MARINE AQUAPONICS: A SUSTAINABLE TECHNOLOGY MEETS

MUCH SUSTAINABLE DIETS

Dott.ssaNozzi Valentina

Tutor: Prof..ssa Oliana CarnevaliCo-Tutor:Dott. Davide Di CrescenzoProf. Juan Asturiano

Sustainability Of Fish Diet

AQUACULTURE IMPACTS

Coast Exploitation

Pollution

Water Consumption

(FISH MEAL PROBLEM)

AIM

Mitigate the negative effects of fish farming, promoting the integration of best available practices in marine aquaculture.

HOW?

2-Alternative diet

1-New technologies

1 - NEW TECHNOLOGIES

AQUAPONICS

Plant Grow Bed Fish Tank

Pump

MARINE AQUAPONIC:

Experimental Models

 

Plant:Salsola soda

1 - NEW TECHNOLOGIES

Fish: Dicentrarchus labrax(European sea bass)

Plant Grow beds(2m2 each)

Fish tanks(500 Leach)

1 - NEW TECHNOLOGIES

Water recircle: 15’/h

Salinity = 20‰

O2= 80%

T= 25°C

1 - NEW TECHNOLOGIES

EXPANDED CLAY

NH3 NO3

Salsola soda

1 - NEW TECHNOLOGIES

Plants growth

No mortality

ph costant

Nitrite and nitrate didn’t get over threshold value

1 - NEW TECHNOLOGIES

2-ALTERNATIVE FISH DIET

-Fish meal-Wheat-Soybean

-Fish meal-Wheat-Pea-mix of vegetable oils (palm: rapeseed: olive= 1:1:2)-aminoacids source (methionine and aminoacids mix

COMMERCIAL DIET (CONTROL) VEGETABLE RICH DIET (TREATED)

MATERIALS AND METHODS25 25

-Initial Body Weight: 13,1 ± 0,5g

-Feed one time per day for 30 days

-Food despensed: 3% bw

-Anesthetic: MS222 (Sigma Aldrich)

2 – ALTERNATIVE FISH DIET

Bra

in

Liv

er

Int

esti

ne

Sto

mac

h

Spl

een

Gal

lbla

dder

Mus

cle

2 – ALTERNATIVE FISH DIET

MOLECULAR ANALYSIS

- Body Weight

- Liver (Hepatosomatic Index)

- Specific Growth Rate (SGR)

- Food Conversion Rate (FCR)

MORPHOMETRIC ANALYSIS

-Insulin-like growth factor 1 (IGFI)

-Insulin-like growth factor 2 (IGFII) 

-Neuropeptide Y (NPY)

REFERENCE GENE: Β ACT

MORPHOMETRIC ANALYSIS RESULTS

0

2

4

6

8

10

12

14

16

18

20Body weight

Bw (g

)

*

0

0,5

1

1,5

2

2,5

3

Hepatosomatic Index

HSI

(%)

2 – ALTERNATIVE FISH DIET

COMMERCIAL DIET

VEGETABLE RICH DIET

SGR (%) 0,86 1,13

FCR (%) 1,58 1,39

0

5

10

15

20

25

30

35IGF I

Rela

tive

IGF

I abu

ndan

ce (a

.u.) *

0

5

10

15

20

25

30

35 IGF II

Rela

tive

IGF

II ab

unda

nce

(a.u

.)

2 – ALTERNATIVE FISH DIET

MOLECULAR ANALYSIS RESULTS

0

5

10

15

20

25

30

35NPY

Rela

tive

NPY

abu

ndan

ce (a

.u.)

DISCUSSION AND CONCLUSION

This study allowed the optimization and realization of a marine aquaponic systems. Marine aquaponics system is a good

technology used to rear fishes in presence of halophytes plants able to maintain the quality of water

Vegetable reach diet, formulated using plants as protein source with optimal balance of aminoacids and lipids, increases growth

performance in Dicentrarchus labrax juveniles

Marine aquaponics plus vegetable reach diets are a good team: they reduce aquaculture impact and face with a big challenge (fish meal).

DISCUSSION AND CONCLUSION

Fishes feed with vegetable diet showed a higher gene expression of IGF1 and a higher expression of NPY that

codifies for an orexigenic factor involved in the increased appetite control

Hepatosomatic index did not point out differences between groups

Morphometric analysis showed higher body weight in fish feed with vegetable rich diet

-An immersed growth bed dedicated to algae rearing

-Expression of additional genes involved in appetite, immune system and in stress response will be analyze to elucidate the incidence of aquaponic system and vegetable rich diet on marine fish welfare.

-New diet with alternative protein source and new specific diet micronutrient rich to aquaponics systems will be test

-Analysis on plants will also conduct

FUTURE STUDIES