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Juveniles (3.5 ± 0.3 g) of the white shrimp Litopenaeus vannamei were grown during 40 days with no water exchanges, no food addition and four initial densities (25, 50, 75 and 100 g m -3 , corresponding to between 8 and 32 shrimp m -2), to determine growth rates, which could be achieved using the periphyton growing on artificial substrates as the only food source. The experimental culture units were 12 polyethylene 1 m 3 cylindrical tanks with 4.8 m 2 of total submerged surface (bottom and walls), provided with 7.2 m 2 of artificial substrate (Aquamats™). There were no significant differences in the ammonia and nitrite concentrations determined in the four treatments (0.17-0.19 and 0.10-0.11 mg L -1 , respectively), which remained below the respective levels of concern for shrimp cultures. Mean survival was similar, and ranged from close to 91 to 97%, whereas there were significant differences in mean individual weight, which ranged from 11.9-10.6 g shrimp -1 for the two low initial densities (25 y 50 g m -3), to 8.3-7.7 g shrimp -1 for the other treatments. However, because of the high survival and of the higher initial density, the best biomass yield was with 100 g m -3 . The final nitrogen contents of sediment and water were lower than the initial values, and between 36 and 60% of the difference was converted into shrimp biomass. Cultivo de camarón blanco (Litopenaeus vannamei Boone, 1931) sin recambio de agua y sin adición de alimento formulado: un sistema amigable con el ambiente
Culture of Litopenaeus vannamei with no food addition
Lat. Am. J. Aquat. Res., 40(2): 441-447, 2012
DOI: 10.3856/vol40-issue2-fulltext-19
Research Article
Culture of white shrimp (Litopenaeus vannamei Boone, 1931) with zero
water exchange and no food addition: an eco-friendly approach
Juan Manuel Audelo-Naranjo1, Domenico Voltolina2 & Emilio Romero-Beltrán3
1Universidad Autónoma de Sinaloa, Facultad de Ciencias del Mar
Mazatlán, Sinaloa, México
2Centro de Investigaciones Biológicas del Noroeste, Laboratorio de Estudios Ambientales
UAS-CIBNOR, Mazatlán, Sinaloa, México
3Instituto Nacional de Pesca, Centro Regional de Investigación Pesquera
Mazatlán, Sinaloa, México
ABSTRACT. Juveniles (3.5 ± 0.3 g) of the white shrimp Litopenaeus vannamei were grown during 40 days
with no water exchanges, no food addition and four initial densities (25, 50, 75 and 100 g m-3, corresponding
to between 8 and 32 shrimp m-2), to determine growth rates, which could be achieved using the periphyton
growing on artificial substrates as the only food source. The experimental culture units were 12 polyethylene 1
m3 cylindrical tanks with 4.8 m2 of total submerged surface (bottom and walls), provided with 7.2 m2 of
artificial substrate (Aquamats™). There were no significant differences in the ammonia and nitrite
concentrations determined in the four treatments (0.17-0.19 and 0.10-0.11 mg L-1, respectively), which
remained below the respective levels of concern for shrimp cultures. Mean survival was similar, and ranged
from close to 91 to 97%, whereas there were significant differences in mean individual weight, which ranged
from 11.9-10.6 g shrimp-1 for the two low initial densities (25 y 50 g m-3), to 8.3-7.7 g shrimp-1 for the other
treatments. However, because of the high survival and of the higher initial density, the best biomass yield was
with 100 g m-3. The final nitrogen contents of sediment and water were lower than the initial values, and
between 36 and 60% of the difference was converted into shrimp biomass.
Keywords: Litopenaeus vannamei, artificial substrates, nutrient recycling, biofilm, nitrogen budget, water
quality, Mexico.
Cultivo de camarón blanco (Litopenaeus vannamei Boone, 1931) sin recambio de
agua y sin adición de alimento formulado: un sistema amigable con el ambiente
RESUMEN. Durante 40 días se cultivaron juveniles de camarón blanco Litopenaeus vannamei con un peso
individual de 3,5 ± 0,3 g y biomasas iniciales de 25, 50, 75 y 100 g m-3 (equivalente a 8-32 ind m-2), sin
cambios de agua y adición de alimento, para determinar la tasa de crecimiento usando como única fuente de
alimentación el perifiton desarrollado en sustratos artificiales. Se utilizaron estanques cilíndricos de polietileno
de 1 m3 con tres réplicas por tratamiento, con una superficie de 4,8 m2 (paredes y fondo) y 7,1 m2 de sustrato
artificial (Aquamats™). No se encontraron diferencias significativas entre las concentraciones de amonio
(0,17-0,19 mg L-1) y nitrito (0,10-0,11 mg L-1) determinadas en los cuatro tratamientos. La supervivencia fue
similar, variando entre 91 y 97%. La ganancia en peso individual fue significativamente mayor en los
tratamientos con menor biomasa inicial (25 y 50 g m-3), aunque por la mayor densidad inicial, el mejor
rendimiento en biomasa se observó en los cultivos sembrados con 100 g m-3. Los contenidos de nitrógeno
determinados al final del experimento, en el agua y sedimento, fueron inferiores a los valores iniciales, y entre
el 36 y 60% de sus diferencias se recuperaron en biomasa de camarón.
Palabras clave: Litopenaeus vannamei, sustrato artificial, reciclamiento de nutrientes, biopelícula, balance de
nitrógeno, calidad de agua, México.
Corresponding author: Juan Manuel Audelo-Naranjo (
Latin American Journal of Aquatic Research
The high cost and the large amounts of formulated
feed may become an important limiting factor for
intensive shrimp culture. In addition, shrimp
metabolism and leaching of organic substances from
food and feces may cause poor water quality and pond
bottom deterioration (Burford & Williams, 2001;
Avnimelech & Ritvo, 2003), because of the inverse
relationship between food assimilation efficiency and
culture density (Martin et al., 1998; Zaki et al., 2004).
There are several solutions to the water quality
problem: the traditional way is an increase of water
exchange rates. However, this practice increases the
operating costs due to the high water and energy
consumption, and the lower retention time of nutrients
within the culture systems, that would otherwise be
available for biogeochemical recycling by bacteria and
phytoplankton, thereby increasing the availability of
natural food (Jackson et al., 2003; Crispim et al.,
2007). Other solutions involve the removal of
nutrients either outside or within the culture system. In
the first case, nutrients are removed through different
combinations of physical, chemical and biological
processes, such as mechanical filters, settling tanks,
ozonation or U.V. irradiation, and various types and
designs of biological filters (Timmons et al., 2002;
Hussenot, 2003; Gutierrez-Wing & Malone, 2006).
An alternative is the promotion of growth of
natural planktonic or benthic microbial and microalgal
communities (bioflocs and periphyton, respectively)
present in the pond environment, because their
utilization of nutrients through autotrophic and
heterotrophic processes accelerates the removal of
organic and inorganic wastes, thus improving water
quality; in addition their biomass can be used as a
source of food by the cultivated organisms (Azim et
al., 2002; Avnimelech, 2005).
Both techniques have shown to increase fish and
shrimp production in semi-intensive or intensive
experimental or commercial cultures (Browdy et al.,
2001; Keshavanath et al., 2001; Lopes-Thompson et
al., 2002; Van Dam et al., 2002; Avnimelech, 2007).
In particular, several studies have shown that the
bacterial and microalgal biofilm growing on natural or
artificial submerged substrates (periphyton) may be
used successfully as the main or sole food source for
several freshwater or brackish water fish species
(Ramesh et al., 1999; Azim et al., 2002, 2004; Jana et
al., 2004; Keshavanath et al., 2004). However,
available information for shrimp culture is limited to
some studies on intensive cultures, with formulated
feed as the main food source (Bratvold & Browdy,
2001; Otoshi et al., 2001; Domingos & Vinatea, 2008;
Audelo-Naranjo et al., 2011).
The aim of this work was to evaluate the growth
and production of juvenile Pacific white shrimp L.
vannamei, maintained at four initial stocking densities
in experimental cultures with artificial substrates, with
zero water exchange and no food addition.
The experiment lasted 40 days, from July 2 to August
10, 2009, and was performed on the grounds of a
commercial farm close to the Urías Estuary, Mazatlán,
Sinaloa, NW Mexico (23°25’N, 106°22’W), which is
the source of seawater used by the farm for pond
filling and water exchanges.
Juveniles (3.5 ± 0.3 g) of L. vannamei obtained
from this farm were stocked in triplicate tanks, with
four initial stocking densities (25 ± 7.5; 50 ± 2.3; 75 ±
2.8 and 100 ± 2.5 g m-3: T25, T50, T75 and T100,
respectively), equivalent to 8, 16, 24 and 32 ind m-2.
The experimental units were 12 cylindrical heavy-duty
polyethylene tanks (1 m3, bottom surface: 1.1 m2 and
submerged walls: 3.7 m2). One week before the
experiment, each tank received a 10 cm-deep layer of
homogenized, untreated sediments of an intensive
shrimp farm, and was filled with 1 m3 of 300 µm-
filtered estuary water.
Since no formulated feed was supplied, shrimp fed
only on the periphyton growing on the tank walls and
on the 7.1 m2 (both sides) of the artificial substrates
(Aquamats®, Meridian Applied Technology Systems,
Calverton, Maryland, USA), which had been remained
submerged in the pond water to allow periphyton
growth during the previous 30 days and added in a
circular arrangement to each tank one day before the
experiment, at a distance of 10 cm from the tank wall
(Audelo-Naranjo et al., 2010).
Throughout the study period, the experimental
units were maintained with zero water exchange, but
water was added once per week to each tank (on
average 5% of the tank volume) to compensate the
water lost by evaporation. Continuous aeration was
supplied by a 1 HP blower (0.768 kW; Sweetwater
1HP, Aquatic Eco-Systems, Apopka, FL, USA) to
avoid thermal stratification and for renovation of the
water in contact with the submerged surfaces.
Temperature and dissolved oxygen concentrations
were measured twice daily (8:00 and 18:00 h), using
an air-calibrated YSI model 57 oxygen meter (YSI,
Yellow Springs, OH, USA). Salinity and pH were
measured at 14:00 h with an Atago S/Mill-E
refractometer (Atago, Tokyo, Japan) and a Hanna HI
Culture of Litopenaeus vannamei with no food addition
98150 field pH meter (Hanna Instruments,
Woonsocket, RI, USA).
During the first day of the experiment, triplicate
samples of the water used to fill the tanks were filtered
through Whatman GF/C filters to determine the
concentrations of dissolved inorganic (N-NO3-; N-
NO2-; N-NH4+) and organic N (DON) using traditional
colorimetric techniques (Strickland & Parsons, 1972).
The particulate organic N (PON) retained on the filters
was determined using the method described by Holm-
Hansen (1968). The same methods were applied to
obtain information on the dissolved and particulate N
added weekly to each unit with the water used to
replace water losses. Unionized NH3 was calculated as
in Spotte & Adams (1983).
The initial and final organic nitrogen content of the
sediment and of the accompanying micro- and
meiobiota were determined with the Kjeldahl method
(AOAC, 2005), in triplicate un-sieved samples
obtained from the center and sides of each tank,
during the first and during the final day of the
experiment. The same method was used to determine
the initial and final N content of shrimp, and of
triplicate samples of the periphyton, obtained by
scraping with a scalpel a known area of the substrate
(Audelo-Naranjo et al., 2010).
At the beginning and at the end of the experiment,
all organisms were counted and weighed individually.
Survival (S%) was calculated as S% = 100 (Nf Ni-1),
where Nf and Ni are the final and initial numbers of
shrimp. The mean individual initial and final weights
of the specimens of each unit were used to calculate
the mean daily growth rate (GR) as GR = (Wf-Wi) t-1,
where Wf and Wi are the final and initial wet weights
(g), respectively, and t is the duration (days) of the
The nitrogen budget of each experimental unit was
calculated with the equation:
Wi + Bi + Pi + Si = Sf + Bf + Pf + Wf (Hopkins et al.,
where the inputs were: Wi = total N content (dissolved
and particulate) of the water used for tank filling and
weekly additions, initial N contents of the shrimp
biomass (Bi), of periphyton (Pi), and of the sediment
and accompanying micro- and meiobiota (Si).
Outputs: final N content of the sediment (Sf), of
the shrimp biomass harvested (Bf), of the periphyton
(Pf), and of the water discharged at the end of the
experiment (Wf). An additional output were the
shrimps escaped overnight from the experimental
units, which were collected the following morning,
weighed, frozen and analyzed separately.
The mean values of temperature, dissolved oxygen,
pH, salinity and dissolved nutrient concentrations
were compared using repeated measures ANOVA
tests, or the equivalent Friedman’s non-parametric test
when the data were not normal or homoscedastic
(Kolmogorov-Smirnov and Bartlett’s tests). The mean
values of final yields, survival, individual weights, and
growth rate were compared using one-way ANOVA
or Kruskall-Wallis tests, after arcsine square root
transformation in the case of final survival. In all
cases, the level of significance was P = 0.05 (Zar,
There were no significant differences between the
mean water characteristics: morning and afternoon
mean water temperatures and dissolved oxygen
concentrations ranged from 28.5 to 31.5 °C and
between 6.1 and 6.3 mg L-1, respectively. The mean
pH value was 8.4 in all treatments, and salinity varied
between 37.4 and 37.5 g L-1. Ammonia and nitrites
remained between 0.17-0.19 and 0.10-0.11 mg L-1,
respectively, and the mean values of calculated
unionized ammonia were below 0.03 mg L-1; nitrates
varied between 0.26 and 0.29 mg L-1.
The mean DON and PON concentrations
determined in the four treatments were similar, and
ranged from 0.78 to 0.79 and from 1.27 to 1.29 mg
L -1, respectively (Table 1).
Mean final survival varied between 90.7 and
97.3%, without differences between treatments. In the
case of mean final weights and daily growth rates,
there were no statistically significant differences
between the two low biomass treatments (25 g m-3:
11.9 ± 2.6 g and 0.20 ± 0.05 g day-1; 50 g m-3: 10.6 ±
1.2 g and 0.17 ± 0.02 g day-1, respectively). Both were
significantly higher than the high-density treatments
with final weights of 8.3 ± 0.3 and 7.7 ± 0.5 g, and
growth rates of 0.10-0.11 ± 0.01 g day-1.
There were also significant differences in mean
final yields: the lowest and the highest (73.6 ± 4.7 and
199.6 ± 19.9 g experimental unit) were those of the
tanks stocked with 25 and 100 g of initial biomass.
The tanks stocked with 50 and 75 g gave intermediate
values (145.5 ± 3.5 and 139.6 ± 16.6 g), and there was
no difference between these two treatments (Table 2).
Since no food was added, the major nitrogen input
to the experimental units was that contained in the
initial sediment, followed by that of the periphyton
(12.5 and 7.4 g m-3, respectively, composed mainly by
bacteria and algae, as well as ciliates, nematodes,
occasionally with copepods and amphipods, and few
Latin American Journal of Aquatic Research
Table 1. Mean values (± standard deviation) of daily water temperature (T°C) and dissolved oxygen concentrations (DO:
morning and afternoon readings, am and pm, respectively), pH and salinity (afternoon readings), and weekly nutrient
concentrations in the cultures of Litopenaeus vannamei with artificial substrate (Aquamats™) and increasing initial
biomass (25 to 100 g m-3).
Tabla 1. Valores medio (± deviación estándar) de los registros diarios de temperatura (T°C) y oxígeno disuelto, pH,
salinidad y concentración semanal de nutrientes por tratamiento y horario en los cultivos de Litopenaeus vannamei con
sustrato artificial (Aquamats™) e incremento de biomasa inicial (25 a 100 g m-3).
T25 T50 T75 T100
T°C am 28.5 ± 2.6a 28.5 ± 2.6a 28.7 ± 2.6a 28.7 ± 2.6a
T°C pm 31.1 ± 2.3a 31.2 ± 2.4a 31.3 ± 2.4a 31.5 ± 2.4a
DO am (mg L-1) 6.3 ± 1.1a 6.2 ± 1.2a 6.3 ± 1.1a 6.3 ± 1.2a
DO pm (mg L-1) 6.2 ± 1.2a 6.3 ± 1.2a 6.1 ± 1.1a 6.1 ± 1.2a
pH 8.4 ± 0.1a 8.4 ± 0.1a 8.4 ± 0.1a 8.4 ± 0.1a
Salinity (psu) 37.4 ± 1.1a 37.5 ± 1.1a 37.5 ± 1.1a 37.5 ± 1.1a
N-NH4+ (mg L-1) 0.18 ± 0.07a 0.18 ± 0.07a 0.17 ± 0.08a 0.19 ± 0.07a
N-NH3 (mg L-1) 0.02 ± 0.01a 0.02 ± 0.01a 0.02 ± 0.01a 0.03 ± 0.01a
N-NO2- (mg L-1) 0.10 ± 0.07a 0.11 ± 0.07a 0.10 ± 0.08a 0.10 ± 0.09a
N-NO3- (mg L-1) 0.27 ± 0.08a 0.29 ± 0.07a 0.26 ± 0.08a 0.27 ± 0.09a
DON (mg L-1) 0.78 ± 0.10a 0.78 ± 0.10a 0.79 ± 0.08a 0.79 ± 0.09a
PON (mg L-1) 1.28 ± 0.31a 1.27 ± 0.35a 1.27 ± 0.35a 1.29 ± 0.43a
The equal superscripts indicate lack of significant differences (one-way repeated
measures ANOVAs, P = 0.05). (DON: dissolved organic nitrogen, PON: particulate
organic nitrogen).
Table 2. Mean values (± standard deviation) of production variables in the cultures of the white shrimp Litopenaeus
vannamei with artificial substrate (Aquamats™) and increasing initial biomass (25 to 100 g m-3).
Tabla 2. Valores medio (± desviación estándar) de las variables de producción de los cultivos de camarón blanco
Litopenaeus vannamei con sustrato artificial (Aquamats™) e incremento de biomasa inicial (25 a 100 g m-3).
T25 T50 T75 T100
Final survival (%) 91.4 ± 7.8a 96.3 ± 0.2a 90.7 ± 6.4a 97.3 ± 2.3a
Initial weight (g) 3.5 ± 0.3 3.5 ± 0.3 3.5 ± 0.3 3.5 ± 0.3
Final weight (g) 11.9 ± 2.6b 10.6 ± 1.2b 8.3 ± 0.3a 7.7 ± 0.5a
Growth rate (g day-1) 0.20 ± 0.05b 0.17 ± 0.02b 0.11 ± 0.01a 0.10 ± 0.01a
Yield (g) 73.6 ± 4.7a 145.5 ± 3.5b 139.3 ± 16.7b 199.6 ± 19.9c
Different superscripts indicate significant difference between values in the same row (One-way ANOVAs, P = 0.05,
polychaetes). The contribution of initial biomass
(nitrogen content: 3.68 ± 0.09%, wet weight) was
between 0.9 to 3.7 g m-3, depending on the initial
density; the water used to fill the tanks and for weekly
additions added 2.3 g of N to the mean total inputs.
Among outputs, the N contents of sediment (11.8
to 10.5 g m-3), periphyton (3.7 to 3.5 g m-3, both
decreasing with increasing initial shrimp biomass),
and water (1.6 increasing with biomass to 2.0 g m-3)
were lower than the initial values: sediment was the
main N compartment, and the values decreased with
increasing stocking density. The increased N content
of the shrimp biomass (in this case increasing from 2.7
to 7.2 g m-3, depending on stocking density)
represented between 34 and 60% of the difference
between the initial and final values of sediment, water
and periphyton.
The N content of the shrimp escaped from their
tank represented only 0.2 to 0.4 g m-3. Therefore,
between 2 and 3.2 g of N were missing from the
Culture of Litopenaeus vannamei with no food addition
Table 3. Nitrogen budgets in the culture of the white shrimp Litopenaeus vannamei with artificial substrate (Aquamats™)
and increasing initial biomass (25 to 100 g m-3). The values are mean ± standard deviations of the N inputs and outputs
Tabla 3. Balance de nitrógeno en el cultivo de camarón blanco Litopenaeus vannamei con sustrato artificial
(Aquamats™) e incremento de biomasa inicial (25 a 100 g m-3). Valores medio ± deviación estándar de los ingresos y
egresos de N (g).
T25 T50 T75 T100
Sediment 12.5 ± 0.7a 12.4 ± 0.2a 12.5 ± 0.7a 12.5 ± 0.7a
Periphyton 7.4 ± 0.03a 7.4 ± 0.02a 7.4 ± 0.03a 7.4 ± 0.03a
Water 2.3 ± 0.2a 2.3 ± 0.2a 2.3 ± 0.2a 2.3 ± 0.2a
Initial biomass 0.9 ± 0.06a 1.9 ± 0.1b 2.7 ± 0.01c 3.7 ± 0.01d
Total 23.1 ± 0.16a 23.8 ± 0.12b 24.9 ± 0.15c 25.8 ± 0.17d
Sediment 11.8 ± 0.1d 11.2 ± 0.1c 10.8 ± 0.1b 10.5 ± 0.1a
Periphyton 3.7 ± 0.1b 3.4 ± 0.2a,b 3.6 ± 0.4a,b 3.5 ± 0.1a
Water 1.6 ± 0.06a 1.9 ± 0.06b,c 1.8 ± 0.06b 2.0 ± 0.1c
Final biomass 2.7 ± 0.2a 5.2 ± 0.1b 5.0 ± 0.6b 7.2 ± 0.7c
Escaped shrimps 0.2 ± 0.01a 0.2 ± 0.01a 0.4 ± 0.01b 0.2 ± 0.01a
Total 20.1± 0.22a 21.8 ± 0.18b 21.6 ± 0.9b 23.3 ± 0.07c
Missing 3.0 ± 0.2b 2.0 ± 0.2a 3.2 ± 1.0a,b 2.5 ± 0.7a,b
Different superscripts indicate significant difference between values in the same row (One-
way ANOVAs, P = 0.05, a<b<c).
global budget (Table 3). Assuming similar growth and
grazing pressure as on the Aquamats, the biofilm on
the tank walls (3.7 m2), and on aeration lines and air
stones (approximately 0.8-1 m2) could not contain
more than 0.2-0.25 additional g. Therefore, the
remaining N was probably lost to the atmosphere,
either as molecular N produced through denitrification
or more probably, in view of the aeration provided, as
gaseous NH3, which represented on average 11% of
the total ammonia present in the tanks.
The mean temperature, dissolved oxygen, pH and
salinity values were well within the appropriate ranges
for L. vannamei culture (Treece, 2000). Salinity was
higher than the isosmotic point (approximately 20 g
L-1) which may have a negative effect on the energy
budget of the white shrimp (Valdez et al., 2008),
although values as high as 40 g L-1 does not seem to
affect significantly the growth rate of this species
(Ponce-Palafox et al., 1997).
Dissolved and unionized ammonia, as well as
nitrite and nitrate values remained below the
respective safety levels for shrimp culture (7.09, 0.13,
25.7, and 232 mg L-1, respectively) (Frías-Espericueta
et al., 1999; Tsai & Chen, 2002; Lin & Chen, 2003).
This confirms the importance of the microbiota
adhered to the submerged surfaces, which used the
dissolved and particulate nutrients present in the water
column and in the sediments for their growth and
development. Thus, the periphyton served to maintain
water quality and to provide food for the cultured
shrimp, and the low final nitrogen concentrations in
water and sediment prove that its metabolism was
adequate to prevent deterioration of the culture
Additionally, the weight gain of the shrimp
confirms the importance of the biota associated to
artificial substrates as a natural food source for farmed
organisms. This community forms a complex food
web, in which the consumers and detritivores use
autotrophic microorganisms as their food source, and
the dissolved organic and inorganic nitrogen produced
by their metabolism is recycled into new biomass by
the autotrophic microalgae-bacteria mats. In the
trophic structure of the experimental units, shrimp
were the top consumers, and therefore were the final
beneficiaries of the nutrient and energy flow of these
closed systems.
Latin American Journal of Aquatic Research
The best final individual weights (11.9 and 10.6 g),
were obtained with the intermediate initial stocking
densities (25 and 50 g of initial biomass, equivalent to
8 and 16 ind m-2, respectively), and the best biomass
gain was with the highest initial biomass, although the
individual weight gain was not as high as that obtained
with the two lower stocking densities. In all cases, the
regime of closed culture promoted nutrient recycling,
provided sufficient food for the cultured organisms,
eliminated the cost of formulated feed and water
exchanges and was, at the same time, environmentally
friendly because it minimized the environmental
impact of nutrient-loaded effluents.
Culture experiments with mesocosms should not
be used to calculate possible yields of full-scale
cultures or for cost/benefit analysis, but to verify the
feasibility of a different approach for large-scale
cultures. However, on the basis of these results,
shrimp may be grown successfully in closed cultures
using submerged substrates. Once the proper
biological load is established through additional work
at the pilot scale, periphyton may maintain water
quality and serve at the same time as the main or even
as the only source of food, with yields close or higher
than the <1000 kg ha-1 which, according to official
statistics (SAGARPA, 2010), is the mean yield of
most Mexican semi-intensive shrimp farms.
Supported by PROFAPI2011/016 and CIBNOR
project AC0.38. V. Nuñez, O. Zamudio, B. Mejía and
J. Madero of the Academic Group ‘Shrimp and Fish
Culture’ helped with the field and analytical work.
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... Large quantities of formulated feed with high animal protein content can cause eutrophication in aquaculture systems, increasing the nutrient load in effluents (Tacon et al., 2002). Their use increases production costs (Audelo-Naranjo et al., 2012) and can result in an insufficient supply of some essential nutrients (Crab et al., 2007), thus becoming a limiting factor in intensive systems. To minimize or reduce this nutrient deficiency, organic and inorganic fertilizers can be added to the cultivation systems to promote growth of the microbial community, which is a food source (Brito et al., 2009a(Brito et al., , 2009bAsaduzzaman et al., 2010;Lara-Anguiano et al., 2013). ...
... In intensive farming systems with Pacific white shrimp (Litopenaeus vannamei), microalgae (through photosynthesis) and the other constituents of the microbial community can play an important role in recycling nutrients (Audelo-Naranjo et al., 2012;Sánchez et al., 2012) decreasing the anoxic zones in ponds and alleviating the nutrient load in wastewater (Martínez-Porchas et al., 2010), while providing a nutrition source for shrimp in semi-intensive (Otoshi et al., 2011) and intensive systems (Sánchez et al., 2012). ...
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The aim of this study was to evaluate the effect of the addition of Navicula sp. on plankton composition and postlarvae growth of Litopenaeus vannamei reared in culture tanks with zero water exchange systems. Four treatments were considered: zero water exchange (ZWE); ZWE with the addition of feed (ZWE-F); ZWE with the addition of Navicula sp. (ZWE-N) and ZWE with the addition of feed and Navicula sp. (ZWE-FN), all in triplicate. Shrimp of 17.7 ± 0.02 mg were stocked at a density of 2500 shrimp m-3 and microalgae added on the 1st, 5th and 15th day at a density of 5x10(4) cell mL-1. The shrimp were fed a commercial feed composed by 42% crude protein four times a day except in the ZWE treatment. For data analysis we used Cochran, Shapiro-Wilk, ANOVA, Tukey and Student-t tests (P
... Survival showed equal values between alkalinity and concentrations in clear water and biofloc systems. These results (100.00%) were higher than those observed by AUDELO-NARANJO et al. (2012) andFRÓES et al. (2013) which cultivated juvenile L. vannamei in systems without water renewal for 40 days and 3 months (values from 97 to 95%), respectively. ...
Esse estudo objetivou avaliar o efeito da alcalinidade no consumo alimentar e demais parâmetros de desempenho de juvenis de Litopenaeus vannamei cultivados em água contendo bioflocos e água clara. Para tanto, durante 3 dias, camarões de 4,06 ± 0,34 g foram mantidos em recipientes de 3 L, sob as concentrações Controle, 50, 100 e 200 mg L-1 de alcalinidade, com 5 repetições cada, em bioflocos e água clara. O consumo alimentar foi verificado uma vez ao dia e os demais parâmetros de desempenho foram avaliados ao final do experimento. Nesse estudo, verifica-se que o consumo alimentar dos camarões não é afetado entre os níveis de alcalinidade e nos sistemas de água clara e bioflocos. Já o ganho em peso e a taxa de crescimento específico são afetados positivamente nas maiores concentrações de alcalinidade, no sistema de bioflocos, onde demonstram os melhores resultados. E a sobrevivência, assim como o consumo alimentar, não é afetada entre os níveis de alcalinidade e nos sistemas de água clara e bioflocos. Contudo, a possibilidade de exposição à concentrações de alcalinidade inapropriadas, durante longos períodos de tempo, pode afetar negativamente os animais, assim, ressaltando a importância da manutenção da alcalinidade em níveis adequados à espécie cultivada.
... Marine shrimp aquaculture requires new technologies to eliminate and control water exchange, discharge of effluents, disease outbreaks, and overuse of feeds (Lara et al., 2012). In recent years, high-density shrimp farming under limited water exchange has been possible through manipulation of microbial communities in water (Azim and Little, 2008;Samocha et al., 2010;Krummenauer et al., 2011;Audelo-Naranjo et al., 2012). The principle of minimum water exchange crops is based on the addition of carbon sources to balance the C:N ratio in water. ...
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This study was conducted to evaluate the effect of rice byproducts on water quality, microbial community, and growth performance of L. vannamei juveniles. Shrimp of 0.98±0.10 g body weight (BW) were reared in 49 tanks of 1.5 m3 under 127 animals m−2 for 77 days. Rice bran, rice grits, and rice hulls were mixed into five different fertilizers varying their fiber content (90, 110, 150, 200, and 250 g kg−1) and compared against sugarcane molasses (MO) and unfertilized tanks (UNF). Rice byproducts and MO were applied in water three times a week at a fixed rate of 4.5 g m−3. Water salinity, pH, temperature, and dissolved oxygen reached 43±2 g L−1, 8.03±0.32, 30.2±0.90 °C, and 5.03±0.53 mg L−1, respectively. Settleable solids (SS) were higher in tanks fertilized with rice byproducts (from 2.5±1.0 to 3.1±1.1 mL L−1) and MO (3.4±1.0 mL L−1). Total ammonia nitrogen (0.19±0.09 mg L−1), nitrite (5.97±2.04 mg L−1), and nitrate (1.29±0.48 mg L−1) were kept low without any significant differences among treatments. The concentration of heterotrophic bacteria and fungi was significantly higher in rice byproducts compared with MO. Water fertilization had no effect on final shrimp survival (85.5±9.5%), weekly growth (0.72±0.11 g), and feed conversion ratio (1.59±0.10). Tanks treated with rice byproducts, except with 90 g kg−1 fiber, resulted in a higher final shrimp BW (from 9.04±1.56 to 9.52±1.89 g) compared with MO (8.75±2.14 g) and UNF (7.74±1.48 g). Gained yield and feed intake were significantly higher for tanks treated with rice byproducts than with UNF. A mix of rice byproducts can be equally or more effective as carbon sources to shrimp culture than MO.
... A decrease in these values could be related to over-feeding in aquaculture systems and associated to food waste, affecting the profitability of the culture. No reports in the literature showed that the use of biofilm could improve these rates, even knowing that the additional food provided by the biofilm could contribute to the reduction in the quantities of feed and better incorporation of C and N, due to increased recycling nutrients in the cropping system (Abreu et al. 2007;Audelo-Naranjo et al. 2012). By analyzing the results of the present study, in general, the treatments with artificial substrates presented FCEs approximately 10% higher than treatments without the addition of biofilm, indicating that the inclusion of these structures could contribute to better feeding efficiency. ...
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This study evaluated the use of biofilm in a Litopenaeus vannamei biofloc system using different feeding rates. Shrimp juveniles (0.89 ± 0.35 g) were stocked at 300 shrimp m−3 in 24,150-L tanks. The feeding rates were calculated by considering an expected weekly growth of 1 g week−1 and an estimated weekly mortality of 0.5%. Each treatment corresponded to a different feeding rate, and each feeding rate corresponded to a fixed food conversion ratio. Thus, the treatments tested were as follows: T0 and T0+B (without addition of artificial food, with and without biofilm addition, respectively); T0.6 and T0.6+B; T1.2 and T1.2+B; and T1.8 and T1.8+B. The study lasted 42 days. At the end of the study, shrimp that were grown with no artificial food presented lower final weights and minor survival, independent of the addition of biofilm. The T1.2+B treatment did not differ significantly from the T1.2, T1.8, and T1.8+B treatments for the growth and feeding parameters. The survivals were higher than 91% in all of the feed treatments, and no significant differences were detected among these treatments. In contrast, the results allowed the conclusion that the presence of biofilm in the T1.2+B treatment represented a feed saving of 35% of the total amount of artificial food offered. This could represent a significant value in the cost of operation and may make the biofloc technology (BFT) system more cost-effective and environmentally friendly. The use of BFT in conjunction with biofilm can benefit shrimp farming by reducing the amount of feed supplied.
... In the present study, the total absence of artificial feed in the first phase negatively affected the survival of shrimp, indicating that the shrimp did not survive when fed only in the presence of natural productivity provided by bioflocs. Audelo-Naranjo et al. (2012) grew L. vannamei for 42 days at different stocking densities with no food addition and no water exchange, and obtained better results than those observed in the present study. Moreover, Roy et al. (2012) reared shrimp with no artificial food addition, observing survival rates higher than the values observed in the present study (poor survival was 61%). ...
The natural productivity in biofloc culture systems could be an important source of supplementary food to shrimp, representing savings in artificial feed. The aim of the present study was to evaluate the effects of using different feeding rates for a period of 21 days with a posterior re-feeding period in a microcosm system in the presence of bioflocs. Litopenaeus vannamei juveniles (1.14 ± 0.38 g) were stocked at 400 shrimp m⁻³ in 150-L tanks in a biofloc recirculation system in two phases. The feeding rates were calculated considering an expected weekly growth of 1 g week⁻¹ and an estimated weekly mortality of 0.5%; each treatment corresponded to a different feeding rate, and each feeding rate corresponded to a fixed food conversion ratio. The first phase (food restriction) lasted 21 days, and the following treatments were used: T0 (no artificial feed addition), T0.3, T0.6, T0.9, T1.2, T1.5, T1.8 and T2.1. In the second phase (re-feeding), the feeding rate was calculated based on the average of the best results in the first phase of the experiment (FCR = 1.45). The re-feeding period lasted for more 29 days. There were no observed significant differences in the water quality parameters among the treatments (P > 0.05). At the end of the food restriction, the shrimp in T0, T0.3 and T0.6 presented lower final weights (P < 0.05), and the weights in the other treatments did not significantly differ (P > 0.05). The survival rate was lower only in T0 in the two phases of the study. The other treatments presented survival rates higher than 95%, with no significant differences among them. The feed intake did not increase during the re-feeding period, indicating that hyperphagia did not occur after a period of food restriction. The SGRs were higher for treatments that received lower amounts of feed in the first phase, and treatments T0, T0.3 and T0.6 presented partial weight compensation compared with the treatments with higher feeding rates. This study indicates that shrimp can be reared in a biofloc system with lower feeding rates, obtaining partial weight compensation and high survival rates and saving up to 24.79% of the artificial feed.
... However for power, has fully gained adoption suited to local realities and operational in Nigeria. The zero-exchange technology has revolutionized mariculture and presently drives (saline) aquaculture industry in Europe and Australia (Allan et al 2008), America and globally (Audelo-Naranjo et al 2012) with outstanding results. The zero-exchange technology is suitable for mangrove-aquaculture if applied within the limits of E.S.H.I.A. at low-scale and community-driven level. ...
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The coastal waters of Nigeria are lined with mangroves which provide invaluable ecological services. Much of these mangroves are not adequately classified or protected by specific laws, policies or agencies. There are different perceptions on the sustainability of aquaculture in mangroves. This paper upholds the principle of precautionary approach where doubts arise and suggests global best practices including elaborate technical assessments in site selection for pond construction, policy frameworks that ensure mangroves maintain their functions while being exploited, requiring investors to maintain environmental management systems, product certification, allocation of aquaculture sites outside pristine mangrove areas, empowerment of relevant agencies for continual satellite-based environmental change monitoring and making reforestation obligatory to investors. It also outlines mangrove management strategies and policies in selected Asian countries compared to Nigeria, harmonizing priorities of externally-funded mangrove projects with local priorities and needs and other supportive policy instruments for strengthening independent regulatory agencies for biodiversity conservation of mangroves in Nigeria. The paper particularly advocates mangrove-friendly aquaculture models such as silvofishery vis-a-vis community concessions and adoption of integrated coastal zone management.
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The aim of this study was to evaluate variability of nitrifying bacterial community in the biofilm and in the water of a recirculating aquaculture systems (RAS) in a tilapia farming in order to determine if nitrification process is dependent, or not, of nitrifying bacteria abundance. Biofilm and water samples were collected periodically for 30 days and analysed with the fluorescent in situ hybridization (FISH) technique, used to quantify ammonia‐oxidizing bacteria (AOB) and nitrite‐oxidizing bacteria (NOB). Ammonia presented the peak in the first week, while the nitrite's maximum was recorded in the second week. Nitrate increased steadily, indicating nitrification activity. Total bacterial abundance in biofilm increased continuously, while in water, it did not change significantly. In the biofilm, number of AOB was high at beginning, decreased after few days and increased again following augment of ammonia. Number of NOB also showed an increase in abundance in biofilm following the increment of nitrite and nitrate. In water, AOB and NOB did not show major variability. Relative abundance of nitrifying bacteria represented more than 30% of total bacteria in biofilm at beginning of the experiment. Their contribution decreased to >3% in last days. It indicates that nitrifying bacteria are biofilm colonizers, and that their activity seems to be directly related to the concentration of nitrogen compounds. However, contribution of nitrifying bacteria did not vary much along the time. We may conclude that the biofilm‐nitrifying bacteria plays major role in nitrification process in RAS and that the activity of these organisms is dependent of their abundance in response to the concentration of nitrogen compounds.
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Se evaluó el efecto de BlueEnergyRent producto a base de levadura Saccharomyces cerevisiae y melaza, en el cultivo de Camarón blanco Litopenaeus vannamei, determinando el impacto en los parámetros de calidad del agua, y productivos. El experimento se llevó a cabo en la granja acuícola Acuilan, ubicada en La Antigua, Veracruz, México, en el año 2015. En el cultivo de camarón se agregó 1.5 g m-3 día-1 de la mezcla activa melaza-levadura como primer tratamiento y una dosis diaria ajustada en base al nitrógeno amoniacal total en el segundo tratamiento. Ambos fueron comparados contra un tratamiento con flujo constante de agua. Se observó que BlueEnergyRent no afectó negativamente la calidad del agua, los parámetros productivos presentaron mejores niveles con el tratamiento en base al nitrógeno amoniacal total, y se logró reducir el consumo de agua por cada kg de camarón producido a 3.9 m3 kg-1. Se cosecharon organismos sanos con crecimiento normal con una tasa de conversión alimenticia de 1.19. Al usar BlueEnergyRent se mejora el uso del agua sin afectar el desempeño del cultivo.
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The release of wastewater and the shrimp feed cost are the main challenges faced by the shrimp farming industry. An alternative solution to both problems is biofloc production in a unit external to the farm, in an activated sludge system for effluent treatment. The treatment system’s influent was composed of the shrimp farm wastewater supplemented with urea and sugarcane molasses. The results show that the average removal of chemical oxygen demand was 71% and the average biofloc production in the reactor was approximately 1.5g.L-1. Adding molasses to the influent contributed to the increase in the quantity and diversity of existing microorganisms that are beneficial to cultured shrimp. The mass balance of nitrogen compounds confirmed that nitrification occurred in the system. Therefore, the use of the activated sludge system is a viable and environmentally suitable alternative to produce bioflocs and shrimp farming effluent treatment.
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The growth and survival of Penaeus vannamei postlarvae was measured at temperatures of 20, 25, 30 and 35 °C and salinities of 20, 30, 35, 40 and 50%.. Groups of 30 animals were used in each combination of conditions, in triplicate. The results clearly show that juveniles of this species have their best survival between temperatures of 20 and 30 °C and salinities above 20%.. Best growth was obtained between temperatures of 25 and 35 °C, with little difference being noted among salinities. Survival and growth coincide best at around 28 to 30 °C and 33 to 40%.. Calculated overall production was shown to be best in these conditions. The results demonstrate a high coincidence between the experimentally determined optimum conditions for production and the prevailing conditions in the coastal environment from which the animals originated.
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Marine shrimp Penaeus semisulcatus juveniles with an average weight of 2.4 gm were stocked at 3, 6, 9, 12, and 15 pcs/m2 in ten outdoor earthen ponds (each 4000 m2 area and 80 cm depth). Juveniles were fed for 16 weeks on two experimental diets containing 52 and 42 % dietary protein for the first 8 weeks and the next 8 weeks, respectively. Growth performance of the experimental shrimp was improved by decreasing stocking density. The average final weights were 18.53, 16.97, 15.98, 15.35, and 15.04 gm for shrimp stocked at 3, 6, 9, 12, and 15 pcs/ m2, respectively. The significant difference (P < 0.05) of gain, average daily gain (ADG) and specific growth rate (SGR %) were observed for shrimp stocked at 3 pcs/m2 grew significantly (P < 0.05). However, no significant differences were showed among growth of shrimp stocked at 9, 12, and 15 pcs/m2 respectively. Feed conversion ratio (FCR) was increased significantly (P < 0.05) by increasing the stocking density. Values of protein efficiency ratio (PER), protein productive value (PPV %) and energy utilization (P <0.05) decreased significantly by increasing the stocking density of marine shrimp. Production of cultured shrimp increased significantly (P < 0.05) (497.8, 865.2, 1178.4, 1435.9, and 1638.0 kg/ ha) with an increase in stocking density 3, 6, 9, 12, and 15 pcs/m2, respectively. Finally it could be concluded that growth performance of marine shrimp Penaeus semisulcatus decreased with increasing stoking density otherwise, the production increased .
Penaeid shrimp reared in eutrophic pond water grow significantly faster than shrimp in clear well water, and this growth enhancement is especially pronounced in postlarval shrimp. The objective of this study was to determine if the nutritional benefits of pond water could supplement a lower protein feed for postlarval Pacific white shrimp Litopenaeus vannamei. Sixteen 230-L tanks were stocked with 10-d postlarvae at a density of 350 shrimp/tank. Four treatments (four replicates/treatment) were tested for 6 wk and consisted of: 1) shrimp grown in well water and fed a commercially available 45%-protein feed (W/45); 2) shrimp grown in pond water and fed the same 45%-protein feed (P/45); 3) shrimp grown in well water and fed a commercially available 52%-protein feed (W/ 52); and 4) shrimp grown in pond water and fed the same 52%-protein feed (P/52). At the end of the experiment, mean weight gain (+/- SE) for shrimp in pond water (1.85 +/- 0.03 g) was significantly greater (P < 0.0001) than shrimp in well water (0.98 +/- 0.10 g). Mean weight gain for shrimp fed the 52%-protein feed (1.56 +/- 0.13 g) was significantly greater (P < 0.0001) than shrimp fed the 35%-protein feed (1.26 +/- 0.20 g). In addition, there was a significant interaction effect between water source and feed (P < 0.0001). Mean weight gain for shrimp in the W/52 treatment (1.23 +/- 0.04 g) was 68% greater than shrimp in the W/45 treatment (0.73 +/- 0.03 g). However, mean weight gain for shrimp in the P/52 treatment (1.90 +/- 0.03,a) was only 5% greater than shrimp in the P/45 treatment (1.80 +/- 0.04 g). These results suggest that organically rich pond water provides postlarval shrimp with sufficient nutrients to compensate for nutritional deficiencies associated with a lower protein feed.
This study characterized and quantified the dissolved nitrogen (N) waste from shrimp (Penaeus monodon) feeding. The subsequent utilization of the dissolved N (DN) compounds by the microbial community in shrimp pond water was also examined. There were three main sources of soluble N from feeding; gill excretion, leaching from formulated feed, and leaching from shrimp faeces. The main source of DN was ammonia excreted from shrimp gills. However, there was also a significant amount of DN leached from feed and faeces over the course of a few hours. Most of this was in the form of dissolved organic N (DON) compounds. In the case of feed, a significant proportion of this was dissolved primary amines (I)PA. 23%) whilst in faeces, it was urea (26%). Urea leached from shrimp faeces was rapidly utilized by the microbial community in pond water. However, other DON compounds appeared to be less bioavailable. Dissolved organic N leached from formulated feed appeared to be less effectively utilized by the microbial community and is likely to accumulate in pond water. Dissolved organic N leachates from formulated feed and faeces are, therefore, likely to have a significant impact on water quality in shrimp ponds, both by the accumulation of DON, and stimulation of the growth of the microbial community. There is, therefore, considerable scope to improve water quality, and hence reduce nutrient discharges from shrimp fanning, by reducing overfeeding, and improving feed retention by shrimp.