ABSTRACT
This study was undertaken in the main Côte d’Ivoire fish farming production regions. Fish farming were surveyed on the basis of socio-economic characteristics of fish farmers, farming practices and production depending to the systems. Results show that majority of fish farmers used semi intensive (51.8%) and extensive (42.9%) systems. Intensive system represented only 1.3% and rice-fish system 4.0% of fish farms. Tilapia, Heterotis and Catfish were the most species reared with frequencies depending to the system. In intensive system, rearing structures were tanks and floating cages and farms owner were native (50%) economic operator (75%) or salaried (25%). In contrast, in semi intensive systems, the popular rearing structures were earthen ponds (68.6%), and farms belong to native (61.5%) farmers (46.3%). Extensive and rice fish farming used earthen ponds associated to dams (52.7-66.7%) and 45.7-50% of proprietary were allochthonous famers (77.5-91.7%). Imported (50%) and national commercial feeds (50%) were used in intensive system. In semi intensive system, national commercial feeds (55.13%), agro-industrial byproducts (46.79%) and feeds produced by fish farmers (33.97%) were largely used while agro-industrial byproducts and/or non-conventional feeds were used in extensive and rice-fish system to feed fish. The average farm production of semi intensive and extensive systems most practiced varied between 395.25 and 2937.12 kg/year. The results suggest that optimization of the Ivorian fish farming production need the adoption of appropriate production practices. They also emphasize the need to promote the intensive and semi intensive systems to increasing marketable fish production.
Key words: Fish farming, System, socio-economic, farming practices, production.
Fish provides animal protein, essential fatty acids and micronutrients (Wang et al., 2006) and consumption improves the quality of the diet which leads to an improved nutritional status in developing countries found in Africa, Asia and Oceania (Kawarazuka, 2010). Calculated from the FAO food balance, fish contributes more than 1/3 of the total animal protein supply in most of African countries (FAO, 2009). For these peoples, aquaculture and small-scale fisheries contribute to improving fish availability and nutrition security. However, expanding aquaculture is more perceptible by interventions in the amount of production, species variety, fish feeds used and the improvement of practices and technologies (Kawarazuka, 2010). In fact, during the recent years, world aquaculture fish productions have been substantial increased and accounted for 44.1 percent of total production from capture fisheries and aquaculture.
It is the same in many African countries where aquaculture fish productions have considerably increased. During the year 2000 to 2014 the production in Africa has increased by a rate of 3.28 from 399 688 to 1 710 900 t while Sub-Saharan Africa aquaculture production has increased by a rate of 9.18 from 55 702 to 556 900 t (FAO, 2014, 2016). The expansion and production of aquaculture in northern part of Africa especially in Egypt with 1 137 100 tonnes in 2014 influence mostly African aquaculture production (FAO, 2016). Some Sub-Saharan Africa aquaculture production remains low despite many years of practice. However, Nigeria (313 231 t), Ouganda (111 023 t), Ghana (38 545 t), Kenya (24 098 t) and Zambie (19 281 t) are by far the five largest producers while Côte d’Ivoire production accounts only 3750 t in 2014 (Satia, 2017; FAO, 2015).
This production contributes to 4.12 percent of inland production (sum of capture fisheries and aquaculture) and remains insignificant to meet the national annual fish consumption estimated between 250 000 and 300 000 tonnes despite his richness on the human and natural resources and his potentials to compete with the Africa leading aquaculture countries (FAO, 2008, 2015). Otherwise, Africa aquaculture sector is characterized by extensive, semi-intensive, intensive and integrated rice-fish systems culture. Polyculture or monoculture of tilapia Oreochromis niloticus, carps and catfish are practiced in earthen ponds, cages, racesways, tanks and recirculating aquaculture systems (Hecth, 2007, Ozigo et al., 2014). Natural and/or supplementary feeds are used to feed fish. As supplementary feeds, non-conventional feeds, agro-industrial byproduct, farm-made feeds, complete pelleted floating, slow-sinking and sinking aqua-feeds are used (Gabriel et al., 2007; Hecth, 2007; Ozigo et al., 2014).
Consequently, aquaculture practices and production highly varying by region, countries, peoples and the level of financial resources which influence productions systems, fish species, practices, and feeds used (FAO, 2016). Also, commercial fish farm production is variable depending on the production systems employed and the level of his intensification (Hecht, 2007). In addition, the choice of farming system varies according to the motivation and circumstances of the farmers. Therefore, size of fish farms, species of fish bred, management practices, feeding, stocking and water quality management are essential to increase production, fish quality and marketability (Rana and Hasan, 2013; Ozigbo et al., 2014; Abboud et al., 2015). This study was carried out to compare fish farms, socio-economic characteristics of fish farm owners, farming practices and production in different farming system in Côte d’Ivoire regions well-known for fish farming in order to analyze the production system performances and explain the Ivorian aquaculture poor production.
Fish farms survey
The study was conducted in fifteen (15) main regions of fish production in Côte d’Ivoire, West Africa in collaboration with Kimou et al. (2016) from May to November 2013. Fish farmers were identified in each region with data and guidance given by local fish farmer’s organizations and the regional technical assistances of Ivorian state agriculture and fisheries ministry. All fish farmers having accomplished at least one harvest in the past year were surveyed. Each of the respondent via a personal structured interview, questioned about fish farming management and practices, socio-economic characteristics of fish farms owners, data of fish growth and production of farms. A total of 301 fish farmers were surveyed in regions visited. The frequencies of fish farmers visited by region and city and their localization were presented in (Table 1) and Figure 1. All the data recorded were grouped based on the type of farming system defined by New (1987) to Lazard (2009) and Avit et al. (2012).
The intensive system is characterized by fish monoculture in ponds, concrete or aluminum tanks and floating cages. In this system, fish are intensively fed with industrial imported or national high quality fish feeds. The semi-intensive system is characterized by the mono or polyculture of fish cultured. Fish were grown in earthen ponds, enclosed cages, happas, cement ponds and/or ponds dams. They were fed with agricultural or agro-industrial byproducts, farm-made feeds and/or national industrial feeds. Also natural food organisms contribute significant amount of nutrient necessary for fish growth. In this system, compounded feeds are regularly used to supplement natural food to maximize yield. Concerning extensive system, fish were grown in monoculture or polyculture in ponds, ponds dams, and/or dams and were occasionally fed with agro-industrial byproducts and non-conventional feeds. Integrated rice-fish system is characterized by associated culture of rice and fish in the same time in earthen ponds or ponds dams thus; Agro-industrial byproducts and non-conventional feeds are regularly or occasionally used to feed fish.
Data analysis
Survey data were analyzed using Sphinx version 4.5 software packages. Growth and farm production data were analyzed using descriptive statistics and tests of differences between means were done using one way analysis of variance (ANOVA) with Statistica version 7.1. The effects of treatment were considered to be significant at p < 0.05.
Production systems, characteristics of fish farms and farming practices
The survey revealed that basically four different types of fish production are present on farms visited in the main areas of fish production in Côte d’Ivoire which were intensive, semi-intensive, extensive and integrated rice-fish system. Majority of fish farmers used semi-intensive (51.8%) and extensive (42.9%) production systems. Only 4.0% and 1.3% of fish farmers carried out rice-fish and intensive systems, respectively. Fish farms are localized mostly in the rural areas in intensive (75.0%), semi-intensive (57.1%) and extensive (69.0%) production systems contrary to rice-fish system (41.7%). The number of farm years’ experience ranged from 5 to 10 years for 50% of fish farms in intensive system. The majority of semi-intensive (57.7%) and extensive (51.2%) farms had less than 10 years of fish production practice when 75.0% of rice-fish system farms had more than 10 years of fish production.
The size of the water used was less than 1 ha in most semi-intensive (75.6%), extensive (56.5) and rice-fish system in contrast to intensive system (25.0%). Farms rearing structures were generally earthen ponds associated or not to pond-dams in semi intensive, extensive and rice-fish system. Intensive system used basins and raceways in recirculating aquaculture system (25.0%) or floating cages associated or not to earthen ponds and tanks. In intensive system, all farms were managed by professional while in the others three systems 60.3 to 83.3% of farms were managed by the farms owners themselves (Table 2). Farming practices under different production systems are presented in Table 3. In the intensive and semi-intensive systems most of the farmers did make control harvesting (100 to 76.9%) and all farmers fed regularly fish contrary to extensive and rice-fish systems.
Nearly 35.7 and 41.7% of farmers in extensive and rice-fish systems, respectively practiced control harvesting and the total of 98.4% (extensive) and 33.3% (rice-fish system) fed occasionally fish. All of the farmers in intensive and semi-intensive system sexing tilapia were compared to 66.7% of farmers in rice-fish system. The weight of tilapia sexing was less than 40g for 100% of farmers in intensive system and nearly 75% of farmers in the semi-intensive and rice fish farming system. Feeds were presented in majority on pellet form and quantified by rationing table in intensive system. Almost 61.5% of feeds used in semi-intensive systems were presented on flour form and 62.5% of farmers have measuring tool to quantify the feeds to feed fish. In extensive and rice fish farming system, all the feeds are presented on flour from and nearly 83% of farmers used measuring tool also.
Socio-economic characteristics of fish farms owners
Table 4 describes the socio-economic characteristics of the study respondents. A total of 50% of fish farm owners in intensive and 61.5% in semi-intensive systems had their farm in their native region. In contrast, farm owners in extensive (45.7%) and rice-fish system (50%) were native from other regions of Côte d’Ivoire. Regardless of the production system, non-Ivorian native fish farm owners represented only 10.3-25.0%. Women in fish production represented 2.3 and 9.6% in the extensive and semi-intensive respondents, respectively. Fish farm owners were primarily to be the men (90.4 to 100.0%) in all production systems. Majority of farm owners in intensive, semi-intensive and extensive systems were still within age bracket 40 to 60 years. The highest percent (50.0%) of farm owners aged more than 60 years old was recorded in rice-fish system. Main professional activity of farm owners was economic operator for 75.0% in intensive system, and farmers for majority of owners in semi-intensive (46.2%), extensive (77.5%) and rice-fish system (95.5%).
Fish species bred
Fish species bred on farms are presented in Table 5 under different production systems. Results showed that Tilapia O. niloticus is the main species breed (92.3 to 100%) on the farms followed by African bonytongue Heterotis niloticus found in 72.1 and 41.7 % of semi-intensive and rice-fish system, respectively. Nearly 16.6 to 37.82% of catfish were bred on fish farms surveyed. However, tilapia and catfish were met in all farms, H. niloticus was met on semi-intensive, extensive and rice-fish system and Chrysichthys nigrodigitatus, Parachana Africana and Labeo coubie were few regained (0.64 to 9.6%) in semi-intensive and extensive systems.
Fish feed used
Different feeds were used in farms to fed fish depending on farm production systems (Table 6). Only imported (50%) and national (50%) industrial commercial feeds were used in intensive system. Commercial feeds (50.6%), feeds produced by fish farmers (33.9%) and agro-industrial byproducts (46.8%) were used in semi-intensive system. However, agro-industrial byproducts were most used followed by national industrial commercial feeds (39.7%), and feeds produced by farmers. Agro-industrial byproducts accounted for 100% while non-conventional feeds were for 33.3 to 48.8% in extensive and rice-fish systems. Among the Agro-industrial byproducts, rice bran and maize bran were most used in semi-intensive (2.1-26.9), extensive (83.7-100%) and rice-fish systems (100%).
Growth and production data
Length of production, tilapia, heterotis and catfish average commercial weight, farms production, total production and contribution to the total production during the final harvest for all the four systems are summarized in Table 7. Results showed that the lowest (p<0.05) length of production was obtained in intensive system followed by semi-intensive and rice-fish systems. Extensive system reported the highest (p<0.05) length of production. Tilapia commercial weight was significantly (p<0.05) higher in intensive system than in semi-intensive and rice-fish systems while the lowest average tilapia commercial weight was observed in extensive system. In contrast, the highest average catfish commercial weight was recorded in semi-intensive, following by extensive when hyper intensive and rice-fish systems recorded the lowest weight. Average commercial weight of Heterotis was insignificant between semi-intensive, extensive and rice-fish systems. Average farms production values was higher in hyper intensive system followed by intensive, semi-intensive, extensive and rice-fish farming. Hyper intensive showed the highest total production data followed by intensive, semi-intensive extensive and rice-fish systems. The percentage contribution on harvested population reported was 51.18% in hyper intensive and 34.48% in semi-intensive systems. Intensive, extensive and rice-fish system contributed very weakly (0.35 to 5.94%) to the total production.
Results show that in Côte d’Ivoire the aquaculture production is dominated by low size semi intensive and extensive systems using earthen pond associated or not to pond-dam manage in majority by the farm owners. This is due to the fact that intensive system practice remains more expensive and need a lot of financial and technical assistances (Ozigbo et al., 2014). Therefore, the low presence of integrated rice-fish system despite the longtime of practiced (10 years and above for 75%) in the fish farms could express the few number of fish farmers among the rice farmers. The high number of farmers in fish farming was already reported by Brechbühl (2009) and El-Sayed (2013a). These farmers are cocoa, coffee, palm oil, rubber and over agricultural culture farmers at the time, so fish culture is a secondary activity for them. Owing to this, they did not spend much time and money to fed and culture fish. According to Gabriel et al. (2007) a lot of proportions of farmers and rural small scale operators in semi-intensive and extensive fish farming systems as secondary activity to agriculture are the major reasons of low aquaculture production in the most sub-Saharan Africa countries. The same trend was observed in Côte d’Ivoire.
Independently to the system, fish farmers seem to be practiced by Ivorian men generally farmers with an age ranged between 40 and 60 years. Traditionally, men are deemed to be the head of household unit and women are fish sellers (Nunoo et al., 2012). Also the low presence of women in fish farming would be due to women's common societal constraints such as access to land, water, management, capital (credit), the freedom to undertake, use of their incomes and to invest (FAO, 2011a, b; Karacayir and Sacik, 2016). However, women represent a real potential to the agriculture development in general (Odongo and Muhua, 2015). For this reason, fish farming must be promoted and facilitated to the Côte d'Ivoire women. Otherwise, the high frequency of farmers in extensive system affected negatively a lot of fish feed choice. In fact, proximate and mineral compositions of most feeds used (non-conventional feeds, agro-industrial byproducts, feeds formulated by fish farmers and feed sellers) have low nutritional quality due to their low protein content, low protein/energy ratio with high fibre and variety of anti-nutritional substances content (Tacon and Jackson, 1985; Guillaume et al., 1999; Francis et al., 2001). These feeds not always meet requirement of fish cultured.
However, in extensive and semi-intensive systems they can support the organic fertilization in the ponds to improve availability of natural foods very good consumed by some cultured fish such as tilapia, H. niloticus, African carp, Labeo coubie and parachanas to support their growth (Oswald et al., 2003; Adande and Fiobe, 2015). These low input practices could be explained by the high frequency of H. niloticus in polyculture. In fact, growth of this fish was largely supported by the natural foods supply in polyculture with tilapia in earthen pond (Monentcham, 2009). In addition, the disrespect of good farm management and practices like sexage, stocking density and feeding practices by some fish farmers consequently resulted in semi intensive and extensive system, long length of commercial fish production, low weight of commercial tilapia and low production capacities of farms. In these circumstances, harvested population report was more influenced by only the one fish farmer in hyper-intensive system and a total of 156 fish farmers in semi-intensive system contribute only to 34.18%.
The low frequency of fish farmers in intensive system and the low production potential of farmers in semi-intensive and extensive system could explain the poor production of aquaculture in Côte d’Ivoire. According Adeoti (2002) and Idumah (2006) education, social capital, and large farm size enhances productivity in agriculture. In the same trend, El-Sayed (2013b) reported that adoption mono-sex tilapia intensive culture in earthen ponds, tanks and cages and expansion of local commercial aquafeed manufacturing industry in Egypt were consequently improved Egyptian aquaculture production. Compared to Nigeria, Uganda, Ghana, Kenya and Zambia, the top five African countries fish producers, the same fish production structures (earthen ponds, cages, concrete tanks and recycling pump) were used in semi-intensive and intensive fish culture in Côte d’Ivoire fish farms (Ozigo et al., 2014; Munguti et al., 2014; Satia, 2017). Also tilapia, catfish and cyprinids are the main inland species groups cultured. However, high levels of fish production in related countries are due to the advanced in techniques and technicalities from the last 15 years in comparison to the Côte d’Ivoire were revolutions were not yet noticed in politic, investments and strategies of the aquaculture.
According to Satia (2017), the growth of aquaculture in some African countries is due to the emergence and intensification of private sector, expansion to large commercial cage culture aqua-farms, development of appropriate technology for producing all-male tilapia fingerlings, seed production, establishment of efficient commercial hatcheries, investments in development, significant private and public investments in feed mills, processing and marketing and use of new production system and of locally quality fish feeds. Therefore, improve Côte d’Ivoire aquaculture production shall be past necessarily by private and national investments in local high quality cost-effective fish feeds designed for species and life stages, in hatcheries for production of all-male tilapia fingerlings, in intensification and massive use of new production systems.
Ivorian aquaculture is characterized by low frequency of intensive system and low production levels of semi-intensive and extensive system due to financial limits, high presence of farmers among the owners, the use of low cost non quality feeds and disrespect of good farm management and practices in most of the farms. These problems result to the long length of production with low tilapia commercial weight, increasing tilapia polyculture with H. niloticus and fish farms production remains low. These results express the need to promoting investments in intensive fish farming system in Côte d’Ivoire by national and international economics operators. There are also express the need to train fish farmers on management, feeding, and production practices. However, it is essential to put at the disposal of fish farmers locally produced quality fish feeds at the least possible cost manufactured with the good processing methods which take cognizance of the requirements of the various species and stages of fish cultured.
The authors have not declared any conflict of interests.
The authors are grateful to Ivorian strategic program to support scientific research for the financing of this project, Project number 97, 2012. In addition, authors would like to thank the national association of fish farmers (ANAQUACI), regional fish farmer organizations and the regional extension officers of Côte d'Ivoire agriculture and fishery’s Ministry for their assistance during the survey.
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