Livestock Fish Egypt Aquaculture

Permanent URI for this collectionhttps://hdl.handle.net/10568/16619

Browse

Now showing 1 - 20 of 30

Detection of Tilapia Lake Virus in Egyptian fish farms experiencing high mortalities in 2015
(Journal Article, 2017-12) Nicholson, P.; Fathi, M.A.; Fischer, A.; Mohan, C.; Schieck, Elise G.; Mishra, N.; Heinimann, A.; Frey, J.; Wieland, Barbara; Jores, Joerg
Currently, tilapia are the second most important group of farmed fish worldwide, wherein Nile tilapia (Oreochromis niloticus) is the foremost cultured species (FAO 2005). In 2014, the global tilapia production was valued at 4.5 million tons and is expected to surge to 7.3 million tons by 2030 (FAO 2014). Specifically, Egypt represents over 90% of the commercial Arab aquaculture production and currently ranks second to China with regard to global tilapia output (FAO 2005). Since 2013, an increasing number of tilapia farms in Egypt have been experiencing high summer morbidity and mortality rates (WorldFish 2015). Such disease outbreaks are a major constraint to the aquaculture trade and have devastating economic and social consequences (Aly, 2013). Tilapia have become such an important global food source, not only because they are an inexpensive source of protein but also due to their favourable culturing characteristics such as, their mode of reproduction, omnivorous diet, fast growth, tolerance for high-density aquaculture and because they are relatively resistant to poor water quality and disease (FAO 2005). Despite this, various bacteria, fungi, protozoa and viruses have been associated with disease in tilapia aquaculture (FAO 2005). There have been many reports implicating bacteria in tilapia diseases and in particular, bacterial infections caused by Aeromonas or Streptococcus species. For example, A. hydrophila and A. veronii are the causative agents of Motile Aeromonas Septicaemia (Aly, 2013; FAO 2005). Far less has been reported regarding viruses causing diseases in tilapia (Bigarre et al., 2009; Mcgrogan, Ostland, Byrne, & Ferguson, 1998; Shlapobersky et al., 2010), especially in Egyptian farms (Aly, 2013). However, a new virus called Tilapia Lake Virus (TiLV) has been implicated in recent mass tilapia losses in Israel and Ecuador (Bacharach et al., 2016; Del-Pozo et al., 2016; Eyngor et al., 2014; Ferguson et al., 2014). Oddly, the virus seems to manifests itself as a problem of the brain in Israel (Bacharach et al., 2016; Eyngor et al., 2014), while it targets the liver of fish in Ecuador (Del-Pozo et al., 2016; Ferguson et al., 2014) and Colombia (Kembou Tsofack et al., 2017). Our aim was to detect potential pathogens in diseased tilapia that might account for the high summer mortalities observed in Egyptian fish farms. To this end, diseased fish were examined from eight farms in different areas of the Nile delta. Here, we report the detection of Aeromonas species and, for the first time, the presence of TiLV in Egyptian tilapia aquaculture. In September 2015, we visited eight commercial farms experiencing the so-called summer mortality spanning a large area of the Nile Delta (Figure 1). We randomly sampled 13–40 fish per farm and examined them macroscopically to determine disease prevalence (Table 1 and Table S1). External clinical examinations considered haemorrhagic patches, detached scales, open wounds, dark discoloration and fin rot as signs of disease. Two diseased fish per farm were dissected, and tissues from the head kidney were collected in Universal Transport Medium tubes (UTM™, Copan, Italy) and kept at 4°C during transportation before being stored at −80°C. Additionally, the head kidney, spleen and liver tissues were swabbed using Amies Agar Gel (with charcoal) swabs (Copan, Italy). As controls, 20 healthy tilapia were examined from WorldFish in Abbassa and two were dissected and processed as outlined above. A. veronii A. hydrophilia A. veronii A. ichthiosmia A. enteropelogenes A. veronii A. enteropelogenes A. jandaei A. veronii A. ichthiosmia A. enteropelogenes A. hydrophilia The presence of TiLV was tested using a PCR protocol published elsewhere (Eyngor et al., 2014). Briefly, 20–60 mg of head kidney tissue was homogenized in 1 ml TRIzol reagent (Thermo Fisher Scientific, USA) using Lysing Matrix B and D (MP Biomedicals, USA,) in a MP FastPrep-24 sample preparation system (MP Biomedicals) for 2 × 40 s, with cooling in between, at a speed of 6.5 m/s. Thereafter, the TRIzol reagent protocol was followed, with the exception that 1-Bromo-3-chloropropane (Sigma Life Sciences, USA) was used instead of chloroform. About 10 ng of purified RNA was used in a one-step RT-PCR reaction using the Thermo Scientific Verso 1-Step RT-PCR ReddyMix Kit (Thermo Fisher Scientific). The virus was detected in four farms (Figure 1, Table 1 and Figure S1) using a diagnostic RT-PCR amplifying a 250-bp fragment of segment 3 (Eyngor et al., 2014). Additionally, primers in coding regions from segments 4 (S4_F-AGCAGCAGCAGGAGAAAGAG and S4_R-ACCGTCCTGTTTCTGAATGG) and 9 (S9_F-TTGGTGATGTCACGATGGATA and S9_R-AGTTCTATCGCCAGCCATGT) were designed using the available genome sequence of TiLV isolate Til-4-2011 (GenBank accessions numbers KU751817 and KU751822). We were able to amplify a 358-bp and a 351-bp fragment from segment 4 and segment 9, respectively, from three of the five virus isolates. All amplicons, including the 250-bp amplicons derived from segment 3, were Sanger sequenced (microsynth.ch) and assembled. The trimmed sequences (segment 3 = 249 bp, segment 4 = 263 bp, segment 9 = 252 bp) were used for a comparative analysis against the sequences of the Israeli and Ecuadorian TiLV. Egyptian TiLV sequences were deposited in GenBank under accession numbers KY817381–KY817390. Nucleotide sequences were aligned using muscle (Edgar, RC. 2004 NAR). When comparing all sequences, segments 3, 4 and 9 had 18, 16 and 2 SNPs, respectively. This led to two non-synonymous substitutions for sequences derived from segments 3 and 4. The amino acid changes in segment 3 distinguished the Egyptian isolates from the Israeli and Ecuadorian isolates, while the ones in segment 4 were unique to either the Ecuadorian isolate or to the Egyptian isolate from farm 5. Segment 9 sequences were identical for all viruses investigated at protein level (Table 2). The TiLV from Ecuador showed 98% nucleotide identity to the Israeli strain (Bacharach et al., 2016; Del-Pozo et al., 2016; Eyngor et al., 2014), while the Egyptian TiLV isolates showed only 93% identity to the Israeli strain when comparing sequences from segments 3, 4 and 9. We built phylogenetic trees for each segment using phyML (Guindon et al., 2010). All trees were congruent pointing towards the absence of reassortment (Figure 2). The Egyptian isolates cluster together with high bootstrap support. Surprisingly, the Israeli isolate is closer to the Ecuadorian isolate than to the Egyptian isolates. Additionally, we investigated the presence of bacterial fish pathogens using swabs which were stored at 4°C until they were spread onto tryptic soy agar containing 5% sheep blood (BD, USA) and incubated aerobically at 30°C for 48 h. Single colonies were subcultured and used to identify the bacteria present in our fish samples by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF) using a Microflex LT instrument (Bruker Daltonics GmbH, Germany) with FlexControl (version 3.0) software (Bruker Daltonics) for the automatic acquisition of mass spectra in the linear positive mode within a range of 2–29 kDa (Bizzini, Durussel, Bille, Greub, & Prod'hom, 2010). We did not detect any Streptococcus species, but we found Aeromonas species in every farm (Table 1). Our aim was to identify candidate pathogens potentially responsible for the recent summer mortalities reported from Egyptian tilapia aquaculture (Worldfish, 2015). We visited eight commercial farms, covering different regions of the Nile delta and observed morbidities ranging from 43% to 100%. In every farm, we identified Aeromonas species which have been detected in Egyptian tilapia farming for many decades and have been linked to previous severe disease outbreaks (Aly, 2013). The new finding in trying to account for the recent Egyptian tilapia mortalities is the discovery of TiLV in 50% of the farms investigated. Notably, the application of a recently published Nested Reverse Transcription-PCR (Kembou Tsofack et al., 2017) probably would have resulted in a higher detection rate of TiLV. So far, TiLV has been implicated in mass tilapia deaths occurring also during the hot seasons in Israel and Ecuador. It is a segmented negative sense RNA virus that appears to be a real threat to global tilapia aquaculture. The absence of re-assortment and the closer similarity of Israeli to Ecuadorian isolates than to geographically closer Egyptian isolates could be due to anthropogenic influence via movement of feeds, live fish or water. Given our data, we cannot conclusively state that the emergence of this virus in Egyptian tilapia aquaculture is solely responsible for their summer mortalities, but it is a significant finding. Therefore, a prompt investigation into the prevalence of this virus in further regions of the Nile delta and how the Egyptian TiLV, which is divergent from the Ecuadorian and Israeli strain, manifests itself in Nile tilapia is required. Additional Future studies should investigate the effect of co-infections of pathogenic Aeromonas species with TiLV. Moreover, abiotic factors, such as water quality and temperature, should be investigated with respect to their effect on tilapia susceptibility to TiLV. Crucially, future work must focus on implementing existing diagnostic methods (Kembou Tsofack et al., 2017) into disease control policies. The development and application of an efficient vaccine would be the most effective disease control measure, but this endeavour requires more time. We are grateful to everybody involved in the sampling of tilapia in Egypt for this study. This work was supported by the CGIAR research programme Livestock and Fish, the University of Bern, and the Egyptian General Authority for Fish Resources Development. We thank Felix Drexler for his comments on the manuscript. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Benchmarking the environmental performance of best management practice and genetic improvements in Egyptian aquaculture using life cycle assessment
(Journal Article, 2017-02) Henriksson, Patrik J.G.; Dickson, Malcolm; Nasr-Allah, A.M.; Al-Kenawy, D.A.R.; Phillips, Mike
Egyptian aquaculture is gaining importance as an affordable and nutritious source of animal protein among Egyptians. Nile tilapia dominates production (77% of total production), followed by carps (17%) and mullets (11%). Egyptian tilapia farmers are, however, facing challenges with regards to financial viability and poor water quality. Fish farms are also contributing towards water pollution and other environmental impacts. In order to improve the situation, WorldFish launched the IEIDEAS project in 2011 with the ambition to train farmers in best management practices (BMP) and distribute the 9th generation of the Abbassa strain (G9). The present study aimed at evaluating any relative environmental gains that BMP and G9 offers compared to conventional farming using life cycle assessment (LCA). Inventory data representing 137 farmers and four groups (control, BMP, G9 and BMP + G9) were evaluated. Life cycle impact assessment results including quantitative uncertainties were then calculated and statistically tested, using Monte Carlo analysis and Wilcoxon paired significance test. Five impact categories were explored: global warming, eutrophication, acidification, freshwater consumption and land use. The G9 stain offered the greatest improvements across the evaluated impact categories, significantly reducing environmental impacts with between 12% and 36%. BMP, in the meantime, only offered significant improvements compared to the control with regards to eutrophication, acidification, freshwater consumption and land use. Meanwhile, BMP + G9 performed comparably to only G9 except for eutrophication where it had a significantly larger environmental footprint. More efficient feed utilization and higher productivity were the main reasons for the environmental improvements. Additional improvements that should be explored include improved feeds made of sustainably sourced raw materials, and better pond water management, including probiotics and paddle-wheels.
Increasing fish farm profitability through aquaculture best management practice training in Egypt
(Journal Article, 2016-12) Dickson, M.; Nasr-Allah, A.M.; Al-Kenawy, D.A.R.; Kruijssen, Froukje
Egyptian aquaculture production has grown rapidly to over one million tons per year so that it now provides most of the country's fish supply. However, Egyptian fish farmers have received little extension advice or training. An intervention starting in 2012 aimed to address this gap by providing best management practice (BMP) training for pond based tilapia monoculture and tilapia-mullet polyculture fish farmers. A series of field-based training modules were developed and designed with the participation of leading fish farmers and delivered through private sector farmer-trainers to over 2400 fish farm owners and managers. This paper reports on the results of an impact assessment survey carried out in 2015 comparing fish farm performance, production and profitability in randomly selected farms where the manager had received and was applying the principles of BMP training (BMP) and farms where the manager had not received IEIDEAS project training (control). The results show that although the two groups were very similar in terms of general farm characteristics, BMP farms were more likely to practice tilapia-mullet polyculture than monoculture of tilapia. The main BMP training messages apparent in the results were improved feed and fertilizer management. This resulted in more efficient food conversion ratios in BMP farms compared to control farms. Average fish yields and values were similar between the two groups, although BMP farms produced less small-sized tilapia and more mullet than the control farms. Lower feed costs resulted in significantly lower operating costs in BMP farms compared to control farms, whereas fixed costs were similar for the two groups. Average net profits were significantly higher in BMP farms compared to control farms equivalent to additional profits of over $15,000 for an average farm size of 7.5 hectares. Taking into account the number of farmers trained and BMP adoption rates suggests that $18.9 million additional profits were generated through the intervention in 2014. The results demonstrate that fish farms in mature aquaculture systems can benefit significantly from the adoption of improved farm management practices suggesting that similar approaches, including field-based BMP training and the use of private sector farmer-trainers should be used to accelerate the development of nascent aquaculture sectors in other parts of Africa.
Improving Employment and Income through Development of Egypt’s Aquaculture Sector (IEIDEAS) project
(Report, 2016-04-30) Dickson, M.; Nasr-Allah, A.M.; Kenawy, D.; Fathi, M.; El-Naggar, G.O.; Ibrahim, N.
The role of farmed fish in the diets of the resource-poor in Egypt
(Report, 2015-03-20) El Mahdi, A.; Krstic, J.; Abdallah, A.; Abdullah, H.; Kantor, Paula; Valpiani, N.
Theatre workshops help Egyptian women fish retailers lobby for their rights
(Video, 2014-09-30) WorldFish
Women fish retailers in Egypt are often forced to pay unofficial fees for their roadside market stalls. Exposure to the elements affects the women’s health and causes their produce to spoil, limiting their income. An interactive theatre project has helped boost the confidence and ability of these women to lobby their local government for retail licenses to protect their safety and rights as workers. The project is part of the Improving Employment and Income through Development of Egypt’s Aquaculture Sector project, funded by the Swiss Agency for Development and Cooperation.
Value chain analysis of the aquaculture feed sector in Egypt
(Journal Article, 2015-02) El-Sayed, A.F.M.; Dickson, M.W.; El-Naggar, G.O.
This study was carried out to evaluate the value chain performance of the aquaculture feed sector in Egypt, in terms of value addition, employment and profitability. The strengths and weaknesses of each link of the value chain were assessed and appropriate upgrading, management and development strategies were suggested. Quantitative data were collected for each link in the value-chain through structured questionnaires that were drafted and distributed to the key players in the sector; 25 fish feed mills and 34 fish farms covering different geographical and production regions. The results indicated that the Egyptian aquafeed value-chain is relatively simple; including only four main stakeholder groups. These are feed input suppliers, aquafeed producers, aquafeed marketers and traders and fish farmers. Between 50 and 99% of feed ingredients used in aquafeed production in Egypt are imported. About 90% of Egyptian aquafeeds are produced by the private sector in the form of conventionally pressed, pelleted feeds (80–85%) and extruded feeds (15–20%). About 85% of those producers sell their feeds directly to farmers with payment either in cash or on credit, while the remaining 15% sell through intermediaries such as traders. State-owned mills produced only 10% of total commercial fish feed production in 2012, exclusively in the form of pressed, pelleted feeds. Employment generation in private sector feed mills was 29.2 full-time equivalent (FTE) jobs per mill, with an average of 3.9 jobs per 1000 tonnes of feed produced. Employment generation in state-owned mills was much higher; with an average of 90.3 FTE per mill. Males represented 90% of the full-time employment in the state-owned mills and 96.6% in the private sector. Feed costs represent 75–90% of the total operating costs of the fish farms. The major factors impacting on the performance of the value-chain relate to inputs, to feed production, to fish farmers and to marketing and financial services. The study recommends actions to mitigate these issues including the local production of more feed raw materials, strengthening quality control and inspection, providing training for feed mills, better organization of fish farmers and improving the legal and policy environment.
Technical characteristics and economic performance of commercial tilapia hatcheries applying different management systems in Egypt
(Journal Article, 2014-04) Nasr-Allah, A.M.; Dickson, M.W.; Al-Kenawy, D.A.R.; Ahmed, M.F.M.; El-Naggar, G.O.
This study was carried out in order to understand the technical and economic characteristics of different Egyptian Nile tilapia (Oreochromis niloticus) hatchery systems. Hatchery operators at fifty tilapia hatcheries in four governorates were interviewed and four focus group discussions were held with 61 participants in March 2012. Technical characteristics and economic performance data were obtained for three tilapia hatchery systems: hapa-based in earthen ponds (hapa), hapa-based in greenhouse tunnels (greenhouse) and concrete tanks in greenhouse tunnels with water heating (heated greenhouse). The study showed that the average tilapia hatchery production was 9.92 million seed per year (5.82 million, 12.17 million and 12.25 million for hapa, greenhouse and heated greenhouse systems, respectively) while the average employment level was 4.5 full-time equivalents (FTE). On average 95.8% of hatchery production was sold as fry, while only 4.3% of seed production was sold as fingerlings. Both total costs and total revenues were highest in heated greenhouse hatcheries, followed by greenhouse-based and lowest in hapa-based systems. Net profits were highest in greenhouse-based systems (45.1% of sales), compared to both heated greenhouse (33.2% of sales) and hapa-based systems (37.6% of sales). Focus group discussions showed that hatchery operators currently face many critical factors: shortages of good quality brood fish; poor water quality and shortages of water; high fuel costs; lack of access to affordable finance; a ban on fry transport between governorates; and limited knowledge of best management practices. The study concluded that greenhouse-based hatcheries are more profitable than heated greenhouse systems which produce more but face additional costs and hapa-based hatcheries which are low-cost but have a shorter production period. Greenhouse-based hatcheries are also more likely to remain profitable when faced with financial shocks.
Egyptian fish farmers learn best aquaculture practices
(Video, 2014-02-05) WorldFish
Teaching Egyptian fish farmers the industry’s best aquaculture practices has helped increase their production and income. Strengthening the industry’s small and medium-scale farms will generate new employment opportunities and meet the country’s growing demand for fish. The training is part of the Improving Employment and Income through Development of Egypt’s Aquaculture Sector project, which is funded by the Swiss Agency for Development and Cooperation and aims to create 10,000 new industry jobs.
The Egyptian tilapia value chain experience
(Presentation, 2014-11-19) Kruijssen, Froukje
Rapid integrated assessment of nutrition and health risks associated with tilapia value chains in Egypt
(Report, 2014-02-15) Eltholth, Mahmoud; Fornace, K.; Häsler, Barbara; Rushton, Jonathan
Informal fish retailing in rural Egypt: Opportunities to enhance income and work conditions for women and men
(Report, 2014) Kantor, Paula; Kruijssen, Froukje
Aquaculture: Fish for a food secure and prosperous Egypt
(Poster, 2014-08-15) WorldFish
Small and medium scale aquaculture value chain development in Egypt: Situation analysis and trends
(Report, 2014-07-15) Hebisha, H.; Fathi, M.
Value chain analysis of the Egyptian aquaculture feed industry
(Report, 2014-04-01) El-Sayed, A.F.M.
Development of the aquaculture value chain in Egypt: Report of the National Innovation Platform Workshop, Cairo, 19-20 February 2014
(Report, 2014-04-01) Mur, Remco
A review of fish diseases in the Egyptian aquaculture sector: Working report
(Report, 2013-07-15) Aly, S.M.
Enhancing the employment of women fish retailers in Egypt
(Presentation, 2013-10-14) Kantor, Paula
Improving the working conditions of women fish retailers in Egypt
(Brief, 2013-12-31) Hussein, S.; Mounir, E.; Sedky, S.; Nour, S.A.; Kantor, Paula
Institutional, policy and regulatory framework for sustainable development of the Egyptian aquaculture sector
(Working Paper, 2013-11) Goulding, I.; Kamel, M.

Browse

Recent Submissions