Executive summary 

A 30-day trial of nursing the P. monodon PLs on a semi-commercial scale was conducted by ShrimpVet Lab at the company’s demonstration farm located in Can Gio, Ho Chi Minh City, Vietnam. Two commercial products of Tiptopp Aquaculture, Tiptopp-gut and Tiptopp-pond, were tested to investigate the growth performance of the shrimp PLs. There was a total of 5 treatments; Control (microalgae in the water), Treatment 1 (microalgae + Tiptopp- AquaG in feed + Tiptopp-pond in water), and Treatment 2 (Tiptopp- AquaG in feed + Tiptopp-pond in water). P. monodon PLs of size ~0.5 g/100 PLs were stocked in 60 m3 plastic-lined tanks at a density of 1000 pcs/m3. Shrimps were fed by following ShrimpVet’s nursery feeding protocol and adjusted following the shrimp’s consumption. Water quality parameters were regularly monitored and kept at the optimal ranges.  

At the end of the trial, the final survival and weight measurements were recorded for further assessments. There were no statistically significant differences in survival or growth performance between the groups. However, numerically highest results were observed in terms of survival, specific growth rate, average daily growth, and FCR in Treatment 2 (Tiptopp- AquaG + Tiptopp-pond). Water quality data were not much different from each group to another. From this trial, it can be noted that the use of probiotics in the nursery phase of P. monodon is applicable and the products of Tiptopp Aquaculture can effectively improve productivity  

Experimental Design 

The trial was composed of 3 treatments; Control (Algae), Treatment 1 (Algae + Probiotics), and Treatment 2 (Probiotics) with 3 replicate each. The summary of the trial design is shown in table 1. Tanks were stocked with 50,000 shrimps /tank which in density is ~1000 pcs/m3.  

Table 1. Trial design summary 

1. Results 

1.1. Growth performance and survival rate 

The growth performance of the shrimps at the end of the trial was not statistically different between the groups. However, there were numerical differences between the groups in terms of ADG, SGR, survival rate, and FCR. It was shown that treatment 2 had the highest performance with the ADG (0.008±0.001 g/day), the SGR (12.72±0.37 %/day), the survival rate (83.08 ±7.58 %), and the FCR (1.62 ±0.16) among the groups. The growth performance graphs are shown in Appendix 4. 

Table 2. Growth performance and survival rate at the end of the trial 

Note: Values are shown as mean ± SD. Values with the same superscript small letter, “a” in the same row are not statistically different from each other (P>0.05). 

1.2. Feed consumption  

After 30 days of the nursery, the cumulative feed consumptions of all the groups were very similar. There was a normal trend in feed consumption throughout the trial. The cumulative feed consumption of the groups during the trial is shown in figure 1. 

1.3. Water quality 

Water quality parameters were kept in the optimal ranges during the trial. And most of the parameters were not much fluctuated. The salinity of all tanks was kept at 22 ppt whilst the temperature throughout the trial ranged from 28.0 to 30.5 °C, DO was from 6.0 to 7.9 mg/L and the pH ranged between 8.0 to 8.6. Alkalinity in all tanks was within the range of 100.0 to 160.0 ppm whereas TAN and nitrite were from 0.0 to 2.0 ppm and 0.0 to 4.0 ppm respectively. Water quality data are described in Appendix 5. 

Appendix 1: Photo illustrations of the trial shrimps 

Appendix 2: Tank system of the trial

Appendix 3: Microalgae preparation

Appendix 4: Growth performance