An Evaluation of Seed Nursing and Seed Distribution in Kandal, Prey Veng and Takeo Provinces, Cambodia

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1 An Evaluation of Seed Nursing and Seed Distribution in Kandal, Prey Veng and Takeo Provinces, Cambodia by Sin Sovanara 1, Ouk Vibol 2, Chheng Touch 2 and Don Griffiths 3 1. Final year student of the Royal University of Agriculture, Phnom Penh 2. Fishery Officer, Department of Fisheries and Counterpart of the MRC/DoF/Danida Fisheries Project in Cambodia 3. Chief Technical Advisor, MRC - Rural Extension for Aquaculture Development Project ABSTRACT To stimulate aquaculture development, READ supported the establishment of three on-farm trial nurseries in Kandal, Prey Veng and Takeo provinces, where there was high potential for fish culture but a shortage of locally available, high quality fish seed. The aim of this paper is to evaluate fish seed nursing and seed distribution in the above provinces, where the READ project operates cm Silver Barb (Barbodes gonionotus), Tilapia (Oreochromis niloticus), Common Carp (Cyprinus carpio) and Silver Carp (Hypophthalmichthys molitrix) fry, supplied by READ, were stocked in prepared nursery ponds at a rate of fry per m 2. The fry were fed a soya bean, rice bran and broken rice mixture at rates equivalent to kg for 10,000 fish seed daily. Thirty days nursing produced fingerlings ranging from cm (total length). The nursery at Kandal province gave the best results because of good pond preparation and thorough management. The survival rate of fry to fingerlings ranged from 46 78%, with the highest survival found in Takeo. The majority of seed produced was sold to READ on-farm trialists in the 1999 season. Net profit ranged from 21 55%, with Takeo showing the highest net profit. A comparison of different seed production and nursery packages under different projects within Kandal, Prey Veng and Takeo provinces found that survival and growth of fish at READ nurseries was comparable or better than at AIT Outreach, SAO Scale and PADEK hatcheries, and that READ s mean cost of production per unit area of pond was lowest at 112,530 Riel per 100 m 2. While both income and return against investment per unit area were significantly higher for AIT Outreach and PADEK nurseries than READ nurseries, the READ nursery package may still represent a viable low risk option for small-scale nursery farmers, who are generally unable to access formal credit. READ will consider recommending that nursery farmers increase their stocking densities and the sale price of their fingerlings. 1. INTRODUCTION While wild fish have long been a traditional source of animal protein in the diet of Cambodian people, culturing fish is a relatively recent activity. Pond culture contributes only 10% of total cultured fish production, with the remainder coming from cage (72%) and pen (18%) culture (DOF, 2000). In the last decade considerable government, donor agency and NGO effort has been made to promote the development of small-scale aquaculture and primarily pond culture of fish, especially in Takeo, Prey Veng, Kandal, and Svay Rieng provinces, where wild fish are in short supply. The Family Food Production Program (FFP), a joint activity between the Royal Government of Cambodia and UNICEF, undertook the first activities. By 1992, 10,000 households were receiving assistance and 8,000 family ponds had been constructed by FFP in Takeo, Kandal and Prey Veng provinces. The Rural Extension for Aquaculture Development (READ) Sub-Component in Cambodia in collaboration with the Department of Fisheries is working in Takeo, Prey Veng and Kandal provinces to increase the income of small-scale farmers through fish culture. In 1999 READ worked with 45 onfarm-trial farmers (15 per province) to test the technical and economic feasibility of READ recommendations for pond fish culture

2 Since fish seed supply was identified as a constraint to aquaculture development, in the 2000 season READ provided training, technical and financial inputs to the best 1999 OFT farmers in each province to develop them as fish nursery farmers. Support included training, provision of fish seed, and assistance with pond preparation and transportation of seed from hatcheries to each nursery. In addition, READ funded the sinking of a tube-well at the nursery in Takeo province. Efforts were concentrated on fingerlings of four fish species, namely Silver Barb (Barbodes gonionotus), Tilapia (Oreochromis niloticus), Common Carp (Cyprinus carpio), and Silver Carp (Hypophthalmichthys molitrix), because they were easy to spawn and were popular with small-scale grow-out farmers. READ sponsored a B.Sc. student from the Royal University of Agriculture, Chamkar Dong, to conducted a two-part study entitled An evaluation of seed nursing and seed distribution in Kandal, Prey Veng and Takeo provinces of Cambodia. The first part of the study assessed the production and economics of each READ nursery and identified where the fish seed was distributed. A secondary study was also undertaken to compare and contrast the technical and operational economics of seed production and nursery packages of READ Project, SAO, PADEK and AIT Outreach programs. 2. METHOD The fieldwork for this study was conducted over three months from June 17th and September 17th, All three READ nursery farmers, Mr. Ork Son, Mr. Sot Sen and Mr. Chhum Try, from Prey Veng, Takeo and Kandal provinces respectively, were interviewed in Khmer, using a structured questionnaire containing mainly closed questions. Similarly, a questionnaire interview was also conducted with three PADEK, seven AIT Outreach and nine SAO (Scale) nursery farmers in the READ project area. The questions focused on pond size, pond preparation methodology, seed size at stocking, stocking density, feed types and quantities, monitoring, harvesting, production costs and income. All collected data were entered onto a computer and analyzed using Microsoft Excel software. 2.1 READ nurseries Mr. Ork Son s nursery farm in Cheur Katch commune, Barphnum district, Prey Veng province, has three ponds with a total area of 428 m 2. The 300-m 2 nursery pond is split into two equal portions by nylon-mesh netting. The ponds are m deep. Mr. Sot Sen s nursery farm, located in Trapeang Krasang commune, Bati district, Takeo province, has four square ponds with a total area of 415 m 2, which the family dug by hand themselves. The nursery ponds range in size from m 2 and are m deep. A 1.0-m high external dike prevents flood and the entry of fish predators. Mr. Chhum Try s nursery farm is located in Shnor commune, Angk Snoul district, Kandal province. Mr. Try dug his two large ponds himself; they have a total area of 616 m 2. Both ponds are divided equally into two by nylon mesh netting supported on bamboo posts. See Table 11.1 for characteristics of the three ponds. Nursery pond preparation follows the same pattern in all three provinces. Ponds are first drained and dried for one day before lime is applied at a rate of kg ha -1 to kill predators, disease vectors and to buffer water ph. Ponds were refilled, with water passed through a fine meshed cloth, to exclude predatory fish and three days later were fertilized with cow manure, green manure, urea and DAP at rates of 4,000 5,000, 3,000 4,000, 200 and 100 kg ha -1 respectively. Table 11.2 shows the quantities of fertilizers and lime used by the READ nursery farmers. Table 11.1: Nursery pond characteristics Province Farmer Total pond area (m 2 ) Pond number Pond size (m 2 ) Pond depth (m)

3 Prey Veng Mr. Ork Son 428 Takeo Mr. Sot Sen 415 Kandal Mr. Chhum Try 616 P P2 150 P3 128 P P2 100 P3 100 P4 100 P P2 154 P3 154 P4 100 Table 11.2: Fertilizers used for pond preparation in each province Total Lime (kg) Urea (kg) DAP (kg) Cow manure (kg) Green manure (kg) Farmer pond size (m 2 Tot. 100m 2 Tot. 100m 2 Total 100m 2 Total 100m 2 Total 100m 2 ) Ork Son Sot Sen Chhum Try Once the nursery ponds were green with natural feed, normally 7 15 days after fertilization, fry of one of the following fish species, Silver Barb, Tilapia, Common Carp, or Silver Carp, were stocked at fry per m 2. Table 11.3 shows the size and quantities of fry nursed, by species, by the READ nursery farmers in each province. Table 11.3: Fish seed species, fish size and numbers of fish stocked in each province Province Farmer Pond size Species Fish seed size Stocking density Quantity (m 2 ) (cm) (fry per m 2 ) Kandal Chhum Try 208 Tilapia , C. Carp , Silver Carp , Silver Carp ,750 Total 616 Total 27,000 Prey Veng Ork Son 150 Silver Barb , Silver Carp , Tilapia , C. Carp ,750 Total 428 Total Takeo Sot Sen 100 Tilapia , Silver Carp , Silver Barb , C. Carp ,000 Total 415 Total 12,500 In addition to natural feed induced by regular pond fertilization, nursery farmers began supplementary feeding 4 5 days after stocking the fish. The feeds were a combination of rice bran, broken rice and/or soya bean, with duckweed being fed when the fish were larger. Choice of fish feed depended primarily on price and what the nursery farmer could afford, rather than on feed quality or formulation. Table 11.4 shows that rice bran was the main feed ingredient fed by all farmers. Mr. Ork Son from Prey Veng province fed at the highest rate (equivalent to 1.37 kg day seed -1 ); this rate was twice that of Mr. Sot Sen from Takeo province. Dietary protein levels ranged from 12 20%, with the diet containing 25% soya bean being the highest. Table 11.4: Feed type and quantity used

4 Farmer Province Rice Broken rice Soya Protein diet Quantity of feed fed for bran bean 10,000 fry (kg.day -1 ) Ork Son Prey Veng 80% 8.5% 11.5% 16% 1.37 Sot Sen Takeo 75% 0% 25% 20% 0.64 Chhum Try Kandal 50% 50% 0% 12% 0.74 Mean 16% 0.92 Water quality was monitored daily by secchi disc and fertilizer was applied when water transparency increased. Mr. Sot Sen of Takeo applied bat manure to increase the natural productivity of his nursery ponds at a rate of 50 kg ha -1 every 15 days. Other routine daily management practices included checking pond embankments, maintaining pond water levels, scaring away predatory birds, and removing from the ponds any fish that appeared diseased. The seed were nursed for 30 days before being harvested daily until the pond was empty and sold to grow-out farmers. Word of mouth was sufficient for neighboring grow-out farmers to know when fingerlings would be available, since distances between the nursery and grow-out ponds was only short. Most fish were transported in buckets, plastic jars or plastic bags on foot or by bicycle, cart or motorbike. The majority of seed (74 95%) was sold within the province where it was produced, with only limited amounts being sold outside the READ work area. Distribution percentages are given in Table Table 11.5: Fingerling distribution (%) Farmer Province In project area (%) Outside project area (%) Ork Son Prey Veng 95 5 Sot Sen Takeo Chhum Try Kandal 95 5 Mean Other nurseries PADEK and AIT nursery farmers had a mean of three nursery ponds each, while most SAO nursery farmers possessed only a single pond. Table 11.6 shows that PADEK, AIT and SAO nursery farmers had a mean total area of ponds of 625, 492 and 150 m 2 respectively. The majority of SAO nursery farmers used nylon-mesh hapa nets (2 x 3 x 1 m) for nursing. Table 11.6: Numbers and size of nursing pond used by each farmer in the project Project Mean number of Mean of total pond area ponds (m 2 Mean pond size (m 2 ) ) PADEK AIT SAO Pond preparation method and rates of lime and fertilizer application by PADEK, AIT and SAO nursery farmers were similar to those used by READ (see Table 11.7). AIT farmers, however, applied very little organic fertilizer because they believed that it encouraged the growth of zooplankton, which would eat the small fry. All projects screened water inflows when filling nursery ponds. Table 11.8 shows that the different agencies nurse a total of five species: AIT nurses two species, READ and PADEK four and SAO five species. Only Silver Barb is indigenous to Cambodia. The stocking size and density vary considerably between the different agencies. READ stocks larger-sized seed at lower stocking densities than all the other agencies. PADEK and AIT stock Common Carp hatchlings directly for nursing and therefore stock at higher rates. Table 11.7: Rate of lime and fertilizer application (kg/100 m2) for pond preparation

5 Project Lime Urea DAP Cow manure Green manure PADEK AIT SAO READ Table 11.8: Fish size and stocking densities in PADEK, AIT, SAO and READ nurseries Project name Fish species Size (cm) Stocking density (fish per m 2 ) READ PADEK AIT SAO Tilapia Silver Carp 3.41 Common Carp 2.58 Silver Barb 2.41 Tilapia Common Carp 0.67 Silver Carp 0.67 Mrigal 0.90 Tilapia Common Carp 0.87 Tilapia per m 2 of hapa water Silver Carp 1.50 surface area Common Carp 1.33 Silver Barb 1.30 Mrigal 2.18 Rice bran was the major feed used by all farmers. Unlike READ farmers, who used basic feed mixes containing only rice bran, broken rice and soya bean, AIT and SAO nursery farmers also added other feed ingredients including Hygro and vitamin pre-mix. Nursery farmers from other agencies generally fed at lower rates that READ farmers (Table 11.9). Table 11.9: Feed mix and mean quantity fed for READ, PADEK, AIT and SAO seed nursing Project Rice bran Broken rice Soya bean Hygro Vitamin premix Quantity fed for10,000 fry (kg) READ 68% 20% 12% 0.92 PADEK 83% 4% 13% 0.40 AIT 70% 13% 5% 12% 0.12 SAO 84% 3% 13% 0.65 Farmers nursed for days before harvesting seed. Like READ, nursery farmers harvested fish seed daily early in the morning using a hapa net to catch and hold the fish for 3 5 hours until customers arrived to purchase and take them away. Most nursery farmers sold to bulk buyers who held the fish for 5 7 days before selling them on to grow-out farmers % of seed from PADEK and AIT nursery ponds was sold outside the province where it was produced. 3. RESULTS Survival from fry to fingerling ranged from 46 78%. Mr. Sot Sen s fish had the best survival rates, with over 72% for three of the four species nursed (Table 11.10). The low survival rate at Ork Son s nursery was caused by some fish (estimated to be 25%) escaping during flooding. The low survival of Chhum Try s Tilapia was due to large post-stocking mortality, because the fish were not properly conditioned prior to transportation. Good pond preparation and careful management resulted in acceptable growth of fish in READ nurseries, ranging from cm day -1 and with the fish reaching 5 7 cm total length after 30 days of nursing. Although he used feed mix with only 12% protein, the growth rate of fish was generally

6 best in Mr. Chhum Try s nursery (Table 11.10). Surprisingly, Tilapia increased in length faster than Silver Carp, which are the faster growing fish species under normal conditions (Table 11.11). Table 11.10: Specific daily growth and survival rates Farmer Specific growth in a day (cm.day -1 ) Survival rate (%) Tilapia S. Carp C. Carp S. Barb Tilapia S. Carp C. Carp S. Barb Ork Son Sot Sen Chhum Try Mean Table 11.11: Stocking and harvesting length by species in READ nursery ponds Farmer Tilapia (cm) Silver Carp (cm) Common Carp (cm) Silver Barb (cm) Stock Harvest Stock Harvest Stock Harvest Stock Harvest Ork Son Sot Sen Chhum Try Mean Table shows that the mean daily increase in fish length was greatest for Tilapia and Silver Carp in READ nurseries and similar for other species. This is probably because READ nursery ponds were well fertilized and both Tilapia and Silver Carp actively feed on phytoplankton. Table 11.12: Mean increase in length of fish seed in READ, PADEK, AIT and SAO nurseries Project Tilapia (cm) Silver Carp (cm) Common Carp (cm) Silver Barb (cm) Mrigal (cm) READ PADEK AIT SAO READ survival of Common Carp and Silver Barb was better than the other agencies (Table 11.13). But for the post stocking mortality of the Tilapia and flooding, survival of all species would have been best at READ nurseries. The low survival of AIT seed can be attributed to the small stocking size. Table 11.13: Mean fish seed survival (%) by species in READ, PADEK, AIT and SAO nurseries Project Tilapia Silver Carp Common Carp Silver Barb Mrigal READ PADEK AIT SAO ECONOMIC ANALYSIS Table shows that the cost of production per unit area was least, 97,990 Riel per 100 m 2, at Mr. Sot Sen s nursery because his fish seed was cheaper than the other farmers. Seed cost was the major investment cost, ranging from 68 80% of total investment cost. Mr. Chhum Try had the greatest income, 173,600 Riel per 100 m 2, because his larger-size fish had a price premium; he also made the best net profit per unit area of nursery pond at 53,680 Riel per 100 m 2. Mr. Sot Sen had the best return against investment, with a net profit percentage of 64%. Table shows that the price of fingerlings was the major investment cost for all four agencies, ranging from 51 87% of the total investment. Hapa depreciation was the second biggest cost for SAO nursery farmers. READ had the lowest production cost at 112,530 Riel per 100 m 2. However the income per unit area for PADEK and AIT was nearly double and treble respectively that of the READ nurseries. PADEK and AIT had incomes from fish seed sale of 343,440 Riel and 438,000 Riel per

7 m 2 respectively. PADEK had the best return against investment with a net percentage profit of 71%. READ s return against investment was the worst at 39%. Since READ had good fish survival and growth of fish, it can only be assumed that farmers from AIT and PADEK are able to sell their fingerlings at significantly higher prices than are READ nursery farmers. Table 11.14: Production cost, income and net profit of seed nursing in READ project area Item Ork Son Sot Sen Chhum Try Mean (Riel/100m 2 ) (Riel/100m 2 ) (Riel/100m 2 ) (Riel/100m 2 ) Fish seed (76%) 91,120 (68%) 66,750 (80%) 95,880 (75%) 84,580 Lime & fertilizer (7%) 8,000 (9%) 8,900 (7%) 8,000 (7%) 8,300 Feed (6%) 7,650 (5%) 5,090 (3%) 3,860 (5%) 5,530 Fuel (4%) 5,000 (10%) 10,000 (6%) 6,600 (6%) 7,200 Labor (3%) 3,500 (3%) 2,500 (2%) 2,500 (3%) 2,830 Hapa depreciation (4%) 4,440 (5%) 4,750 (3%) 3,080 (4%) 4,090 Total (100%) 119,710 (100%) 97,990 (100%) 119,920 (100%) 112,530 Income 145, , , ,730 Net profit 25,420 53,480 53,680 44,200 Net profit % Table 11.15: Mean production cost, income and net profit of seed nursing of different agencies Item READ PADEK AIT SAO (Riel/100m 2 ) (Riel/100m 2 ) (Riel/100m 2 ) (Riel/100m 2 ) Fish seed (75%) 84,580 (77%) 155,000 (87%) 240,000 (51%) 62,400 Lime & fertilizer (7%) 8,300 (4%) 7,600 (3%) 8,200 (7%) 8,280 Feed (5%) 5,530 (11%) 21,450 (3%) 8,770 (8%) 9,640 Fuel (6%) 7,200 (5%) 10,000 (3%) 9,000 (6%) 7,370 Labor (3%) 2,830 (2%) 4,270 (3%) 7,360 (2%) 2,440 Hapa depreciation (4%) 4,090 (2%) 3,040 (1%) 2,000 (26%) 31,670 Total (100%) 112,530 (100%) 201,360 (100%) 275,330 (100%) 121,800 Income 156, , , ,330 Net profit 44, , ,670 49,530 Net profit % CONCLUSIONS AND RECOMMENDATIONS Production by READ nursery farmers in terms of fish growth and survival compares well with PADEK, AIT Outreach and SAO nursery farmers. Despite this and having the lowest costing investment per unit area, READ nursery farmers are receiving significantly less net income per unit area and return to investment than AIT Outreach and PADEK nursery farmers. The READ nursery package may, however, still represent a viable low risk option for small-scale nursery farmers, who are unable to access formal credit. READ should consider recommending that nursery farmers increase both the stocking density of fish to fish m -2 and the sale price of fingerlings. 6. REFERENCES DoF, Cambodian National Fishery Statistics for Department of Fisheries, Phnom Penh. Figure 11.1: Photographs of the species studied (not to scale)

8 (Photos Aquaculture Indigenous Mekong Fish Species Cambodia Sub-Component) Trey Tilapia Tilapia Trey Carp Sar Silver Carp RtIq<in Trey Chhpin Trey Chpin (Siver Silver Barb) Barb Trey Carp India Mrigal Trey Carp Samanh Common Carp