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Boletín de Investigaciones Marinas y Costeras - INVEMAR

Print version ISSN 0122-9761

Bol. Invest. Mar. Cost. vol.49 no.1 Santa Marta Jan./June 2020

https://doi.org/10.25268/bimc.invemar.2020.49.1.774 

Research Articles

Effect of Bacillus firmus C101 on the growth of Litopenaeus vannamei Boone (White Shrimp) post-larvae, and Brachionus plicatilis s.s. Müller (Rotifer)

Jordan Steven Ruiz-Toquica1 

Laura Milena Becerra-Real1 

Luisa Marcela Villamil-Díaz2  *  

1. Fundación Universidad de Bogotá Jorge Tadeo Lozano. Facultad de Ciencias Naturales e Ingenierías. Programa de Biología Marina. Bogotá, Colombia. jordansteven6@gmail.com; laura_milena'990@hotmail.com

2. Doctorado en Biociencias, Facultad de Ingeniería. Universidad de La Sabana. Chía, Colombia.


ABSTRACT

The growing demand for aquaculture protein suggests seeking biotechnological alternatives that improve the cultivation of species of commercial interest. In this study, Bacillusfirmus C101 was evaluated as a growth promoter and probiotic potential, which was characterized and subsequently administered (106 CFU mL-1 * day) in post-larvae of white shrimp (Litopenaeus vannamei) and rotifers (Brachionusplicatilis sensu stricto). B. firmus C101 was observed to have the tolerance to bile salts, strong phosphatase activity, and antimicrobial activity against pathogens such as Vibrio alginolyticus and Aeromonas hydrophila, among others. On the other hand, after its administration for three weeks to postlarvae of shrimp, it caused a significant increase (p < 0.05) in the specific growth rate (TEC = 3.8 ± 0.7 % day-1), the increase in daily weight (ADG = 1.5 ± 0.1 mg day-1) and in the feed conversion rate (TCA = 1.5 ± 0.1 %) compared to controls without the addition of this bacterium (sterile PBS). Likewise, the administration of B. firmus C101 (106 CFU mL1 * day) to rotifers caused an increase in the population growth rate (TC = 20.2 ± 1.5 % day1), fertility (F = 0.4 ± 0.03 eggs individuals-1) and productivity (R = 16.0 ± 0.7 individuals mL-1 * day) after 48 h of culture. Based on the above and in comparison with other studies, B. firmus C101 is suggested as a potential probiotic and growth promoter in shrimp postlarvae, and as the first report of the effect of its administration in rotifers. However, studies on the possible mechanisms of action are required, as well as tests on a pilot and commercial scale to validate these results and their possible transfer to the productive sector.

KEYWORDS: probiotic; growth promoter; Bacillusfirmus; white shrimp; rotifers

RESUMEN

La creciente demanda de proteína acuícola sugiere buscar alternativas biotecnológicas que mejoren el cultivo de especies de interés comercial. En este estudio se evaluó Bacillus firmus C101 como promotor del crecimiento y potencial probiótico, el cual fue caracterizado y posteriormente administrado (106 UFC mL-1 * día) en poslarvas de camarón blanco (Litopenaeus vannamei) y en rotíferos (Brachionusplicatilis sensu stricto). Se observó que B. firmus C101 tiene tolerancia a sales biliares, fuerte actividad fosfatasa y actividad antimicrobiana frente a patógenos como Vibrio alginolyticus y Aeromonas hydrophila, entre otros. Por otro lado, tras su administración por tres semanas a poslarvas de camarón causó un aumento significativo (p < 0,05) en la tasa específica de crecimiento (TEC = 3,8 ± 0,7 % día-1), el incremento de peso diario (ADG = 1,5 ± 0,1 mg día-1) y en la tasa de conversión alimenticia (TCA = 1,5 ± 0,1 %) en comparación con los controles sin adición de esta bacteria (PBS estéril). Así mismo, la administración de B. firmus C101 (106 UFC mL-1 * día) a rotíferos causó un aumento en la tasa de crecimiento poblacional (TC = 20,2 ± 1,5 % día-1), fecundidad (F = 0,4 ± 0,03 huevos individuos-1) y productividad (R = 16,0 ± 0,7 individuos mL-1 * día), después de 48 h de cultivo. Con base en lo anterior y en comparación con otros estudios, se sugiere a B. firmus C101 como potencial probiótico y promotor del crecimiento en poslarvas de camarón, y como primer reporte del efecto de su administración en rotíferos. No obstante, se precisan estudios sobre los posibles mecanismos de acción, y pruebas a escala piloto y comercial para validar estos resultados y su posible transferencia al sector productivo.

PALABRAS CLAVE: probiótico; promotor del crecimiento; Bacillus firmus; camarón blanco; rotíferos

INTRODUCTION

In aquaculture, probiotics are defined as "live microorganisms that, when administered in appropriate amounts, provide benefits to the health of the hosts" (FAO, 2001; Bajagai et al., 2016). These microorganisms are capable of secreting antagonistic substances, growth factors, essential nutrients, and digestive enzymes, which promote and improve digestion, growth, immune response, and the stress response (Nimrat et al., 2013; Hoseinifar et al., 2017). For their application in cultured aquatic organisms, they must meet certain characteristics such as a high tolerance to bile salts, growth at wide ranges of temperature, salinity, and pH, as well as the ability to adhere to mucus in the intestinal tract and not show factors of virulence (Kazuñ and Kazuñ, 2014; Dawood et al., 2018).

Currently, numerous bacterial strains of the Bacillus genus are used as probiotics to promote growth in cultured aquatic organisms (Kumar et al., 2016; Ringo and Song, 2016), especially in larval stages (Newaj-Fyzul et al., 2014; Vieira et al., 2016; Zorriehzahra et al., 2016). In this way, the effect of B. firmus strains as growth and survival promoters has been previously described in white shrimp (Litopenaeus vannamei) (Yuniarti et al. , 2013; Barman et al. , 2017), a species of commercial interest that is currently affected by bacterial diseases, especially during the larval stages (Flores-Miranda et al., 2012; López León et al., 2016).

Likewise, probiotic bacteria have been shown to have a positive effect on the productivity, population growth and fertility of organisms such as rotifers of the genus Brachionus sp. (Najmi et al., 2018), which are used as live food in the cultivation of aquatic organisms in larval stages (Gatesoupe, 1991; Hirata et al., 1998; Zink et al., 2013). Consequently, the growing demand for biosecurity in the production chain has required the use of biotechnological strategies that avoid the inappropriate use of antibiotics, and that allow improving the physiological response in the larval and post-larval stages of species such as white shrimp, as well as the quality and parameters of rotifer cultures (Vieira et al., 2016; Li et al., 2017). Therefore, the present study presents the characteristics of B. firmus C101 as a growth promoter and possible probiotic candidate for postlarvae of white shrimp (L. vannamei), and in the culture of rotifers (B. plicatilis s.s.).

MATERIALS AND METHODS

Obtaining bacterial strains and maintenance in culture media

C101 was isolated from the gills of healthy Cobia larvae (Rachycentron canadum). For the assays, C101 was grown on trypticase soy broth and agar (TSA and TSB, Becton Dickinson™) with 1 % NaCl and on a marine agar (Zobell™). Vibrio alginolyticus was obtained from a mortality episode of Horse mackerel (Caranx hippos) from a local aquarium and V. harveyi BB120 (Bassler et al., 1997), both were grown on thiosulfate-citrate-bile-sucrose agar (Becton Dickinson™), blood-lamb agar (Becton Dickinson™) and nutrient agar (Sigma-Aldrich). Aeromonas hydrophila, Edwardsiella tard, and Streptococcus agalactiae were isolated from mortalities of Tilapia (Oreochromis spp.) and were obtained from the collection of microorganisms of the Veterinary Faculty of the National University of Colombia and cultured in TSA, TSB, and sheep-blood media. For long-term preservation, the bacteria were cultivated in TSB broth and stored at -80 °C with 20 % glycerol (Murillo and Villamil, 2011).

C101 Characterization

Morphology was described through light microscopy (Olympus CX22) and the Gram character through staining (Claus, 1992). Catalase and oxidase (tetramethyl-para-phenylenediamine) tests were performed and the enzyme profile was obtained with the API-ZYM® kit (Biomérieux). C101 growth was evaluated at different temperatures (4, 28, 36, and 40 °C), salinities (0, 1, and 6.5 % NaCl), pH (2, 4, 6, 7, and 8), and bile salts (0.5, 1, 3 and 5 %). Identity was determined from partial sequencing of the 16S rRNA gene with primers 63f (5'-CAGGCCTAACACATGCAAGTC-3') and 1387r (5'-GGGCGGWGTGTACAAGGC-3 '). The readings were analyzed with the BLASTn algorithm, and a minimum of 98.65 % similarity was taken into account for the species assignment (Valenzuela-González et al., 2015).

Growth was evaluated according to Villamil and Esguerra (2017). In 50-well plates. 50 μl of the fresh culture (106 CFU mL-1) and 50 μl of the liquid medium were mixed in triplicate and incubated at 28 °C. Growth was monitored for 72 h and the optical density (OD) (absorbance or Abs at 600 nm) was read on the Modulus Microplate Reader spectrophotometer. Also, the viability and survival in seawater were estimated by re-suspending 106 CFU mL-1, incubating for 24 h at 28 °C, and performing a plate count (CFU mL-1).

Antimicrobial activity assay

The C101 extracellular products (ECPs) were extracted following the methodology described by Cabo et al. (1999) and Villamil et al. (2010) with slight modifications. For this, C101 was cultivated in broth for 24 h, the culture was centrifuged in three cycles of 3000 rpm x 15 minutes, and the supernatant (containing the ECPs) was recovered and then filtered at 0.2 μm. Subsequently, in a 96-well plate, 50 μl of the filtrate and 50 μl of the fresh pathogen culture (106 CFU mL-1) were added in triplicate. The plate was incubated at 28 °C for 24 h and the OD reading was performed. 50 μl of the culture medium was included as control with the ECPs. The change in the OD of the cultures of the pathogenic strains was expressed as a percentage of growth inhibition.

Obtaining and maintaining shrimp and rotifers

The postlarvae (PLs) of white shrimp (L. vannamei) in stage PL-21, and the rotifers (B. plicatilis s.s.) were provided by CENIACUA (Cartagena, Colombia), transported to the facilities of the Jorge Tadeo Lozano University (Santa Marta, Colombia), and acclimatized in ponds with continuous aeration. The postlarvae were placed in a glass aquarium with 32 L of filtered seawater (35 salinity and 28 °C), at a density of 16 PLs L-1, and were fed with ground Nicovita concentrate (size 500 μm and donated by CENIACUA) in three daily rations (10 % of body weight) (Membreño et al., 2014). The conditions were stable, with continuous aeration, 80 % water changes day-1, and photo-period of 12 h light and 12 h darkness. The massive culture of rotifers (B. plicatilis s.s.) was kept in filtered and sterile seawater (35 salinity and 28 °C), with stable conditions of aeration, continuous lighting, and 100 % water changes day-1, sieving them per 100 and 60 μm, and feeding them twice a day with Nanochloropsis sp. (106 microalgae mL-1).

Evaluation of B. firmus C101 as a probiotic for shrimp and rotifers

C101 was grown in TSB broth for 24 hr at 28 °C. The culture was centrifuged at 6000 rpm for 15 min at 4 °C, the pellet was washed three times with sterile saline solution (0.9 % NaCl), and resuspended in 15 ml of sterile Phosphate Buffer (1X PBS). The initial concentration of the liquid suspension was estimated by spectrophotometry (Abs at 600 nm), and verified by direct plate count and reported as the number of colony-forming units per unit volume (CFU mL-1).

Evaluation for shrimp postlarvae

Three plastic containers were placed for the treatment with C101 and three for the control (sterile PBS). In each container with 2 L of ultra-filtered seawater, 30 PLs of shrimp were sown (for a total of 180 PLs). All the culture and feeding conditions were kept stable, making 100 % water changes day-1. The C101 liquid suspension was added daily in the container water (Luis-Villaseñor et al., 2011) at a final dose of 106 CFU mL-1 * day (Zhou et al., 2009). PBS was added as a control, without the presence of C101. The experiment lasted three weeks.

At the beginning of the experiment, data on dry weight (samples incubated at 65 °C for 48 h) and fresh length of shrimp PLs (n = 10) were taken. At the end of the experiment, these same data were taken from both the controls (n = 30, that is, 10 from each replica) and the postlarvae treated with C101 (n = 30). The fresh length was determined by stereoscopy, while dry weight was measured on a digital scale (Sartorius, Cubis®). Additionally, at the end of the experiment, the number of live PLs was also determined before taking samples for analysis. The following indices were calculated with the obtained data: Weight gain (GP) (%) = (Wf - Wi)/Wi * 100, Height gain (GT) (%) = (Lf - Li)/Li * 100, Specific Growth Rate (TEC) (% day-1) = (LnWf - LnWi)/t * 100, Average Weight Increase per Day (ADG) (mg day-1) = (Wf - Wi)/t, and the Food Conversion Rate (TCA) = R/(Wf - Wi); where W is average weight, L is the average length, t is the duration time (in days) of the experiment, and R is the daily ration of the concentrated food (Abd El-Rhman et al., 2009; Nimrat et al. , 2013). The survival rate of the organisms was calculated as follows: Survival (%) = (nf/ni) * 100, where ni is the total number of individuals in each container at the beginning of the experiment and nf at the end (Nimrat et al., 2012).

Evaluation for rotifers

The rotifers were placed in Erlenmeyer with 80 ml of ultra-filtered and sterile seawater, at an initial density of 65 ± 4.2 mL-1 rotifers. The addition of B. firmus C101 was carried out for two days (one added daily, that is, every 24 h), to a final concentration of 106 CFU mL-1 * day. Both the C101 treatment and the control (sterile culture medium) were performed in triplicate. Also, all the culture and feeding conditions were constant with 100 % day-1 water replacements.

The effect of C101 administration on rotifers was determined by population growth, as measured by the change in the density of individuals, females, males, and eggs. For this, 1.0 ml of each culture was taken as a sampling unit and a count was made by light microscopy using the Edmonson method (count/volume) on a Sedgewick Rafter plate (Biologik®). Also three aliquots were taken per treatment to take into account the variability of the aliquots. All measurements were made in triplicate, and the following indices were calculated: Population growth rate (TC) (% day-1) = (Ln Nt - Ln No/t * 100), Fertility (F) (individual eggs.-1) = (# Eggs/# Females) and Productivity (R) (indiv. ML-1 * day) = (Nt - No/t * 100); where Nt is the density of rotifers at time t, No is the initial density and t is the supply time in the crop (Cisneros, 2011, 2012).

Evaluation of the number of total cultivable bacteria associated with shrimp and rotifers

After the addition of C101, a count of total heterotrophic bacteria (BT) was performed from the tissues of the post-larvae of shrimp and rotifers. For this, an individual (1.0 ml in the case of rotifers) was taken from each replicate of both the treatment and the control. The samples were washed with abundant sterile seawater and were macerated under sterile conditions. This macerate was resuspended in 0.5 ml of 1X PBS and then serially diluted to 10-6 according to Villamil et al. (2010) and Murillo and Villamil (2011). Then 0.1 ml of dilutions 10-3 to 10-6 were plated in triplicate on marine agar (Zobell™). The plates were incubated at 28 °C for 24 h, and at the end, the number of colonies forming units per milligram of tissue (CFU mg-1) and rotifer (CFU rotifer-1) was determined. All counts were carried out in triplicate.

Statistic analysis

Data were expressed as average ± standard error (ES). Assumptions of normality were tested with the Shapiro-Wilk test and homogeneity of variances (homoscedasticity) with Levene's test. One-way analysis of variance (ANOVA) was performed to test statistical differences (p < 0.05). Also, a Duncan multi-range test was used to compare the means when the differences were detected with the ANOVA. All statistical analyzes were carried out in SPSS 15.0 and Statgraphics Centurion XV for Windows (California, USA).

RESULTS

C101 characterization

The morphological and physiological characterization of C101 is described in Table 1. This isolate was identified as Bacillus firmus (98.8 % identity), and showed growth at different temperatures (between 4 and 40 °C), salt concentrations (between 0 and 6.5 % NaCl), and concentrations of bile salts (between 0.5 and 5 %), but no growth was observed at extreme pH (< 6 and > 8), or below 4 °C. The ideal growth of C101 was observed at 28 °C, 1 % NaCl and pH 7.4, conditions that were used in all subsequent tests for its cultivation. Regarding growth, it was observed that it continues to grow after 24 h and up to 72 h of incubation at a rate of 0.0191 ± 0.003 abs h-1, and also, it can survive in seawater (28 °C and 35 of salinity) with counts of 4.2 ± 1.4 x 106 CFU mL-1 of water after 24 h incubation.

Table 1 Morphological and physiological characteristics (growth) of Bacillus firmus C101. 

* There was growth: +. There was no growth: -

Enzymatic and antimicrobial activity of C101

The enzymatic activity of B. firmus C101 is shown in Table 2. In summary, B. firmus C101 is catalase positive, oxidase negative, showed intense acid and alkaline phosphatase activity, moderate lipase/esterase (C4 - C8) and trypsin/α-chymotrypsin, and shows no activity in the hydrolysis of disaccharides. Additionally, the ECPs of B. firmus C101 showed growth inhibitory activity of different pathogens, turning out to be more active against V. alginolyticus (49.7 %), A. hydrophila (47.9 %) and S. agalactie (46.8 %) and to a lesser extent vs. E. tarda (39.6 %) and V. harveyi BB120 (12.3 % inhibition).

Table 2 Bacillus firmus C101 enzymatic activity. 

* There was no activity: -. Weak activity: W. Moderate activity: +. Intense activity: ++. Very intense activity: +++.

Evaluation of B. firmus C101 as a probiotic for shrimp and rotifers

Evaluation for shrimp postlarvae

The initial length and average weight of the postlarvae (PL-21) of white shrimp (L. vannamei) were 70.2 ± 2.1 mm and 12.3 ± 0.02 mg respectively. After the administration of B. firmus C101 (Figure 1), a significant increase (p < 0.05) was evident for all growth indicators concerning the control treatment (Table 3).

Figure 1 Postlarvae (PLs) of shrimp Litopenaeus vannamei administered with Bacillus firmus C101. a) PLs before addition, b) PLs from control (no addition), c) y d). PLs administered with B. firmus C101 (Replica 1 and 2). 

Table 3 Growth and survival indicators of white shrimp (Litopenaeus vannamei) postlarvae administered with Bacillus firmus C101. 

Data were expressed as average ± ES. a) There were significant differences (p < 0.05) in the averages of the treatment with C101 for the control. b) There were no significant differences (p > 0.05) for the control. Length: length, GT: height gain, TEC: specific growth rate, GP: weight gain, ADG: average daily weight increase, TCA: feed conversion rate, S: survival.

In general, an increase was observed in the length and weight of the postlarvae with the B. firmus C101 treatment, compared to those of the control. There was a marked effect on the specific growth rate (TEC = 3.8 ± 0.7 % day-1), the increase in daily weight (ADG = 1.5 ± 0.1 mg day-1) and the feed conversion rate (TCA = 1.5 ± 0.1 %), which was significantly lower (p = 0.0011) in relation to the control. Furthermore, no negative effects were observed in the survival rate (S > 90 %) of the postlarvae after the addition of B. firmus C101, nor significant differences concerning the control (p > 0.05; p = 0.3793).

Evaluation for rotifers

The initial densities in the cultures were 65.0 ± 4.2 indiv. mL-1, 44.7 ± 3.8 females mL-1, 20.3 ± 2.3 males mL-1, and 25.0 ± 3.2 eggs mL-1, and the indicators of population growth are described in Table 4. It was observed that for the number of total individuals and of females there were no differences (p > 0.05) between the initial time and the final time in the control. However, in the treatment with B. firmus C101, differences were found (p < 0.05). A significant decrease (p < 0.05) in the number of eggs in the control was also observed in the final time. The number of males was significantly reduced at the end of the experiment in control and treatment. On the other hand, a significant increase was observed in the number of individuals (p = 0.0101), females (p = 0.0009), and eggs (p = 0.00001) after the administration of B. firmus C101 concerning the control. Thus, it was observed that the effect of B. firmus C101 was more evident for the total number of rotifers (97.0 ± 3.4 indiv. mL-1) and for that of females (87.7 ± 1.9 females mL-1) and concerning the control. Population growth rates (TC), fertility (F), and productivity (R) were also significantly higher (p < 0.05) after the administration of B. firmus C101, and compared to that obtained for the control.

Table 4 Population growth parameters of cultures of rotifers (Brachionus plicatilis s.s.), administered without probiotic (control) and with Bacillus firmus C101, cultivated for 48 h. 

Data were expressed as average ± ES. a) There were significant differences between the initial and final time (p < 0.05). b) There were no significant differences between the initial and final time (p > 0.05). c) There were significant differences in the means of the parameters/indices concerning the control (p < 0.05). d) There were no significant differences in the mean of the parameters concerning the control ♀ females, ♂ males, TC: population growth rate, F: fertility (egg-ratio), and R: productivity.

Evaluation of the number of total cultivable bacteria associated with shrimp and rotifers

The values of total cultivable bacteria (BT) counts from the tissues of post-larvae of white shrimp and rotifers are shown in Figure 2. In both cases, a significant increase (p < 0.05) was observed in the count in BT plate after administration of B. firmus C101, concerning those obtained for the control treatment. Regarding shrimp postlarvae, average counts of 4.9 ± 0.4 x 107 CFU mg-1 tissue were obtained with the addition of B. firmus C101. For rotifers, the average count was 2.9 ± 0.3 x 105 UCF rotifer-1 after treatment with B. firmus C101.

Figure 2 Total bacterial count (BT) in the tissues of shrimp and rotifers PLs. Average + ES is displayed. 

DISCUSSION

Evaluation of B. firmus C101 as a probiotic for shrimp postlarvae

Bacillus genus bacteria have been successful as additives in the diet of cultured aquatic organisms (Kumar et al., 2016; Ringe and Song, 2016), improving water quality (Zokaeifar et al., 2014; Tang et al., 2016) and evidencing a potential effect on the growth and survival in larval stages of different marine species of commercial interest (Vieira et al., 2016; Zorriehzahra et al., 2016). In white shrimp (Litopenaeus vannamei) culture, the positive effect of different species of this genus (ie Bacillus cereus, B. subtilis, B. pumilus, B. megaterium, B. coagulans and B. licheniformis) has been demonstrated when administered at different doses, and in freeze-dried food (108 CFU g-1) (Wang, 2007), micro-encapsulated (109 CFU g-1) (Nimrat et al., 2012), pellets (1010 CFU g1) (Zokaeifar et al., 2012; Sadat Hoseini Madani et al., 2018), liquid suspensions (106 CFU mL-1 directly in water) (Wang et al., 2016), bio-flocs (109 CFU mL-1) (Ferreira et al., 2015; Pacheco-Vega et al., 2018) and in mixture with other bacteria (107 and 109 CFU g-1) (Bernal et al., 2017; Bachruddin et al., 2018).

Furthermore, the effect of B. firmus strains on growth and resistance in tiger shrimp (Penaeus monodon) (Raghu et al., 2016; Kolanchina et al., 2017) and in L. vannamei (Yuniarti et al., 2013; Barman et al., 2017) has been previously demonstrated. In this study, it is reported that at a dose of 106 CFU mL-1 of B. firmus C101, administered directly in the water and without mixing with other strains, a significant increase in the growth and yield of the PLs of white shrimp is obtained (L. vannamei).

Compared to other studies carried out in different stages of L. vannamei (from nauplius to juveniles), the addition of Bacillus sp. strains has a marked effect on the feed conversion rate (TCA %), showing values below 1.8 % and even some equal to or less than 1.5 % (Table 4). These low values indicate rapid growth and good use of food (Membreño et al., 2014), which in turn corresponds to the height and weight gain obtained in this study. However, for direct comparisons of the effect of probiotics, the form of addition (individual or in a mixture), dose, route, and duration of administration should be considered. Thus, with the addition of B. firmus C101 directly in the culture water of the shrimp postlarvae, and with a duration of three weeks, the effect on specific growth rates, daily weight increase, and feed conversion is highly promising if it is compared with that obtained in other studies according to the type of probiotic (simple or mixed), the dose, the route of administration, and its duration (Table 5).

Table 5 Some studies of the effect of the administration of bacteria of the genus Bacillus sp. in white shrimp (Litopenaeus vannamei) of different stages. 

Data are expressed as mean ± SD (standard deviation). TEC = specific growth rate, ADG = average daily weight gain, and TCA = feed conversion rate.

Growth, resistance to changes in temperature, salinity, and the physiological conditions of the gastrointestinal tract (TGI) of organisms, which is slightly alkaline (pH ~ 8.0) and with a high concentration of bile salts (Heisterkamp et al., 2016), are characteristics that a good probiotic candidate must meet (Balcázar et al., 2006; Reddy et al., 2018). Following the above, the physiological profile of B. firmus C101 and the fact that some strains of B. firmus can adhere and form biofilms in the intestinal tract of aquatic organisms (Kesarcodi-Watson et al., 2008) suggest that there is a high probability of TGI colonization of white shrimp postlarvae and a high probability of survival under these conditions, therefore it would be pertinent in future researches to carry out analyzes of intestinal microbial diversity with independent culture techniques.

Additionally, the biochemical profile of B. firmus C101 suggests a high enzymatic activity of hydrolases such as lipases/esterases, chymotrypsins and phosphatases, which may be beneficial for the host, since several studies suggest that once these bacteria establish themselves in the TGI can secrete these enzymes, and in this way contribute to the degradation and absorption of essential nutrients that improve digestion and the use of food (Castex et al., 2008; Angelakis, 2017; Gobi et al., 2018). Other research indicates that the production of phosphatases by probiotics such as B. subtilis increases the absorption of elements such as calcium, iron, and inorganic phosphorus in fish species such as Epinephelus coioides and Silurus soldatovi (Liu et al. , 2010), and facilitates the elimination of phosphate esters and intestinal detoxification, which avoids inflammation problems and infections in the TGI that can lead to stress and death of the host (Lallès and Suescún, 2014).

On the other hand, it is known that some strains of Bacillus sp. show significant antagonistic activity against potential pathogens such as A. hydrophila (Yi et al., 2018), Edwarsiella tard (Ran et al., 2012), V. harveyi (Zokaeifar et al., 2012), V. parahaemolyticus (Bernal et al., 2017) and Streptococcus sp. (Liu et al., 2012), which affect the larviculture of aquatic animals (López León et al., 2016). This study highlights the inhibitory activity of the B. firmus C101 ECPs against some of these potential pathogens. However, subsequent studies on this mode of action are required as some authors suggest that this activity may be due to the secretion of compounds such as antibiotics, siderophores, bacteriocins, proteases, reactive forms of oxygen (i.e. H2O2) and lysozymes (Khochamit et al., 2015; Newaj-Fyzul and Austin, 2015; Wang et al., 2015), which could be present in the ECPs of this candidate.

Based on all of the above, B. firmus C101 is proposed as a potential probiotic candidate and growth promoter in the larviculture of white shrimp (L. vannamei), especially in post-larval stages and in closed culture systems. However, studies are required on the possible mechanisms of action of this candidate, the ability to adhere to TGI, and the effect on crop water quality.

Evaluation of B. firmus C101 as a probiotic for rotifers

In recent decades, several studies have indicated that lactic acid bacteria (i.e.: LactoBacillus plantarum, L. delbrueckii, L. acidophilus, L. rhamnosus) and of the genus Bacillus (i.e.: B. subtilis, B. megaterium, B. licheniformis, B. pumilus) have a positive effect on the yields of rotifer crops. Therefore, it has been observed that mixed cultures of these bacteria increase their density (rotifers mL-1), beneficial bacterial load (CFU rotifer-1), and nutritional composition (Hirata et al., 1998; Douillet, 2000; Najmi et al., 2018). In a previous publication (Murillo and Villamil, 2011), a remarkable effect on the growth and regulation of the B. plicatilis microbiota treated with B. subtilis CCBM-64 (107 CFU mL-1) was reported. Another study showed that mixtures of B. subtilis, B. licheniformis, B. megaterium and B. laterosporous (108 CFU L-1 each) have a direct effect on the fecundity of rotifers (egg-ratios from 0.30 to 48 h of treatment) (Zink et al., 2013). In agreement, the data of the present study suggest a remarkable effect of Bacillus firmus C101 on population growth, fertility, and productivity of B. plicatilis s.s., when administered at a dose of 106 UCF mL-1, after 48 h. However, direct comparisons of population dynamics between studies of rotifers can be complicated due to the use of different strains, mixtures, delivery mechanisms, and/or preconditions or during cultivation as the type, and quantity of microalgae supplied as a primary food (Snell et al., 1983; Abd Rahman et al., 2018).

Among the benefits of enriching rotifer cultures with this type of probiotics is modulation of the endogenous microbiota of the digestive tract, which includes increasing the load of beneficial bacteria, decreasing the load of pathogenic bacteria (Makridis et al., 2000; Planas et al., 2004); and the secretion of metabolites and essential nutrients such as vitamins (biotin and VitB12), amino acids, and growth factors (Yoshimatsu and Hossain, 2014). This contributes to the improvement of the nutritional composition (Rollo et al., 2006), reproduction rate (Qi et al., 2009), and growth rate (Rombaut et al., 1999) of rotifers. In the present study, it was observed that the administration of B. firmus C101 in crops resulted in an increase in population densities, which in turn evidences a positive effect of this probiotic candidate. However, future research on its nutritional profile is required, and an analysis of the bacterial community that in turn allows determining whether the increase in the number of total bacteria is due to the incorporation of this candidate in the native microbiota, and not to an increase in the bacterial load of possible pathogens (i.e. species of the genus Vibrio) in the tissues of the rotifers.

The importance of the present contribution in this study is that the improvement of rotifer cultures through these strategies has turned out to be an important tool for the transfer of probiotic candidates to culture organisms in larval stages (Jamali et al., 2015). Thus, these organisms can take advantage of the multiple benefits provided by probiotic bacteria, such as the decrease in diseases that affect larvae (Jeeja et al., 2011; Loka et al., 2016). For this reason, future studies are necessary to prove that the enriched rotifers can serve as a vehicle in the transfer of this probiotic candidate to the larvae of culture organisms such as shrimp, as some studies suggest that once these probiotic candidates establish themselves in the tissues and the digestive tract of rotifers (or any other type of live food) (Kostopoulou and Center, 2012), these candidates and their products can effectively reach the TGI of the larvae, which feed on these enriched live prey (Ringe et al., 2003, 2007).

CONCLUSIONS

It is possible to confirm the important role of Bacillus firmus C101 as a growth promoter in post-larval stages of white shrimp (L. vannamei) and in the improvement of rotifers population parameters (B. plicatilis s.s.), as the results presented here indicate a positive effect of the direct addition of this strain in experimental cultures. Although there are currently numerous reports on the probiotic effect of different Bacillus sp., the present study can be considered as the first report of the effect of individual administration of B. firmus in rotifers. However, additional studies are required on the possible mechanisms of action of this probiotic candidate, and pilot and commercial-scale tests to validate these results and their possible transfer to aquaculture companies.

ACKNOWLEDGEMENTS

The authors thank the Jorge Tadeo Lozano University Foundation (headquarters: Santa Marta, Colombia) for providing the facilities for the execution of the experiments, Ceniacua (Cartagena, Colombia) for the donation of the experimental organisms, and Colciencias for financing the macroproject (code 6507-502-27286), to María Angélica Martínez Silva and Lina María Mejía Quiñones for their contribution in some experiments, and the University of La Sabana for their support in bibliographic material

BIBLIOGRAFÍA/LITERATURE CITED

Abd El-Rhman, A.M., Y.A.E. Khattab and A.M.E. Shalaby. 2009. Micrococcus luteus and Pseudomonas species as probiotics for promoting the growth performance and health of Nile tilapia, Oreochromis niloticus. Fish Shellfish Immunol., 27: 175-180. http://dx.doi.org/10.1016/j.fsi.2009.03.020. [ Links ]

Abd Rahman, A.R., Z.C. Cob, Z. Jamari, A.M. Mohamed, T. Toda and O.H. Ross. 2018. The effects of microalgae as live food for Brachionus plicatilis (Rotifer) in intensive culture system. Trop. Life Sci. Res., 29: 127-138. [ Links ]

Angelakis, E. 2017. Weight gain by gut microbiota manipulation in productive animals. Microb. Pathog., 106: 162-170. http://dx.doi.org/10.1016/j.micpath.2016.11.002. [ Links ]

Bachruddin, M, M. Sholichah, S. Istiqomah and A. Supriyanto. 2018. Effect of probiotic culture water on growth, mortality, and feed conversion ratio of Vanamei shrimp (Litopenaeus vannamei Boone). IOP Conf. Ser. Earth Environ. Sci., 137. [ Links ]

Bajagai, Y.S., A.V. Klieve, P.J. Dart and W.L. Bryden. 2016. Probiotics in animal nutrition: production, impact and regulation. FAO. [ Links ]

Balcázar, J.L., I. de Blas, I. Ruiz-Zarzuela, D. Cunningham, D. Vendrell and J.L. Múzquiz. 2006. The role of probiotics in aquaculture. Vet. Microbiol., 114: 173-186. [ Links ]

Barman, P., S. Raut, S.K. Sen, U. Shaikh and P. Bandyopadhyay. 2017. Effect of a three-component bacterial consortium in white shrimp farming for growth, survival and water quality management. Acta Biologica Szegediensis, 61(1): 35-44. [ Links ]

Bassler, B.L., E.P. Greenberg and A.M. Stevens. 1997. Cross-species induction of luminescence in the quorum-sensing bacterium Vibrio harveyi. J. Bacteriol., 179: 4043-4045. [ Links ]

Bernal, M.G., R.M. Marrero, Á.I. Campa-Córdova and J.M. Mazón-Suástegui. 2017. Probiotic effect of Streptomyces strains alone or in combination with Bacillus and Lactobacillus in juveniles of the white shrimp Litopenaeus vannamei. Aquac. Int., 25: 927-939. [ Links ]

Bomba, A., R. Nemcová, D. Mudroñová and R Guba. 2002. The possibilities of potentiating the efficacy of probiotics. Trends Food Sci. Technol., 13: 121-126. [ Links ]

Cabo, M.L., M.A. Murado, M.P. González and L. Pastoriza. 1999. A method for bacteriocin quantification. J. Appl. Microbiol., 87: 907-914. [ Links ]

Castex, M., L. Chim, D. Pham, P. Lemaire, N. Wabete, J.L. Nicolas, P. Schmidely and C. Mariojouls. 2008. Probiotic P. acidilactici application in shrimp Litopenaeus stylirostris culture subject to vibriosis in New Caledonia. Aquaculture, 275: 182-193. [ Links ]

Cisneros, R. 2011. Rendimiento poblacional del rotífero nativo Brachionus sp. "Cayman", utilizando diferentes enriquecedores. Ecol. Apl., 10: 99-105. [ Links ]

Cisneros, R. 2012. Crecimiento poblacional del rotifero nativo Brachionus sp."Cayman", al evaluar diferentes microalgas como alimento. Revista cubana de investigaciones pesqueras, 29(1): 18-23. [ Links ]

Claus, D. 1992. A standardized Gram staining procedure. World J. Microbiol. Biotechnol., 8: 451-452. [ Links ]

Dawood, M.A.O., S. Koshio, M.M. AbdelDDaim and H. Van Doan. 2018. Probiotic application for sustainable aquaculture. Rev. Aquac., 11(3): 907-924. [ Links ]

Douillet, P.A. 2000. Bacterial additives that consistently enhance rotifer growth under synxenic culture conditions 2. Use of single and multiple bacterial probiotics. Aquaculture, 182: 241-248. [ Links ]

Fao, W.H.O. 2001. Evaluation of health and nutritional properties of probiotics in food, including powder milk with live lactic acid bacteria. Food Agric. Organ. UN World Heal. Organ. Expert Consult. Rep. [ Links ]

Ferreira, G.S., N.C. Bolívar, S.A. Pereira, C. Guertler, F. do N. Vieira, J.L.P. Mouriño and W.Q. Seiffert. 2015. Microbial biofloc as source of probiotic bacteria for the culture of Litopenaeus vannamei. Aquaculture, 448: 273-279. [ Links ]

Flores-Miranda, M.C., A. Luna-González, Á.I. Campa Córdova, J.A. Fierro-Coronado, B.O. Partida-Arangure, J. Pintado and H.A. González-Ocampo. 2012. Isolation and characterization of infectious Vibrio sinaloensis strainsfrom the Pacific shrimp Litopenaeus vannamei (Decapoda: Penaeidae). Rev. Biol. Trop., 60: 567-576. [ Links ]

Gatesoupe, F.J. 1991. The effect of three strains of lactic bacteria on the production rate of rotifers, Brachionus plicatilis, and their dietary value for larval turbot, Scophthalmus maximus. Aquaculture, 96: 335-342. [ Links ]

Gobi, N., B. Vaseeharan, J.C. Chen, R. Rekha, S. Vijayakumar, M. Anjugam and A. Iswarya. 2018. Dietary supplementation of probiotic Bacillus licheniformis Dahb1 improves growth performance, mucus and serum immune parameters, antioxidant enzyme activity as well as resistance against Aeromonas hydrophila in tilapia Oreochromis mossambicus. Fish Shellfish Immunol., 74: 501-508. https://doi.org/10.1016/j.fsi.2017.12.066. [ Links ]

Heisterkamp, I.M., A. Schramm, D. de Beer and P. Stief. 2016. Direct nitrous oxide emission from the aquacultured pacific white shrimp (Litopenaeus vannamei). In: Drake H.L. (Ed.). Appl. Environ. Microbiol., 82: 4028 LP-4034. [ Links ]

Hirata, H., O. Murata, S. Yamada, H. Ishitani and M. Wachi. 1998. Probiotic culture ofthe rotifer Brachionus plicatilis. Hydrobiologia, 387: 495-498. [ Links ]

Hoseinifar, S.H., M. Dadar and E. Ringe. 2017. Modulation of nutrient digestibility and digestive enzyme activities in aquatic animals: The functional feed additives scenario. Aquac. Res., 48: 3987-4000. [ Links ]

Jamali, H., A. Imani, D. Abdollahi, R. Roozbehfar and A. Isari. 2015. Use of probiotic Bacillus spp. in Rotifer (Brachionus plicatilis) and Artemia (Artemia urmiana) enrichment: effects on growth and survival of Pacific white shrimp, Litopenaeus vannamei, Larvae. Probiotics Antimicrob. Proteins., 7: 118-125. [ Links ]

Jeeja, P.K., Imelda-Joseph and R. Paul Raj. 2011. Nutritional composition of rotifer (Brachionusplicatilis Muller) cultured using selected natural diets. Indian J. Fish., 58: 59-65. http://he.scribd.com/doc/93625862/Jeeja-et-al-2011. [ Links ]

Kazuñ, B. and K. Kazuñ. 2014. Probiotics in aquaculture. Med. Veter., 70: 25-28. [ Links ]

Kesarcodi-Watson, A., H. Kaspar, M.J. Lategan and L. Gibson. 2008. Probiotics in aquaculture: The need, principles and mechanisms of action and screening processes. Aquaculture, 274: 1-14. [ Links ]

Khochamit, N., S. Siripornadulsil, P. Sukon and W. Siripornadulsil. 2015. Antibacterial activity and genotypic-phenotypic characteristics of bacteriocin-producing Bacillus subtilis KKU213: potential as a probiotic strain. Microbiol. Res., 170: 36-50. http://dx.doi.org/10.1016/j.micres.2014.09.004. [ Links ]

Kolanchina, P., P.R. Kumari, T.S. Gnanam, G. John and A. Balasundar. 2017. Performance evaluation of two probiotic species, on the growth, body composition and immune expression in Penaeus monodon. J. Fish. Aquat. Sci., 12: 157-167. http://www.scialert.net/abstract/?doi=jfas.2017.157.167. [ Links ]

Kostopoulou, V. and H. Centre. 2012. The rotifer Brachionus plicatilis: an emerging bio-tool for numerous applications. J. Biol. Res., 17: 97-112. [ Links ]

Kumar, V, S. Roy, D.K. Meena and U.K. Sarkar. 2016. Application of probiotics in shrimp aquaculture: importance, mechanisms of action, and methods of administration. Rev. Fish. Sci. Aquac., 24: 342-368. [ Links ]

Lallès, J.P. and J.P. Suescún. 2014. Intestinal alkaline phosphatase: an enzyme with anti-inflammatory properties. CES Med. Vet. Zootec., 9: 94-103. [ Links ]

Li, E., X. Wang, K. Chen, C. Xu, J.G. Qin and L. Chen. 2017. Physiological change and nutritional requirement of Pacific white shrimp Litopenaeus vannamei at low salinity. Rev. Aquac., 9: 57-75. [ Links ]

Liu, C.H., C.H. Chiu, S.W. Wang and W. Cheng. 2012. Dietary administration of the probiotic, Bacillus subtilis E20, enhances the growth, innate immune responses, and disease resistance of the grouper, Epinephelus coioides. Fish Shellfish Immunol., 33: 699-706. http://dx.doi.org/10.1016/j.fsi.2012.06.012. [ Links ]

Liu, W., X.M. Zhang and L.B. Wang. 2010. Digestive enzyme and alkaline phosphatase activities during the early stages of Silurus soldatovi development. Zool. Res., 31: 627-632. [ Links ]

Loka, J., S.M. Sonali, P. Saha, K. Devaraj and K.K. Philipose. 2016. Use of commercial probiotics for the improvement of water quality and rotifer density in outdoor mass culture tanks. Indian J. Fish., 63: 145-149. [ Links ]

López León, P., A. Luna González, R. Escamilla Montes, M.C. Flores-Miranda and J.A. Fierro Coronado. 2016. Isolation and characterization of infectious Vibrio parahaemolyticus, the causative agent of AHPND, from the whiteleg shrimp (Litopenaeus vannamei). Lat. Am. J. Aquat. Res., 44: 470-479. [ Links ]

Luis-Villaseñor, I.E., M.E. Macías-Rodríguez, B. Gómez-Gil, F. Ascencio-Valle and Á.I. Campa-Córdova. 2011. Beneficial effects of four Bacillus strains on the larval cultivation of Litopenaeus vannamei. Aquaculture, 321: 136-144. [ Links ]

Makridis, P., A.J. Fjellheim, J. Skjermo and O. Vadstein. 2000. Control of the bacterial flora of Brachionus plicatilis and Artemia franciscana by incubation in bacterial suspensions. Aquaculture, 185: 207-218. [ Links ]

Membreño, L., S. Morales and E. Martínez. 2014. Crecimiento de camarones blancos. Rev. Cient. UNAN-León., 5: 103-115. [ Links ]

Murillo, I. and L.M. Villamil-Díaz. 2011. Bacillus cereus and Bacillus subtilis used as probiotics in rotifer (Brachionus plicatilis) cultures. J. Aquac. Res. Dev., 1: 1-5. https://www.omicsonline.org/bacillus-cereus-and-bacillus-subtilis-used-as-probiotics-in-rotifer-brachionus-plicatilis-cultures-2155-9546.S1007.php?aid=2309. [ Links ]

Najmi, N., M. Yahyavi and A. Haghshenas. 2018. Effect of enriched rotifer (Brachionusplicatilis) with probiotic lactobacilli on growth, survival and resistance indicators of western white shrimp (Litopenaeus vannamei) larvae. Iran. J. Fish. Sci., 17: 11-20. [ Links ]

Newaj-Fyzul, A., A.H. Al-Harbi and B. Austin. 2014. Review: Developments in the use of probiotics for disease control in aquaculture. Aquaculture, 431: 1-11. http://dx.doi.org/10.1016/j.aquaculture.2013.08.026. [ Links ]

Newaj-Fyzul, A . andB. Austin . 2015. Probiotics, immunostimulants, plant products and oral vaccines, and their role as feed supplements in the control of bacterial fish diseases. J. Fish Dis., 38: 937-955. [ Links ]

Nimrat, S., P. Tanutpongpalin, K. Sritunyalucksana, T. Boonthai and V. Vuthiphandchai. 2013. Enhancement of growth performance, digestive enzyme activities and disease resistance in black tiger shrimp (Penaeus monodon) postlarvae by potential probiotics. Aquac. Int., 21: 655-666. [ Links ]

Nimrat, S ., S. Suksawat, T. Boonthai and V. Vuthiphandchai . 2012. Potential Bacillus probiotics enhance bacterial numbers, water quality and growth during early development of white shrimp (Litopenaeus vannamei). Vet. Microbiol., 159: 443-450. http://dx.doi.org/10.1016/j.vetmic.2012.04.029. [ Links ]

Pacheco-Vega, J.M., M.A. Cadena-Roa, J.A. Leyva-Flores, O.I. Zavala-Leal, E. Pérez-Bravo and J.M.J. Ruiz-Velazco. 2018. Effect of isolated bacteria and microalgae on the biofloc characteristics in the Pacific white shrimp culture. Aquac. Reports., 11: 24-30. [ Links ]

Planas, M., J.A. Vázquez, J. Marqués, R. Pérez-Lomba, M.P. González and M. Murado. 2004. Enhancement of rotifer (Brachionus plicatilis) growth by using terrestrial lactic acid bacteria. Aquaculture, 240: 313-329. [ Links ]

Qi, Z., K. Dierckens, T. Defoirdt, P. Sorgeloos, N. Boon, Z. Bao and P. Bossier. 2009. Effects of feeding regime and probionts on the diverting microbial communities in rotifer Brachionus culture. Aquac. Int., 17: 303-315. [ Links ]

Raghu, P., M. Rajikkannu, R. Baburajan, A. Deva and R. Nandakumar. 2016. Effect of Bacillus coagulans and B. firmus incorporated probiotic diet on superoxide dismutase activity and catalase activity in Penaeus monodon. World Sci. News., 44: 224-235. [ Links ]

Ran, C., A. Carrias, M.A. Williams, N. Capps, B.C.T. Dan, J.C. Newton, J.W. Kloepper, E.L. Ooi, C.L Browdy, J.S. Terhune and M.R. Liles. 2012. Identification of Bacillus strains for biological control of catfish pathogens. PLoS One 7. [ Links ]

Reddy, S.J., D. Vineela and B.K. Kumar. 2018. Influence of probiotics on growth and development of aquaculture-a review. World J. Pharm. Res., 7: 291-315. [ Links ]

Ringo, E. and S.K. Song. 2016. Application of dietary supplements (synbiotics and probiotics in combination with plant products and p-glucans) in aquaculture. Aquac. Nutr., 22: 4-24. [ Links ]

Ringe, E., R.E. Olsen, T.M. Mayhew and R. Myklebust. 2003. Electron microscopy of the intestinal microflora of fish. Aquaculture, 227: 395-415. [ Links ]

Ringe, E ., R. Myklebust , T.M. Mayhew andR.E. Olsen . 2007. Bacterial translocation and pathogenesis in the digestive tract of larvae and fry. Aquaculture, 268: 251-264. [ Links ]

Rollo, A., R. Sulpizio, M. Nardi, S. Silvi, C. Orpianesi, M. Caggiano, A. Cresci and O. Carnevali. 2006. Live microbial feed supplement in aquaculture for improvement of stress tolerance. Fish Physiol. Biochem., 32: 167-177. [ Links ]

Rombaut, G., P. Dhert, J. Vandenberghe, L. Verschuere, P. Sorgeloos and W. Verstraete. 1999. Selection of bacteria enhancing the growth rate of axenically hatched rotifers (Brachionus plicatilis). Aquaculture, 176: 195-207. [ Links ]

Sadat Hoseini Madani, N., T.J. Adorian, H. Ghafari Farsani and S.H. Hoseinifar. 2018. The effects of dietary probiotic Bacilli (Bacillus subtilis and Bacillus licheniformis) on growth performance, feed efficiency, body composition and immune parameters of whiteleg shrimp (Litopenaeus vannamei) postlarvae. Aquac. Res., 49: 1926-1933. [ Links ]

Snell, T.W., C.J. Bieberich and R. Fuerst. 1983. The effects of green and blue-green algal diets on the reproductive rate of the rotifer Brachionus plicatilis. Aquaculture, 31: 21-30. [ Links ]

Tang, J., Y. Dai, Y. Li, J. Qin and Y. Wang. 2016. Can application of commercial microbial products improve fish growth and water quality in freshwater polyculture? N. Am. J. Aquac., 78: 154-160. [ Links ]

Valenzuela-González, F., R. Casillas-Hernández and E. Villalpando. 2015. The 16S rRNA gene in the study of marine microbial communities. Ciencias Marinas, 41(4): 297-313. [ Links ]

Vieira, F. do N., A. Jatobá, J.L.P. Mouriño, C.C.B. Neto, J.S. Da Silva, W.Q. Seiffert , M. Soares and L.A. Vinatea. 2016. Use of probiotic-supplemented diet on a Pacific white shrimp farm. Rev. Bras. Zootec., 45: 203-207. [ Links ]

Villamil Díaz, L.M., A. Figueras, M. Planas and B. Novoa. 2010. Pediococcus acidilactici in the culture of turbot (Psetta maxima) larvae: Administration pathways. Aquaculture, 307: 83-88. http://dx.doi.org/10.1016/j.aquaculture.2010.07.004. [ Links ]

Villamil Díaz, L.M . y D. Esguerra Rodríguez. 2017. Enterococcus, Myroides y Exiguobacterium: géneros bacterianos con potencial probiótico para el cultivo de tilapia nilótica (Oreochromis niloticus). Acta Biol. Col., 22: 331-339. [ Links ]

Wang, C., X. Song, X. Zhang, S. Zhang, X. Sun, B. Liu, W. Gao and J. Huang. 2016. Effects of adding Bacillus cereus PC465 to rearing water on disease resistance of Litopenaeus vannamei. J. Fish. Sci. China, 23: 146-155. [ Links ]

Wang, Y. 2007. Effect of probiotics on growth performance and digestive enzyme activity of the shrimp Penaeus vannamei. Aquaculture, 269: 259-264. [ Links ]

Wang, Y., Y. Sun, X. Zhang , Z. Zhang, J. Song, M. Gui and P. Li. 2015. Bacteriocin-producing probiotics enhance the safety and functionality of sturgeon sausage. Food Control., 50: 729-735. http://dx.doi.org/10.1016/j.foodcont.2014.09.045. [ Links ]

Yi, Y., Z. Zhang , F. Zhao, H. Liu, L. Yu, J. Zha and G. Wang. 2018. Probiotic potential of Bacillus velezensis JW: Antimicrobial activity against fish pathogenic bacteria and immune enhancement effects on Carassius auratus. Fish Shellfish Immunol., 78: 322-330. https://doi.org/10.1016/j.fsi.2018.04.055. [ Links ]

Yoshimatsu, T. and M.A. Hossain. 2014. Recent advances in the high-density rotifer culture in Japan. Aquac. Int., 22:1587-1603. [ Links ]

Yuniarti, A., D.A. Guntoro and A.M. Hariati. 2013. Response of indigenous Bacillus megaterium supplementation on the growth of Litopenaeus vannamei (Boone), a new target species for shrimp culture in East Java of Indonesia. J. Basic. Appl. Sci. Res., 3: 747-754. [ Links ]

Zhou, X.X., Y.B Wang and W.F. Li. 2009. Effect of probiotic on larvae shrimp (Penaeus vannamei) based on water quality, survival rate and digestive enzyme activities. Aquaculture, 287: 349-353. [ Links ]

Zink, I.C., P.A. Douillet and D.D. Benetti. 2013. Improvement of rotifer Brachionus plicatilis population growth dynamics with inclusion of Bacillus spp. probiotics. Aquac. Res., 44: 200-211. [ Links ]

Zokaeifar, H., J.L. Balcázar, C.R. Saad, M.S. Kamarudin, K. Sijam, A. Arshad and N. Nejat. 2012. Effects of Bacillus subtilis on the growth performance, digestive enzymes, immune gene expression and disease resistance of white shrimp, Litopenaeus vannamei. Fish Shellfish Immunol., 33: 683-689. [ Links ]

Zokaeifar, H ., N. Babaei, C.R. Saad , M.S. Kamarudin , K. Sijam andJ.L. Balcázar . 2014. Administration of Bacillus subtilis strains in the rearing water enhances the water quality, growth performance, immune response, and resistance against Vibrio harveyi infection in juvenile white shrimp, Litopenaeus vannamei. Fish Shellfish Immunol., 36: 68-74. [ Links ]

Zorriehzahra, M.J., S.T. Delshad, M. Adel, R. Tiwari, K. Karthik, K. Dhama and C.C. Lazado. 2016. Probiotics as beneficial microbes in aquaculture: an update on their multiple modes of action: A review. Vet. Q., 36: 228-241. [ Links ]

Received: February 22, 2019; Accepted: February 21, 2020

luisa.villamil@unisabana.edu.co * Autora para correspondencia

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