(Maninhot esculenta (Zea mays matrinxã (Brycon amazonicus) cage

Manioc (Maninhot esculenta) and corn
(Zea mays), alternatives feeds for
matrinxã (Brycon amazonicus) cage
rearing in Amazon floodplain lakes
Heitor Martins-Jr; Rodrigo Roubach; Levy C. Gomes;
Edsandra C. Chagas & José Nestor P. Lourenço
European Aquaculture Society & World Aquaculture Society – Aqua 2006
9 - 13 May 2006, Florence, Italy
Introduction
Cage culture in floodplain lakes as a public demand
towards alternatives to augment local fisheries;
Need for fish feed alternatives, at smaller costs, so that
traditional communities can practice cage fish farming, using
lakes and rivers resources;
Manioc (Manihot sculenta) possess large agricultural
production (637.547 ton./year) and corn (Zea mays) has
smaller production (14.700 ton./year) in Amazonas (SEPROR,
2003). Besides fish, it’s the alimentary base for riverine
communities in Amazon.
Objective
To evaluate the substitution of 25 and 50% of a
commercial feed (28% crude protein) with
manioc and corn in feeding matrinxã reared in
cages in an Amazon floodplain lake.
10cm
Materials and Methods
Juvenile matrinxã (100.1g ± 28.2 g; 19.3cm ± 1.6cm) were
raised in nine cages (6 m3) at a density of 25 fish/m3,
during a period of 90 days in Ariauzinho lake;
Fed at a rate of 5% of their biomass for 6 days/week;
Feed protocols tested:
TC
commercial diet (28%CP)
corn
manioc
100%
0%
0%
TE-25% TE-50%
75%
12.5%
12.5%
50%
25%
25%
Materials and Methods
Temperature and dissolved oxygen were monitored three
times a week;
Water pH, hardness and alkalinity measured every two
weeks;
Monthly, 15% of fish were captured from each cage, to
evaluate the growth in weight and length;
At the end of the experiment we evaluated: survival,
production, weight gain, feed conversion rate, specific
growth rate and condition factor;
Statistical Analisys »»»» Anova (p=0.05).
Results
Water quality at Lake Ariauzinho.
6
29,5
5
29
4
3
28,5
2
28
1
0
27,5
0
30
Dias de criação
60
90
Temperature (ºC)
DO (mg/L)
In-cage morning dissolved oxygen (DO) and water temperature
during matrinxã (Brycon amazonicus) culture in cages for 3 months
at Lake Ariauzinho, Iranduba, AM, Brazil.
Results
In-cage morning water pH, hardness and alkalinity during
matrinxã (Brycon amazonicus) culture for 3 months at Lake
Ariauzinho, Iranduba, AM, Brazil.
Parameters
means ± SD
pH
Hardness
Alkalinity
6.27 ± 0.26 units
23.77 ± 4.87 mg/L
25.85 ± 4.16 mg/L
Results
Weight (g)
Fish growth in weight (g)
250
TC
TE-25%
TE-50%
200
a b b
a a a
150
a a a
100
a a a
50
0
30
60
90
Days of experiment
* means followed by different letters are significantly different at p < 0.05 by T-test.
Results
Standart length (cm)
Fish growth in standard length (cm)
25
a b b
a a a
a a a
20
TC
a a a
TE-25%
TE-50%
15
0
30
60
90
Days of experiment
* means followed by different letters are significantly different at p < 0.05 by T-test.
Results
Production Parameters
Table 1. Matrinxã (Brycon amazonicus) mean production parameters during a 3
month rearing with alternative feeding in cages at Lake Ariauzinho, Iranduba,
AM, Brazil.
Parameters
TC
TE-25%
TE-50%
Weight gain (g)/fish
142.2 ± 16.5
Weight gain (kg)/m3
3.74 ± 0.01
Feed Conversion Rate/FCR
2.5 ± 0.06
Condition Factor
1.482 ± 0.03
1.489 ± 0.02
1.496 ± 0.04
Specific Growth Rate
0.67 ± 0.07
0.40 ± 0.26
0.45 ± 0.11
Survival (%)
98.9 ± 1.92
98.0 ± 3.46
96.6 ± 4.16
Production (kg/m3)
6.0 ± 0.15 a
5.3 ± 0.17 b
5.1 ± 0.21 b
a
a
a
117.3 ± 1.3
b
2.95 ± 0.03
3.2 ± 0.35
b
b
112.6 ± 2.1
b
2.67 ± 0.02
3.4 ± 0.36
b
b
* means followed by different letters are significantly different at p < 0.05 by T-test.
Results
Economy analysis
The analysis considered the sale price of the commercial feed (0.52 US$/kg), of
the manioc (0.11 US$/kg), and of the corn (0.21 US$/kg) during may 2006, in
Manaus, AM, Brazil.
Tested Treatments
Economical indicators
Amount of feed for 90 days of culture (kg)
Cost of the ration (US$/kg)
Save (%) on TC
Feed cost after 90 days of culture (US$)
Cost of feed/kg of fish yield (US$/kg)
Profit (%) on TC
TC
TE-25%
TE-50%
56
55.5
54.7
0.52
0.42
0.33
0.0
18.2
36.4
28.92
23.23
17.81
1.28
1.25
1.11
0.0
2.54
13.82
Discussion
Low water oxygen levels might have influenced the feed conversion
(2,5 to 3,4) reflecting also in the final fish weight (Jobling, 1994). One of
the main risk factor for cage fish production in Amazonian flood plain
lakes (Gomes et al 2006);
Fish feeding represents one of the main factors in production and your
costs can reach among 50 to 80% of the investments (Pereira-Filho,
1995a; Melo et al. 2001; Gomes et al 2005), then a 13.8% economy (TE50%) is significant;
Other works with alternative feeds (fruits, wild or cultivated
vegetables), despite their cheaper price, resulted in inferior growth
rates when compared with balanced fish feeds (Reis, 1985; Mori, 1993;
Roubach & Saint-Paul, 1994, Pereira-Filho, 1995b; Araújo-Lima &
Goulding, 1998; Martins-Jr et al. 2004).
Conclusion
Results indicated that a 50% commercial feed
substitution with manioc and corn has positive effect in
production costs;
However fish yield is higher with 100% commercial
feed;
Therefore a 50% substitution of the commercial feed
would be oriented for subsistence fish culture in riverine
communities.
References
ARAÚJO-LIMA, C.; GOULDING, M. Os frutos do matrinxã: ecologia, conservação e cultivo na Amazônia.
Brasília/DF: Sociedade Civil Mamirauá/CNPq, 1998. 186 p.
BATISTA, V. S.; INHAMUNS, A. J.; FREITAS, C. E. C.; FREIRE-BRASIL, D. Characterization of the fishery in
river communities in the Low-Solimões/High-Amazon Region. Fisheries Management and Ecology, London, v.5,
p.419 - 435, 1998.[
GOMES, L. C.; CHAGAS, E. C. MARTINS-JR, H.; ROUBACH, R. ; ; ONO, E. A.; LOURENÇO, N. 2006. Cage
culture of tambaqui (Colossoma macropomum) in a central Amazon floodplain lake. Aquaculture, 253: 374–384.
JOBLING M. Environmental factors and growth: 155-168. In: Jobling, Chapman & Hall (Ed.). Fish Bioenergetics.
London: Fish and Fisheries Series 13, 1994. 309p.
IBAMA. Portaria n°03/05. 1p., 2005
MARTINS-JR, H.; ROUBACH, R. ; GOMES, L. C.; CHAGAS, E. C. ; ONO, E. A.; LOURENÇO, N. P. Mandioca e
milho, na piscicultura de subsistência do tambaqui em tanques-rede, na várzea da Amazônia. Aquimerco , 2004.
MELO, L. A. S.; IZEL, A. C. U.; RODRIGUES, F. M. Criação de matrinxãs (Brycon amazonicum) em viveiros de
argila/barragens no Estado do Amazonas. Embrapa Amazônia Ocidental, Manaus, Documento Técnicos, n.18, 30p.,
2001.
MORI, L. A. Estudo da possibilidade de substituição do fubá de milho por farinha de pupunha (Bactris gasipaes), em
rações de alevinos de matrinxã (Brycon amazonicum). 1993. 110p. Tese (Mestrado) - INPA, Manaus.
PEREIRA-FILHO, M. Nutrição de peixes em cativeiro. In Val, A.L.; Honczaryk, A. (Ed.). Criando peixes na
Amazônia. Manaus: MCT/INPA, 1995a. p.61-74.
PEREIRA-FILHO, M. Alternativas para a alimentação de peixes em cativeiro. In Val, A.L.; Honczaryk, A. (Ed.),
Criando peixes na Amazônia. Manaus: MCT/INPA, 1995b. p.75-82.
RAPP-PY, L.; DEUS, C. Base para desenvolvimento sustentado da RDS Piagaçu.INPA, 45p., 2003
REIS, F. J. S. Avaliação da eficiência nutricional da algaroba (Prosopis juliflora) na produção de alevinos de
matrinxã. 1985. 38p. Monografia, UFRP, Recife.
ROUBACH, R.; SAINT-PAUL, U. Use of fruits and seeds from Amazonian inundated forests in feeding trials with
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p.134-140, 1994.
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SEPROR – Produção por produtos do Estado do Amazonas, 2003
Acknowledgements
Project n. 2147/02
Collaborative No.22.02.0419.00
CNPq 520080/2003-3
Travel grant and research fellowship
recipient - CNPq
Thank you
Rodrigo Roubach
DIDAQ – SEAP/PR
e-mail: [email protected]
Introduction
Amazonas state = the consumption of fish is of the largest of the
world, more than 600g/person/day in some riverine communities
(Batista et al., 1998).
The high effort of capture decrease the natural stocks of
certain species of fish in some places (Ruffino, 2002).
The fishing is prohibited during the reproductive period (October
to February) and in the period of the flood (April to June) the fish
accomplish lateral migrations, reducing the fish readiness and
increasing the sale prices (IBAMA, 2005).
The invigoration of the technology of culture of fish in cage in
floodplain lakes is being recently objective of public politics for the
government of the Amazonas to supply to crescent it disputes for fish.
The riverine communities are formed by families of low income,
that live of the agriculture and of the subsistence fishing (Py-Daniel &
Deus, 2003), without conditions to maintain an activity of high costs.
In distant places to example of the Amazon ones, the offer of
traditional ingredients (fish flour, flour of blood and soy bran) and the
commercial feed sale is restricted (Pereira-Filho, 1995a)
It is then implicit the need to look for alternatives in the feeding
of the fish, at smaller costs, so that traditional communities can
practice the fish farming in cages, taking advantage of the readiness of
resources of lakes and rivers in Amazonian.
The manioc (Manihot sculenta) it is the product of larger
agricultural production (637.547 ton.) and corn (Zea mays) has smaller
production (14.700 ton.) in Amazonas (SEPROR, 2003). Close to the
fish, this is alimentary base of the riverine communities in Amazonian.