Optimum salinity level for the cultivation of ciliated protozoa

In the present study, protozoa was cultured in different salinity water (10%, 20% and 30%) to determine the optimum salinity level required for the culturing. We examined the densities of protozoa and the ciliates Euplotes spp. in a general culture and Euplotes encysticus Yonezawa in a separate monoculture. Various species of protozoa were observed in the culture water, with a peak density of 30,000–40,000 cells ml–1 on day 4. The density of Euplotes spp. in the culture water increased with elapsed days, peaking on day 3. One-way analysis of variance showed a significant difference in the densities on day 3, and post-hoc Tukey–Kramer test results showed that the density at 10% was significantly higher than that at 30%. The E. encysticus monoculture peaked at 5000–6000 cells ml–1, but there was no significant difference between the salinity levels. Although our results are not definitive, the lower salinity level appeared most suitable for culturing protozoa. The ciliated protozoa Euplotes spp. in the current study were smaller than 100 μm, and they may be suitable size as live feed as starter diet for marine fish larvae with small mouth openings

Larval rearing of Asian seabass using rotifer, protozoa, and Euplotes encysticus

Seed production of marine finfish in Malaysia is still facing problem particularly live feed for starter diet. Currently, aqua culturists use S or SS type rotifers, which have sizes from 100 to 200μm. Early stage larvae of some marine finfish species select feeds less than 100 μm. Protozoa is a collective term of aquatic microorganism that has been identified to be suitable live feed, as their body sizes are less than 100μm. Thus, the objective of this experiment is to compare the survival rates of Asian seabass larvae using four types of live feeds. Four types of live feed; rotifer, protozoa, E. encysticus, and mixed (rotifer, protozoa, and E. encysticus) were used in this experiment. The larvae were fed from 2 to 10 day-after-hatching. Asian seabass larvae were given the same amount of live feed in each larval rearing tank; twice a day. The feeding densities were 20 individual / mL for rotifers, protozoa, E. encysticus, and mixed group. Number of seabass larvae in each group was counted every day and their survival rates were determined. Starting from 3 DAH until 10 DAH, mixed group showed the higher survival rates than other groups. The most recommended live feed was mixed group

Optimum salinity level for the cultivation of ciliated protozoa

In the present study, protozoa was cultured in different salinity water (10%, 20% and 30%) to determine the optimum salinity level required for the culturing. We examined the densities of protozoa and the ciliates Euplotes spp. in a general culture and Euplotes encysticus Yonezawa in a separate monoculture. Various species of protozoa were observed in the culture water, with a peak density of 30,000–40,000 cells ml–1 on day 4. The density of Euplotes spp. in the culture water increased with elapsed days, peaking on day 3. One-way analysis of variance showed a significant difference in the densities on day 3, and post-hoc Tukey–Kramer test results showed that the density at 10% was significantly higher than that at 30%. The E. encysticus monoculture peaked at 5000–6000 cells ml–1, but there was no significant difference between the salinity levels. Although our results are not definitive, the lower salinity level appeared most suitable for culturing protozoa. The ciliated protozoa Euplotes spp. in the current study were smaller than 100 µm, and they may be suitable size as live feed as starter diet for marine fish larvae with small mouth openings

Starter diet for Asian seabass larvae

Seed production of marine finfish in Malaysia is still facing problem particularly live feed for starter diet. Currently, aqua culturists use S or SS type rotifers, which have sizes from 100 to 200μm. Early stage larvae of some marine finfish species select feeds less than 100 μm. Protozoa is a collective term of aquatic microorganism that has been identified to be suitable live feed, as their body sizes are less than 100μm. Thus, the objective of this experiment is to compare the survival rates of Asian seabass larvae using four types of live feeds. Four types of live feed; rotifer, protozoa, E. encysticus, and mixed (rotifer, protozoa, and E. encysticus) were used in this experiment. The larvae were fed from 2 to 10 day-after-hatching. Asian seabass larvae were given the same amount of live feed in each larval rearing tank; twice a day. The feeding densities were 20 individual / mL for rotifers, protozoa, E. encysticus, and mixed group. Number of seabass larvae in each group was counted every day and their survival rates were determined. Starting from 3 DAH until 10 DAH, mixed group showed the higher survival rates than other groups. The most recommended live feed was mixed group

Larval rearing of Asian seabass using protozoa

Seed production of marine finfish in Malaysia is still facing problem particularly live feed for starter diet. Currently, aqua culturists use S or SS type rotifers, which have sizes from 100 to 200μm. Early stage larvae of some marine finfish species select feeds less than 100 μm. Protozoa is a collective term of aquatic microorganism that has been identified to be suitable live feed, as their body sizes are less than 100μm. Thus, the objective of this experiment is to compare the survival rates of Asian seabass larvae using rotifers, protozoa, and one kind of protozoa; Euplotes encysticus. Four types of live feed; rotifer, protozoa, E. encysticus, and mixed (rotifer, protozoa, and E. encysticus) were used in this experiment. The experiment was conducted in triplicates. The larvae were fed from 2 to 10 day-after-hatching. Asian seabass larvae were given the same amount of live feed in each larval rearing tank; twice a day. The feeding densities were 20 individual / mL for rotifers, protozoa, E. encysticus, and mixed group. Number of seabass larvae in each group was counted every day and their survival rates were determined. The result from this experiment showed that the survival rates of Asian seabass on 10 day old, the mixed group was significantly higher than other groups. However on 4 day old, the highest survival rate was in E. encysticus group, followed by mixed, protozoa, and rotifer group. Based on the results, recommended live feed was mixed group which consists of rotifer, protozoa, and E. encysticus

Infusoria cultivating methods for marine finfish larvae using vegetables and dry fish powder

Seed production of marine finfish in Malaysia is still facing problem particularly live feed for starter diet. Currently, aqua culturists use S or SS type rotifers, which have sizes from 100 to 200μm. Early stage larvae of some marine finfish species select feeds less than 100 μm. Infusoria is a collective term of aquatic microorganism that has been identified to be suitable live feed, as their body sizes are less than 100μm. However, there is no data about basic culture methods. Thus, the objective of this experiment is to study the method of culturing infusoria using batch culture method and continuous culture method. In batch culture method, infusoria were cultured in triplicates for a duration of 2, 4, 6, and 8 days in 500 mL saline water respectively. In this experiment, the nutrients used were powder vegetables (Brassica pekinensis and Brassica chinensis) and powdered anchovies. The nutrients were only given at the first day of experiment. In continuous culture method, infusoria were cultured in the beakers for a duration of 11 days in triplicates. Every day, 10%, 20%, and 30% of cultured water were harvested from the beaker. After that, the same amount of saline water and nutrients were added in the beaker. For the results of batch culture method, the highest total harvested was in 4 days which was 2,690,000 ind/500 mL. Followed by, 2 days with 2,480,000 ind/500 mL, 6 days with 607,000 ind/500 mL, and 8 days with 202,000 ind/500 mL. The results for continuous culture method showed that the total harvested in 11 days were 777,250 ind in 10%, 1,123,000 ind in 20%, and 814,500 ind in 30% respectively. Based on the results, the recommended cultivation period for batch culture method was 4 days. For continuous culture method, the recommended harvesting amount per day was 20%