LITOPENAEUS VANNAMEI) BIOFLOC SYSTEM IN TAMIL NADU, …xajzkjdx.cn/gallery/411-april2020.pdf ·...

MITIGATE THE SELF POLLUTION OF HIGH DENSITY SHRIMP POND

(LITOPENAEUS VANNAMEI) BIOFLOC SYSTEM IN TAMIL NADU, INDIA

R. LAKSHMANAN, V.MANOHARAN, S.PUVANESWARI AND M.MUTHULINGAM

DHARMAPURAM GANAMBIGAI GOVT ARTS COLLEGE FOR WOMEN

DEPT. OF ZOOLOGY, BHARATHIDASAN UNIVERSITY, MAYILADITHURAI

Abstract:

In these studies the locally available carbohydrate sources such molasses and rice

flour was added as carbon sources to induce the effective and useful for the biofloculation

process in the culture system of pacific white shrimp, Litopenaeus vannamei. The

intensive culture system of biofloc techniques for a period of 135 days. PL13 were

stocked at the rate of 50/m2 in each pond and fed with a standard shrimp feed. Zero water

exchange was done in this method both experiment and control culture ponds.

Throughout period we cheek water quality parameters in the source, experiment and

control ponds. It can observe water quality parameters like temperature, pH, S‰, DO,

NO2, NO3, NH3 and physiological variables like survival, growth; FCR and ABW of

shrimp were recorded during the period. Concentration of temperature, pH, and Salinity

there was no significant. Rest of DO, NO2, NO3, NH3 survival, growth, FCR and ABW

there was significant. BFT ponds were prudent water quality parameters contrast to

control ponds and source water.

Keywords: Post larvae, Food conversion ratio, Average body weight, Dissolved oxygen,

Biofloc treatment

Journal of Xi'an University of Architecture & Technology

Volume XII, Issue IV, 2020

ISSN No : 1006-7930

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Introduction

Biofloc or Periphyton technology, a very recent aquaculture technology for stable

and sustainable production in ponds with zero water exchange. The biofloc defined as

macroaggregates- diatoms, macroalgae, fecal pellets, exoskeleton, remains of dead

organisms, bacteria and invertebrates (Decamp,o.,et al 2002). It possible that microbial

than feed protein (Yoram, 2005). Production of shrimp in limited or zero water exchange

systems can provide more insecurity while addressing both issues (Thakur and Lin 2003).

Feed primary source of macronutrients for shrimp and a major source of pollution in

pond effluent (Tacon and Forster 2003). Protein in feed has also been associated with the

nitrogen load in the effluent from aquaculture activities (Cho et al. 1994). A substantial

portion of the feed goes unutilized and, subsequently, ends up adding to the organic load

of the culture system (Thakur and Lin 2003). In addition to the advantages of biofloc

technology discussed above, Crab et al. (2010b) have recently shown that biofloc

technology constitutes a possible alternative measure to fight pathogenic bacteria in

aquaculture. Intensive aquaculture of crustaceans is one of the fastest growing sectors in

aquaculture production (Wang et al., 2008). In addition to the growing demand for

seafood for human conception, the demand for aquatic products used by the industrial

sector for conversion into fish meal and fish oil products also increases (Peron et al.,

2010). FAO (2009) reported that the total amount of fish meal and fish oil used in aqua

feeds estimated to have grown more than threefold between 1992 and 2006, from 0.9

million tons to 3.06 million tones and from 0.23 million tons to 0.78 million tons

respectively. In terms of fish meal, many intensive and semi intensive aquaculture

systems use 2 to 5 times more fish protein to feed the farmed species than is supplied by



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the farmed product (Naylor et al., 2000). Therefore research in recent times has focused

on the development of feed substitution strategies with minimal supply of fish meal and

fish oil, which are then replaced by the alternative and cheaper sources of protein such as

plant proteins. In contrast intensive and semi intensive systems, extensive and traditional

systems already use little or no fishmeal, and farmers often supply nutrient – rich

materials to the water to enhance growth of algae and other indigenous organisms on

which the fish can feed (Naylor et al., 2000). This inspired researchers to develop the

biofloc technology, which also applicable to intensive and semi intensive systems. With

biofloc technology, where nitrogenous waste generated by the cultivated organisms is

converted into bacterial biomass (contains protein), in situ feed production is stimulated

through the addition of an external carbon source (Schneider et al., 2005). Although

bioflocs show an adequate protein, lipid, carbohydrate and ash content for use as an

aquaculture feed (Crab et al., 2010a), another important factor that is essential for the

growth and survival of aquaculture species are vitamins. We measured before vitamin C

concentration of bioflocs ranging from 0 to 54 µg/g dry matter (Crab, 2010).

Materials and Methods

The study was carried out in Shree Sathiya aqua farms located at Thirunagari near

sirkali south east coast of India. Two ponds were selected for the present study and each

pond was of 0.5 ha area. Pond preparation was initially all the ponds was allowed to dry

and crack to increase the capacity of oxidation of hydrogen sulphide and to eliminate the

fish eggs, crab larva and other predators. The pond bottom was scrapped 2 to 4 cm by

using a tractor blade to avoid topsoil. Subsequently the pond bottom was ploughed

horizontally and vertically a depth of 30 cm to remove the obnoxious gases, oxygenate



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the bottom soil, discoloration of the black soil to remove the hydrogen sulphide odor and

to increase the fertility. The soil pH was recorded in the ponds with the help of cone type

pH meter. The average pH was calculated and required amount of lime was applied to

maintain the optimum pH. Water culture the initial water levels in all the ponds were

maintained at 70 cm level. For blooming, the ponds were fertilized with inorganic and

organic fertilizers. The organic fertilizers such as rice bran, groundnut oil cake and yeast

were soaked overnight and applied the extract to all ponds. The same procedure was

continued for three days. After three days the water color turned to light green. Then

water level was raised to 100 cm of the ponds and added urea and super phosphate to

improve the primary production. Fertilization enhanced optimal algal bloom in all the

ponds and the transparency was ranged from 33 to 36 cm. Stoking Healthy (PCR tested)

Litopenaeus vannamei seeds were purchased commercial hatchery (Golden hatchery at

Marakkanam, Tamilnadu). The seeds were stocked at a density of 50/m2. Before stocking

the seeds were acclimatized to the pond environmental conditions. The seed bags were

allowed to float on the water surface in each pond for 30 minutes in order to adjust the

temperature. The bags were opened and the pond water was introduced slowly by

sprinkling in to the bags for 60 minutes to equalize with pond water quality.

Subsequently, the bags were dragged to different parts of the pond and seeds were

released slowly. After stocking the survival rate was estimated using survival pens

(Happa nets) laid near the outlet of each pond with 100 animals from each pond. Based

on the survival rate on the 3rd day, the feed ratio was decided. Application Pond I was

experiment pond (biofloc), Pond II kept as control. Pond I was applied every fifteen days

interval, 25 Kg of rice flour and 25 kg of molasses were mixed in the pond water (Table:



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1). Feeding shrimp were fed with Avanthi Feed India pvt Ltd, Nellore AP. The feeding

schedule was based on the feed chart given by the company. Blind feeding was done for

first 25 days. Latter the feeding was adjusted based on the check tray observation and

sampling. Four check trays were installed in each pond for monitoring the animal health

and feed intake. The feed ration was divided into 4 times a day as 25%, 20%, 30%, and

25% in the morning (6.00AM), noon (10.00AM), evening (2.00PM), and night (6.00PM)

respectively. The feed was broadcasted from the rope method by using floats. Water

exchange was not recommended in the biofloc system. Sampling was done in the pond

fortnightly during early hours of the day with a cast net. Five hauls were made in each

pond. The shrimps were caught per haul and their individual weights are recorded.

Healthiness, Survival rate, Average body weight (ABW) and Average daily Growth

(ADG) of the animals was estimated. The diameter of the cast net used for sampling was

30 meters. The area of the net was calculated with 70% efficiency of coverage at the

bottom. Growth was monitored after 15th days of every week. The shrimps were caught in

live condition and their individual weights are recorded. The healthiness, survival rate

and average body weight (ABW) were estimated subsequently. The water quality

parameters of the experiment and control ponds were regularly monitored. The water

salinity of the pond was measured by using a hand refrectometer manufactured by Erma-

Japan. The pH of the pond water was recorded by using electronic pH pen manufactured

by Henna Instrumental Company, Japan. The dissolved oxygen was measured by DO

meter. Transparency was observed in terms of light penetration using a secchi disc. The

temperature was measured by using a standard centigrade thermometer. Water samples of

the pond were collected in well cleaned bottles for analysis of nutrients. The estimations



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were usually made within 24 hours of collection. The nutrients such as nitrite, nitrate and

ammonia were estimated following the standard methods described by Strickland sand

parsons (1972).

Results and Discussion

` The physico-chemical parameters of water play crucial role in the culture systems.

Management of water quality parameters in shrimp culture ponds has been essential for optimum

growth and viability of shrimp. Variation in the water quality parameters beyond a particular

range will definitely have its impact on production.

Temperature is one of the most important factors which influence the physiological responses in

the organisms like respiration, metabolism, growth and reproduction. It has pervasive controlling

effect on penaeid shrimp growth. The cultured shrimp grows best in a temperature ranges from

25-33º C. During the study, temperature was recorded between 27.0 to 32.5º C. litopenaeus

vannamei is a euryhaline species it can tolerate the wide range of salinity. The average water

salinity for source experimental and control ponds in the range of 29 to 40 ppt there was no

significant difference between estuarine-water, experimental and control pond. The pH values in

the estuarine-water ranged from 6.2 to 8.9, control pond ranged from 6.1 to 8.3 in the

experimental pond ranged between 6.2 and 8.3 fluctuations was higher in the estuarine-water and

control pond when compared to the experimental pond significant differences was noticed. The

dissolved oxygen concentration varied from 4.5 to 7.9 mg/l in the estuarine-water 3.6 to 5.2 mg/l

in the control pond and 4.1 to 6.8 in the experimental pond. Nitrite represents the intermediary

form by the conversion of ammonia to nitrate. Generally, the high concentration of nitrite is

uncommon in aquatic systems. High nitrite concentrations commonly deactivate hemoglobin in



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the blood crustaceans. However, blood of shrimp does not contain hemoglobin. Therefore,

instead of hemocynin, the oxygen binds to copper at the gills of the shrimp and delivered

throughout the body and cause effect on the circulatory and immune system of aquatic organism.

In the present study, the nitrite-nitrogen levels were recorded from 0.63 to 0.2 mg/l in the

estuarine-water, 0.073 to 0.29 mg/l in the control ponds and 0.093 to 0.19 mg/l in the

experimental pond. For the culture of litopenaeus vannamei, the optimal levels of nitrite

concentration are < 1.0 mg/l. Nitrate is an inorganic nitrogen compound formed at end of the

nitrification process. The concentration of nitrate is usually higher when compared to ammonia

and nitrite. High levels of nitrate will give effect to the osmoregulation and oxygen transport of

the culture of aquatic species. Several researchers have examined ammonia toxicity in various

species of penaeid shrimp and at different developmental stages, especially for juveniles. Chen

and Lei (1990) determined that for P. monodon juvenile, toxicity of ammonia decreased with

exposure time. Chen and Lin (1992) observed an increased susceptibility to ammonia as salinity

decreased from 30 to 10 g L _1 in F. chinensisjuveniles. For P. semisulcatus (De Haan) juveniles

exposed to different concentrations of ammonia-N in a series of acute toxicity tests at four

different water temperatures, Growth rates of M. japonicus juveniles exposed to different

ammonia concentrations were investigated by Chen and Kou (1992). The authors concluded that

ammonia had a stronger effect on weight rather than length. Studies in litopenaeus vannamei

juveniles have been conducted to evaluate acute toxicity levels of ammonia Frias- Espericueta et

al., (1999) and at different salinity levels (15–35 g L _1) Lin & Chen (2001). Racottaand

Herna´ndez-Herrera (2000) evaluated the metabolic responses of ammonia exposure in L.

vannamei. Increase in pH levels favor the formation of the more toxic un-ionized form of

ammonia or enhance the toxic effects Colt & Armstrong (1981). The present study biofloc



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application pond gets more growth and survival because; there is no significant variations in

experiential ponds compare the source and control pond. A Shrimps consume oxygen and

excrete ammonia and carbon dioxide, ammonia is a major excretion product of the fish reared

under intensive feeding regime of high nitrogen containing feeds Kaushik S J., (1980).

Increasing both pH Colt J, et al., (2009) and temperature will increase the percentage of NH3;

Un-ionized ammonia is the toxic form. It is 300 to 400 times more toxic than NH4 + Thurston

RV, et al., (1981). Ammonia is toxic to fish and other aquatic organisms in very low

concentration, about 0.2 mg/L Randall D J, et al., (2002). Ammonia at relatively low

concentration can have negative effects on fish tissues such as gill damage and physiological

factors such as poor growth, higher oxygen consumption and more susceptible to bacterial

infections Piper R G, et al., (1984) and can restrict yields in intensive fish culture Armstrong D,

et al., (1981). When ammonia accumulates to toxic levels, fish cannot extract energy from feed

efficiently. If the ammonia concentration gets high enough, the fish will become lethargic and

eventually fall into a coma and die Hargreaves A J, et al., (2004). In the present study the total

ammonia has ranged in 0.31 to 0.68 mg/lit in the experimental ponds, control ponds were ranged

between 0.38 and 0.93 mg/lit and estuarine-water were ranged between 0.78 and 0.18 mg/lit

(Table 2, 3 & 4). The nitrite, nitrate and ammonia level was significant difference was noticed in

the experimental and control ponds. The present study biofloc application pond gets more growth

and survival because there was a significant variation in experiential ponds and control pond.

When ammonia accumulates to toxic levels, fish cannot extract energy from feed efficiently. The

present study was undertaken to ascertain the using carbon sources (biofloc) on the growth and

survival of the most important to the cultivable shrimps.



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REFERENCES

1. Chen, J.C. and Kou, Y.Z., 1992. Effects of ammonia on growth and molting of

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2. Chen, J.C. and Lei, S.C., 1990. Toxicity of ammonia and nitrite to Penueus monodon

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26. Yoram Avnimelech., 2012. Biofloc Technology - A Practical Guide Book, 2nd Ed.

The World Aquaculture Society, Baton Rouge, Louisiana, EUA. 272p.



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AMOUNT OF CARBON SOURCE UTILIZED: (Table: 1)

DOC EXPERIMENT POND

RICE FLOUR (kg/lit) MOLASSES

(kg/lit)

CONTROL

POND

(kg/lit)

0 25 25 0

15 25 25 0

30 25 25 0

45 25 25 0

60 25 25 0

75 25 25 0

90 25 25 0

105 25 25 0

120 25 25 0

135 25 25 0

EXPERIMENT PONDS: (BIOFLOC) (Table: 2)

DOC Temperature

ºc

Salinity

‰

pH DO

(mg/l)

NO2(ppm) NO3(ppm) NH3 (ppm)

15 27±0.2 28±0.2 6.9±0.2 4.2±1.08 0.045±0.02 0.031±0.02 0.015±0.02

30 25±0.2 33±0.1 6.9±0.1 4.1±1.04 0.029±0.01 0.035±0.01 0.055±0.03

45 27±0.3 34±0.3 7.2±0.3 4.8±1.02 0.012±0.02 0.030±0.02 0.049±0.01

60 28±0.1 32±0.2 7.5±0.2 5.0±1.03 0.013±0.03 0.040±0.03 0.065±0.02

75 28±0.2 35±0.1 7.6±0.4 4.8±1.01 0.042±0.05 0.061±0.05 0.069±0.05

90 28±0.1 40±0.3 7.4±0.2 5.2±1.04 0.028±0.04 0.081±0.04 0.079±0.02

105 30±0.2 38±0.2 7.9±0.3 5.4±1.02 0.069±0.01 0.098±0.01 0.221±0.04

120 29±0.2 40±0.1 8.0±0.1 5.5±1.09 0.061±0.05 0.082±0.05 0.202±0.02

135 30±0.2 42±.02 8.4±0.2 5.3±1.07 0.063±0.04 0.086±0.04 0.264±0.02



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CONTROL PONDS (Table: 3)

DOC Temperature

ºc

Salinity

‰

pH DO

(mg/l)

NO2(ppm) NO3(ppm) NH3 (ppm)

15 27±0.2 28±0.2 6.8±0.2 4.2±1.03 0.015±0.02 0.030±0.02 0.015±0.02

30 25±0.3 33±0.3 7.0±0.1 4.1±1.02 0.019±0.01 0.036±0.01 0.019±0.03

45 27±0.2 34±0.2 7.1±0.3 3.9±1.03 0.022±0.02 0.041±0.02 0.044±0.01

60 28±0.1 32±0.2 7.2±0.2 4.5±1.02 0.042±0.03 0.072±0.03 0.090±0.02

75 28±0.3 35±0.3 7.8±0.5 4.5±1.05 0.084±0.05 0.098±0.05 0.191±0.05

90 28±0.1 40±0.2 7.6±0.6 4.0±1.02 0.082±0.04 0.0110±0.04 0.190±0.02

105 30±0.2 38±0.1 7.9±0.2 4.3±1.05 0.0116±0.01 0.0142±0.01 0.294±0.04

120 29±0.2 40±0.2 8.1±0.3 4.2±1.04 0.0113±0.05 0.0135±0.05 0.291±0.02

135 30±0.1 38±0.3 8.9±0.2 3.9±1.09 0.0115±0.04 0.0140±0.04 0.301±0.02

ESTUARINE-WATER: (Table: 4)

DOC Temperature ºc Salinity

‰

pH DO (mg/l) NO2(ppm) NO3(ppm) NH3 (ppm)

15 27±0.2 28±0.2 6.7±0.2 5.2±1.03 0.019±0.02 0.020±0.02 0.005±0.02

30 25±0.3 32±0.3 7.2±0.1 5.1±1.02 0.023±0.01 0.026±0.01 0.009±0.03

45 27±0.2 32±0.2 7.1±0.3 5.9±1.03 0.020±0.02 0.021±0.02 0.024±0.01

60 28±0.1 32±0.2 7.2±0.2 5.5±1.02 0.032±0.03 0.042±0.03 0.050±0.02

75 28±0.3 34±0.3 7.7±0.5 5.5±1.05 0.064±0.05 0.058±0.05 0.111±0.05

90 28±0.1 36±0.2 7.9±0.6 6.0±1.02 0.072±0.04 0.060±0.04 0.130±0.02

105 30±0.2 36±0.1 8.4±0.2 5.3±1.05 0.096±0.01 0.062±0.01 0.144±0.04

120 29±0.2 38±0.2 8.2±0.3 4.2±1.04 0.083±0.05 0.085±0.05 0.211±0.02

135 30±0.1 38±0.3 8.9±0.2 5.9±1.09 0.0113±0.04 0.0120±0.04 0.271±0.02



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Fig.1. Level of Salinity in the Experimental, Control ponds and Estuarine-water.

Fig.3. Level of pH in the Experimental, Control ponds and Estuarine-water.

0

5

10

15

20

25

30

Biofloc in pond

control pond

source of river

Salinity

Days of culture

s%

0

2

4

6

8

10

Biofloc in pond

control pond

source of river

Days of culture

pH

pH



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Fig 4. Level of Nitrite in the Experimental, Control ponds and Estuarine-water.

Fig 5. Level of Nitrate in the Experimental, Control ponds and Estuarine-water.

0

0.002

0.004

0.006

0.008

0.01

0.012

0.014

0.016

Biofloc in

pond(NO2)

Control pond

(NO2)

Source of river

(NO2)

Days of culture

NO

2NITRITE

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

Source of river

(NO3)

Control pond

(NO3)

Biofloc in

pond(NO3)

DAYS OF CULTURE

NO

3

NITRATE



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Fig 6. Level of Ammonia in the Experimental, Control ponds and Estuarine-water.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

Source of river

(NH3)

Control pond (NH3)

Biofloc in

pond(NH3)

Days of culture

NH

3AMMONIA



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