidation and protein degradation during frozen storage.

  1. Aprovechamiento de semillas de hule (Hevea brasiliensis L. para alimentación de tilapia (Oreochromis niloticus L.

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    Gustavo Adolfo Elías-Ogaldez

    2017-03-01

    Full Text Available Se elaboró un concentrado artesanal para tilapia (Oreochromis niloticus L. con la finalidad de contribuir al aprovechamiento de los subproductos del cultivo de hule (Hevea brasiliensis Müll. Arg y de reducir los costos de producción de la tilapia. La investigación fue tipo aplicada y experimental, realizándose en la zona costera del Pacifico guatemalteco. Se concluyó que la harina de semilla de hule es un insumo apropiado para sustituir parcial o totalmente la harina de semilla de soya, en la formulación de concentrados artesanales para tilapia. Todos los tratamientos donde se utilizó harina de semilla de hule presentaron una mejor supervivencia y FCA frente al testigo. El tratamiento T3 presentó la mejor tasa de retorno marginal frente al testigo y los demás tratamientos. Por último, se recomienda continuar la investigación tomando en cuenta que la semilla de hule es deficiente en aminoácidos esenciales, los cuales se pueden adicionar para mejorar su rendimiento nutricional.

  2. Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae) in the Aguamilpa Reservoir, Mexico.

    Science.gov (United States)

    Peña Messina, Emilio; Tapia Varela, Raul; Velázquez Abunader, José Iván; Orbe Mendoza, Alma Araceli; Velazco Arce, Javier Marcial de Jesús Ruiz

    2010-12-01

    Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species.

  3. Distribution and health risk assessment of trace metals in freshwater tilapia from three different aquaculture sites in Jelebu Region (Malaysia).

    Science.gov (United States)

    Low, Kah Hin; Zain, Sharifuddin Md; Abas, Mhd Radzi; Md Salleh, Kaharudin; Teo, Yin Yin

    2015-06-15

    The trace metal concentrations in edible muscle of red tilapia (Oreochromis spp.) sampled from a former tin mining pool, concrete tank and earthen pond in Jelebu were analysed with microwave assisted digestion-inductively coupled plasma-mass spectrometry. Results were compared with established legal limits and the daily ingestion exposures simulated using the Monte Carlo algorithm for potential health risks. Among the metals investigated, arsenic was found to be the key contaminant, which may have arisen from the use of formulated feeding pellets. Although the risks of toxicity associated with consumption of red tilapia from the sites investigated were found to be within the tolerable range, the preliminary probabilistic estimation of As cancer risk shows that the 95th percentile risk level surpassed the benchmark level of 10(-5). In general, the probabilistic health risks associated with ingestion of red tilapia can be ranked as follows: former tin mining pool > concrete tank > earthen pond. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

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    Pedro Luiz de CASTRO

    2016-01-01

    Full Text Available Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia.

  5. Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

    Directory of Open Access Journals (Sweden)

    Pedro Luiz de CASTRO

    Full Text Available Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia.

  6. Molecular and functional characterization of CD59 from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.

    Science.gov (United States)

    Gan, Zhen; Wang, Bei; Zhou, Wei; Lu, Yishan; Zhu, Weiwei; Tang, Jufen; Jian, JiChang; Wu, Zaohe

    2015-05-01

    CD59, the major inhibitor of membrane attack complex, plays a crucial role in regulation of complement activation. In this paper, a CD59 gene of Nile tilapia, Oreochromis niloticus (designated as On-CD59) was cloned and its expression pattern under the stimulation of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for complement-inhibitory activity were detected in the deduced amino acid sequence of On-CD59. In healthy Nile tilapia, the On-CD59 transcripts could be detected in all the examined tissues, with the most abundant expression in the brain. When immunized with inactivated S. agalactiae, there was a clear time-dependent expression pattern of On-CD59 in the skin, brain, head kidney, thymus and spleen, with quite different kinetic expressions. The assays for the complement-inhibitory activity suggested that recombinant On-CD59 protein had a species-selective inhibition of complement. Moreover, our works showed that recombinant On-CD59 protein may possess both binding activities to PGN and LTA and inhibiting activity of S. agalactiae. These findings indicated that On-CD59 may play important roles in the immune response to S. agalactiae in Nile tilapia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Natural coinfection by Streptococcus agalactiae and Francisella noatunensis subsp. orientalis in farmed Nile tilapia (Oreochromis niloticus L.).

    Science.gov (United States)

    Assis, G B N; Tavares, G C; Pereira, F L; Figueiredo, H C P; Leal, C A G

    2017-01-01

    Streptococcus agalactiae and Francisella noatunensis subsp. orientalis (Fno) are important pathogens for farm-raised tilapia worldwide. There are no reports of coinfection caused by S. agalactiae and Fno in fish. This study aimed to determine the aetiology of atypical mortalities in a cage farm of Nile tilapia and to characterize the genetic diversity of the isolates. Fifty-two fish were sampled and subjected to parasitological and bacteriological examination. The S. agalactiae and Fno isolates were genotyped using MLST and REP-PCR, respectively. Whole-genome sequencing was performed to confirm the MLST results. Seven fish were shown coinfected by S. agalactiae and Fno. Chronic hypoxia and a reduction in the water temperature were determined as risk factors for coinfection. Fno isolates were shown clonally related in REP-PCR. The MLST analysis revealed that the S. agalactiae isolates from seven coinfected fish were negative for the glcK gene; however, these were determined to be members of clonal complex CC-552. This is the first description of coinfection by S. agalactiae and Fno in farm-raised Nile tilapia. The coinfection was predisposed by chronic hypoxia and was caused by the main genotypes of S. agalactiae and Fno reported in Brazil. Finally, a new S. agalactiae genotype with glcK gene partially deleted was described. © 2016 John Wiley & Sons Ltd.

  8. Performance and body composition of Nile tilapia fed diets supplemented with AminoGut® during sex reversal period

    Directory of Open Access Journals (Sweden)

    Themis Sakaguti Graciano

    2014-09-01

    Full Text Available The present study was to evaluate the effects of the commercial product AminoGut® (Ajinomoto, SP, a source of glutamine and glutamate, on performance and body composition of Nile tilapia fingerlings. A study was conducted with 26,000 Gift strain tilapias, with seven days of age during the sex reversal, with initial weight and length of 0.037±0.09 g and 13.28±0.78 mm. The fish were distributed in a completely randomized design with five treatments and four replications, totaling 1,300 fish/tank of 0,5m3 each one. Control diet was used with approximately 500 g/kg of crude protein and 3,840 kcal/ kg of digestible energy. The AminoGut® was added to the control diet at a ratio of 5, 10, 15 and 20g/kg to replace L-alanine. Each diet was provided 10 times per day at intervals of one hour, from 8:00 until 17:00, for 30 days. No effect was observed on weight gain (p>0.05 in fish fed with increasing levels of Aminogut®. However, a positive linear effect (p<0.05 on feed conversion, protein efficiency ratio and survival of the fish supplemented was verified. The inclusion of Aminogut® up to 20 g/kg improves the feed conversion, protein efficiency ratio and survival, parameters of Nile tilapia during sex reversal.

  9. Morphology and muscle gene expression in GIFT and Supreme Nile tilapia varieties reared in two cultivation systems.

    Science.gov (United States)

    Lima, E C S; Povh, J A; Otonel, R A A; Leonhardt, J H; Alfieri, A A; Headley, S A; Souza, F P; Poveda-Parra, A R; Furlan-Murari, P J; Lopera-Barrero, N M

    2017-03-16

    Tissue growth in most fishes occurs by muscular hyperplasia and hypertrophy, which are influenced by different regulatory factors, such as myostatin. The current study evaluated the influence of cultivation in hapas and earthen ponds on the diameter of white muscle fibers and on the myostatin (MSTN-1) gene in GIFT and Supreme varieties of tilapia. Fish of both varieties were reared for 204 days and then divided into four developmental stages. White muscle samples, corresponding to 100 fibers per slide, were collected from the middle region of fish of each variety and cultivation system, and were measured and divided into two classes representing hyperplasia and hypertrophy. Samples were subjected to real-time PCR to analyze gene expression. Hyperplasia decreased during the developing stages, coupled with increased hypertrophy. There was a higher rate of hypertrophy in fish raised in earthen ponds when compared to those raised in hapas, during juvenile and developing phases, and greater hypertrophic growth was observed in GIFT specimens when compared to Supreme specimens in earthen ponds. Since increased MSTN-1 gene expression was observed in GIFT specimens during the developing phase in pond cultivations, and in Supreme tilapia in hapas, MSTN-1 expression is related to greater hypertrophy. These results demonstrate the capacity for increased muscle growth in earthen pond cultivation in which the GIFT variety developed best. How the environment affects the growth of different tilapia varieties may be employed to optimize culture management and genetic improvement programs. Further investigations should aim to describe mechanisms affecting muscle growth and development.

  10. Characterizing bacterial communities in tilapia pond surface sediment and their responses to pond differences and temporal variations.

    Science.gov (United States)

    Fan, Limin; Barry, Kamira; Hu, Gengdong; Meng, Shunlong; Song, Chao; Qiu, Liping; Zheng, Yao; Wu, Wei; Qu, Jianhong; Chen, Jiazhang; Xu, Pao

    2017-01-01

    Bacterial community compositions in the surface sediment of tilapia ponds and their responses to pond characteristics or seasonal variations were investigated. For that, three ponds with different stocking densities were selected to collect the samples. And the method of Illumina high-throughput sequencing was used to amplify the bacterial 16S rRNA genes. A total of 662, 876 valid reads and 5649 operational taxonomic units were obtained. Further analysis showed that the dominant phyla in all three ponds were Proteobacteria, Bacteroidetes, Chloroflexi, and Acidobacteria. The phyla Planctomycetes, Firmicutes, Chlorobi, and Spirochaetae were also relatively abundant. Among the eight phyla, the abundances of only Proteobacteria, Bacteroidetes, Firmicutes, and Spirochaetae were affected by seasonal variations, while seven of these (with the exception of Acidobacteria) were affected by pond differences. A comprehensive analysis of the richness and diversity of the bacterial 16S rRNA gene, and of the similarity in bacterial community composition in sediment also showed that the communities in tilapia pond sediment were shaped more by pond differences than by seasonal variations. Linear discriminant analysis further indicated that the influences of pond characteristics on sediment bacterial communities might be related to feed coefficients and stocking densities of genetically improved farmed tilapia (GIFT).

  11. Dietary supplementation of cumin (Cuminum cyminum preventing streptococcal disease during first-feeding of Mozambique tilapia (Oreochromis mossambicus

    Directory of Open Access Journals (Sweden)

    Sevdan Yılmaz

    2013-01-01

    Full Text Available This study was conducted to investigate the effect of dietary cumin (Cuminum cyminum powder (CP as a feed additive on growth performance and disease resistance during first-feeding of Mozamique tilapia (Oreochromis mossambicus. Five isonitrogenous (40% crude protein and isocaloric (18.9 kj g-1 diets were formulated to contain 0 (control, 0.5, 1, 1.5, and 2.0% CP. In a 45-day feeding trial, 15 plastic tanks (21 L were stocked with 40 fry (0.012 ± 0.001 g each. After feeding experiment, fish were infected with Streptococcus iniae and mortalities were recorded. The second-order polynomial regression indicated that a dietary CP level of 1.14% provided the best survival rate challenge infection with S. iniae, growth performance and feed utilization. In conclusion, CP can be used as growth promoter to improve feed utilization and weight gain in tilapia fry, and it can be also used as an antimicrobial agent during first-feeding of O. mossambicus. Therefore, CP can be suggested as an alternative to antibiotics in controlling streptococcal disease in tilapia culture.

  12. Defining a breeding objective for Nile tilapia that takes into account the diversity of smallholder production systems.

    Science.gov (United States)

    Omasaki, S K; van Arendonk, J A M; Kahi, A K; Komen, H

    2016-10-01

    In general, livestock and fish farming systems in developing countries tend to be highly diverse in terms of agro-ecological conditions and market orientation. There are no studies that have investigated if and how this diversity translates to varying preferences for breeding objective traits. This is particularly important for breeding programmes that are organized on a national level (e.g. government-supported nucleus breeding programmes). The aim of this study was to investigate whether Nile tilapia farmers with diverse production systems and economic constraints have different preferences for breeding objective traits. The second objective was to derive a consensus breeding goal, using weighted goal programming that could be used for a national breeding programme for Nile tilapia. A survey was conducted among 100 smallholder Nile tilapia farmers in Kenya to obtain preference values for traits of economic importance, by using multiple pairwise comparisons. Individual and group preference values were estimated using analytical hierarchy process. Low-income farmers preferred harvest weight, while medium- and high-income farmers preferred growth rate and survival. Grouping farmers according to market objective (fingerling production or fattening) showed that fingerling producers preferred growth rate and survival, while fattening farmers preferred harvest weight, height and thickness. Weighted goal programming was used to obtain consensus preference values, and these were used to derive desired gains for a breeding goal of a national breeding programme that takes into account the diversity of smallholder production systems. © 2016 Blackwell Verlag GmbH.

  13. Effect of methomyl on sex steroid hormone and vitellogenin levels in serum of male tilapia (Oreochromis niloticus) and recovery pattern.

    Science.gov (United States)

    Meng, Shun-Long; Qiu, Li-Ping; Hu, Geng-Dong; Fan, Li-Min; Song, Chao; Zheng, Yao; Wu, Wei; Qu, Jian-Hong; Li, Dan-Dan; Chen, Jia-Zhang; Xu, Pao

    2017-07-01

    Tilapia were exposed to sub-lethal concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, then transferred to methomyl-free water for 18 days. E 2 , T, 11-KTand VTG in serum were examined. There were no significant changes in all the parameters in serum of tilapia exposed to 0.2 μg/L and 2 μg/L methomyl compared to the control. However, 20 μg/L and 200 μg/L have the potential to disrupt the endocrine system of male tilapia, as shown by its ability to increase VTG and E 2 and decrease T and 11-KT in serum. Thus it would appear the no observed adverse effect level for sexual steroid hormones of methomyl is lower than 2 μg/L. Recovery data showed that the effects produced by 20μg/L were reversible but not at 200μg/L. Furthermore, the sensitivity of above parameters to methomyl followed the order of VTG>E 2 >11-KT>T>GSI, suggesting VTG being the better biomarkers. © 2017 Wiley Periodicals, Inc.

  14. Evaluation on subcellular partitioning and biodynamics of pulse copper toxicity in tilapia reveals impacts of a major environmental disturbance.

    Science.gov (United States)

    Ju, Yun-Ru; Yang, Ying-Fei; Tsai, Jeng-Wei; Cheng, Yi-Hsien; Chen, Wei-Yu; Liao, Chung-Min

    2017-07-01

    Fluctuation exposure of trace metal copper (Cu) is ubiquitous in aquatic environments. The purpose of this study was to investigate the impacts of chronically pulsed exposure on biodynamics and subcellular partitioning of Cu in freshwater tilapia (Oreochromis mossambicus). Long-term 28-day pulsed Cu exposure experiments were performed to explore subcellular partitioning and toxicokinetics/toxicodynamics of Cu in tilapia. Subcellular partitioning linking with a metal influx scheme was used to estimate detoxification and elimination rates. A biotic ligand model-based damage assessment model was used to take into account environmental effects and biological mechanisms of Cu toxicity. We demonstrated that the probability causing 50% of susceptibility risk in response to pulse Cu exposure in generic Taiwan aquaculture ponds was ~33% of Cu in adverse physiologically associated, metabolically active pool, implicating no significant susceptibility risk for tilapia. We suggest that our integrated ecotoxicological models linking chronic exposure measurements with subcellular partitioning can facilitate a risk assessment framework that provides a predictive tool for preventive susceptibility reduction strategies for freshwater fish exposed to pulse metal stressors.

  15. A genome scan revealed significant associations of growth traits with a major QTL and GHR2 in tilapia

    Science.gov (United States)

    Liu, Feng; Sun, Fei; Xia, Jun Hong; Li, Jian; Fu, Gui Hong; Lin, Grace; Tu, Rong Jian; Wan, Zi Yi; Quek, Delia; Yue, Gen Hua

    2014-01-01

    Growth is an important trait in animal breeding. However, the genetic effects underpinning fish growth variability are still poorly understood. QTL mapping and analysis of candidate genes are effective methods to address this issue. We conducted a genome-wide QTL analysis for growth in tilapia. A total of 10, 7 and 8 significant QTLs were identified for body weight, total length and standard length at 140 dph, respectively. The majority of these QTLs were sex-specific. One major QTL for growth traits was identified in the sex-determining locus in LG1, explaining 71.7%, 67.2% and 64.9% of the phenotypic variation (PV) of body weight, total length and standard length, respectively. In addition, a candidate gene GHR2 in a QTL was significantly associated with body weight, explaining 13.1% of PV. Real-time qPCR revealed that different genotypes at the GHR2 locus influenced the IGF-1 expression level. The markers located in the major QTL for growth traits could be used in marker-assisted selection of tilapia. The associations between GHR2 variants and growth traits suggest that the GHR2 gene should be an important gene that explains the difference in growth among tilapia species. PMID:25435025

  16. CARACTERIZACIÓN DE COPRODUCTOS DE LA INDUSTRIA DEL FILETEADO DE TILAPIA NILÓTICA (Oreochromis niloticus Y TRUCHA ARCOÍRIS (Oncorhynchus mykiss EN COLOMBIA

    Directory of Open Access Journals (Sweden)

    A. Osorio

    2013-01-01

    Full Text Available La industria del fileteado de tilapia y trucha genera cantidades significativas de coproductos de los cuales no existe suficiente información disponible sobre su composición y calidad. Esta investigación determinó algunos componentes nutricionales y microbiológicos de coproductos obtenidos en plantas exportadoras de filetes de tilapia nilótica y trucha arcoíris en Colombia. El esqueleto mostró el mayor aporte de cenizas (tilapia: 14,12 ± 0,16%; trucha: 6,18 ± 0,06%, calcio (tilapia: 5,70 ± 0,04%; trucha: 1,72 ± 0,08% y fósforo (tilapia: 1,89 ± 0,06%; trucha: 0,84 ± 0,03%, mientras que los recortes presentaron la mayor concentración de extracto etéreo (tilapia: 30,10 ± 0,58%; trucha: 17,50 ± 0,51% y la carne mecánicamente separada, los mayores contenidos de humedad (tilapia: 70,38 ± 0,18%; trucha: 72,93 ± 0,3% y proteína (tilapia: 14,32 ± 0,03%; trucha: 18,88 ± 0,05%. El mayor aporte de ácidos grasos polinsaturados (AGPI, como porcentaje del total de ácidos grasos identificados, se encontró en esqueleto de tilapia (17,27% y en recortes de trucha (38,68%, con relaciones n6/n3 de 2,67 y 0,71, respectivamente. En general, los coproductos estudiados cumplieron con los estándares microbiológicos exigidos por la normatividad colombiana (Resolución 122 de 2012 del Ministerio de Salud y Protección Social que establece los requisitos fisicoquímicos y microbiológicos que deben cumplir los productos de la pesca, en particular pescados, moluscos y crustáceos para consumo humano. Los resultados muestran que los coproductos estudiados contienen un importante aporte de proteína, cenizas, ácidos grasos poli-insaturados y adecuada calidad microbiológica, con potencial para alimentación humana o animal.

  17. Species-specific content of As, Pb, and other elements in pangas (Pangasianodon hypophthalmus) and tilapia (Oreochromis niloticus) from aquaculture ponds in southern Bangladesh

    DEFF Research Database (Denmark)

    Marcussen, Helle; Alam, Md. Ariful; Rahman, Md. Mizanur

    2014-01-01

    Content of arsenic and lead and 10 other potentially toxic elements (Ba, Ce, Cr, Cu, Fe,Mg,Mn, Se, Sr and Zn) was determined in tilapia and pangas from aquaculture ponds in southern Bangladesh. Tilapia had 1.6- to 4.3-fold higher content of Mn, As, Sr, and Ba than pangas, possibly caused...... by different feeding habits of the two fish. The other elements had similar concentrations in both species. Content of As in tilapia and pangas was 0.37 and 0.11 μg g−1, respectively, while Pb made up 0.056 and 0.051 μg g−1, respectively. Water treatment during the farming period (sand filtration and probiotic...... bacteria) and final depuration in groundwater for up to 48 h had no effect on content of the elements. For As, consumption of 100 g fresh fish per day contained 1.3% (pangas) and 5% (tilapia) of the maximum tolerable daily intake according to FAO recommendations. Relative to whole tilapia froma lake near...

  18. The effect of melanin-free extract from Sepia esculenta ink on lipid peroxidation, protein oxidation and water-holding capacity of tilapia fillet during cold storage.

    Science.gov (United States)

    Duan, Zhen-Hua; Liu, Hua-Zhong; Luo, Ping; Gu, Yi-Peng; Li, Yan-Qun

    2018-03-14

    Preservative effect of melanin-free extract of Sepia esculenta ink (MFESI) on Sparus latus fillet has been verified in our previous work. This study aims to further approach the mechanism of MFESI for extending the shelf-life of fish fillet during cold storage. Tilapia fillets were treated with different dosage of MFESI (0, 15, 25 and 35 mg/ml) and packed with preservative film for succedent cold-storage at 4 °C for scheduled time. Contents of total volatile basic nitrogen and sulfydryl and carbanyl groups were measured for evaluating protein oxidation. Malondialdehyde contents were measured for estimating lipid peroxidation and loss of water was used to determine water-holding capacity of fillet. The data indicated that MFESI not only possessed certain degree of antioxidant capacity in vitro, also lengthened shelf-life of tilapia fillet in cold-storage condition. Apart from 15 mg/ml, both 25 and 35 mg/ml of MFESI obviously prevented lipid and protein from oxidation and reduced loss of water from tilapia fillets, and the latter was more effective than the former. MFESI can repress lipid peroxidation and protein oxidation and reduce water loss, maintain the tilapia fillets quality and, thus, it could be an effective and natural preservative for extending the shelf-life of tilapia fillets during cold storage.

  19. Determination of presence and quantification of cadmium, lead and copper in Nile tilapia (Oreochromis niloticus fillets obtained from three cold storage plants in the state of Parana, Brazil

    Directory of Open Access Journals (Sweden)

    Alexandre Nobuhiro Tajiri

    2011-06-01

    Full Text Available Pisciculture is an economic activity that is steadily growing in the state of Parana, Brazil, and Nile tilapia (Oreochromis niloticus is one of the widely cultivated species in this state. Tilapia is not only a very nutritious food, but also an important indicator of environmental contamination. This study aimed to verify contamination by cadmium, copper and lead in tilapia fillets, and to compare the found values to international legislations. Were collected 135 samples of tilapia fillets, between July 2006 and May 2007, in three fish stores located in regions west and north of Paraná State. Samples of tilapia fillet were analyzed in relation to the presence of cadmiun, lead and copper, using atomic absorption spectrophotometry. Lead has not been detected in the analyses. Cadmium has been detected in three samples, on concentrations of 0.012 µg.g-1, 0.011 µg.g-1 and 0.014 µg.g-1. Copper has been detected in all fillets, and the average concentration of each cold storage plant was of 0.122 µg.g-1, 0.106 µg.g-1 and 0.153 µg.g-1. The concentrations found in this study are within the limits allowed by both the European and the Australian legislations.

  20. Dynamical coupling of PBPK/PD and AUC-based toxicity models for arsenic in tilapia Oreochromis mossambicus from blackfoot disease area in Taiwan

    International Nuclear Information System (INIS)

    Liao, C.-M.; Liang, H.-M.; Chen, B.-C.; Singh Sher; Tsai, J.-W.; Chou, Y.-H.; Lin, W.-T.

    2005-01-01

    A physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) models were developed for arsenic (As) in tilapia Oreochromis mossambicus from blackfoot disease area in Taiwan. The PBPK/PD model structure consisted of muscle, gill, gut wall, alimentary canal, and liver, which were interconnected by blood circulation. We integrate the target organ concentrations and dynamic response describing uptake, metabolism, and disposition of As and the associated area-under-curve (AUC)-based toxicological dynamics following an acute exposure. The model validations were compared against the field observations from real tilapia farms and previously published uptake/depuration experimental data, indicating that predicted and measured As concentrations in major organs of tilapia were in good agreement. The model was utilized to reasonably simulate and construct a dose-dependent dynamic response between mortality effect and equilibrium target organ concentrations. Model simulations suggest that tilapia gills may serve as a surrogate sensitive biomarker of short-term exposure to As. This integrated As PBPK/PD/AUC model quantitatively estimates target organ concentration and dynamic response in tilapia and is a strong framework for future waterborne metal model development and for refining a biologically-based risk assessment for exposure of aquatic species to waterborne metals under a variety of scenarios. - Integrated toxicity models can identify dynamic responses of fish to arsenic

  1. Mossambicus tilapia (Oreochromis mossambicus) collected from water bodies impacted by urban waste carries extended-spectrum beta-lactamases and integron-bearing gut bacteria.

    Science.gov (United States)

    Marathe, Nachiket P; Gaikwad, Swapnil S; Vaishampayan, Ankita A; Rasane, Mandar H; Shouche, Yogesh S; Gade, Wasudev N

    2016-09-01

    Oreochromis mossambicus (Peters 1852) (Tilapia) is one of the most consumed fish globally. Tilapia thrives well in environments polluted by urban waste, which invariably contain antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Thus, Tilapia surviving in such polluted environments may serve as a potential source for dissemination of ARGs. To investigate this, we isolated bacterial strains from gut of Tilapia found in polluted rivers and lakes near Pune, India, and studied the prevalence of resistance genes by molecular methods. A total of 91 bacterial strains were obtained, which include fish pathogens and human pathogens such as Aeromonas hydrophila, Klebsiella pneumoniae, E. coli, Serratia marcescens, Enterobacter spp. and Shigella spp. Overall the prevalence of class 1 integrons, class 2 integrons, extended-spectrum betalactamases (ESBLs) blaCTX-M, blaSHV and aac(6')-Ib-cr gene was 38 percent, 24 percent, 38 percent, 31 percent and 31 percent respectively. Forty-two percent of the Enterobacteriaceae strains carried blaCTX-M gene, which is a common ESBL gene in clinics. The study demonstrates that tilapia found in the polluted waters can serve as reservoirs and an alternative route for human exposure to clinically important ARG-carrying bacteria. The consumption and handling of these fish may pose a potential health risk.

  2. Genome-Wide Identification and Transcriptome-Based Expression Profiling of the Sox Gene Family in the Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Wei, Ling; Yang, Chao; Tao, Wenjing; Wang, Deshou

    2016-02-23

    The Sox transcription factor family is characterized with the presence of a Sry-related high-mobility group (HMG) box and plays important roles in various biological processes in animals, including sex determination and differentiation, and the development of multiple organs. In this study, 27 Sox genes were identified in the genome of the Nile tilapia (Oreochromis niloticus), and were classified into seven groups. The members of each group of the tilapia Sox genes exhibited a relatively conserved exon-intron structure. Comparative analysis showed that the Sox gene family has undergone an expansion in tilapia and other teleost fishes following their whole genome duplication, and group K only exists in teleosts. Transcriptome-based analysis demonstrated that most of the tilapia Sox genes presented stage-specific and/or sex-dimorphic expressions during gonadal development, and six of the group B Sox genes were specifically expressed in the adult brain. Our results provide a better understanding of gene structure and spatio-temporal expression of the Sox gene family in tilapia, and will be useful for further deciphering the roles of the Sox genes during sex determination and gonadal development in teleosts.

  3. Dynamical coupling of PBPK/PD and AUC-based toxicity models for arsenic in tilapia Oreochromis mossambicus from blackfoot disease area in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Liao, C.-M. [Ecotoxicological Modeling Center, Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan 10617 (China)]. E-mail: cmliao@ntu.edu.tw; Liang, H.-M. [Ecotoxicological Modeling Center, Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan 10617 (China); Chen, B.-C. [Department of Post-Modern Agriculture, Mingdao University, Changhua, Taiwan 52345 (China); Singh Sher [Center of Genomics Medicine, School of Medicine, National Taiwan University, Taipei, Taiwan 10617 (China); Tsai, J.-W. [Ecotoxicological Modeling Center, Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan 10617 (China); Chou, Y.-H. [Ecotoxicological Modeling Center, Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan 10617 (China); Lin, W.-T. [Environment Change Research Center, Academia Sinica, Nankang, Taipei, Taiwan 11517 (China)

    2005-05-01

    A physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) models were developed for arsenic (As) in tilapia Oreochromis mossambicus from blackfoot disease area in Taiwan. The PBPK/PD model structure consisted of muscle, gill, gut wall, alimentary canal, and liver, which were interconnected by blood circulation. We integrate the target organ concentrations and dynamic response describing uptake, metabolism, and disposition of As and the associated area-under-curve (AUC)-based toxicological dynamics following an acute exposure. The model validations were compared against the field observations from real tilapia farms and previously published uptake/depuration experimental data, indicating that predicted and measured As concentrations in major organs of tilapia were in good agreement. The model was utilized to reasonably simulate and construct a dose-dependent dynamic response between mortality effect and equilibrium target organ concentrations. Model simulations suggest that tilapia gills may serve as a surrogate sensitive biomarker of short-term exposure to As. This integrated As PBPK/PD/AUC model quantitatively estimates target organ concentration and dynamic response in tilapia and is a strong framework for future waterborne metal model development and for refining a biologically-based risk assessment for exposure of aquatic species to waterborne metals under a variety of scenarios. - Integrated toxicity models can identify dynamic responses of fish to arsenic.

  4. Genome-Wide Identification and Transcriptome-Based Expression Profiling of the Sox Gene Family in the Nile Tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Ling Wei

    2016-02-01

    Full Text Available The Sox transcription factor family is characterized with the presence of a Sry-related high-mobility group (HMG box and plays important roles in various biological processes in animals, including sex determination and differentiation, and the development of multiple organs. In this study, 27 Sox genes were identified in the genome of the Nile tilapia (Oreochromis niloticus, and were classified into seven groups. The members of each group of the tilapia Sox genes exhibited a relatively conserved exon-intron structure. Comparative analysis showed that the Sox gene family has undergone an expansion in tilapia and other teleost fishes following their whole genome duplication, and group K only exists in teleosts. Transcriptome-based analysis demonstrated that most of the tilapia Sox genes presented stage-specific and/or sex-dimorphic expressions during gonadal development, and six of the group B Sox genes were specifically expressed in the adult brain. Our results provide a better understanding of gene structure and spatio-temporal expression of the Sox gene family in tilapia, and will be useful for further deciphering the roles of the Sox genes during sex determination and gonadal development in teleosts.

  5. Streptococcus agalactiae: HASTA AHORA EL ÚNICO Streptococcus PATÓGENO DE TILAPIAS CULTIVADAS EN COLOMBIA

    Directory of Open Access Journals (Sweden)

    AP Jiménez

    2007-01-01

    Full Text Available Las estreptococosis son un conjunto de enfermedades ocasionadas por un grupo de cocos Gram positivos con similares signologías que involucran distintos órganos en los individuos afectados. La identiÀcación precisa de cada uno de estos microorganismos no se logra de manera deÀnitiva por los métodos tradicionales microbiológicos, por lo que se debe acudir a otro tipo de metodologías como las técnicas de biología molecular. En 1999 se identiÀcó por primera vez en Colombia la estreptococosis en híbridos de tilapias de cultivo. La pos-terior secuenciación del ADN de distintos aislamientos obtenidos de varias regiones del país demostró un 98,8% de aÀnidad con el Streptococcus agalactiae. El presente estudio pretende deÀnir si hasta la fecha existe solo esta especie de Streptococcus en el país causan-do infección o enfermedad en tilapias de cultivo o, por el contrario, son varias las especies que intervienen en los cuadros infecciosos. Se evaluaron aislamientos de tejidos, de agua y fango de los sitios de cultivo, así como de lugares de expendio de tilapia roja (Oreochromissp., utilizando técnicas microbiológicas, inmunoperoxidasa indirecta (IPI y PCR, espe-cíÀcas para el aislamiento e identiÀcación del S. agalactiae. Los resultados del presente estudio demostraron que hasta la fecha en el país únicamente se ha identiÀcado la especie S. agalactiae causando infección o enfermedad en tilapias. No tenemos evidencia de que otros Streptococcus reportados internacionalmente como S. iniae y otros Gram positivos causen estreptococosis en Colombia.La tilapia parece ser el principal reservorio del S. agalactiae en el país, y el riesgo zoonótico, aunque existe, es mínimo si se toman las medidas apropia-das de bioseguridad.

  6. Culuwiya cichlidorum n. sp. (Digenea: Haploporidae) from the black-belt cichlid Vieja maculicauda (Pisces: Cichlidae) from Nicaragua

    Czech Academy of Sciences Publication Activity Database

    Aguirre-Macedo, M. L.; Scholz, Tomáš

    2005-01-01

    Roč. 91, č. 6 (2005), s. 1379-1384 ISSN 0022-3395 R&D Projects: GA AV ČR IAA6022404 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trematoda * Haploporidae * taxonomy Subject RIV: EG - Zoology Impact factor: 1.524, year: 2005

  7. Combination of garlic - shatterstone herb powder to control Streptococcus agalactiae infection in tilapia

    Directory of Open Access Journals (Sweden)

    Ririn Nurul Fauziah

    2015-10-01

    Full Text Available ABSTRACT This study was aimed at determining potential of combination powder of garlic Allium sativum-shatterstone herb Phyllanthus niruri supplemented in feed against S. agalactiae infection in tilapia. Four concentrations of combination powder of A. sativum-P. Niruri; 20+5, 20+10, 20+15 and 20+20 ppt respectively were investigated for their ability to inhibit bacterial fish pathogen. Combination dose of 20+15 ppt produced the highest inhibitory zones in in vitro test. In vivo test consisted of three treatments with three replications, namely positive control (K+, negative control (K- and the treatment of A. sativum-P. niruri suplemented in feed (BM.  The test perfomed on tilapia with weight of 10.33 ± 1.63 g and were reared at density of 10 ind/aquarium. The fish was fed for 14 days, then injected intraperitoneally with 0.1 mL S. agalactiae at concentration of 105 cfu/mL for positive control and BM groups. Survival, growth rate, feed response, hematological and water quality parameters were observed for 10 days. This study showed that the suplemented-feed-fish (BM showed better growth rate, feed response, and survival (83.3% than positive control (36.7% at P<0.05. In addition, A. sativum-P. niruri suplemented in feed was also able to enhance the immune response by increasing phagocytic activity. Keywords: Streptococcus agalactiae, phytopharmacy, Allium sativum-Phyllanthus niruri, tilapia  ABSTRAK Penelitian ini bertujuan untuk menganalisis potensi campuran tepung bawang putih Allium sativum-meniran Phyllanthus niruri dalam pakan terhadap pencegahan infeksi bakteri S. agalactiae pada ikan nila. Empat konsentrasi campuran tepung bawang putih-meniran yaitu 20+5 ppt, 20+10 ppt, 20+15 ppt dan 20+20 ppt masing-masing diuji kemampuannya dalam  menghambat bakteri patogen pada ikan. Campuran dosis 20+15 ppt menghasilkan zona hambat terbaik dalam uji in vitro. Uji in vivo terdiri atas tiga perlakuan dengan tiga ulangan yaitu kontrol positif

  8. Effects of population density on growth and production of Tilapia in monoculture

    Directory of Open Access Journals (Sweden)

    TH Majumder

    2017-12-01

    Full Text Available The experiment was conducted to determine the effect of population density on growth and production of Tilapia (monosex GIFT tilapia in monoculture system for a period of 110 days. The experiment was carried out in six earthen ponds, which were situated in the Bangladesh Agricultural University Campus, Mymensingh. The experiment was carried out under three treatments each with two replications. Fish population density was 200 fish per decimal under treatment-I, 400 fish per decimal under treatment-II and 600 fish per decimal under treatment-III. In the ponds supplementary feed of wheat bran and rice bran mixture were used daily at the rate of 46 g, 92 g and 136 g per decimal under treatment-I, II, and III, respectively. The average initial length and weight of tilapia were 4.63 cm and 2.82 g respectively. The ponds were fertilized fortnightly with urea and TSP at the rates of 60 g and 90 g, respectively. During experimental period, the ranges of water temperature (25.82 to 29.80 ºC, transparency (28.00 to 38.00 cm, dissolved oxygen (5.50 to 8.30 mg/L, pH (7.00 to 7.90, total alkalinity (130.00 to 200.00 mg/L, free CO2 (2.00 to 6.00 mg/L, phosphate-phosphorus (1.20 to 2.30 mg/L, and nitrate-nitrogen (3.20 to 4.00 mg/L were within the productive range and more or less similar in all the ponds under three treatments. There were 25 genera of phytoplankton under five major groups and 10 genera of zooplankton under three major groups in the experimental ponds. Mean survival rate of fish under treatment-I, treatment-II, and treatment-III were 82.75%, 77.12% and 74.33% respectively. The calculated net fish production under treatment-I was 6.75 ton/ha/yr and that of the ponds under treatment-II was 10.26 ton/ha/yr and that of the ponds under treatment-III was 12.15 ton/ha/yr. The net fish production under treatment-II and treatment-III were 152% and 180% higher than that of treatment-I, taking net fish production under treatment-I for 100%. According to

  9. Agonistic and reproductive behaviors in males of red hybrid tilapia, Oreochromis niloticus (Linnaeus, 1758 x O. mossambicus (Peters, 1852 (Osteichthyes: Cichlidae

    Directory of Open Access Journals (Sweden)

    APT Medeiros

    Full Text Available The red hybrid tilapia, Oreochromis niloticus (Linnaeus, 1758 x O. mossambicus (Peters, 1852 is a fertile hybrid used in the semi-intensive level of fish culture in the Northeast of Brazil. It is a territorial cichlid and is highly aggressive towards conspecifics during the breeding season. The purpose of this study was to investigate and describe the aggressive behaviour displayed by the males of this hybrid in non-reproductive and reproductive contexts. Behavioural observations revealed that aggression displayed by the reproductive males of red hybrid tilapia included threatening, undulation, parallel, lateral and frontal attacks, chasing, escape and submission. Possession of a territory influenced male aggressiveness, which was more intense in their own territory than that observed in a neutral situation. The males built nests, irrespective of female presence. All the behavioural patterns were in accordance with those previously described for one parental species, the Nile tilapia, O. niloticus.

  10. Identities among actin-encoding cDNAs of the Nile tilapia (Oreochromis niloticus and other eukaryote species revealed by nucleotide and amino acid sequence analyses

    Directory of Open Access Journals (Sweden)

    Andréia B. Poletto

    2008-01-01

    Full Text Available Actin-encoding cDNAs of Nile tilapia (Oreochromis niloticus were isolated by RT-PCR using total RNA samples of different tissues and further characterized by nucleotide sequencing and in silico amino acid (aa sequence analysis. Comparisons among the actin gene sequences of O. niloticus and those of other species evidenced that the isolated genes present a high similarity to other fish and other vertebrate actin genes. The highest nucleotide resemblance was observed between O. niloticus and O. mossambicus a-actin and b-actin genes. Analysis of the predicted aa sequences revealed two distinct types of cytoplasmic actins, one cardiac muscle actin type and one skeletal muscle actin type that were expressed in different tissues of Nile tilapia. The evolutionary relationships between the Nile tilapia actin genes and diverse other organisms is discussed.

  11. Longitudinal analyses of correlated response efficiencies of fillet traits in Nile tilapia.

    Science.gov (United States)

    Turra, E M; Fernandes, A F A; de Alvarenga, E R; Teixeira, E A; Alves, G F O; Manduca, L G; Murphy, T W; Silva, M A

    2018-03-01

    Recent studies with Nile tilapia have shown divergent results regarding the possibility of selecting on morphometric measurements to promote indirect genetic gains in fillet yield (FY). The use of indirect selection for fillet traits is important as these traits are only measurable after harvesting. Random regression models are a powerful tool in association studies to identify the best time point to measure and select animals. Random regression models can also be applied in a multiple trait approach to analyze indirect response to selection, which would avoid the need to sacrifice candidate fish. Therefore, the aim of this study was to investigate the genetic relationships between several body measurements, weight and fillet traits throughout the growth period and to evaluate the possibility of indirect selection for fillet traits in Nile tilapia. Data were collected from 2042 fish and was divided into two subsets. The first subset was used to estimate genetic parameters, including the permanent environmental effect for BW and body measurements (8758 records for each body measurement, as each fish was individually weighed and measured a maximum of six times). The second subset (2042 records for each trait) was used to estimate genetic correlations and heritabilities, which enabled the calculation of correlated response efficiencies between body measurements and the fillet traits. Heritability estimates across ages ranged from 0.05 to 0.5 for height, 0.02 to 0.48 for corrected length (CL), 0.05 to 0.68 for width, 0.08 to 0.57 for fillet weight (FW) and 0.12 to 0.42 for FY. All genetic correlation estimates between body measurements and FW were positive and strong (0.64 to 0.98). The estimates of genetic correlation between body measurements and FY were positive (except for CL at some ages), but weak to moderate (-0.08 to 0.68). These estimates resulted in strong and favorable correlated response efficiencies for FW and positive, but moderate for FY. These results

  12. Nutritional value of Prosopis juliflora Pods in feeding Nile Tilapia (Oreochromis niloticus) Fries

    International Nuclear Information System (INIS)

    Mabrouk, H.; Hilmi, E.; Abdullah, M.

    2008-01-01

    A feeding experiment was conducted to study the effect of different levels of supplemental Prosopis juliflora on growth performance, feed utilization and chemical composition of Nile tilapia (Oreochromis niloticus) fry (1.36+-0.004). Six isonitrigenous (30.46g 100g-1 crude protein) and isocalorific (0.018 NJ g-1) diets were formulated. Diet 1 (control without supplementing P. juliflora), and diets 2, 3, 4, 5 and 6 were supplemented with different levels (20, 40, 60, 80and 100 g Kg-1) of P. juliflora respectively. The results revealed that harvested gain (g fish-1) was significantly higher (P 0 .05) for fish fed 60g Kg-1 P. juliflora, while the lowest value of harvested gain was achieved with fish fed free. P. juliflora control diet. Despite that the fish fed diet (4) obtained the highest harvesting weight, weight gain, average daily gain and specific growth rate, no significant differences (P<0.05) were observed in an average daily gain (g fish-1 day-1) between fish fed diet 3, 4, 5 and 6 and in specific growth rate (% day-1) when inclusion level of P. juliflora was increased from 20 to 40 g kg-1 in diets 2 and 3 and from 80 to 100g kg-1 in diets 5 and 6, respectively. Feed intake was increased significantly (P<0.05) with in increasing P. juliflora inclusion level in the experimental diets. No significant differences were observed between the experimental fish groups in FCR in spite of the occurrence of a slight decreasing up to 80g kg-1 and PER. Protein productive value (PPV g 100g-1) and energy utilization (EUg 100g-1) were increased significantly (P<0.05) with increasing P. juliflora inclusion level in the experimental diets up to 60g kg-1 and then decreased significantly (P<0.05). Fish whole body composition of dry matter and protein were significantly (P<0.05) affected by using P. juliflora in fish diets. Fish fed diet 4 achieved the highest values of dry matter and crude protein. The results suggested that diet supplemented with 60g kg-1 P. juliflora improved

  13. RAPD-SCAR Markers for Genetically Improved NEW GIFT Nile Tilapia (Oreochromis niloticus niloticus L.) and Their Application in Strain Identification.

    Science.gov (United States)

    Li, Si-Fa; Tang, Shou-Jie; Cai, Wan-Qi

    2010-04-01

    The NEW GIFT Nile tilapia (Oreochromis niloticus niloticus L.) is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new variety has been extended in most of areas of China. The management of genetically improved strains, including the genetic markers for identification is needed urgently. RAPD analysis was conducted and their conversion to SCAR markers was developed. From NEW GIFT Nile tilapia, two strain-specific RAPD bands, S(304 )(624 bp ) and S(36 )(568 bp ) were identified. The strain-specific RAPD bands were gel-purified, cloned, and sequenced. Locus-specific primers were then designed to amplify the strain-specific bands. PCR amplification was conducted to test the variations in allele frequencies of two converted SCAR markers among the NEW GIFT Nile tilapia and its base strains, as well as 7 additional farmed strains worldwide. The frequency of SCAR marker I (553 bp) was 85.7% in NEW GIFT Nile tilapia, but 16.7% in the base strain. The frequency of SCAR marker II (558 bp) was 91.4% in NEW GIFT Nile tilapia, but 0% - 70% in the 7 other strains. In order to confirm the utility of these two markers, an examination was conducted for a wild population from Egypt, resulted the frequency of SCAR I and II was 10% and 70%, respectively, much lower than that of New GIFT strain. The increase in allele frequency of these two SCAR markers suggests that these markers might be genetically linked to the quantitative trait loci (QTL) underlining the performance traits by long term selection, and indicate the bright potential of SCAR marker technology for tracking generations during selection progress and for distinguishing among genetically improved strain and other strains.

  14. Levels and patterns of persistent organic pollutants (POPs) in tilapia (Oreochromis sp.) from four different lakes in Tanzania: geographical differences and implications for human health.

    Science.gov (United States)

    Polder, A; Müller, M B; Lyche, J L; Mdegela, R H; Nonga, H E; Mabiki, F P; Mbise, T J; Skaare, J U; Sandvik, M; Skjerve, E; Lie, E

    2014-08-01

    In Tanzania fish is one of the most important protein sources for the rapidly increasing population. Wild fish is threatened by overfishing and pollution from agriculture, industries, mining, household effluents and vector control. To monitor possible implications for public health, the geographical differences of the occurrence and levels of persistent organic pollutants (POPs) in tilapia fish (Oreochromis sp.) from four different Tanzanian lakes were investigated in 2011. Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyls (PBDEs) and hexabromocyclododecane (HBCDD) were determined in pooled samples of tilapia muscle from Lake (L) Victoria, L. Tanganyika, L. Nyasa (also called L. Malawi) and L. Babati in Tanzania in 2011. Levels of Σ-DDTs (274 ng/g lipid weight (lw)) and sum of 7 indicator PCBs (Σ-7PCBs) (17 ng/g lw) were significantly higher in tilapia from L. Tanganyika compared to the other lakes. The highest levels of Σ-endosulfan (94 ng/g lw) were detected in tilapia from L. Victoria. Toxaphenes were detected in low levels in fish from L. Tanganyika and L. Babati. Results revealed a geographic difference in the use of DDT and endosulfan between L. Victoria and L. Tanganyika. Low ratios of DDE/DDT in tilapia from L. Tanganyika indicated an on-going use of DDT in the area. Median levels of ΣBDEs, including BDE-209, were highest in L. Victoria (19.4 ng/g lw) and BDE-209 was present in 68% of the samples from this lake. The presence of BDE-209 indicates increasing influence of imported products from heavy industrialized countries. The measured POP levels in the studied tilapia were all below MRLs of EU or were lower than recommended levels, and thus the fish is considered as safe for human consumption. They may, however, pose a risk to the fish species and threaten biodiversity. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Effects of long term feeding of Quillaja saponins on sex ratio, muscle and serum cholesterol and LH levels in Nile tilapia (Oreochromis niloticus (L)).

    Science.gov (United States)

    Francis, George; Levavi-Sivan, Berta; Avitan, Ayelet; Becker, Klaus

    2002-12-01

    Seventeen-day-old Nile tilapia fry were fed a standard diet (C) or diets containing 50-700 mg kg(-1) Quillaja saponin (QS) extract (groups S50, S150, S300, S500 and S700). After the first 8 weeks, 30 randomly selected tilapia from each of the treatments were placed in separate aquaria and fed the standard diet without saponins from then on (these were designated S50/C, S150/C, S300/C, S500/C and S700/C). The fish grew from an initial average weight of approximately 30 mg to a final average weight of 79 g during the 6-month feeding period. The difference between the average weight of C-fed tilapia and the treatment with the highest average weight after 6 months was 53.5%. The sex ratio of tilapia in the saponin-fed groups deviated from the normal 50:50 male:female ratio, with the S700 group showing a significantly higher number of males. Quillaja saponin stimulated LH release from dispersed tilapia pituitary cells in vitro. This effect was abolished in the presence of dilute calf serum. Serum LH values did not show any diet-dependent trend in either male or female tilapia in vivo. In both continuously saponin-fed and only-initially saponin-fed groups, the average serum (but not muscle) cholesterol levels in males showed an increasing trend (R(2) values of 0.62 and 0.69) with increasing dietary saponin level. It was concluded that dietary QS has the potential to change the sex-ratio in favour of males. More investigations are required to determine the mechanism of action and the optimum dietary level of QS for maximum effects.

  16. Hibridación in situ para la detección de streptococcus agalactiae en tejidos de tilapia (oreochromis sp.)

    OpenAIRE

    Pulido, E. A.; Iregui, C. A.

    2010-01-01

    La estreptococosis es uno de los problemas sanitarios más serios en la acuicultura mundial. En Colombia la enfermedad afecta de manera importante las explotaciones de tilapia. se estandarizó la técnica de hibridación in situ (HIS ) en tejidos de tilapia previamente identificados como positivos a la presencia de S. agalactiae por la técnica de inmunoperoxidasa indirecta (IPI) y microbiología. Se obtuvo señal positiva en el interior de los granulomas con u...

  17. Lethal toxicity of industrial chemicals to early life stages of Tilapia guineensis.

    Science.gov (United States)

    Ezemonye, L I N; Ogeleka, D F; Okieimen, F E

    2008-08-30

    The toxic effects of industrial chemicals on three early life stages of an economically important fish, Tilapia guineensis were investigated using the Organisation for Economic Cooperation and Development (OECD) # 203 recommended semi-static renewal bioassay. The assessment was necessary for the uncontrollable disposal of Neatex (liquid detergent) and Norust CR 486 (corrosion inhibitor) into the Niger Delta environment of Nigeria. The estimated 96-h LC(50) for 7-, 14- and 28-day-old fish in Norust CR 486 exposure was considered "more toxic" than Neatex in all life stages and was dependent on species age, exposure duration and environment. In the fresh water test, for Neatex and Norust CR 486 exposures for day 7, 14 and 28, the 96-h LC50 were 8.79, 17.10 and 82.42 mg/l and 5.55, 13.58 and 20.21 mg/l, respectively. In the brackish test, 15.42 and 46.52 mg/l, not determined (ND) and 7.35, 13.95 and 24.50mg/l were obtained. Differential toxicity was observed in the fresh and brackish water fish for the two chemicals and controls at pchemicals provides a rationale for regulatory surveillance and monitoring of both chemicals in the fragile Niger Delta environment.

  18. Study on Effect of Immune Stimulation of γ-Ray Irradiated β-Glucan on Tilapia

    International Nuclear Information System (INIS)

    Nguyen Ngoc Duy; Nguyen Quoc Hien; Dang Van Phu

    2013-01-01

    Low molecular weight β-glucan (LMWβG) and oligoβ-glucan solution were prepared by the hydrothermal steaming combination with γ-irradiation method. The efficiency of the degradation process was demonstrated by gel permeation chromatography (GPC) analysis of the average molecular weight (Mw) of β-glucan. Results showed that the Mw decreased with increasing steaming time, concentration of H 2 O 2 and doses. For LMWβG, Mw reduces from 296,600 Da to 44,400 Da when concentration of H 2 O 2 raises from 2.5% to 10% and for oligoβ-glucan Mw reduces to 7,100 Da at 16 kGy. Tilapia fish was fed with LMWβ and oligoβ-glucan of 100 ppm for 45 days, was challenged with Strep. Agalactidae bacterial to investigate immune stimulation. The results indicated that oligoβ-glucan has higher immune stimulation effect compared to LMWβG. The effect of oligoβ-glucan various concentrations of 50, 100, and 150 ppm was investigated. Results showed that survival rate was the highest for oligoβ-glucan of 150 ppm. (author)

  19. Variation of limnological parameters in a tropical lake used for tilapia cage farming

    Directory of Open Access Journals (Sweden)

    Graciele P. Venturoti

    2015-11-01

    Full Text Available The aim of this study was to assess the effects of tilapia cage culture on the water quality and sediment of Palminhas Lake during both the dry and rainy seasons. Eight sites within the lake (four in fish farms and four in areas without fish farms and one site on an affluent stream were sampled monthly from February 2011 to January 2012. Dissolved oxygen and pH were significantly lower at fish farm sites than at locations without farms, while chlorophyll a was higher at fish farm sites. Moreover, large seasonal variations were observed, which were not related to the fish farms. The Secchi disc depth and ammonia nitrogen level were significantly higher during the dry season, but temperature, dissolved oxygen, pH, total phosphorus and chlorophyll a were significantly higher during the rainy season. The affluent stream contributed substantially to lake eutrophication. Palminhas Lake is mesotrophic and has exhibited a progressive worsening in water quality over the past 20 years. These changes were not caused by fish farming alone but probably by other anthropic activities in the areas surrounding the lake.

  20. Enterococcus, Myroides, and Exiguobacterium: Bacterial Genus with Probiotic Potential for Nile Tilapia (Oreochromis niloticus Culture

    Directory of Open Access Journals (Sweden)

    Luisa Marcela Villamil Díaz

    2017-09-01

    Full Text Available 120 bacteria were isolated from tilapia intestine and screened according to the antibacterial activity against pathogens such as Aeromonas hydrophila, Edwardsiella tarda and Streptococcus agalactiae, the ability to adhere to intestinal mucus and growth kinetics. The selected bacteria were identified by 16S rRNA sequencing of and were identified as Exigobacterium sp. I9, Enterococcus faecalis I15 and Myroides odoratimimus I19. Furthermore, the in vivo effect on fish growth was assessed by the addition of selected bacteria to juvenile Oreochromis niloticus feed (106 CFU / g, for 15 days. Survival was also determined after a challenge by intraperitoneal injection of E. tarda (100 μL of 105 UFC / mL. The three selected bacteria increased the specific growth rate, reduced mortality of fish during the experimental challenge with E. tarda and did not cause mortality during the addition in the feed. The positive effects observed in vivo are possibly associated with in vitro activity; however, for biosafety reasons, it is recommended that further studies of Exigobacterium sp. I9 and E. faecalis I15 may be carried out since this genus have been reported of as causative agents of fish mortality, whereas in the case of M. odoratimimus I19, verification of positive effects at a higher production scales is desirable.

  1. Selección masal por peso y coloración en tilapia roja

    Directory of Open Access Journals (Sweden)

    María Alejandra Ruiz Peña

    2009-04-01

    Full Text Available Para evaluar la efectividad de la selección masal por color y peso se analizaron dos generaciones (G1 y G2 de alevinos de tilapia roja Oreochromis sp. De 40.000 larvas a la sexta semana se eliminaron los alevinos manchados y blancos y a las 14 semanas se separaron por sexos. Se midió el peso (g, la longitud total (cm, la altura (cm y el ancho (cm de 150 individuos a las 6, 14 y 24 semanas de edad. En la semana 24 se escogieron 150 machos y 450 hembras con las coloraciones deseables y mayor peso. La selección resultó efectiva para coloración en G2, puesto que la proporción de individuos rojos se incrementó en 15% con respecto a los testigos. Entre generaciones (G1 y G2 el efecto de la selección fue positivo, debido a que la proporción de rojos se incrementó de 64% a 84% y se redujo la de manchados de 31% a 13%. En ambas generaciones los machos fueron significativamente más pesados que las hembras. Se encontraron notables diferencias entre generaciones para peso y talla, puesto que los selectos superaron al control en 27% y 8% (G1 y en 22% y 11% (G2 para el peso y la talla, respectivamente.

  2. Effect of grilling and baking on physicochemical and textural properties of tilapia (Oreochromis niloticus) fish burger.

    Science.gov (United States)

    Bainy, Eduarda Molardi; Bertan, Larissa Canhadas; Corazza, Marcos Lucio; Lenzi, Marcelo Kaminski

    2015-08-01

    The influence of two common cooking methods, grilling and baking, on chemical composition, water retention, fat retention, cooking yield, diameter reduction, expressible water, color and mechanical texture of tilapia (Oreochromis niloticus) fish burgers was investigated. Texture analyses were performed using a Warner-Bratzler test. The fish burger had a softer texture with a lower shear force than other meat products reported in the literature. There were no significant differences in proximate composition, diameter reduction, fat retention and expressible water between the grilled and oven-baked fish burgers. Cooking methods did not affect the cooking times and cooking rates. Warner-Bratzler parameters and color were significantly influenced by the cooking method. Grilling contributed to a shear force and work of shearing increase due to the lower cooking yield and water retention. Raw burgers had the highest L* (69.13 ± 0.96) and lowest b* (17.50 ± 0.75) values. Results indicated that baking yielded a product with better cooking characteristics, such as a desired softer texture with lower shear values (4.01 ± 0.54) and increased water retention (95.82 ± 0.77). Additionally, the baked fish burgers were lighter (higher L*) and less red (lower a*) than the grilled ones.

  3. Storage of vacuum-packaged smoked bologna sausage prepared from Nile tilapia

    Directory of Open Access Journals (Sweden)

    Dayse Aline Ferreira Silva Bartolomeu

    2014-02-01

    Full Text Available Changes in smoked bologna sausage manufactured with Niletilapia (Oreochromis niloticus, and wheat fibers in refrigerated storage (6 ± 2°C during 30 days were evaluated. Minced fish (MF obtained from waste (parings from the filleting fish operations of Nile tilapia (Oreochromis niloticus was used as raw material. In this experiment, were determined Staphylococcus count, the detection of Salmonella sp. (day 0, psychrotrophic count, total and fecal coliforms at45°C, the acceptance sensory test (days 0 and 30, water activity, instrumental color, pH and lipid oxidation analysis (Thiobarbituric acid reactive substances - TBARS days 0, 5, 10, 15, 20, 25 and 30 of storage. Lipid oxidation (TBARS and water activity provided significant differences among storage days. However it was concluded that the bologna sausage remained stable and with acceptable quality for 30 days of storage may be a new alternative to adding value to fish products, because the researched microorganisms had a low count, changes in pH were not significant and sensory test indicated good acceptance of the product during the 30 days of storage.

  4. NUTRITIONAL EVALUATION OF TILAPIA FILLETING WASTE MEAL FOR SWINE IN THE NURSERY PHASE

    Directory of Open Access Journals (Sweden)

    EDSON RICHART

    2016-01-01

    Full Text Available Three experiments were conducted to determine the nutritional composition of tilapia filleting waste meal (TFWM for pigs in the initial phase. In the first experiment, the chemical composition and the values of digestible and metabolizable energy of TFWM were determined using 10 pigs (15.10 ± 0.74 kg, distributed in cages for metabolic research (2 treatments X 5 replicates. The TFWM replaced 20% of the reference diet based on corn and soybean meal. In the second experiment, the ileal digestibility coefficients of amino acids present in TFWM were determined, using chromic oxide as a marker, through the method of sacrifice, using 10 pigs (15.00 ± 0.27 kg, distributed in cages for metabolic research (2 treatments X 5 replicates. Treatments consisted of a basal diet and one without protein. In the third experiment, the performance of pigs fed diets containing different concentrations of TFWM (0, 5, 10, 15 and 20% was evaluated. Forty pigs (15.00 ± 0.87 kg, distributed in pairs in nursery pens (5 treatments X 4 replicates were used. The values of digestible and metabolizable energy corresponded to 3,632 and 3,260 kcal/kg, respectively. Inclusion of up to 10% TFWM in the diet of barrows from 15 to 30 kg did not affect the average daily gain and feed conversion of the animals.

  5. Organochlorine pesticides in lacustrine sediments and tilapias of Metztitlan, Hidalgo, Mexico.

    Science.gov (United States)

    Fernández-Bringas, Laura M; Ponce-Vélez, Guadalupe; Calva, Laura G; Salgado-Ugarte, Isaías Hazamamberth; Botello, Alfonso V; Díaz González, Gilberto

    2008-09-01

    The organochlorine pesticides (OP) are very stable molecules, due to this stability; they are very resistant in the environment and highly related to fat tissues with a wide diffusion property and an average time life higher then 10 years. We studied sediments (November 2001, April and June 2002) and organisms collected in April and July (2002) from the lacustric zone of Metzitlán, Hidalgo, Mexico. The analysis was performed according to UNEP/IAEA (1982) (sediments) and UNEP/FAO/IOC/IAEA (1986) (organisms) methods. Three chemical families of organochlorine pesticides were identified and analyzed to determine posible toxicological risk. The principal organochlorine compounds found in sediments were gamma-HCH, delta-HCH, p,p'-DDT and the endosulfan sulfate; these xenobiotics come from agriculture lands near the river and lake, used intensively, and most probably carried by the rain and rain flows into the main water body. In the tilapias tissue, p,p'-DDD y delta-HCH were detected. The average concentrations of organochlorine pesticides in sediments were within the internacional limits for freshwater benthonic fauna, although lindane (gamma-HCH) was near the limit. The fish were above the criteria established in the local legislation (NOM-027-SSA1-1993 y NOM-028-SSA1-1993).

  6. Genetic parameters and trends of morphometric traits of GIFT tilapia under selection for weight gain

    Directory of Open Access Journals (Sweden)

    Rafael Vilhena Reis Neto

    2014-08-01

    Full Text Available The main factor considered in breeding programs for fish is growth, which can be assessed in terms of a gain in either weight or body measurements. This study was undertaken to evaluate the morphometric traits of GIFT strain tilapia (Oreochromis sp. selected for weight gain. The data set used contained information on 6,650 animals. The genetic values of 8,590 animals in a relationship matrix of five generations were predicted. The following morphometric measurements were evaluated: standard length; body depth and body width. Body area and volume were also calculated. Bi-character analyses involving morphometric traits were used to estimate (covariance components. Heritability, larval and fingerling common environmental effects were estimated for each trait, together with the genetic and phenotypic correlations between traits. Bayesian procedures were utilised by Gibbs chains, and the convergence of the chains was tested using the Heidelberger and Welch method. Genetic trends were estimated by segmented regression of the fish breeding values of the generations considered in this study. Estimates of heritability (0.28 a 0.31 had moderate to high magnitudes for all traits. Genetic correlations between traits were all above 0.8, and the genetic gains were satisfactory from the third generation onwards. From the estimates of the genetic parameters and genetic gain the morphometric traits evaluated have good potential for selection.

  7. Resource recovery from septic tank effluent using duckweed-based tilapia aquaculture.

    Science.gov (United States)

    El-Shafai, Saber A; Abdel-Gawad, Fagr Kh; Samhan, Farag; Nasr, Fayza A

    2013-01-01

    Two parallel duckweed ponds were deployed to utilize nutrients from the effluent of a septic tank treating domestic wastewater. The effluent and fresh biomass of duckweed pond were fed to two subsequent fish ponds stocked with Nile tilapia (Oreochromis niloticus). Fish ponds receiving freshwater and commercial feed were used as control. The results of specific growth rate and feed conversion ratio showed no significant difference between the control ponds and treatment ponds. On the other hand, the total and net fish yields were significantly higher in the control. Microbial analysis revealed contamination of gills, intestine and liver of fish in the treatment ponds. The activity of the immune response genes was up-regulated in the brain and liver of the treatment samples. A micronucleus assay revealed a similar percentage of micronuclei in the polychromatic erythrocytes of blood in the control and treatment samples, while the treatment samples a had higher incidence of micronuclei in the polychromatic erythrocytes of gills, compared with the control.

  8. Isolation of fish skin and bone gelatin from tilapia (Oreochromis niloticus): Response surface approach

    Science.gov (United States)

    Arpi, N.; Fahrizal; Novita, M.

    2018-03-01

    In this study, gelatin from fish collagen, as one of halal sources, was extracted from tilapia (Oreochromis niloticus) skin and bone, by using Response Surface Methodology to optimize gelatin extraction conditions. Concentrations of alkaline NaOH and acid HCl, in the pretreatment process, and temperatures in extraction process were chosen as independent variables, while dependent variables were yield, gel strength, and emulsion activity index (EAI). The result of investigation showed that lower NaOH pretreatment concentrations provided proper pH extraction conditions which combine with higher extraction temperatures resulted in high gelatin yield. However, gelatin emulsion activity index increased proportionally to the decreased in NaOH concentrations and extraction temperatures. No significant effect of the three independent variables on the gelatin gel strength. RSM optimization process resulted in optimum gelatin extraction process conditions using alkaline NaOH concentration of 0.77 N, acid HCl of 0.59 N, and extraction temperature of 66.80 °C. The optimal solution formula had optimization targets of 94.38%.

  9. The antioxidant effects of complexes of tilapia fish skin collagen and different marine oligosaccharides

    Science.gov (United States)

    Ren, Shuwen; Li, Jing; Guan, Huashi

    2010-12-01

    An excess of reactive oxygen species (ROS) leads to a variety of chronic health problems. As potent antioxidants, marine bioactive extracts containing oligosaccharides and peptides have been extensively studied. Recently, there is a growing interest in protein-polysaccharide complexes because of their potential uses in pharmaceutical and food industries. However, only few studies are available on the antioxidant activities of such complexes, in terms of their ROS scavenging capability. In this study, we combined different marine oligosaccharides (isolated and purified) with collagen peptides derived from tilapia fish skin, and evaluated the antioxidant activity of the marine peptide-oligosaccharide complexes vis-à-vis the activity of their original component molecules. Biochemical and cellular assays were performed to measure the scavenging effects on 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide radicals, and to evaluate the influences on the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in UV-induced photoaging models. The results indicated that the antioxidant activities of all the complexes were stronger than those of their individual components. Among the 11 complexes tested, two complexes, namely MA1000+CP and κ-ca3000+CP, turned out to be highly effective antioxidants. Although the detailed mechanisms of this improved scavenging ability are not fully understood, this work provides insights into the design of highly efficient peptide-oligosaccharide complexes for potential applications in pharmaceutical, cosmetics and food industries.

  10. Assessment of benthic macroinvertebrates at Nile tilapia production using artificial substrate samplers

    Directory of Open Access Journals (Sweden)

    M. S. G. Moura e Silva

    Full Text Available Abstract Biomonitoring is a cheap and effective tool for evaluation of water quality, and infer on the balance of aquatic ecosystems. The benthic macroinvertebrates are bioindicators sensitive to environmental changes, and can assist in detecting and preventing impacts such as organic enrichment and imbalance in the food chain. We compared the structure of benthic communities on artificial substrate samplers located in places near and far from net cages for production of Nile tilapia (Oreochromis niloticus. Samplers were manufactured with nylon net, using substrates such as crushed stone, gravel, loofah and cattail leaves. Samples were collected after 30 days of colonization, rinsed and then the specimens were identified and quantified. The following metrics were calculated: richness of Operational Taxonomic Units, Margalef richness, abundance of individuals, Shannon index and evenness index. The macrobenthic community structure was strongly modified according to the proximity of the net cages. Metrics showed significant differences (p < 0.05 between near and distant sites, for both periods (dry and rainy seasons. The position of the samplers significantly affected the structure of macroinvertebrate community, as near sites showed higher values for the community metrics, such as richness and diversity. Near sites presented a larger number of individuals, observed both in the dry and rainy seasons, with a predominance of Chironomidae (Diptera in the dry season and Tubificidae (Oligochaeta in the rainy season.

  11. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster.

    Science.gov (United States)

    Velázquez-Abunader, Iván; Gómez-Muñoz, Victor Manuel; Salas, Silvia; Ruiz-Velazco, Javier M J

    2015-09-01

    Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus), red octopus (Octopus maya) and the Caribbean spiny lobster (Panulirus argus). The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed.

  12. Inhibition of fish bacteria pathogen in tilapia using a concoction three of Borneo plant extracts

    Science.gov (United States)

    Hardi, EH; Saptiani, G.; Kusuma, IW; Suwinarti, W.; Sudaryono, A.

    2018-04-01

    This study was conducted to evaluate the antibacterial activity of concoction Solanum ferox, Boesenbergia pandurata and Zingimber zerumbetextract (SF, BP, and ZZ) to inhibit pathogenic bacteria in tilapia with the each concentrations 600 ppm BP, 900 ppm SF and 200 ppm ZZ. Antibacterial activity was measured by testing the concoction of three plants extract against single isolate Aeromonas hydrophila and Pseudomonas sp. and combined both bacteria (105 colony-forming units per milliliter). In this research, oxytetracycline was used as a control. Clear zone inhibition was observed at 6, 12, 18 and 24 hours after incubation at 30 °C. The results showed that the different concoction of BP: SF: ZZ have inhibitory zones against both single and joint isolate bacteria. The ratio of3:3:4 and 1:8:1 had higher antibacterial activity towards Pseudomonas sp. and 1:1:3 ratios both inhibit joint bacteria. The ZI% higher of concoction extracts against A.hydrophila is 1:1:8; 1:3:1; 3:4:3. The ZI% concoction extracts against Pseudomonas sp. ware 3:3:4 and 1:8:1 ratio. While the two bacteria combined, just 1:1:3 ratio had higher Z%. The conclusion is that a concoction of SF:BP:ZZ is effective to inhibit the growth of A.hydrophila and Pseudomonas sp., even its antibacterial ability is similar to the effectiveness of antibiotic oxytetracycline.

  13. Effect of sex on the fillet quality of Nile tilapia fed varying lipid sources

    Directory of Open Access Journals (Sweden)

    Tamás Molnár

    2010-01-01

    Full Text Available Effect of sex and three different oil supplementations on main production traits, and fatty acid composition of the fillet and gonads was investigated in Nile tilapia. Males and females had significantly different final weights owing to the occasional reproduction of fish. Diets had no significant effects on the main production traits. The percentage of ALA in the fillet was significantly higher in the males in all diets. Significant differences were found between the two sexes in the n-3 PUFA, resulting in a higher n-3/ n-6 ratio in the males. MUFA and n-6 PUFA percentages and EPA/DHA ratio in the fillet were affected by the fat sources in the diet. The proportion of the main fatty acids showed significant changes in the gonads. Both sex and the diet had a significant effect on LA, AA, and DHA percentages. In case of EPA the males had significantly higher values than the females. ALA was affected by the different diets, the fillets of the LO group containing the highest percentage Regarding the main FA groups, n-3 PUFA, n-6 PUFA, n-3/n-6 ratio and the DHA/EPA ratio were affected by sex and diets.

  14. Effects of transportation stress on quality and sensory profiles of Nile tilapia fillets

    Directory of Open Access Journals (Sweden)

    Elenice Souza dos Reis Goes

    Full Text Available ABSTRACT: This study evaluated pre-slaughter stress and its influence on the stress indicators, quality characteristics and sensory characteristics of Nile tilapia fillets. To this end, two experiments were conducted: (1 two transportation times (60 and 240 min, with a density of 200 kg m−3, were compared to control treatment fish (in which the fish were removed from the net cage and immediately euthanized; and (2 two transportation densities (100 and 400 kg m−3, transported for 180 min, compared with control treatment fish. In experiment 1, the transportation time of 60 min resulted in higher levels of serum cortisol and plasma glucose compared to the transportation time of 240 min and the control. Fish fillets transported for 240 min had higher water-holding capacity, less water loss by pressure and higher levels of juiciness compared to fish transported for 60 min. Color, pH and water loss during cooking were not affected by transportation time. In experiment 2, transportation densities of 100 and 400 kg m−3 did not significantly affect the stress indicators nor the instrumental quality parameters of the fillets, but fish transported at 400 kg m−3 showed better visual acceptance by panellists.

  15. Monosensitivity to pangasius and tilapia caused by allergens other than parvalbumin.

    Science.gov (United States)

    Ebo, D G; Kuehn, A; Bridts, C H; Hilger, C; Hentges, F; Stevens, W J

    2010-01-01

    Fish allergy is one of the most common food allergies in populations where fish is a major part of the diet. Most fish-allergic patients react to the panallergen parvalbumin present in multiple fish species. Our aim was to investigate the clinical case of a patient with oral allergy syndrome to pangasius and Nile tilapia but tolerance of other fish and seafood. The temporal relationship between fish consumption and allergic symptoms, the positive skin prick tests, and the basophil activation test results for both fish species strongly supported the diagnosis of an immunoglobulin (Ig) E-mediated allergy. This was confirmed by the detection of specific IgE to 18-kDa and 45-kDa proteins in immunoblot analysis. Notably, the patient was not sensitized to parvalbumin, as shown by enzyme-linked immunosorbent assay using purified allergens. Cross-reactivity between fish species can result from sensitization to allergens other than parvalbumin. This case report emphasizes the applications of flow cytometry-assisted analysis in the diagnosis of food allergy.

  16. Interactive effects of genotype x environment on the live weight of GIFT Nile tilapias.

    Science.gov (United States)

    Oliveira, Sheila N DE; Ribeiro, Ricardo P; Oliveira, Carlos A L DE; Alexandre, Luiz; Oliveira, Aline M S; Lopera-Barrero, Nelson M; Santander, Victor F A; Santana, Renan A C

    2017-01-01

    In this paper, the existence of a genotype x environment interaction for the average daily weight in GIFT Nile tilapia (Oreochromis niloticus) in different regions in the state of Paraná (Brazil) was analyzed. The heritability results were high in the uni-characteristic analysis: 0.71, 0.72 and 0.67 for the cities of Palotina (PL), Floriano (FL) and Diamond North (DN), respectively. Genetic correlations estimated in bivariate analyzes were weak with values between 0.12 for PL-FL, 0.06 for PL and 0.23 for DN-FL-DN. The Spearman correlation values were low, which indicated a change in ranking in the selection of animals in different environments in the study. There was heterogeneity in the phenotypic variance among the three regions and heterogeneity in the residual variance between PL and DN. The direct genetic gain was greater for the region with a DN value gain of 198.24 g/generation, followed by FL (98.73 g/generation) and finally PL (98.73 g/generation). The indirect genetic gains were lower than 0.37 and greater than 0.02 g/generation. The evidence of the genotype x environment interaction was verified, which indicated the phenotypic heterogeneity of the variances among the three regions, weak genetic correlation and modified rankings in the different environments.

  17. Preparation and bioavailability of calcium-chelating peptide complex from tilapia skin hydrolysates.

    Science.gov (United States)

    Chen, Jun; Qiu, Xujian; Hao, Gengxin; Zhang, Meng; Weng, Wuyin

    2017-11-01

    With the continuous improvement in material life, the generation of fish by-products and the market demand for calcium supplements have been increasing in China. Therefore a calcium-chelating peptide complex (CPC) from tilapia skins was prepared and its effect on calcium (Ca)-deficient mice was investigated. The molecular weight distribution of CPC mainly ranged from 2000 to 180 Da, and its contents of complete amino acids and free amino acids were 85.30 and 8.67% (w/w) respectively. Scanning electron microscopy images and Fourier transform infrared data revealed that Ca crystals were bound with gelatin hydrolysates via interaction between Ca ions and NH/CN groups. When Ca-deficient mice were fed CPC and CaCO 3 respectively for 4 weeks, no significant differences in serum biochemistry or bone mineral density were found. However, the length, weight, Ca content and hydroxyproline content of the femur, Ca absorption and body weight gain of mice fed CPC were significantly higher than those of mice fed CaCO 3 . It is concluded that the prepared CPC could promote bone formation via better bioavailability of Ca and an increase in bone collagen. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Ectoparasites of Nile tilapia (Oreochromis niloticus in cage farming in a hydroelectric reservoir in Brazil

    Directory of Open Access Journals (Sweden)

    Aline Cristina Zago

    Full Text Available For this study, we performed a parasitological analysis of cage-cultured Nile tilapia (Oreochromis niloticus from the Água Vermelha Reservoir, Southeastern Brazil, and verified relationships with limnological data, seasonality, and fish growth phase. From March 2010 to March 2011, sixty-three specimens of O. niloticusin three growth phases (i.e., initial, intermediate, and final were collected. All fish specimens were infested with at least one ectoparasite species (prevalence = 100%. Five species of protozoans (Trichodina compacta, Trichodina magna, Ichthyophthirius multifiliis,Piscinoodinium pillulare, and Epistylissp. and five species of monogenoids (Cichlidogyrus halli, Cichlidogyrus thurstonae,Cichlidogyrus sp. 1, Scutogyrus longicornis, and Gyrodactylus sp. were observed. The abundance of Trichodina spp. and the prevalence of Epistylis sp. were higher in the dry season, and the prevalence of C. halli was higher in the rainy season. For the majority of ectoparasites found in this study, fish in the intermediate and final phases had higher parasitism rates than those in the initial phase. The data presented may help fish farmers to understand the parasite dynamics of the fish species studied in cage-farming systems.

  19. Ectoparasites of Nile tilapia (Oreochromis niloticus) in cage farming in a hydroelectric reservoir in Brazil.

    Science.gov (United States)

    Zago, Aline Cristina; Franceschini, Lidiane; Garcia, Fabiana; Schalch, Sérgio Henrique Canello; Gozi, Kátia Suemi; Silva, Reinaldo José da

    2014-01-01

    For this study, we performed a parasitological analysis of cage-cultured Nile tilapia (Oreochromis niloticus) from the Água Vermelha Reservoir, Southeastern Brazil, and verified relationships with limnological data, seasonality, and fish growth phase. From March 2010 to March 2011, sixty-three specimens of O. niloticus in three growth phases (i.e., initial, intermediate, and final) were collected. All fish specimens were infested with at least one ectoparasite species (prevalence = 100%). Five species of protozoans (Trichodina compacta, Trichodina magna, Ichthyophthirius multifiliis, Piscinoodinium pillulare, and Epistylis sp.) and five species of monogenoids (Cichlidogyrus halli, Cichlidogyrus thurstonae, Cichlidogyrus sp. 1, Scutogyrus longicornis, and Gyrodactylus sp.) were observed. The abundance of Trichodina spp. and the prevalence of Epistylis sp. were higher in the dry season, and the prevalence of C. halli was higher in the rainy season. For the majority of ectoparasites found in this study, fish in the intermediate and final phases had higher parasitism rates than those in the initial phase. The data presented may help fish farmers to understand the parasite dynamics of the fish species studied in cage-farming systems.

  20. Effect of brining on the drying rate of tilapia in a solar tunnel dryer

    Energy Technology Data Exchange (ETDEWEB)

    Kituu, G.M.; Shitanda, D.; Kanali, C.L.; Mailutha, J.T. [Jomo Kenyatta Univ. of Agriculture and Technology, Nairobi (Kenya). BEED

    2008-07-01

    In addition to being a source of protein, fish is an important source of local and foreign currency earnings in Kenya. A substantial amount of fish production is exported. Approximately 30 per cent is exported to the European Union, the United States, and countries in the Middle East, but nearly half of the total annual fish harvest in Kenya goes to waste due to poor processing and preservation. Measures must be taken to ensure the fish industry is protected and waste is minimized, since the livelihood of over 500,000 people depends on fish as a source of proteins and employment. Therefore, it is necessary to implement appropriate and affordable processing and preservation techniques for fish at the artisanal landing sites in order to reduce the wastage and spoilage of fish during oversupply, and to enhance long storage. This paper presented studies that were conducted to determine the effect of brining on the drying rate of tilapia in a solar tunnel dryer. The paper discussed the materials and methods, including a description of the solar tunnel dryer system; the brining process of fish; the fish drying process; and data analysis. It was concluded that limiting the amount of salt used in brining, and subsequently dehydrating fish with a solar tunnel dryer achieves a more stable and suitable dried fish product than osmotic dehydration or solar drying process separately. 19 refs., 5 figs., 2 appendices.

  1. Dietary Lactobacillus plantarum supplementation enhances growth performance and alleviates aluminum toxicity in tilapia.

    Science.gov (United States)

    Yu, Leilei; Zhai, Qixiao; Zhu, Jiamin; Zhang, Chengcheng; Li, Tianqi; Liu, Xiaoming; Zhao, Jianxin; Zhang, Hao; Tian, Fengwei; Chen, Wei

    2017-09-01

    We investigated the protection offered by the probiotic Lactobacillus plantarum CCFM639 against waterborne Al exposure in tilapia. Fish were allocated to control, CCFM639-only, Al-only or Al plus CCFM639 groups. The fish were exposed to 2.73mg/L Al ions for 4 weeks. The probiotic was incorporated into the fish diet at 10 8 CFU/g and provided twice daily. Our results showed that L. plantarum CCFM639 significantly enhanced feed utilization, growth performance and antioxidant ability in the absence of waterborne Al exposure. When fish were exposed to Al, dietary supplementation with the strain effectively decreased the death rate and accumulation of Al in tissues, and enhanced growth performance. Moreover, Al-induced changes in hematobiochemical parameters and hepatic oxidative stress and histopathology were also alleviated. Therefore, L. plantarum CCFM639 may be a novel dietary supplement for fish to enhance growth performance and prevent aquaculture and food safety problems induced by Al pollution. Copyright © 2017. Published by Elsevier Inc.

  2. The effects of tritiated water on some developmental stages of tilapia nilotica

    International Nuclear Information System (INIS)

    Carino, V.S.

    1986-01-01

    Seven developmental stages of Tilapia nilotica from gastrula (11 hr) to the active feeding and free swimming stage (10-d) were reared in tritiated water of concentrations 10 -3 10 -2 and 10 -1 Ci 1 -1 . The fish were reared for different lengths of time, the first group for the period till the next developmental stage and the second group till 3 weeks of age or day 21. Treated and control specimens were compared. An over-all delay in development was noted both at the gross morphological and the histological levels in the experimental fish. Growth was stunted. Many had unresorped yolk which was observable externally in the distended abdomens and histologically within the liver. Percent survival was lower in the treated fish and this was, in general, inversely related to developmental stage and tritium concentration of the rearing water. Posthatch larvae were sluggish to inactive. The liver exhibited histological aberrations which include the presence of adipose cells in place of liver parenchyma in the more anterior liver regions. Brains of treated fish, in general were smaller. One instance of an abnormal brain growth and findings on the retinal epithelium, spleen and pancreas are described. Development of gonads and digestive tract was, in general, retarded. (Auth.) 40 refs.; 5 tabs

  3. Effect of X-rays on the mitotic frequency in the fish Tilapia mossambica

    International Nuclear Information System (INIS)

    Manna, G.K.; Som, R.C.

    1977-01-01

    Male and female Tilapia mossambica were irradiated by X-rays with a dose of 100 r. The mitotic frequency in 4,000 cells from their kidney was determined at each of 10 intervals between 1 hour and 120 hour. In irradiated males the frequency of dividing cells was 3.12% at 1 hour, 2.55% at 2 hour, 2.07% at 3 hour, 2.02% at 6 hour, 1.25% at 18 hours, 2.05% at 24 hour, 2.60% at 48 hour, 3.37% at 72 hour, 3.77% at 96 hour and 3.87% at 120 hour while in the irradiated females at the above intervals the frequencies were 5.62%, 3.25%, 2.35%, 2.50%, 2.00%, 5.00%, 6.00%, 6.67% and 6.77% respectively. In the normal individuals the frequency of dividing cells was 4.25% in males and 7.50% in females. The data of the normal and treated series have been analysed and the time factor, sex factors etc., on the inhibitory effect of ionizing radiations in kidney cells of the fish have been discussed. (author)

  4. Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.)

    Science.gov (United States)

    El Gamal, A.-R.A.; Davis, K.B.; Jenkins, J.A.; Les, Torrans E.

    1999-01-01

    Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus, was investigated by heat shock, cold shock, hydrostatic pressure, and/ or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C. Heat shock of 40-41 C at 4-6 min after fertilization was effective in inducing up to 100% triploidy with hatchability similar to controls. Cold shock at 13 C for 45 min five min after fertilization induced 85-100% triploids. Heat shock and multiple heat shocking were the most effective treatments for the induction of tetraploidy. Two heat treatments of 41 C applied at 65 and 80 min after fertilization for 5 min each produced approximately 80% tetraploidy in hatched fry. Immersion of fertilized eggs in cytochalasin A, B, or D at concentrations up to 10 ??g/L applied at various times and durations was ineffective in inducing triploidy or tetraploidy.

  5. Effect of Poly Aluminium Chloride (PAC) on some blood constituents of Nile Tilapia (Oreochromis niloticus)

    International Nuclear Information System (INIS)

    Adam, H. M.; Agab, H.

    2006-01-01

    Poly aluminium chloride (PAC) is an urban drinking water purification substance that was introduced recently in Sudan and used to substitute polymer poly diallyl dimethyl aluminium chloride (DADMAC) and aluminium sulphate in water purification treatments. This study was conducted to determine its effects on fish health, which is is considered a biological indicator and an essential component of fresh water ecosystem. In this experiment, PAC was used in three different concentrations (0.1, 0.2 and 0.3 ml/1) in experimental tanks to achieve the desirable doses for the study. The tanks were populated by Nile Tilapia fingerlings (Oreochromis niloticus) with an average weight ranging between 70 and 100 grams. Exposure of this fish to PAC resulted in an immediate signification reduction (P<0.01) in haemoglobin concentration, erythrocytes count, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin concentration of experimental fingerlings blood. The degree of reduction in these parameters was directly proportional to the concentration of PAC used. (Author)

  6. Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus)

    Science.gov (United States)

    Chapman, Robert W.; Somerville, Stephen E.; Guillette, Matthew P.; Botha, Hannes; Hoffman, Andre; Luus-Powell, Wilmien J.; Smit, Willem J.; Lebepe, Jeffrey; Myburgh, Jan; Govender, Danny; Tucker, Jonathan; Boggs, Ashley S. P.

    2016-01-01

    One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various “outbreaks” of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River. PMID:27115488

  7. The influence of chromatic background on the photosensitivity of tilapia erythrophores

    Directory of Open Access Journals (Sweden)

    Shyh-Chi Chen

    2014-01-01

    Non-mammalian vertebrates and invertebrates use extraretinal photoreceptors to detect light and perform diverse non-image-forming functions. Compared to well-studied visual systems, the effect of ambient light conditions on photosensory systems of extraretinal photoreceptors is poorly understood. Chromatophores are photosensitive dermal pigment cells that play an important role in the formation of body color patterns to fit the surrounding environment. Here, we used tilapia erythrophores to investigate the relationship between environmental light and chromatophore photoresponses. All erythrophores from three spectral conditions aggregated their pigment granules in UV/short wavelengths and dispersed in middle/long wavelengths. Unlike retinal visual systems, environmental light did not change the usage of the primary opsins responsible for aggregation and dispersion. In addition, short wavelength-rich and red-shifted background conditions led to an inhibitory effect on erythrophore photoresponses. We suggest that, as extraretinal photoreceptors for non-image-forming functions, chromatophores directly adjust their photoresponse sensitivity via changes in opsin expression levels rather than opsin types when environmental light changes.

  8. Organochlorine pesticides in lacustrine sediments and tilapias of Metztitlan, Hidalgo, Mexico

    International Nuclear Information System (INIS)

    Fernandez-Bringas, Laura M.; Ponce-Velez, Guadalupe; Botello, Alfonso V.; Calva B, Laura G.; Salgado-Ugarte, Isaias Hazamamberth; Diaz Gonzalez, Gilberto

    2008-01-01

    The organochlorine pesticides (OP) are very stable molecules, due to this stability; they are very resistant in the environment and highly related to fat tissues with a wide diffusion property and an average time life higher than 10 years. Sediments were studied in November 2001, April and June 2002 and organisms collected in April and July 2002, from the lacustric zone of Metzitlan, Hidalgo, Mexico. The analysis was performed according to UNEP/IAEA (1982) (sediments) and UNEP/FAO/IOC/IAEA (1986) (organisms) methods. Three chemical families of organochlorine pesticides were identified and analyzed to determine possible toxicological risk. The principal organochlorine compounds found in sediments were γ-HCH, δ-HCH, p,p'-DDT and the endosulfan sulfate; these xenobiotics come from agriculture lands near the river and lake, used intensively, and most probably carried by the rain and rain flows into the main water body. The p,p'-DDD and δ-HCH were detected in the tilapias tissue. The average concentrations of organochlorine pesticides in sediments were within the international limits for freshwater benthic fauna, although lindane, γ-HCH, was near the limit. The fish was above the criteria established in the local legislation (NOM-027-SSA1-1993 y NOM-028-SSA1-1993). (author)

  9. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster

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    Iván Velázquez-Abunader

    2015-09-01

    Full Text Available Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus,red octopus (Octopus mayaand the Caribbean spiny lobster (Panulirus argus.The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed.

  10. Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus.

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    John A Bowden

    Full Text Available One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various "outbreaks" of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin, in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River.

  11. Magadi tilapia ecological specialization: filling the early gap in the speciation continuum.

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    Pinho, Catarina; Faria, Rui

    2016-04-01

    Cichlid fish are well known for their high speciation rates, which are usually accompanied by spectacular and rapid diversification in eco-morphological and secondary sexual traits. This is best illustrated by the famous repeated explosive radiations in the African Great Lakes Tanganyika, Malawi and Victoria, each lake harbouring several hundreds of mostly endemic species. Correspondingly, cichlids diversified very rapidly in many other lakes across their range. Although the larger radiations, unparalleled in vertebrates, are certainly the most intriguing, they are also the most intricate and difficult to address because of their complex nature. This is where smaller, simpler systems may prove to be the most useful. In this issue of Molecular Ecology, Kavembe et al. (2016) report very recent genetic diversification accompanied by ecological specialization in cichlids of the small and ecologically extreme Lake Magadi, in Kenya. Combining geometric morphometrics, stable isotope analysis, population genomics using RADSeq data and coalescent-based modelling techniques, the authors characterize the eco-morphological differences between genetically distinct populations of Magadi tilapia (Alcolapia grahami), which are consistent with the different environmental conditions they experience, and infer their history of divergence. The simplicity of the focal system and the use of a multidisciplinary approach make this work particularly important for our understanding of the early stages of speciation, in both cichlids and other organisms. © 2016 John Wiley & Sons Ltd.

  12. Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers

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    H. M. R. Abdel-Latif

    2017-08-01

    Full Text Available Background: Toxic cyanobacterial blooms (Microcystis aeruginosa contains microcystins [MCs] have been reported to induce clinicopathological alterations as well as different oxidative stress in aquatic biota. Aim: Three-week subchronic exposure experiment was carried out on Nile tilapia, to determine their effects on fish behavior, tissues, liver functions, antioxidant enzymes, and lipid peroxidation. Materials and Methods: Fish were exposed to four main treatments; orally fed diet plus toxic cells of M. aeruginosa (containing 3500 μg/g MC-LR, immersion in 500 μg MC-LR/L, intraperitoneal injection of M. aeruginosa MC-LR with a dose of 0.1 ml of extracted toxin at a dose of 200 μg/kg bwt, and the fourth one served as a control group, then the fish were sacrificed at the end of 3rd week of exposure. Results: The results revealed no recorded mortality with obvious behavioral changes and an enlarged liver with the congested gall bladder. Histopathology demonstrated fragmentation, hyalinization, and necrosis of the subcutaneous musculature marked fatty degeneration, and vacuolation of hepatopancreatic cells with adhesion of the secondary gill lamellae associated with severe leukocytic infiltration. Furthermore, liver functions enzymes (aspartate aminotransferase and alanine aminotransferase, and the activities of glutathione peroxidase, glutathione reductase, lipid peroxidase, and catalase enzymes were significantly increased in all treatments starting from the 2nd week as compared to the control levels. Conclusion: In this context, the study addresses the possible toxicological impacts of toxic M. aeruginosa contain MC-LR to Nile tilapia, and the results investigated that MC-LR is toxic to Nile tilapia in different routes of exposure as well as different doses.

  13. Vitamin C modulates cadmium-induced hepatic antioxidants' gene transcripts and toxicopathic changes in Nile tilapia, Oreochromis niloticus.

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    El-Sayed, Yasser S; El-Gazzar, Ahmed M; El-Nahas, Abeer F; Ashry, Khaled M

    2016-01-01

    Cadmium (Cd) is one of the naturally occurring heavy metals having adverse effects, while vitamin C (L-ascorbic acid) is an essential micronutrient for fish, which can attenuate tissue damage owing to its chain-breaking antioxidant and free radical scavenger properties. The adult Nile tilapia fish were exposed to Cd at 5 mg/l with and without vitamin C (500 mg/kg diet) for 45 days in addition to negative and positive controls fed with the basal diet and basal diet supplemented with vitamin C, respectively. Hepatic relative mRNA expression of genes involved in antioxidant function, metallothionein (MT), glutathione S-transferase (GST-α1), and glutathione peroxidase (GPx1), was assessed using real-time reverse transcription polymerase chain reaction (RT-PCR). Hepatic architecture was also histopathologically examined. Tilapia exposed to Cd exhibited upregulated antioxidants' gene transcript levels, GST-⍺1, GPx1, and MT by 6.10-, 4.60-, and 4.29-fold, respectively. Histopathologically, Cd caused severe hepatic changes of multifocal hepatocellular and pancreatic acinar necrosis, and lytic hepatocytes infiltrated with eosinophilic granular cells. Co-treatment of Cd-exposed fish with vitamin C overexpressed antioxidant enzyme-related genes, GST-⍺1 (16.26-fold) and GPx1 (18.68-fold), and maintained the expression of MT gene close to control (1.07-fold), averting the toxicopathic lesions induced by Cd. These results suggested that vitamin C has the potential to protect Nile tilapia from Cd hepatotoxicity via sustaining hepatic antioxidants' genes transcripts and normal histoarchitecture.

  14. Nutrient retention capabilities of Nile tilapia ( Oreochromis niloticus) fed bio-regenerative life support system (BLSS) waste residues

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    Gonzales, John M.; Brown, Paul B.

    Nile tilapia were evaluated as a bio-regenerative sub-process for reducing solid waste potentially encountered in bio-regenerative life support systems. Ten juvenile Nile tilapia (mean weight = 2.05 g) were stocked into triplicate aquaria and fed one of seven experimental diets consisting of vegetable, bacterial, or food waste for a period of seven weeks. Weight gain (g), specific growth rate (mg/d), and daily consumption (g) was significantly higher ( p diet (37.99 and 68.54, respectively) followed by fish fed the wheat bran/wheat germ diet (23.19 and 63.67, respectively). Nitrogen, sulfur, and crude protein retention was significantly higher ( p diet (23.68, 21.89, and 23.68, respectively). A general loss of minerals was observed among all groups. Strong associations were observed between crude lipid retention and sulfur retention ( r2 = 0.94), crude lipid retention and carbon retention ( r2 = 0.92), WG and fiber content of dietary treatments ( r2 = 0.92), WG and carbon retention and ( r2 = 0.88), WG and lysine content of waste residues ( r2 = 0.86), crude protein retention and carbon retention ( r2 = 0.84), sulfur retention and crude protein retention ( r2 = 0.84), and total sulfur amino acid (TSAA) content of residues and WG ( r2 = 0.81). Weaker associations existed between WG and crude lipid retention ( r2 = 0.77), crude fiber content and carbon retention ( r2 = 0.76), and WG and methionine content of waste residues ( r2 = 0.75). Additional research is needed to improve the nutritional quality of fibrous residues as a means to improve tilapia's ability to utilize these residues as a food source in bio-regenerative support systems.

  15. Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae in the Aguamilpa Reservoir, Mexico

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    Emilio Peña Messina

    2010-12-01

    Full Text Available Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2 413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL and total weight (TW were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L ∞, k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b<3. Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L∞=43.33cm standard length, k=0.36/year and t0=-0.43years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species. Rev. Biol. Trop. 58 (4: 1577-1586. Epub 2010 December 01.

  16. Histologic structure of red nile tilapia fish (Oreochromis nilloticus Var.) gill which is exposed to lead acetate

    Science.gov (United States)

    Utami, N. R.; Widiyaningrum, P.; Iswari, R. S.

    2018-03-01

    Fish is a water biota commonly used as the bioindicator of water pollution level. One of the animals which are recommended by EPA as the test species is red Nile Tilapia fish (Oreochromis niloticus var). The purpose of this research is to get the value of LC50-96 hours in the toxicity test toward the fishes which are exposed to lead acetate with some details identification of the gills damage by gill histologic structure examination together with the determination of the lead concentration which caused the destruction. Sixty fish were used in the preliminary test to detect the threshold concentration (LC0-48 h); whereas 120 fish were used in the toxicity test to get the mortality level of fish up to 50% in 96 h. Finally, for treatment test, there were 80 fish which were exposed to lead acetate in the concentration of 0 ppm, 259.51 ppm, 291.94 ppm and 324.38 ppm. All the treatment tests were given for four weeks. The data were collected at the end of the 4th week, and then, the description of the fish gill histology structure was done. The histology observation of the fishes gill detected some damages in the form of edema (0% -25%), lamellar fusion (1% -75%), hyperplasia (0% -50%), epithelial lifting (0% -50%), and necrosis (0% -50%). The results indicate that administration of lead acetate accelerates moderate damage to the red Nile tilapia fish gill structure. The greatest level of damage is lamellar fusion, while the other decline damages are edema, hyperplasia, epithelial lifting, and necrosis. Furthermore, it can be concluded that LC50-96 hours value in the lead acetate toxicity test of red Nile tilapia fish is 324,38 ppm with some histologic structure damage in the gill the fishes.

  17. Determination of cyanuric acid residues in catfish, trout, tilapia, salmon and shrimp by liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    Karbiwnyk, Christine M.; Andersen, Wendy C.; Turnipseed, Sherri B.; Storey, Joseph M.; Madson, Mark R.; Miller, Keith E.; Gieseker, Charles M.; Miller, Ron A.; Rummel, Nathan G.; Reimschuessel, Renate

    2009-01-01

    In May 2007, investigators discovered that waste material from the pet food manufacturing process contaminated with melamine (MEL) and/or cyanuric acid (CYA) had been added to hog and chicken feeds. At this time, investigators also learned that adulterated wheat gluten had been used in the manufacture of aquaculture feeds. Concern that the contaminated feed had been used in aquaculture and could enter the human food supply prompted the development of a method for the determination of CYA residues in the edible tissues of fish and shrimp. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed as a sensitive technique for the analysis of CYA in catfish, tilapia, salmon, trout and shrimp tissue. CYA was extracted from ground fish or shrimp with an acetic acid solution, defatted with hexane, and isolated with a graphitic carbon black solid-phase extraction column. Residues were separated from matrix components using a porous graphitic carbon LC column, and then analyzed with electrospray ionization in negative ion mode on a triple quadrupole mass spectrometer. Selective reaction monitoring was performed on the [M-H] - m/z 128 ion resulting in the product ions m/z 85 and 42. Recoveries from catfish, tilapia and trout fortified with 10-100 μg kg -1 of CYA averaged 67% with a relative standard deviation (R.S.D.) of 18% (n = 107). The average method detection limit (MDL) for catfish, tilapia and trout is 3.5 μg kg -1 . An internal standard, 13 C 3 -labeled CYA, was used in the salmon and shrimp extractions. Average recovery of CYA from salmon was 91% (R.S.D. = 15%, n = 18) with an MDL of 7.4 μg kg -1 . Average recovery of CYA from shrimp was 85% (R.S.D. = 10%, n = 13) with an MDL of 3.5 μg kg -1

  18. Physicochemical analysis of frankfurter type sausages made with red tilapia fillet waste (Oreochromis sp and quinoa flour (Chenopodium quinoa W.

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    José Igor Hleap Zapata

    2017-10-01

    Full Text Available Abstract In Colombia, the production of red tilapia (Oreochromis sp has shown important development in recent years. It is a hydro-biological resource that generates fish fillet waste that can be used in the manufacture of fish products. The aim of this research was to analyze the influence of quinoa flour on the physicochemical properties, texture and oxidative stability during storage and sale of Frankfurter sausages made with red tilapia fillet waste when adding two concentrations of quinoa flour, 10 g/kg and 20 g/kg, and a control treatment with no quinoa flour. The sausages were vacuum packed and stored under refrigeration (2 °C ± 2 °C. The proximate chemical composition, pH, CIElab coordinates, lipid oxidation, water holding capacity, water binding ability and cooking yield were determined, along with an instrumental texture analysis for each of the sausages prepared. The addition of quinoa flour at a concentration of 10 g/kg presented the best water holding capacity, water binding ability, lighter coloration and cooking yield, as compared to the control sausage. By contrast, the sausages with 20 g/kg were harder and required greater effort to cut than the control (p < 0.05. The addition of quinoa flour increased fat oxidation after 6 days of monitoring. The addition of 10 g/kg of quinoa flour was the best concentration for the production of sausages made with red tilapia fillet waste, which represents a new alternative for hydro-biological-origin foodstuffs.

  19. Effect of the establishment of dominance relationships on cortisol and other metabolic parameters in Nile tilapia (Oreochromis niloticus

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    Corrêa S.A.

    2003-01-01

    Full Text Available The objective of the present study was to investigate the influence of the establishment of dominance relationships and social stress on plasma cortisol and metabolite levels in Nile tilapia (Oreochromis niloticus. During the 30-day experiment, the fish weighing 236 ± 29 g were kept in individual aquaria, except for two pairings lasting 6 h each. Blood samples were taken from the animals before and after pairing. Display, approach, attack, rebuff, chase flight, and coloration were carried out on days 16 and 30. Activities and behaviors characteristic of the establishment of dominance relationships were described. It was possible to classify all experimental fish (N = 30 as dominant or subordinate. No differences were detected between dominant (N = 15 and subordinate (N = 15 fish during isolation or after pairing in cortisol (isolated: 5.76 ± 0.98 vs 5.42 ± 0.63; paired: 10.94 ± 1.62 vs 11.21 ± 2.45 µg/dl, glucose (isolated: 60.02 ± 4.9 vs 67.85 ± 16.16; paired: 110.44 ± 15.72 vs 136.26 ± 22.46 mg/dl, triglyceride (isolated: 167.87 ± 5.06 vs 185.68 ± 7.24; paired: 210.85 ± 13.40 vs 221.82 ± 12.70 mg/dl or total protein levels (isolated: 7.01 ± 0.42 vs 6.69 ± 0.59; paired: 9.21 ± 0.62 vs 9.51 ± 0.66 g/dl. However, when isolated (N = 30 and paired (N = 30 tilapia were compared, there were significant differences in cortisol and metabolite levels. The similar response presented by dominant and subordinate tilapia indicates that establishment of dominance relationships was a stressor for both groups.

  20. The Efficacy of Nile Tilapia (Oreochromis niloticus Broodstock and Larval Immunization against Streptococcus agalactiae and Aeromonas hydrophila

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    Wesly Pasaribu

    2018-03-01

    Full Text Available Streptococcus agalactiae and Aeromonas hydrophila have been recognized as the causative agents of mortality in tilapia larvae with single infection and coinfection. The objective of this study was to evaluate the efficacy of maternal transfer and offspring protection from the immunization of monovalent and bivalent vaccines on Nile tilapia (Oreochromis niloticus broodstock and larval immunization. Four groups of broodstock were intraperitoneally injected with formalin killed whole-cells of S. agalactiae (Sa group, A. hydrophila (Ah group, the bivalent mixed vaccine of them (Biv group, and phosphate-buffered saline as a control (Pbs group. Immunization of the larvae produced from immunized broodstock with a bivalent vaccine (Biv1 group and Pbs (Pbs1 group was performed by immersion at 20 days after hatch. Larvae produced from the Pbs group were unvaccinated as the control (Pbs2 group. Changes in the specific antibody and relative percent survival were measured. The Sa and Ah groups that could increase specific antibodies and protection against pathogenic bacteria were challenged with the homologous bacteria. The Biv group stimulated and protected against both S. agalactiae and A. hydrophila. The specific antibody of the Biv1 group was higher than the Pbs1 and Pbs2 groups. The last observation in this study showed that the relative percent survival of the Biv group after challenged S. agalactiae, A. hydrophila, and coinfection were 74.74 ± 3.18%, 73.81 ± 8.58%, and 71.48 ± 5.70%, respectively. The use of bivalent vaccines on the broodstock and larvae may be a strategy to reduce mortality in Nile tilapia larvae caused by single pathogen infection of S. agalactiae and A. hydrophila, or coinfection with both S. agalactiae and A. hydrophila.