trabalho completo - 52ª Reunião Anual da Sociedade Brasileira de

52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Microalga Schizochytrium sp. como fonte de DHA em dietas para tambacu1
Guilherme de Souza Moura2, Sâmela Keila Almeida dos Santos3, Marcelo Mattos Pedreira4, Eduardo Arruda
Teixeira Lanna5, Gustavo Henrique de Frias Castro6, Talita Andrade Ferreira7, André Lima Ferreira8
1
Projeto em parceria UFV/UFVJM/Alltech Inc.
Pós-doutorando do Programa de Pós-Graduação em Produção Animal – UFVJM, Diamantina, Minas Gerais, Brasil, Bolsista CAPES PNPD. email: [email protected]
3
Mestranda em Zootecnia – UFVJM. Bolsista FAPEMIG. e-mail: [email protected]
4
Professor Adjunto – DZO –UFVM. e-mail: [email protected]
5
Professor Adjunto – DZO – UFV. e-mail: [email protected]
6
Professor Adjunto – DZO – UFVM. e-mail: [email protected]
7
Técnica de laboratório de Aquicultura – DZO – UFVM. e-mail: [email protected]
8
Estagiário do laboratório de Aquicultura– DZO – UFVM. e-mail: [email protected]
2
Resumo: Objetivou-se avaliar a inclusão da microalga Schizochytrium sp. como fonte de DHA em dietas para
tambacu. Com peso de 8,72g ± 1,13, 100 tambacus foram distribuídos em um delineamento inteiramente
casualizado, com cinco tratamentos, quatro repetições e cinco peixes por tanque. O ensaio foi conduzido em sistema
de recirculação com tanques de 35L e controle total de temperatura, aeração e biofiltração. Os tambacus foram
alimentados com cinco dietas contendo a mesma composição nutricional, diferindo apenas nos níveis de
Schizochytrium sp. (0, 10, 20, 30 and 40g.kg-1). Aos 56 dias, os tambacus foram sacrificados e as carcaças
liofilizadas, moídas e pesadas. As seguintes análises foram feitas: matéria seca, matéria mineral, extrato etéreo,
proteína bruta, cálcio, fósforo e perfil lipídico. Os dados da composição corporal foram submetidos à análise de
variância e os efeitos dos níveis de Schizochytrium sp. na dieta foram estimados pela análise de variáveis usando o
modelo de regressão linear. Para análise corporal, os níveis de Schizochytrium sp. influenciaram a proteína bruta, a
qual apresentou efeito quadrático em função do tratamento. Houve efeito linear para ômega 3, DHA e relação
ômega 6:3. Os níveis de ômega 3, DHA e a relação ômega 6:3 melhoraram em 240, 816 e 249% comparado à dieta
controle quando 40 g de Schizochytrium sp.kg-1 foi adicionado. Conclui-se que 40g de Schizochytrium sp.Kg-1 de
dieta promove maior deposição de ômega 3 e DHA corporal.
Palavras–chave: ácidos graxos poliinsaturados, nutrição de peixes, ômega 3
Microalgae Schizochytrium sp. as source of DHA in diets for tambacu
Abstract: The microalgae Schizochytrium sp. levels as DHA source in diets for tambacus were evaluated. One
hundred tambacus with weight of 8.72g ± 1.13 were distributed in a completely randomized design, with five
treatments, four replicates and five fish per tank. The trial was conducted in recirculation system with 35L tanks
and total control of temperature, aeration and biofiltration. Tambacus were fed with five diets contained the same
nutritional composition, differing only in the Schizochytrium sp. levels (0, 10, 20, 30 and 40g.kg-1). After 56 days,
the tambacus were slaughtered, being the carcasses freeze-dried, ground and weighted. Dry matter, mineral matter,
ether extract, crude protein, calcium, phosphorus and lipid profile were mensured. The body composition data were
subjected to variance analysis and the effects of the levels of Schizochytrium sp. in the diet were estimated by
analysis of variables using the linear regression model. For body analysis, the Schizochytrium sp. levels influenced
the body crude protein, which presented quadratic effect in function of the treatments. There was linear effect for
omega 3, DHA and omega 6:3 ratio in relation the levels of Schizochytrium sp. in the diet. The levels of omega 3,
DHA and omega 6:3 ratio improvement in 240, 816 and 249% compared to the control diet when 40g of
Schizochytrium sp.kg-1 of diet was added. It was concluded that 40g of Schizochytrium sp.Kg-1 of diet promote
greater deposition of omega3 and DHA body.
Keywords: fatty acids polyunsaturated, fish nutrition, omega 3
Introduction
The intake of polyunsaturated fatty acids from omega-3 family are increasingly scarce in human food, since
many ingredients containing adequate levels of these are being replaced by others source of fatty acids. Freshwater
tropical fish, as tambacu, usually have in their composition high levels of omega 6 and saturated fatty acids due to
food items present in nature and commercial diets. As the lipid profile of the body may be changed according to the
kind of diet, the inclusion of fatty acids omega 3 in foods can be an alternative for improving nutritional quality of
products.
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Página - 1 - de 3
52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
The Schizochytrium sp. is a microalgae with excellent lipid composition and may have up to 77% fatty acid
(Hoestenberghe et al., 2014). Considering this lipid content, half is represented by Docosahexaenoic acid (DHA),
polyunsaturated fatty acid of the omega 3 family with numerous benefits to animal and human health.
Thus, the body composition of tambacu fed with diets containing the microalgae Schizochytrium sp. as
source of DHA was evaluated.
Material and Methods
The trial was conducted at the Laboratory of Aquaculture and Aquatic Ecology of Animal Science
Department, Federal University of Vales do Jequitinhonha e Mucuri, Diamantina - MG.
With average weight of 8.72g ± 1.13, 100 tambacus (Colossoma macropomum x Piaractus mesopotamicus)
juveniles were distributed in a completely randomized design, with five treatments, four replicates and five fish per
tank. The trial was conducted in recirculation system containing 35L tanks, individual and constant aeration,
temperature-controlled, biofiltration and filter ultraviolet (UV). Three times a week, the tanks were cleaned by
siphoning. Once a week the water quality parameters were measured, as follows: temperature, pH, dissolved
oxygen and ammonia.
Fish were fed with five diets contained the same nutritional composition (90% DM, 32% CP, 3100kcal DE,
3.91% CF, 9.7% EE), being the control diet free of Schizochytrium sp. and the other four with inclusion of 10, 20,
30 and 40 g of Schizochytrium sp.kg-1. The tambacus were fed four times a day (8:00, 11:00, 14:00 and 17:00) to
satiety, preventing food leftovers.
After 56 days all tambacus were slaughtered according the principles of humanitarian of slaughter described
in Instruction No. 3/2000. The fish carcasses were freeze-dried, ground and weighted. Part of the samples of fish
and all experimental diets were forwarded to the Chemical Analysis Laboratory (DZO-UFVJM) for chemical
analysis (dry matter, mineral matter, ether extract, crude protein, calcium and phosphorus). The other part was sent
to the Institute of Food Technology (ITAL- Campinas) for lipid profile analysis.
The body composition data were subjected to statistical analysis using the program Statistical Analysis
System 9.0 (SAS, 2008). Subsequently, the effects of the levels of Schizochytrium sp. in the diet were estimated by
analysis of variables using the linear regression model. As for the water quality parameters were calculated means
and standard deviations to characterize the cultivation environment.
Results and Discussion
During the experimental time the recirculation system maintained the water quality within the range
established by Kubitza (2000) for tropical fish. For body analysis (Table 1), the Schizochytrium sp. levels
influenced the body crude protein, which presented quadratic effect (p <0.05) in function of the treatments. The
inclusion of 20g of Schizochytrium sp.kg-1 increased body crude protein of fish at 9.25% compared to the control
treatment. As the dry matter (DM), mineral matter (MM), calcium (Ca), ether extract (EE) and phosphorus (P), no
differences were observed between the levels studied (p> 0.05).
Table 1. Body compositon of tambacus juveniles fed with diets contained Schizochytrium sp.
Levels of Schizochytrium sp. (g.kg-1)
Nutrients*
CV(%)
Control
10
20
30
40
DM (%)
92.62
93.17
91.80
92.63
92.22
0.61
MM (%)
20.18
21.94
19.88
20.08
18.88
4.26
EE (%)
35.07
35.25
33.21
35.14
37.72
3.73
48.99
50.35
53.52
51.89
49.37
2.22
Total Ca (%)
2.96
3.04
2.99
2.72
2.63
7.25
Total P (%)
2.67
2.54
2.82
2.75
2.82
6.48
CP (%)
1
1
Quadratic effect (p<0,05): Y= 43.8593 + 5.61111X – 0,896887X2; R2= 0.84
Linear effect was observed (p<0.05) for omega 3, DHA and omega 6:3 ratio in relation the levels of
Schizochytrium sp. in the diet (Table 2). When 40g of Schizochytrium sp.kg-1 of diet was added, the levels of omega
3, DHA and omega 6:3 ratio improvement in 240, 816 and 249% compared to the control diet. These results are
according with Li et al. (2009) that studied the addition of Schizochytrium sp. in diets for American catfish
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
(Ictalurus punctatus). The authors verified that adding 2% of Schizochytrium sp. in the diet, the level of omega-3
and DHA body increased to 5.01% and 4.10%, respectively.
The omega 6:3 ratio decreased with the inclusion of Schizochytrium sp. in the diet. These results are similar
to those found by Barilli et al. (2014) that observed omega 6: 3 ratio of 3.02% at add linolenic acid for pacu. These
values were close to that found in this trial (4.13%) when added 40g of Schizochytrium sp.kg-1.
According to the results, the different levels of inclusion of Schizochytrium sp. in the diet influenced the
deposition of omega 3, DHA body in tambacu juveniles, thereby improving the omega 6: 3 ratio.
Tabela 2. Fatty acids profile of tambacus fed with diets contained Schizochytrium sp.
Levels of Schizochytrium sp. (g.kg-1)
Fatty acids (%)
CV (%)
Control
10
20
30
40
Saturated
34.12±0.38
35.12±0.32
36.19±0.36
35.52±0.59
36.84±0.43
0.80
Monounsaturated
38.16±0.17
37.92±0.20
40.71±0.35
38.24±0.32
37.32±0.29
1.53
Polyunsaturated
23.87±0.30
23.45±0.50
19.86±0.40
22.91±0.36
22.38±3.59
3.05
Linoleic
21.04±0.30
20.67±0.40
16.19±0.35
18.54±0.29
17.46±0.40
3.09
Araquidonic
1.02±0.02
0.87±0.02
0.65±0.005
0.63±0.01
0.56±0.03
7.84
Linolenic
1.36±0.04
1.34±0.05
0.99±0.04
1.22±0.03
1.36±0.03
4.92
EPA
0.85±0.01
0.10±0.02
0.85±0.01
0.11±0.005
0.13±0.01
8.28
0.38±0.05
0.89±0.04
1.95±0.02
2.42±0.06
3.10±0.15
3.85
1.82±0.04
2.32±0.09
3.02±0.06
3.74±0.09
4.36±0.18
3.77
22.06±0.32
21.14±0.41
16.84±0.35
19.17±0.28
18.02±0.42
3.01
Omega 6:3
12.13±8.00
9.11±4.56
5.58±7.47
5.13±4.12
4.13±1.99
2.10
No identified
3.86±0.07
3.50±0.07
3.25±0.17
3.34±0.11
3.48±0.15
3.16
a
DHA
b
Omega 3
Omega 6
c
a
Linear effect (p<0,05): Y= -0.342 + 0.695X; R2= 0.99
b
Linear effect (p<0.05): Y= 1.101 + 0.65X; R2= 1.00
c
Linear effect (p<0.05): Y= 13.206 – 1.997X; R2= 0.90
Conclusions
It was recommended 40g of Schizochytrium sp.Kg-1 of diet for the greater deposition of omega 3 and DHA
body for tambacu.
Levels up to 40g should be studied for tambacu.
Acknowledgements
We would like to thank the Alltech Inc, CNPq, FAPEMIG and CAPES for financial support.
References
BARILLI, D.J.; SANTAROSA, M.; ZANQUI, A.B.; BOSCOLO, W.R.; FEIDEN, A.; FURUYA, W.M.; GOMES,
S.T.M.; VISENTAINER, J.V.; SOUZA, N.E.; MATSUSHITA, M. 2014. Incorporation of conjugated linoleic
acid (CLA) and α-linolenic acid (LNA) in pacu fillets. Food Science and Technology 34:74-81.
HOESTENBERGHE, S.V.; FRANSMAN, C.; LUYTEN, T.; VERMEULEN, D.; ROELANTS, I.; BUYSENS, S.;
GODDEERIS, B.M. 2014. Schizochytrium as a replacement for fish oil in a fishmeal free diet for jade perch,
Scortum barcoo (McCulloch & Waite). Aquaculture Research 34:1–14.
KUBTIZA, F. 2000. Tilápia: tecnologia e planejamento na produção comercial. 1st ed. Degaspari. São Paulo
LI, M.H.; ROBINSON, E.H.; TUCKER, C.S.; MANNING,B.B.; KHOO, L. 2009. Effects of dried algae
Schizochytrium sp., a rich source of docosahexaenoic acid, on growth, fatty acid composition, and sensory
quality of channel catfish Ictalurus punctatus. Aquaculture 42:232–236.
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