Báo cáo nghiên cứu khoa học: Better Breeds of Common Carp (Cyprinus carpio L.) for Small-scale Fish Farmers (Milestone 4)

Ministry of Agriculture & Rural Development

Collaboration for Agriculture & Rural Development

002/04VIE Project

Better Breeds of Common Carp (Cyprinus carpio L.)

for Small-scale Fish Farmers

Milestone 4: On-farm Trials and Uptake of Improved Breeds of

Common Carp

Christopher M Austin1, Tuan Anh Pham2, Binh Thanh Thai2, Hung Quang Le2 1School of Science and Primary Industries, Charles Darwin University, Darwin Northern

Territory 0909, Australia 2Research Institute for Aquaculture No 1, Dinh Bang, Tu Son, Bac Ninh, Vietnam

October, 2007

Contents........................................................................................................... 2

List of Figures ................................................................................................. 3

List of Table .................................................................................................... 4

1. Introduction ................................................................................................ 6

2. Materials and methods............................................................................... 7

2.1. Experimental Design..................................................................................................7

2.2. Selection of common carp strains ..............................................................................8

2.3. Common carp rearing and experimental procedures .................................................9

2.4. Data collection and analysis.....................................................................................11

3. Results........................................................................................................ 14

3.1. Fingerling growth rate..............................................................................................14

3.2. Growth and survival of HP3 and LOC strains and effects of feed input .................14

3.3. Growth rate and survival of HP3, H3B and LOC strains ........................................17

3.4. Growth rate and survival for HP3, VNW and LOC Strains ....................................19

3.5. Growth rate and survival of HP3, H3B, VNW and LOC strains in low feed input

farms controlled for variation among farmer ponds ..................................................21

3.6. Common carp biomass production in farms stocked with three common carp strain

(HP3, H3B, LOC) ......................................................................................................23

3.7. Common carp biomass production comparing farms stocked with two common

carp strains (HP3 and LOC). ......................................................................................25

3.8. Demand of the improved common carp seed ..........................................................27

4. Conclusion and Recommendations......................................................... 29

Appendices .................................................................................................... 33

Reference ....................................................................................................... 34

List of Figures

Fig 2.1. Rice field used for farm trials in Yen Bai province.................................................9

Fig 2.2. Farmer’s pond in Thai Nguyen province.................................................................9

Fig 2.3. Measuring common carp. ......................................................................................11

Fig 2.4. Ethnic people harvesting common cap in rice field in Yen Bai province .............12

Fig 2.5. Harvesting common carp in pond in Thai Nguyen................................................13

Fig 2.6. A farmer is happy with common carp growth.......................................................13

Fig 3.1. Daily growth rate of HP3 and LOC common carp strains in each of 18 farms.....15

Fig 3.2. Example of relative growth of three strains of common carp in rice field in Yen

Bai province after six months of culture.................................................................18

Fig 3.3. Daily growth rate of HP3, H3B and LOC common carp strain in each of 11 farms

in Yen Bai and Thai Nguyen provinces..................................................................18

Fig 3.4. Daily growth rate of HP3, VNW and LOC common carp strain for a period of 10

months in each farm in Yen Bai and Thai Nguyen provinces. ...............................20

Fig 3.5. Daily growth rate of HP3, H3B, VNW and LOC common carp strains in 3 farms.

................................................................................................................................22

Fig 3.6. Common carp from HP3 strain after seven months of cultured in a high input feed

farm in Thai Nguyen province................................................................................23

Fig 3.7. Proportion of genetically improved common carp fry and fingerlings cultured in

Vinh Phuc, Thai Nguyen and Yen Bai provinces during 2004-2006. ....................29

List of Table

Table 2.1. Farms, pond type, and number of fish stocked of each strain (some farms were

remove from the data set because fish escaped during flooding). ..........................10

Table 2.2. Data analyses for common carp culture farm trails ...........................................13

Table 3.1 Mean (± SD) of body length and weight of fingerling carp after 60 days of

nursing ....................................................................................................................14

Table 3.2. ANOVA table testing for differences in daily growth rate in relation to the

effects of common carp strain (HP3 and LOC) and type of feed input. .................15

Table 3.3. Daily growth rate of HP3 and LOC common carp strain for period of 10 months

in 18 farms in two type of feeding regimes in Yen Bai and Thai Nguyen provinces.

Superscripts indicate significant differences among groups based on Tukey’s test.

................................................................................................................................15

Table 3.4. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strain (HP3 and LOC) and type of feed input. .................................16

Table 3.5. Survival rate of HP3 and LOC common carp strains grown for a period of 10

months in 18 farms with two types of feeding rates in Yen Bai and Thai Nguyen

provinces. Superscripts indicate significant differences among groups based on

Tukey’s test.............................................................................................................16

Table 3.6. ANOVA table testing for differences in daily growth rate in relation to the

effects of common carp strain (HP3, H3B and LOC).............................................17

Table 3.7. Daily growth rate of HP3, H3B and LOC common carp strains grown for a

period of 10 months in 11 farms in Yen Bai and Thai Nguyen provinces.

Superscripts indicate significant differences among groups based on Tukey’s test.

................................................................................................................................17

Table 3.8. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strains (HP3, H3B and LOC). ..........................................................19

Table 3.9. ANOVA table testing for differences in daily growth rate in relation to the

effects of common carp strain (HP3, VNW and LOC)...........................................19

Table 3.10. Daily growth rate of HP3, VNW and LOC common carp strains grown for a

period of 10 months in 5 farms in Yen Bai and Thai Nguyen provinces.

Superscripts indicate significant differences among groups based on Tukey’s test.

................................................................................................................................20

Table 3.11. ANOVA table testing for differences in survival rate in relation to the effects

of common carp strains (HP3, VNW and LOC).....................................................21

Table 3.12. ANOVA table testing for differences in daily growth rate in relation to the

effects of common carp strain (HP3, H3B, VNW and LOC) .................................21

Table 3.13. Daily growth rate of HP3, H3B, VNW and LOC common carp strains for

period of 10 months in 3 farms in Yen Bai and Thai Nguyen provinces.

Superscripts indicate significant differences among groups based on Tukey’s test.

................................................................................................................................22

Table 3.14. ANOVA table testing for differences in survival rate in relation to the effects

of common carp strains (HP3, H3B, VNW and LOC) and culture types (low and

high feed input). ......................................................................................................23

Table 3.15. Biomass of common carp strains in 11 farms with 3 strains (HP3, H3B and

LOC) and cultured for 300 days in Yen Bai and Thai Nguyen provinces..............24

Table 3.16. ANOVA analyses of biomass of HP3, H3B, and LOC common carp strains.25

Table 3.17. ANOVA analysis of biomass of HP3 and LOC common carp strains. ...........25

Table 3.18. Biomass of common carp strains in 18 farms with 2 strains (HP3 and LOC)

cultured for 300 days. Superscripts indicate significant differences among groups

based on Tukey’s test..............................................................................................26

Table 3.19. Biomass of HP3 and LOC common carp strains grown for a period of 10

months in 18 farms with two types of feed input in Yen Bai and Thai Nguyen

provinces.................................................................................................................27

Table 3.20. Number of hatcheries and fry nursing farmers in 3 provinces. .......................27

Table 3.21. Number of common carp fry produced in five hatcheries in Thai Nguyen, Yen

Bai and Vinh Phuc provinces in 2006.....................................................................28

Table 3.22. Proportion of fry produced from genetically improved common carp lines in

five hatcheries in Thai Nguyen, Yen Bai, and Vinh Phuc provinces in 2006. .......28

1. Introduction

In Vietnam aquaculture plays a very important role in economic development and food

security for small scale farmers and contributes 35% of Vietnamese protein consumption.

Aquaculture production is increasing at rate of 10% per year and contributes significantly

to the country’s export income (MOFI, 2007).

Common carp is one of the most popular freshwater aquaculture species in Vietnam and is

cultured in pond, cages, reservoir and rice field for household consumption and income

generation. A recent survey of 133 carp farmers indicated that pond and rice field

production are the preferred form of culture systems (98%) with the pond culture the most

common (Austin et al., 2007a). Most farmers culture common carp with up to 8 other fish

species, both indigenous (silver carp, black carp) and exotic (silver grass carp, bighead,

rohu, mrigal, pirapitinga, Tilapia). In polyculture ponds, common carp is the predominate

species making up 30.1% of the biomass based on a recent survey (Austin et al., 2007a).

The level of culture intensity for common carp varies from small scale extensive farming,

with fish deriving all their nutrition from natural pond productivity, through semi-

intensive farming using fertilization from organic material such as bran, agriculture by-

products and household wastes to high intensive culture system with high stocking

densities and the use of manufactured fish foods. Semi-intensive culture systems are the

most popular in Vietnam using ponds or a combination of ponds and rice field cultivation

(Austin et al., 2007a).

There are many factors that affect production and yield of farmed fish species, including

seed (fry and fingerlings) quality, feed type and rate, fertilisation and pond management,

including water exchange. Of these, seed quality, which is directly related to the genetic

quality of the broodstock used to produce the fry and fingerlings, has been identified as

being of major concern to researchers (Thai et al., 2006; 2007), but which is not generally

understood by farmers to be a potential issue affecting farm productivity (Austin et al.,

2007a).

In Vietnam there are many different local varieties of common carp that have been used

by farmers but they usually have small size and low growth rate (Tran, 1983). Over recent

times the Research Institute for Aquaculture No.1 (RIA-I) has bred genetically improved

common carp strains to enhance the productivity of small scale fish farms that utilise this

species. This program has used crossbreeding and mass and family selection

methodologies to produce genetically improved strains and is considered to have achieved

an average increase of 5% in growth rate per generation over a number of generations

(Thien and Thang, 1992). However, all the selective breeding and associated growth trials

have been conducted in research ponds, often without the availability of unselected lines

as control populations for comparative studies.

As a consequence, on-farm growth trials of different strains were undertaken to allow for a

more effective analysis of carp growth under environments directly relevant to small scale

carp farmers and as a strategy to encourage uptake by farmers of genetically improved

strains. This report presents, firstly, a report on the statistical analysis of growth and

production of different common carp strains in small scale farmer ponds in Yen Bai and

Thai Nguyen provinces. The farmers participating in this research project included those

using both pond and rice field culture from mostly highland environments. All farmers

had previously participated in the socio-economic survey and one of two workshops on

fish breeding and genetic improvement conducted as part of this project. Secondly, a

survey of the uptake of improved breeds by producers is presented.

2. Materials and methods

2.1. Experimental Design

The original objective of the on-farm trials was to compare a genetically improve carp

strain and a local strain communally reared in six ponds owned by different farmers. With

additional support from the Research Institute of Aquaculture No. 1 (RIA1), the

experimental objectives were scaled up to include 37 separate farmers and four strains.

The majority (34) of farmers used ponds as their culture systems with six farmers using

rice field systems, which reflects the proportion of these different farming systems in these

provinces based on the socio-economic survey (Austin et al., 2007a) (Fig 2.1&2.2). Farms

were classified according to their levels of feed inputs as either high or low to determine if

this important management aspect influenced the relative performance of the different

carp strains. Farmers who did not provide food more than once per month were classified

as having “Low” input pond systems and those who fed at least once per week or more

frequently were classified as having “High” input pond systems. The experiment was

conducted over a 12 months period from March 2006 to March 2007, which included

spawning and fry rearing March – May, 2006 and fingerling grow out May 2006 to March

2007, which largely coincides with the normal carp farming culture cycle. The trials were

conducted in pond systems owned by 20 households in each of the Thai Nguyen and Yen

Bai provinces. Representatives of these households were interviewed for the socio-

economic survey and participated in one of the farmer workshops on fish breeding and

selection held as part of this project.

As described in more detail below the experimental design could not be achieved due to

differential reproduction and survival of fry. Thus different farms were stocked with

different numbers of strains and in varying combinations. Further, fish could not be

harvested from several farms due to flooding and other management problems. Appendix

1 lists the farms that participated in the project, and details of their culture systems and

fish that were stocked and if data collection at harvest was possible.

2.2. Selection of common carp strains

Fours common carp strains were used for growth trials and included one strain (HP3)

recently produced through hybridization between the three blood Hungarian strain and a

recently imported pure line of Hungarian carp, the three blood Hungarian strain (H3B), an

unselected Vietnamese strain (VNW) and a locally available strain (LOC) produced from

broodstock available from the Yen Bai provincial hatchery. Genetic analysis of this strain

(Thai et al., 2006: 2007) indicates it represented a mixture of Indonesian, Hungarian and

Vietnamese strains with the latter strain predominating.

.

Fig 2.1. Rice field used for farm trials in Yen Bai province

Fig 2.2. Farmer’s pond in Thai Nguyen province

2.3. Common carp rearing and experimental procedures

Common carp breeding was undertaken at the National Broodstock Centre Hai Duong.

Broodstock of each experimental strain were induced to breed on the same day, using

standard practices for gamete stripping and fertilization (Thai and Ngo, 2004). Between 10

-12 families of fish were obtained from each strain. After fertilization eggs produced from

different families of the one strain were pooled and raised in 200l upwelling incubators.

After 4-5 days when larvae had reached 8-12 mm they were transferred to four ponds and stocked at a rate of 100 larvae/m2 and grown for a period of two months. Every effort was

made to keep the conditions under which the fry and fingerlings of each strain were raised

as similar as possible, especially in relation to stocking density and feeding regime. When

the fingerlings had reached of 3-5g, they were tagged by using Coded Wire Tag (CWT).

The strains of common carp lines were marked by placing the CWTs on different

locations on the body. The tagged fish were stocked into 40 ponds or pond-rice field

systems over a two day period. Communally stocked fish were in equal proportions with

the exception of three ponds. The details of the fish stocked in farms is given Table 2.1.

Table 2.1. Farms, pond type, and number of fish stocked of each strain (some farms were remove

from the data set because fish escaped during flooding).

Strain and No of fish stocked

Farm

Feed

100

Thai Nguyen Thai Nguyen

100 120 100 100 100 113 113 80

50 80

100 113 113 100 60 100 113 113 75 150 80 90 100 75

Yen Bai Hoan Ly Yen Bai Thuan Yen Bai Tap Tuan Chung Yen Bai Yen Bai Lien Yen Bai Hom Yen Bai Tho Thai Nguyen Dieu Thai Nguyen Ha Thai Nguyen Lieu Thai Nguyen Canh Thai Nguyen Luat Yen Bai Nhan Truong Thai Nguyen Thai Nguyen Que Thai Nguyen Vinh Ke Thai Nguyen Thong Yen Bai Lich Trung

Provinces Culture Area (m2) 1000 800 1000 800 1000 1000 1500 800 450 600 1500 1000 400 1000 1500 500 1000 800 550 1000 500 400

systems Ricefield Pond Pond Pond Pond Pond Ricefield Ricefield Pond Pond Pond Pond Pond Pond Pond Pond Pond Pond Pond Pond Pond Pond

Thai Nguyen Thai Nguyen

input HF LF LF HF LF HF LF LF HF LF LF LF HF LE LE HF LF LF LF LF LF LF

HP3 H3B VNW LOC Total 300 100 100 240 120 120 300 100 100 240 120 300 100 100 300 100 450 113 113 240 80 150 75 200 100 450 113 113 300 55 145 120 60 300 100 100 450 113 113 150 75 300 100 240 80 180 90 300 100 100 150 75 120 60

HF: High feeding rate LF: Low feeding rate.

Each farm pond or rice field was stocked at a rate of 0.3 fish/m2 and was classified as

either “Low Feed” or “High Feed” based on the level of food inputs into the ponds. Rice

field systems fed less than once per week were classified as low input systems and more

than once per week as high input.

All experimental ponds and rice fish fields were managed by farmers. Fish in ponds and

rice fields were fed by available foods from farmers’ households such as rice bran, corn

and cassava. A log book was provided to each farmer to keep a record of food inputs into

their experimental pond and other relevant information and this information was used to

classified ponds into high and low feed input. The farmers were visited on a monthly basis

by project staff to assist in record keeping (Fig 2.3).

Fig 2.3. Measuring common carp.

2.4. Data collection and analysis

Inequalities in fry weight among strains after the three month nursing period was tested by

weighing a sample of 30 individuals to the nearest 0.1 g and analysed using a one –way

ANOVA. Prior to this analysis the FMax test was used to determine if variances amongst

strains were homogenous.

Pond trials were conducted for 300 – 330 days. Fish were harvesting by draining and by

netting. Data from were collected as fish wet weight to the nearest 0.1 g and length (snout

– caudal) measured to the nearest mm (Fig 2.4, 2.5 & 2.6). Fish were allocated to strain

based on the identification of the position of the CWT using a detector scanner (North

West Marine technology, Shaw Island, WA, American). To compare growth between

strains, fish weights were converted to daily growth rate (DGR) after first subtracting the

mean fingerling weight for that strain.

The appropriate statistical procedure for the experimental design for analyzing for

differences in growth rate is a three-way ANOVA with nesting. The first level of the

analysis allows partitioning of variance due to Feed Input as either low (LF) or high (HF),

the second level is Farmer, which is nested within level 1 and the third level is Fish Strain.

Due to the unequal numbers fry available for each of the four carp strains and their

stocking in different combinations into farms and the unavailability of data from a number

farms, several kinds of ANOVA were conducted. The number of farms with different

combinations of stocked strains is given in Table 2.2 together with the type of ANOVA

conducted.

Fig 2.4. Ethnic people harvesting common cap in rice field in Yen Bai province

Fig 2.5. Harvesting common carp in pond in Thai Nguyen

Fig 2.6. A farmer is happy with common carp growth

Table 2.2. Data analyses for common carp culture farm trails

Strains

Farm input

Type of analysis

Three way Anova

(HP3,

LOC)

Low High Total 18

Two way Anova

(HP3, H3B,

LOC)

Two way Anova

(HP3,

VNW, LOC)

Two way Anova

(HP3, H3B, VNW, LOC)

Percentage of recovered fish and harvested fish biomass of each common carp strain were

analyzed as a 2-way ANOVA. The biomass of fish harvested in ponds with unequal

stocking rates was adjusted to the average stocking rate to allow for statistical comparison.

All analyses were conducted using the Excel and SPSS software packages.

3. Results

3.1. Fingerling growth rate

The average weight of common carp fingerlings after 60 days of nursing was 3.18 g. The

average weight of each common carp strain is given in Table 3.1. However, the difference

in body weigh among strains was not significantly different (P>0.05).

Table 3.1 Mean (± SD) of body length and weight of fingerling carp after 60 days of nursing

Carp strain Length (cm) Weight (g)

HP3 4.72 ± 0.70 3.38 ± 1.50

H3B 4.57 ± 0.56 2.82 ± 1.66

VNW 5.36 ± 1.28 4.21 ± 2.84

LOC 4.27 ± 0.74 2.29 ± 1.32

Total 4.73 ± 0.82 3.18 ± 1.83

3.2. Growth and survival of HP3 and LOC strains and effects of feed input

Growth rate for the HP3 and LOC strains were compared in 18 farms which included both

low and high feed input systems. Significant differences were observed for all factors and

for the interaction between production systems and strain (Table 3.2) (P<0.01). The mean

daily growth rate of HP3 strain (0.48g) was 60% higher than that of local strain (LOC)

(0.30g) (Table 3.3). Daily growth rate of each fish farm is present in Fig 3.1.

Table 3.2. ANOVA table testing for differences in daily growth rate in relation to the effects of

common carp strain (HP3 and LOC) and type of feed input.

F 329.90 213.32 6728.53 142.42 300.13 278.62 166.26

Sig. 0.00 0.00 0.00 0.00 0.00 0.00

4.52 9.52 9.49 5.27 0.03

Source Corrected Model Intercept Farm Strain Feed input Strain * Feed input Error Total Corrected Total

Type III Sum of Squares 209.18 213.32 76.76 9.52 9.49 5.27 25.81 367.36 234.99

df Mean Square 10.46 20 1 17 1 1 1 814 835 834

Table 3.3. Daily growth rate of HP3 and LOC common carp strain for period of 10 months in 18

farms in two type of feeding regimes in Yen Bai and Thai Nguyen provinces. Superscripts

indicate significant differences among groups based on Tukey’s test.

Strain

Feed input

HP3

High 1.13 ± 0.03c 0.79 ± 0.04d

Low 0.22 ± 0.02a 0.16 ± 0.02b

LOC

3.00

HP3

2.50

LOC

2.00

) g (

1.50

G R D

1.00

0.50

0.00

Luat

Vinh

Tuan

Lieu

Dieu

Que

Lich

Lien

Hom Nhan Thong Thuan Truong Hoan

Tap Chung

Low feeding rate

High feeding rate

Farm

Fig 3.1. Daily growth rate of HP3 and LOC common carp strains in each of 18 farms.

This last finding is particularly significant as it indicates that while there is a significant

difference among strains, this difference is greatly diminished in production systems with

low feed inputs. Table 3.3 gives the average daily growth rate for the 2 strains in each

system and it can be seen there is only a 0.06g difference in average daily growth in low

feed input systems compared with a 0.36 in high input system.

The results from an analysis of survival rate of two strains are shown in Table 3.4 and

Table 3.5. There is a significant difference in survival rate between low and high feed

input farms but no significant difference between strains. The survival rate of HP3 and

LOC strains is 24.77% and 22.76% respectively and it is 62% higher in High feed input

ponds compared to Low feed input ponds.

Table 3.4. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strain (HP3 and LOC) and type of feed input.

F Sig 14.88 0.00 1641.80 0.00 3.03 0.10 9.44 0.00 0.27 0.61

Source Corrected Model Intercept Strain Feed input Strain * Feed input Error Total Corrected Total

Type III Sum of Squares 3366.45 19547.55 36.13 772.99 3.18 190.50 23894.81 3556.95

df Mean Square 177.18 19 19547.55 1 36.13 1 772.99 1 3.18 1 16 11.91 36 35

Table 3.5. Survival rate of HP3 and LOC common carp strains grown for a period of 10 months

in 18 farms with two types of feeding rates in Yen Bai and Thai Nguyen provinces. Superscripts

indicate significant differences among groups based on Tukey’s test.

Feed input

Std Min Max

0.86

11.72

29.33

Low

6.31

14.17

High

Mean 21.29a 32.44b 26.90a

3.58

12.95

Total

62.00 45.67

3.3. Growth rate and survival of HP3, H3B and LOC strains

Growth data from three strains, HP3, H3B and LOC were compared in 11 farms which

included 10 low and 1 high feed input systems. Significant differences were observed for

strain and farmer as presented Table 3.6. Table 3.7 gives the average growth rate for the 3

strains. The effect of the level of feed input could not be tested statistically due lack of

replicates. The differences between strains can be seen from Figure 3.2 and Table 3.7. The

daily growth rate of common carp in each farm is presented in Fig 3.3. Each strain was

significantly different on the basis of Tukey’s test with HP3>H3B>LOC.

Table 3.6. ANOVA table testing for differences in daily growth rate in relation to the effects of

common carp strain (HP3, H3B and LOC).

Sig. 0.00 0.00 0.00 0.00

Source Corrected Model Intercept Strain Farm Error Total Corrected Total

Type III Sum of Squares 60.13 49.36 1.84 58.78 9.86 133.38 69.99

F df Mean Square 4.63 13 387.22 49.36 4132.25 1 77.08 0.92 2 447.32 5.34 10 825 0.01 839 838

Table 3.7. Daily growth rate of HP3, H3B and LOC common carp strains grown for a period of

10 months in 11 farms in Yen Bai and Thai Nguyen provinces. Superscripts indicate significant

differences among groups based on Tukey’s test.

Strain

Std

Min

Max

0.34

0.05

1.90

HP3

301

H3B

282

0.27

0.04

1.51

Mean 0.33a 0.26b 0.23c

LOC

256

0.23

0.02

0.27d

Total

839

0.28

0.03

1.05 1.49

HP3

LOC

H3B

Fig 3.2. Example of relative growth of three strains of common carp in rice field in Yen Bai

province after six months of culture.

1.400

HP3

H3B

1.200

LOC

1.000

0.800

) g (

0.600

G R D

0.400

0.200

0.000

Luat

Vinh Tuan

Lieu Que

Lien Hoan Nhan Thuan Thong

Farm

Fig 3.3. Daily growth rate of HP3, H3B and LOC common carp strain in each of 11 farms in Yen

Bai and Thai Nguyen provinces.

ANOVA analyses of survival rate of common carp showed that there was a significant

difference between farms, while survival rate between common carp strains was not

different (Table 3.8). The average survival rate of HP3, H3B and LOC was 24.28%,

25.78%, and 23.45% respectively.

Table 3.8. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strains (HP3, H3B and LOC).

F 299.30 15.10 17183.84 866.98 349.90 17.65 1.27

Sig. 0.00 0.00 0.00 0.30

25.09 19.82

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 3890.87 17183.84 3848.88 50.18 376.59 23859.09 4267.46

df Mean Square 13 1 11 2 19 33 32

3.4. Growth rate and survival for HP3, VNW and LOC Strains

Growth data from three strains, HP3, VNW and LOC were compared in 5 farms which

included 4 low and 1 high feed input systems. Significant differences were observed for

both strain and farmer factors as presented Table 3.9. Table 3.10 gives the average growth

rate for the 3 strains. While the effect of production system could not be tested statistically

due to lack of replicates for this effect and the differences between strains and farms can

be seen from Figure 3.4. Each strain was significantly different on the basis of Tukey’s

test with HP3>VNW>LOC.

Table 3.9. ANOVA table testing for differences in daily growth rate in relation to the effects of

common carp strain (HP3, VNW and LOC).

F 55.05 17.22 1381.20 62.84 43.40

Sig. 0.00 0.00 0.00 0.00

0.78 0.54 0.01

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 4.12 17.22 3.13 1.08 3.74 25.74 7.86

df Mean Square 0.69 6 1 4 2 300 307 306

Table 3.10. Daily growth rate of HP3, VNW and LOC common carp strains grown for a period

of 10 months in 5 farms in Yen Bai and Thai Nguyen provinces. Superscripts indicate significant

differences among groups based on Tukey’s test.

Strain

Std

Min

Max

0.20

0.10

1.50

HP3

112

VNW

0.12

0.03

0.66

LOC

0.10

0.02

Mean 0.31a 0.22b 0.18c 0.24c

0.14

0.05

Total

307

0.78 0.98

0.60

HP3

0.50

VNW

0.40

LOC

) g (

0.30

G R D

0.20

0.10

0.00

Lien

Nhan

Chung

Hom

Farm

Fig 3.4. Daily growth rate of HP3, VNW and LOC common carp strain for a period of 10 months

in each farm in Yen Bai and Thai Nguyen provinces.

The results of the survival rate of three common carp strains (HP3, VNW and LOC)

showed no significant differences between farms (Table 3.11). Although survival rate of

HP3 was the highest (20.57%) there had no significant difference comparing with other

two strains (VNW = 17.98% and LOC = 18.49%).

Table 3.11. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strains (HP3, VNW and LOC).

F 2.28 850.77 2.68 1.49

Sig. 0.14 0.00 0.11 0.28

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 87.19 5417.29 68.18 19.01 50.94 5555.42 138.13

df Mean Square 14.53 6 5417.29 1 17.04 4 9.51 2 8 6.37 15 14

3.5. Growth rate and survival of HP3, H3B, VNW and LOC strains in low feed input

farms controlled for variation among farmer ponds

Growth data from all four strains, HP3, H3B, VNW and LOC were compared in 3 low

input farms in which they were raised communally. Significant differences were observed

for both strain and farmer as presented Table 3.12. Table 3.13 gives the average growth

rate for the 4 strains. Post hoc tests indicated significant differences among strains with

HP3 > H3B = VIET > LOC. Daily growth rate of each strain and farm are presented in Fig

3.5.

Table 3.12. ANOVA table testing for differences in daily growth rate in relation to the effects of

common carp strain (HP3, H3B, VNW and LOC)

F 135.15 3480.33 203.09 91.25

Sig. 0.00 0.00 0.00 0.00

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 1.53 7.89 0.92 0.62 0.55 10.65 2.08

df Mean Square 0.31 5 7.89 1 0.46 2 0.21 3 242 0.00 248 247

Table 3.13. Daily growth rate of HP3, H3B, VNW and LOC common carp strains for period of 10

months in 3 farms in Yen Bai and Thai Nguyen provinces. Superscripts indicate significant

differences among groups based on Tukey’s test.

Strain

Std

Min

Max

HP3

0.08

0.10

0.46

H3B

0.09

0.04

0.38

VNW

0.07

0.03

0.38

LOC

0.06

0.02

Mean 0.26a 0.17b 0.17b 0.13c 0.18C

Total

248

0.08

0.05

0.24 0.37

0.40

HP3

0.35

H3B

0.30

VNW

0.25

LOC

) g (

0.20

G R D

0.15

0.10

0.05

0.00

Lien

Nhan

Farm

Fig 3.5. Daily growth rate of HP3, H3B, VNW and LOC common carp strains in 3 farms.

The results of survival rate comparisons among four common carp strains (HP3, H3B,

VNW and LOC) are showed in Table 3.14. There are significant differences between fish

survival rate among farms (P<0.05) with survival rate of fish in the farms ranged from

20.94 to 16.81 %. There was no significant differences in survival rate between common

carp strains (P>0.05).

Table 3.14. ANOVA table testing for differences in survival rate in relation to the effects of

common carp strains (HP3, H3B, VNW and LOC) and culture types (low and high feed input).

F 4.33 991.99 6.82 2.68

Sig. 0.05 0.00 0.03 0.14

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 90.87 4161.47 57.19 33.68 25.17 4277.52 116.04

df Mean Square 18.17 5 4161.47 1 28.60 2 11.23 3 6 4.20 12 11

Fig 3.6. Common carp from HP3 strain after seven months of cultured in a high input feed farm

in Thai Nguyen province.

3.6. Common carp biomass production in farms stocked with three common carp

strain (HP3, H3B, LOC)

Common carp production was compared for 3 strains in 11 farms. Biomass of common

carp from 11 farms is presented in Table 3.23. Significant differences were observed

between farms and strains of common carp (Table 3.24). The pair-wise comparison

indicated difference in biomass of common carp between farms and between strains using Tukey’s test. Biomass of three common carp strains ranged from 3.16g/m2 (LOC) to 4.80g/m2 (HP3).

Table 3.15. Biomass of common carp strains in 11 farms with 3 strains (HP3, H3B and LOC) and

cultured for 300 days in Yen Bai and Thai Nguyen provinces.

Stocking

Harvesting

Farm

Hoan

Area Culture Strains (m2) systems 1000

Thuan

1000

Tuan

1000

Lieu

1000

Luat

1000

Que

1000

Vinh

800

Thong

1000

Lien

1500

Nhan

1500

HF HP3 100 H3B 100 LOC 100 LF HP3 100 H3B 100 LOC 100 LF HP3 100 H3B 100 LOC 100 LF HP3 145 H3B 55 LOC 100 LF HP3 100 H3B 100 LOC 100 LF HP3 100 H3B 50 LOC 150 80 LF HP3 80 H3B 80 LOC LF HP3 100 H3B 100 LOC 100 LF HP3 113 H3B 113 LOC 113 LF HP3 113 H3B 113 LOC 113 LF HP3 113 H3B 113 LOC 113

N Weight (g) 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.80 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29 3.38 2.82 2.29

NWeight (g) Sur (%) DGR 1.28 51 0.97 62 0.83 56 0.32 20 0.28 19 0.23 19 0.20 30 0.17 26 0.17 29 0.21 40 0.24 10 0.15 12 0.10 15 0.07 14 0.05 17 0.20 36 0.19 11 0.18 33 0.21 20 0.18 15 0.16 22 0.16 22 0.15 21 0.12 22 0.28 25 0.20 20 0.14 30 0.34 20 0.27 21 0.18 22 0.20 21 0.07 16 0.05 19

385.08 292.33 249.49 97.43 82.82 67.90 59.87 51.43 49.89 61.88 70.55 44.82 28.61 22.45 16.10 59.35 56.74 53.68 62.73 53.78 46.51 49.00 44.00 35.67 83.96 58.72 41.66 102.67 79.93 54.24 59.88 20.61 15.66

51.00 62.00 56.00 20.00 19.00 19.00 30.00 26.00 29.00 27.27 19.00 11.72 15.00 14.00 17.00 36.00 21.00 22.00 25.00 18.89 27.50 22.00 21.00 22.00 22.12 17.70 26.55 17.70 18.58 19.47 18.58 14.16 16.81

Biomass Adjusted (g/m2) 29.72 27.45 20.96 2.92 2.36 1.94 2.69 2.01 2.17 2.53 2.01 0.79 0.64 0.47 0.41 3.20 1.79 1.77 2.35 1.52 1.92 1.62 1.39 1.18 2.79 1.56 1.66 2.73 2.23 1.58 1.67 0.44 0.40

(g/m2) 19.30 17.84 13.74 1.61 1.29 1.06 1.46 1.05 1.22 1.96 0.58 0.30 0.09 0.03 0.05 1.80 0.46 1.43 1.23 0.73 1.05 0.74 0.64 0.56 1.14 0.57 0.66 1.11 0.91 0.62 0.58 0.01 0.03

Table 3.16. ANOVA analyses of biomass of HP3, H3B, and LOC common carp strains

Sig 0.00 0.00 0.00 0.02

Source Corrected Model Intercept Farm Strain Error Total Corrected Total

Type III Sum of Squares 1634.65 519.00 1619.77 14.88 33.24 2186.89 1667.90

df Mean Square F 81.95 136.22 12 519.00 312.23 1 97.45 161.98 10 4.48 7.44 2 20 1.66 33 32

3.7. Common carp biomass production comparing farms stocked with two common

carp strains (HP3 and LOC).

ANOVA analysis of biomass of common carp showed that there were significant

differences in biomass between farms, feed input, and the 2 strains (Table 3.25). The

biomass of common carp in two feed input systems are given in Table 3.26 and Table

3.27. The average common carp biomass for each strain in both high and low feed input

systems is given in Table 3.27.

Table 3.17. ANOVA analysis of biomass of HP3 and LOC common carp strains.

F 36.58 725.34 17.08 7.24 45.84 1.81

Sig 0.00 0.00 0.00 0.23 0.00 0.20

Source Corrected Model Intercept Farm Strain Feed input Strain * Feed input Error Total Corrected Total

Type III Sum of Squares 1416.77 1478.65 557.10 14.75 844.86 3.69 32.62 2198.60 1449.39

df Mean Square 19 74.57 1478.65 1 34.82 16 1 14.75 844.86 1 3.69 1 16 2.04 36 35

Table 3.18. Biomass of common carp strains in 18 farms with 2 strains (HP3 and LOC) cultured

for 300 days. Superscripts indicate significant differences among groups based on Tukey’s test.

Stocking

Harvesting

Farm

Hoan

Area Culture Strains (m2) systems 1000

HF HP3

Thuan

1000

LF HP3

Tap

800

HF HP3

Tuan

1000

LF HP3

Chung

1000

HF HP3

Lien

1500

LF HP3

Hom

800

Dieu

600

LF HP3 LOC LF HP3

1500

LF HP3

Lieu

1000

LF HP3

Luat

1000

LF HP3

Nhan

1500

LF HP3

Truong

500

HF HP3 LOC LF HP3

Que

1000

Vinh

800

550

LF HP3 LOC LF HP3 LOC LF HP3

Thong

1000

Lich

500

N Weight (g) 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29 3.38 2.29

100 LOC 100 100 LOC 100 120 LOC 120 100 LOC 100 100 LOC 100 113 LOC 113 80 80 100 LOC 100 113 LOC 113 145 LOC 100 100 LOC 100 113 LOC 113 75 75 100 LOC 150 80 80 90 90 100 LOC 100 75 75

LF HP3 LOC

N Weight (g) Sur (%) DGR 51.00 1.28 51 56.00 0.83 56 20.00 0.32 20 19.00 0.23 19 14.17 2.52 17 25.00 1.55 30 30.00 0.20 30 29.00 0.17 29 18.00 0.56 18 19.00 0.33 19 22.12 0.28 25 26.55 0.14 30 24.00 0.22 19 21.00 0.19 16 22.00 0.32 22 23.00 0.12 23 17.70 0.34 20 19.47 0.18 22 27.27 0.21 40 11.72 0.15 12 15.00 0.10 15 17.00 0.05 17 18.58 0.20 21 16.81 0.05 19 29.33 0.67 22 36.00 0.52 27 36.00 0.20 36 22.00 0.18 33 25.00 0.21 20 27.50 0.16 22 22.22 0.21 20 25.56 0.29 23 22.00 0.16 22 22.00 0.12 22 26.67 0.19 20 29.33 0.15 22

385.08 249.49 97.43 67.90 756.38 465.74 59.87 49.89 166.64 98.03 83.96 41.66 64.88 58.09 95.20 37.40 102.67 54.24 61.88 44.82 28.61 16.10 59.88 15.66 200.71 156.85 59.35 53.68 62.73 46.51 61.88 87.15 49.00 35.67 57.99 44.39

Biomass Adjusted (g/m2) 29.72 21.15 2.92 1.94 16.07 17.47 2.69 2.17 4.50 2.79 2.79 1.66 2.34 1.83 3.14 1.29 2.73 1.58 2.53 0.79 0.64 0.41 1.67 0.40 8.83 8.47 3.20 1.77 2.35 1.92 2.06 3.34 1.62 1.18 2.32 1.95

(g/m2) 19.30 13.74 1.61 1.06 15.57 17.12 1.46 1.22 2.66 1.63 1.14 0.66 1.22 0.99 2.93 1.05 1.11 0.62 1.96 0.30 0.09 0.05 0.58 0.03 8.32 8.13 1.80 1.43 1.23 1.05 1.70 3.27 0.74 0.56 1.81 1.61

Table 3.19. Biomass of HP3 and LOC common carp strains grown for a period of 10 months in

18 farms with two types of feed input in Yen Bai and Thai Nguyen provinces.

Strains

Feed input

HP3

High (g/m2) 14.78 ± 2.15b 12.47 ± 2.15b

Low (g/m2) 2.36 ± 1.15a 1.59 ± 1.15a

LOC

3.8. Demand of the improved common carp seed

A survey on demand for genetically improved common carp strain was conducted in three

provinces (Yen Bai, Thai Nguyen and Vinh Phuc) which have a high level of common

carp aquaculture. In these provinces common carp are cultured mostly in two different

farming systems consisting of ponds and flooded rice fields. The provinces differ in that

Yen Bai is a mountainous region, Thai Nguyen is partly mountainous with midlands while

Vinh Phuc is a delta area. A total of 25 common carp hatcheries and nursery producers

were surveyed. Details of interviewees are presented in Table 3.30.

Table 3.20. Number of hatcheries and fry nursing farmers in 3 provinces.

Provinces

Interviewee

Hatchery producer Nursery farmer

Yen Bai

Thai Nguyen

Vinh Phuc

Total

The results of the survey showed the number of common carp seed produced was highly

variable among fish hatcheries. The proportion of common carp produced ranged from

10.0% to 66.7% with an average of 37.4% of the total freshwater fish species produced

(Table 3.31). Most of hatcheries surveyed have produced both local (VNW) and

genetically improved common carp (three blood lines) (Table 3.32). It can be seen from

Table 3.32 the proportion of genetically improved common carp produced in hatcheries

ranged from 16.7% to 100% and the average proportion of improved genetically common

carp was 48.7%.

Table 3.21. Number of common carp fry produced in five hatcheries in Thai Nguyen, Yen Bai

and Vinh Phuc provinces in 2006.

Hatchery

No of fry (x 1000)

No of common carp fry (x 1000)

Proportion of carp fry (%)

Dong Ly

1,200

500

41.67

Van Chan

60,000

30,000

50.00

Phu Binh

120,000

24,000

20.00

Cu Van

30,000

20,000

66.67

Vu Di

120,999

12,000

9.92

Total

332,199

86,500

26.04

Table 3.22. Proportion of fry produced from genetically improved common carp lines in five

hatcheries in Thai Nguyen, Yen Bai, and Vinh Phuc provinces in 2006.

Hatchery

Province

No of carp fry

No of Local strain

Improved strain

Propotion of improved strain

(x 1000)

(%)

Dong Ly

Yen Bai

500

100.00

Van Chan Yen Bai

30,000

25,000

5,000

16.67

Phu Binh

Thai Nguyen

24,000

9,600

40.00

Cu Van

Thai Nguyen

20,000

100.00

Vinh Phuc

Vu Di

12,000

5,000

7,000

58.33

Total

86,500

54,000

42,100

48.67

Hybrid (Hungary x Vietnamese) and stocks derived from the genetically improved three

blood lines (Hungarian, Vietnamese and Indonesian) with faster growth performance are

preferred by most of the nursery farmers interviewed in three provinces. However, many

of the nursery farmers are not confident in identifying differences between hybrid and

other genetically improved and local Vietnamese strains. The main basis for determining

the quality of common carp seed is the perceived reputation of the hatchery based on the

farmers evaluation of the survival and growth performance of their fish in grow-out

systems. The results of a 2006 survey of 20 carp nursery farmers indicated that 95% of

farmers cultured genetically improved strains.

Based on data collected in earlier surveys it can be seen that demand for genetically

improved common carp by nursery farmers is increasing in the three provinces, over the

period 2004-2006 (Fig 3.9). While the demand for genetically improved common carp

seed by nursery farmers in the three provinces investigated has been increasing it varies

greatly between provinces. The demand for seed from genetically improved carp strains

was found to be very high in Thai Nguyen (>80%), and much lower in Vinh Phuc and Yen

100

VinhPhuc

ThaiNguyen

YenBai

2004

2005

2006

Bai (<25%).

Fig 3.7. Proportion of genetically improved common carp fry and fingerlings cultured in Vinh

Phuc, Thai Nguyen and Yen Bai provinces during 2004-2006.

4. Conclusion and Recommendations

There are some very significant conclusions from this study that related directly to the use

of genetically improved common carp in farmers ponds and the management of cultured

fish that are highlighted below.

• Significant differences in growth rate of common carp strains were found

This is the first on-farm growth trial to report difference in growth between strains of

common carp. Specifically the overall findings were the growth rate of the HP3 strain was

superior to the H3B and VNW strains, which in turn were superior to the local strain

(LOC). At the extremes the difference between the worst strains and best strains was 44%.

However, very importantly, the significance of this difference in growth performance was

dependent on the level of feed input into the culture system. In low input systems the

average differences between the best and worst strains was a growth rate of 0.06 grams

per day, where as in high input systems the average difference in growth rate was 0.34

grams per day.

• Very large difference in growth, survival and biomass production were apparent

between farms

The difference in daily growth rate between farms was much greater than between strains.

The best performing farm had from a 31 and 12.6 fold difference in growth rate for the

LOC and HP3 strains respectively. A significant factor explaining these differences can be

attributed to feed input but it is likely that other environmental and husbandry aspects

contribute to these very substantial differences.

• The production of genetically improved common carp by hatcheries and their

demand in different provinces are highly variable

A barrier to the dissemination of genetically improved carp strains is that many hatcheries

breed local (unselected) strains and that demand for genetically improved strains is low in

some provinces. An added complication is that it is difficult, if not impossible, for

hatchery operators and farmers to distinguish between genetically improved and

unselected local strains at the point of purchase.

The following key recommendations emerge from the studies reported in the document

and earlier reports associated with this project.

• Research on the development of genetically improved common carp strains should

be continued as there is clear evidence that these strains are superior under the

conditions of culture compared to local and wild strains.

• Research on the effective dissemination of these strains is required and the

possibility that a form of guarantee or certification can be provided to farmers by

research stations and hatcheries to authenticate that fish being purchased are pure

stocks of genetically improved lines.

• Bioeconomic research is required to determine the cost benefit of using genetically

improved strains and investing in more intensive farming strategies as there may

be little value in farmers with low production systems purchasing genetically

improve carp stocks as the extra expense of buying genetically improved

fingerlings is unlikely to translate into elevated production and income.

• On-farm research and extension activities is required to develop cost effective

strategies to elevate production levels of common carp. These are activities should

be considered of equal importance to the need of producing genetically improved

common carp strains.

• Additional workshops and extension activities with farmers are required to report

the findings of this study and encourage the use of genetically improved common

carp, within the context of the adoption of methods to increase common carp

production.

Acknowledgement

Many people contributed to the success of the on-farm trail to compare growth

performance of common carp strains conduced in farmers’ ponds and rice fields in Thai

Nguyen and Yen Bai province as part of CARD project 002/04VIE. The project was given

significant support from the Provincial Fisheries Centers of Thai Nguyen and Yen Bai.

The efforts and assistance of the 40 common carp farmers who participated in these trials

is gratefully acknowledged.

Appendices

Farm name

Province

Culture

Feed

Strain and No of fish stocked

Area (m2)

input

HP3 H3B VNW LOC

Total

system

Luat

Thai Nguyen

Pond

1000

100

300

2 Ha

Thai Nguyen

Pond

1500

113

452

4 Ke

Thai Nguyen

Pond

550

180

5 Vinh

Thai Nguyen

Pond

800

240

Trong

Thai Nguyen

Pond

1000

100

300

Tuan

Thai Nguyen

Pond

1000

100

300

Truong

Thai Nguyen

Pond

500

150

Lieu

Thai Nguyen

Pond

1000

145

100

300

10 Dieu

Thai Nguyen

Pond

600

100

200

11 Que

Thai Nguyen

Pond

1000

100

150

300

15 Canh

Thai Nguyen

Pond

400

120

16 Lich

Thai Nguyen

Pond

500

150

17 Trung

Thai Nguyen

Pond

400

120

18 Tap

Thai Nguyen

Pond

800

120

240

19 Hung

Thai Nguyen

Pond

300

100

22 Lien

Yen Bai

113

Rice field

1500

113

452

23 Ninh

Yen Bai

680

Rice field

270

24 Hom

Yen Bai

800

Rice field

240

25 Hoan

Yen Bai

100

Rice field

1000

300

27 Hien

Yen Bai

Pond

500

150

32 Nhan

Yen Bai

Pond

1500

113

452

33 Ly

Yen Bai

Pond

800

120

240

35 Thuan

Yen Bai

Pond

1000

100

300

36 Chung

Yen Bai

Pond

1000

100

300

37 Thong

Yen Bai

Pond

1000

100

300

Total

796

496

976

21130

1346

3614

Appendix 1. Name of farm, pond, strain and number of fish stocked

LF: Low feed input system; LH: High feed input system.

Reference

Austin, C. M., A. Pham, T., B. T. Thai and Q. H. Le. 2007a. Fish breeding practices and stock improvement strategies in Vietnam in relation to common carp. 112. MOFI. 2007. Ministry of Fisheries (http://www.fistenet.gov.vn/details.asp?Object=18163919&news_ID=18170767), Thai, B. T., C. P. Burridge and C. M. Austin. 2007. Genetic diversity of common carp

(Cyprinus carpio L.) in Vietnam using four microsatellite loci. Aquaculture 269: 174-186.

Thai, B. T., A. T. Pham and C. M. Austin. 2006. Genetic diversity of common carp in Vietnam using direct sequencing and SSCP analysis of the mitochondrial DNA control region. Aquaculture 258: 228-240.

Thai, T. B. and G. T. Ngo. 2004. Use of pineapple juice for elumination of egg stickiness of common carp (Cyprinus carpio L.). Asian Fisheries Science 17: 159-162. Thien, M. T. and C. N. Thang. 1992. Selection of common carp (Cyprinus carpio, L) in

Vietnam. Selection of research works (1988 - 1992). Agriculture Publisher House, Hanoi (In Vietnamese). Tran, D. T. 1983. A contribution to morphological mutation of common carp (Cyprinus

carpio L.) in Vietnam, A contribution to morphological mutation of common carp (Cyprinus carpio L.) in Vietnam. Pedagogical University (in Vietnam), Hanoi.