EFFECTS OF THE BLACK SOLDIER FLY LARVAE (Hermetia illucen) AS FEED ADDITIVE ON GROWTH PERFORMANCE OF SEABASS (Lates calcarifer BLOCH, 1790)

Tu P. C. Nguyen^1,*, Ha N. Nguyen², Nhan T. Dinh¹

¹Faculty of Fisheries, Nong Lam University, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Viet Nam

²Research Institute for Biotechnology and Environment, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Viet Nam

^*Corresponding author: npctu@hcmuaf.edu.vn

The objectives of this study were to evaluate the effects of additive of black soldier fly (Hermetia illucen) larvae (BSFL) on growth performance, survival rate and feed utilization efficiency of seabass (Lates calcarifer). Seabass (average weight of 20.17 ± 0.30 g/individual) were stocked into 1.5 m^-3composite tank at density of 30 individuals per tank and reared over a 12-week period. The commercially feed formulated to contain 44% crude protein was used. Diet treatments included the addition of low levels of BSFL homogenate to the diets of seabass: without BSFL (T1), 0.5% (T2), 1% (T3) and 2% (T4). The protein digestibility of feed was evaluated by using indirect method with chromic oxide as inert marker. At the end of 12 weeks of fish feeding trial, survival rate of T2 (93.33 ± 3.34%) was highest, while T3 (81.11 ± 11.70%) was lowest. The highest final weight and specific growth rate, and the lowest feed conversion ratio were recorded in treatment T3. The result showed that the average protein digestibility ranged from 85.8 to 88.2%. The protein digestibility was lowest in T1 (85.8 ± 2.4%) and highest in T2 (88.2 ± 1.8%). But the differences of protein digestibility between treatments were not statistically significant (p>0.05).

Keywords: Black soldier fly larvae Hermetia illucen, feed additive, protein digestibility, seabass Lates calcarifer

THE CHEMICAL COMPOSITION AZOLLA PINNATA, EICHHORNIA CRASSIPES (MART.) SOLMS AND HYDRILLA VERTICILLATA FOR AQUATIC FEED

Jantarat, S. and Kraiprom, T.*

Faculty of Science and Technology Prince of Songkla University, Pattani campus, 94000, Thailand

^*Corresponding author: thaintip.k@psu.ac.th

Many water plants in Thailand had high potential for aquatic feed such as Azolla pinnata, Eichhornia crassipes (Mart.) Solms and Hydrilla verticillate. The optimum level of pH and temperature for grew of Azolla pinnata were 6.5-6.70 and 28-29 degree of celsius.  There were 12 pond which grown Azolla pinnata.    The chemical composition of dry matter, crude protein, fat, fiber and ash were range 3.45-4.12%, 20.14-23.15%, 1.45-1.50%, 17.65-17.71% and 17.75-18.00%. The Azolla pinnata had high level of protein can be used for protein source of aquatic feed. The chemical composition of dry matter, crude protein, fat, fiber and ash of Eichhornia crassipes (Mart.) Solms were range 11.12-12.00%, 12.93-13.00%, 1.00-1.02%, 22.50-23.17% and 16.38-17.54%. Moreover, the chemical composition of dry matter, crude protein, fat, fiber and ash of Hydrilla verticillate were range 6.60-7.98%, 13.69-15.00%, 0.95-0.97%, 15.00-15.60% and 37.68-38.14%. In conclusion, can be used Azolla pinnata, Eichhornia crassipes (Mart.) Solms and Hydrilla verticillate for feed aquatic.

Keywords: chemical composition, Azolla pinnata , Eichhornia crassipes (Mart.) Solms, Hydrilla verticillate

PITH OIL PALM TRUNKS AND FRESH CORN FIBER AFTER CORN MILK PROCESSING FERMENTED AS FEED AQUATIC ANIMAL

Kraiprom, T ¹  Jantarat, S ¹ and Daniel Kofi²

¹Faculty of Science and Technology Prince of Songkla University, Pattani campus, 94000, Thailand

²Company: Palmy Industrial Partnership Ltd.

^*Corresponding author: thaintip.k@psu.ac.th

The fermented of the pith that part of oil palm trunks (OPT) and fresh corn fiber (FCF) which part of corn seed after corn milk processing were high potential to animal feed source. The objective of this research was to study the chemical composition of fermented pith of OPT and fresh corn fiber after corn milk processing fermented. There were 2 experiments; Experiment 1, this research had 5 treatments and 5 replications of each treatment with Completely Randomized Design (CRD). The 5 treatments compose of the pith of OPT fermented at 30 days (T1), the pith of OPT fermented with 1% of dried yeast at 30 days (T2), the pith of OPT fermented with 2% of dried yeast at 30 days (T3), the pith of OPT fermented with 3% of dried yeast at 30 days (T4); the pith of OPT fermented with 4% of dried yeast at 30 days (T5). The results showed that fat content of T1 (6.60%) was significantly higher than T4, T3, T5 and T2 (5.39, 5.07, 4.84 and 4.37%), respectively (P<0.05). The crude protein in T5 (16.56%) was significantly higher than T4, T3, T2 and T1 (15.77, 13.83, 13.26 and 12.37%), respectively (P<0.05). Experiment 2, this research had 3 treatments and 5 replications of each treatment with Completely Randomized Design (CRD). The 3 treatments compose of FCF fermented at 30 days (T1), FCF fermented with molasses at 30 days (T2) and FCF fermented with saccharomyces cerevisiae yeast 1% (T3). The dried yeast composed of 98.85% of Saccharomyces cerevisiae. The results showed that the fat (6.07-7.51%), protein (23.18-25.73%) and fiber (8.17-9.06%) content were not significant among treatment. In conclusion can be use Oil Palm Trunks and fresh corn fiber after corn milk processing fermented as protein and energy source for feeding.

Keywords: chemical composition, pith of Oil Palm Trunks, fresh corn fiber after corn milk

EFFECT OF WATER PARAMETERS ON THE CONDITION INDEX REVEALED MEAT QUALITY OF SLIPPER SHAPED OYSTERS (Magallana bileanata) FROM VISAYAS, PHILIPPINES

Ma. Ramela Angela Bermeo*¹, Elfred Abacan², Junfel Sotelo¹, and Philip Ian Padilla¹

¹Division of Biological Sciences

²Division of Physical Science and Mathematics

College of Arts and Sciences, University of the Philippines Visayas

*Corresponding author: mcbermeo@up.edu.ph

The condition index (CI) is a rapid tool that measures the ecophysicological effects from various environmental factors on oyster meat quality. This study is the first documented investigation that determines the effects of physico-chemical water parameters on the CI as a measure of meat quality of slipper-shaped oyster Magallana bileanata in Visayas, Philippines. The CI measured using protocol of Mercado-Silva (2005) and physico-chemical water parameters including temperature, salinity, pH and dissolved oxygen were collected from twelve culture sites in Visayas, Philippines for two consecutive years. The study showed that the significant differences in CI values correspond to the effects of the different sites as revealed by the Welch’s ANOVA through Post Hoc Test comparisons. The effects of the physico-chemical water parameters on the CIs of oysters and their association with the culture site differences were determined through the Pearson’s correlation. It was found that there is a positive low correlation between temperature-CI1 (r=0.310, p<0.001), and salinity-CI1 (r=0.310, p<0.001). It implies that as the temperature or salinity increases, the CI1 value also increases. A negative negligible correlation between dissolved oxygen and CI1 was also identified. Same as in CI1, there is a positive low correlation between temperature-CI2 (r=0.320,p<0.001), and salinity-CI2 (r=0.307, p<0.001). While temperature-CI3 have a low positive correlation (r=0.271, p<0.001) and the rest of the correlation is negligible. This study reflects on the relationship of water temperature and salinity in CI variations which are critical for the quality of oyster meat. Ultimately, the results of this study could be used as baseline data in further developing large-scale culture technologies to better marketable oyster meat production while considering the influence of environmental conditions.

Keywords: Meat quality, Condition index, Physico-chemical water parameters, Magallana bileanata, Welch’s ANOVA

THE EFFECT OF DIFFERENT CULTURE MEDIA ON THE GROWTH AND NUTRIENT CONTENTS OF MAGGOT (Hermetia illucens L.) AS FISH FEED INGREDIENT

Agung Nugroho, Senny Helmiati^*

Aquaculture Study Program, Department of Fisheries, Faculty of Agriculture, Universitas Gadjah Mada, Flora Street Bulaksumur, Yogyakarta, Indonesia

^*Corresponding author: senny@ugm.ac.id

Feed is one of the biggest cost elements in the aquaculture business. Maggot (Hermetia illucens L.) is one of the potential alternative feeds to overcome the high price of feed. Local organic waste as its alternative culture media should be evaluated. This study was conducted to determine the growth rate and nutrient content of maggot cultured in different media. This research was conducted in the Girikerto Fish Farming Group, Turi, Sleman, Yogyakarta, Indonesia. The study used The Completely Randomized Design method with palm kernel meal, coffee skin waste, P3 bread waste, and restaurant waste fermentation in triplicates. One gram of maggot egg was reared in each experimental unit. Sampling was conducted 0, 5, 10 and 15 days after rearing. The parameters discussed in this study are the nutrient content of culture media and maggot, growth, and biomass of maggot. The data were analyzed using analysis of variant with α=5% followed by The Duncan Multiple Range Test. Bread waste produces the highest nutrient content, namely protein 22.03±0.04%, fat 22.75±0.19%, crude fiber 20.93±0.045%, ash 3.99±0.2%, and carbohydrates of 30.64±0.81%. Maggots cultured in bread waste contain protein 68.48±0.05%, fat 31.08±1.26%, crude fiber 1.33±0.02%, ash 15.43±0.45%, and carbohydrates of 4.07±0.63%, and show the best growth performance with an absolute growth in weight value of 6.70±0.566 g, an absolute growth in length of 1.34±0.025 cm, the specific growth rate in weight of 0.45±0.038%/day, the specific growth rate in length 0.09±0.002%/day, and biomass of 1255.27±55.813 g. So, it concluded that bread waste might be used as a growth medium in maggot culture.

Keywords: Fish feed ingredient, Local organic waste, Maggot, Nutrient content, Growth performance

CYST BIOMETRY, GROWTH PERFORMANCE AND REPRODUCTIVE CHARACTERISTICS OF ARTEMIA STRAINS FROM DIFFERENT GEOGRAPHICALLY REGIONS

Nguyen Thi Hong Van^1*, Phan Thi Nhu Y² and Nguyen Van Hoa¹

¹College of Aquaculture and Fishery, Cantho University

²Graduated student in Aquaculture (K44)

^*Corresponding author: nthvan@ctu.edu.vn

In this study, the cysts of seven Artemia strains that were collected from different geographical locations; were used for cysts biometric assessment as well as to identify Artemia performance and some of their reproductive characteristics under laboratory condition. The results showed that there were statistical differences on cyst biometry, growth and reproductive characteristics between strains (p<0.05).The biggest cyst size was found with GSL (262.0±25.4mm) while the smallest was SFB (212.7±16.9mm), the remaining strains were negligible difference. The thickest cyst shell thickness was GSL with 11.8±5.1mm, thinnest one was the UZB strain   with 2.1±5.5mm. The embryo size is quite small, ranging from 197.2-251mm. The Nauplii size was largest in the GSL (525.4±48.5mm) and the smallest was CHINA with 430.7±35.1mm.The specific growth rates of Artemia stages in their lifetime (correspoding with 3,5,8 and 14 day olds) was statistically significant difference (p<0.05)and relating to their original strain in which 6 were bisexual population and one was parthenogenetic population (UZB). Average fecundities ranged from 33.9 to 54.6 embryos/female and there was no different in reproductive pattern between strains. Strain Biometric and reproductive characteristics seemed to related to genetic inheritance and their living habitats at different geographical regions.

Keywords: Artemia,strain, biometry, origin.

COMBINED EFFECT OF STOCKING DENSITIES AND FEEDING RATION ON PERFORMANCE AND SURVIVAL RATES OF JUVENILE RICE-PADDY EELS (Monopterus albus)

Tran Nguyen Hai Nam^2*, Huynh Thanh Toi¹ and Nguyen Thi Hong Van¹

¹College of Aquaculture and Fishery, Cantho University

²College of Rural developmment, Cantho University

*Corresponding author: tnhnam@ctu.edu.vn

In this study, the combined effect of stocking densities and feeding ration to growth and survival rate of rice-paddy eels (Monopterus albus) at juvenile phase was designed with two-factorial experiment including stocking densities (1350, 2000 và 2700 individual/m²) and feeding ration (twice and four times a day). The combination of these two factors produced 6 treatments with 3 replicates for each, and nursing period lasted for 40 days. Eels were nursed in 18 plastic basins with nilon substrate and water level was kept less than 10 cm, frozen Artemia biomass was used as food during experiment. With initial weight of 0.173g/ind. and 5cm in length, after 40 days all treatments were reached 100% in survival. The growth in term of final length and weight, DLG (Daily Length Gain), DWG (Daily Weight Gain and SGR (Specific Growth rate) was highest in treatment 4 (stocking density at 1350 eels/m² and feeding ration at 4 times a day; 3.25 g and 15.4 cm; 0.26±0.00 cm/day and 0.08±0.002 g/day; 7.33±0.01 %/day respectively) and significant difference (p<0.05) with treatment 3 (stocking density at 2700 eels/m², feeding ration twice a day; 2.60 g and 14.2 cm; 0.23±0.00 cm/day; 0.06±0.00 g/day; 6.78±0.34 %/day respectively), but no significant difference (p>0.05) with other remain treatments. These results indicated that nursing density from 1350-2000 ind./m² juvenile eels was suitable when Artemia biomass was used as food, however if nursing at about 2000 ind./m², feeding four times a day will enhance the best growth.

Key words: rice eel, density, feeding ration, Growth, survival

EFFECT OF ACID SULFATE WATER AND SALINITY ON PHYSIOLOGICAL PARAMETERS OF STRIPED CATFISH (Pangasianodon hypophthalmus) FINGERLING

Ha T.K. Nguyen^1*, Ai D. Nguyen¹, Thuan H. Le¹, Huong T.T Do¹, Phuong, T. Nguyen¹

 Can Tho University, Campus 2, 3/2 Street, Can Tho City, Viet Nam

^*Corresponding author: kimha@ctu.edu.vn

The study was carried out to evaluate the effects of acid sulfate water at different pH levels in combination with salinity on some physiological parameters of catfish (Pangasianodon hypophthalmus) fingerling. Fish were randomly arranged into 6 treatments including 3 pH levels (5.5; 6.5 and 7.5) combined with 2 salinity levels (3‰ and 6‰). The results showed that after 14 days of the experiment there was no interaction between pH and salinity on physiological parameters of fish. However, regarding to the effect of pH, red blood cell (RBC), hemoglobin (Hb), and hematocrit at pH 5.5 were higher than those at pH 7.5, but the difference was only shown at 6h and day 1 in the number of RBC and day 14 in Hb and Hct (p<0.05). On the other hand, the number of RBC at 6‰ was lower than those in 3‰ treatment with the difference being statistically significant at 6 hours, day 1 and day 7. Glucose concentration, osmolality and Na⁺ ion concentration were not affected by different pH conditions; Cl^- ion concentration at pH 5.5 was significantly reduced compared to pH 6.5 after day 1 of exposure. Osmolality, glucose, Na⁺ ion concentrations in the 6‰ group were higher than that in the 3‰ group after 14 days of culture, but only significant differences at day 3 for glucose, 6 hours for osmolality and day 14 for Na⁺ ion (p <0.05). In general, acid sulfate water at pH 5.5 and salinity 6‰ may affect on the physiological parameters of striped catfish.

Keywords: Acid sulfate water, physiological parameters, Pangasianodon hypophthalmus, pH, salinity

EFFECT OF REPLACEMENT OF FISHMEAL-BASED DIET BY FULL-FAT OR DEFATTED BLACK SOLDIER FLY LARVAE (Hermetia illucens) MEAL IN DIETS ON PERFORMANCE OF ASIAN SEABASS (Lates calcarifer) JUVENILE IN FRESH AND BRACKISH WATER

Lan P. T. Pham¹_,  Ngoan D. Le², Tram Q. D. Nguyen¹*

¹Faculty of Fisheries, Hue University of Agriculture and Forestry, Hue University, Vietnam 
²Faculty of Animal Science, Hue University of Agriculture and Forestry, Hue University, Vietnam

*Corresponding author: ndqtram@hueuni.edu.vn 

This study aimed to examine the growth performance of seabass juvenile (Lates calcarifer) fed full-fat or defatted black soldier fly larvae (BSFL) meal replacing fishmeal-based diets. A total of 480 seabass juvenile of 14.5 g were randomly allocated into 2 x 3 factorial design treatments (water sources: fresh and brackish water; and feed types: fishmeal, FM, full-fat, FF and defatted BSFL meal, DF). Fish were kept in a 160 L aquarium, with density of 125 fish/m³. The results showed that, with exception of the survival rates, final weight, SGR_w and yield were effected by water sources, feed types and their interaction (P<0.05), and final length, SGR_L and FCR were effected by feed type (P<0.05) but not water sources (P>0.05). In conclusion, replacing 30% fishmeal-based diet by full-fat BSFL meal improved growth performance of seabass juvenile.

Keywords: Feed type, larval meal, seabass juvenile, water source

Authors: Loi T. Nguyen*, Ha K.T. Nguyen, Ha T. Tran, Huong T.T. Do and Phuong T. Nguyen

STUDY OF EFFECTS OF LIGHT INTENSITY ON SURVIVAL RATES AND GROWTH RATES OF SCALY GIANT CLAMS’ LARVAE AT SPAT STAGE

Bay Phung¹, Nga Nu My Ton², Trang Thi Thuy Nguyen², Hue Thi Nguyet Nguyen³,

Lam Son Ho³

¹Research Institute for Aquaculture No.3, Nha Trang, Vietnam

²Institute of Aquaculture, Nha Trang University, Nha Trang, Vietnam

³Institute of Oceanography, Vietnam Academy of Science and Technology, Nha Trang, Vietnam

^*Corresponding author: ngatnm@ntu.edu.vn

A 26- day experiment has been conducted to find out the most suitable light intensity for scaly giant clams Tridacna squamosa‘s larvae from pediveliger stage to spat stage. The experiment was replicated four times with four different light intensity treatments (2000 lux, 4000 lux, 6000 lux, 8000 lux) in 1 m³ tanks, at salinity of 30‰. Larval density was 5 individuals/ml. Feeds were single-celled algae such as Isochrysis galbana, Chaetoceros sp and symbionts at the densities from 6,000 to 9,000 cells/ml. The results showed that in 4 above light intensities, the 4000 lux light intensity gave the highest growth in height, absolute growth rate  in heith and survival rate. The larvae’s average height after 26 days cultured was 1032.1 µm, the growth rate in the height was 30.8 μm/day and survival rate was 42.8%.

Key words: Growth, Scaly giant clams, Survival rate, Tridacna squamosa

EFFECTS OF DIETARY TUNA VISCERA HYDROLYSATE SUPPLEMENTATION ON GROWTH AND INTESTINAL MUCOSAL RESPONSE IN POMPANO (Trachinotus blochii)

Hung Duc Pham^1*, Muhammad A.B. Siddik², Hoang Minh Le¹, Manh Van Ngo¹ , Minh Van Nguyen¹, David Francis³

¹Nha Trang University, Nha Trang, Khanh Hoa, Vietnam.

²Patuakhali Science and Technology University, Patuakhali 8602, Bangladesh

³Deakin University, Geelong, VIC 3216, Australia

^*Corresponding author: hungpd@ntu.edu.vn

The effects of tuna viscera hydrolysate (TVH) on juvenile pompano Trachinotus blochii, growth performance, nutritional response, intestinal and liver health were investigated in this study. Five isonitrogenous and isocaloric diets (protein 46.0%, lipid 10.0%) were formulated in which TVH were added to replace fishmeal protein at levels of 0 (control), 30, 60, 90 and 120 g kg^-1, labelled as TVH0, TVH05, TVH10, TVH15 and TVH20, respectively. Triplicate groups of pompano were fed the respective diets for ten weeks. The results showed that fish fed diets containing TVH10 produced significantly higher final body weight and specific growth rate in comparison to the fishmeal control (P < 0.05). Dietary TVH did not produce any effect on feed utilisation, somatic indices and proximate composition of juvenile pompano (P > 0.05). Whilst most amino acids were unchanged by the dietary inclusion of TVH, phenylalanine and valine levels were significantly lower in the fish fed TVH20 diet compared to the control. Fish fed the TVH20 diet had significantly lowered total serum protein compared to the TVH10 treatment, whereas other biochemical parameters in the blood did not show any difference among treatments. The intestinal histology indicated a significant increase in goblet cell numbers in fish fed TVH10 diet. Based on a quadratic regression between final body weight and dietary TVH levels, the optimum TVH was calculated to be 10% or 60.0 g kg^-1 for maximum growth performance when fed to pompano.

Keywords: Protein hydrolysate, pompano, fatty acid, amino acid, gut morphology.

SALINITY STRESS TOLERANCE OF Eucheuma denticulatum FROM TISSUE CULTURE USING ACADIAN MARINE PLANT EXTRACT POWDER (AMPEP)

Hazel Coleen Gaya^1*, Iris Ann Borlongan¹

¹Institute of Aquaculture, College of Fisheries and Ocean Sciences, University of the Philippines Visayas, 5023 Miagao, Iloilo, Philippines

*Corresponding author: hggaya@up.edu.ph

Climate change negatively affects the ocean and everything in it including the economically important carrageenophytes, causing salinity fluctuations that have adverse effects on seaweed farming. Seaweed production in the Philippines continues to decline, mainly due to loss of strain vigor and increased incidences of pests and diseases brought about by repeated vegetative propagation from a limited genetic stock. The use of Acadian Marine Plant Extract Powder (AMPEP) in in vitro tissue culture of seaweeds has been revealed as an effective biostimulant for mass production of seedlings, further providing levels of protection against biotic and abiotic stresses. The present study aimed to determine the response of Eucheuma denticulatum produced from tissue culture using AMPEP to salinity variations. Micropropagules of E. denticulatum (90-day post-tissue culture) were further cultured for 45 days in UV-filtered natural seawater at different salinities (15, 20, 25, 30, 35, 40, and 45 PSU), with renewal of respective seawater treatments every 7 days. Percent survival of E. denticulatum micropropagules at 20–45 PSU showed no significant difference with relatively high values (96.25 ± 2.39% at 20 PSU to 100 ± 0.00% at 45 PSU, mean ± SEM). Micropropagules at 15 PSU showed signs of thallus whitening as early as Day 28, and eventually disintegrated. Specific growth rates of E. denticulatum at 20 (1.37 ± 0.07% day^-1) and 25 PSU (1.52 ± 0.09% day^-1) were comparable to those exposed to natural seawater salinities (1.58 ± 0.04% day^-1 at 30 PSU and  1.38 ± 0.05% day^-1 at 35 PSU); whereas values significantly decreased at hypersaline conditions (1.12 ± 0.11% day^-1 at 40 PSU and  0.52 ± 0.07% day^-1 at 45 PSU). High chlorophyll-a content was observed on micropropagules in hypersaline conditions (0.007–0.011 mg mL^-1). These results suggest that while E. denticulatum from tissue culture using AMPEP had a wide range of salinity tolerance from 20 to 45 PSU, its growth was reduced with increased chlorophyll-a content in hypersaline conditions.

Keywords: Salinity tolerance, Eucheuma denticulatum, tissue culture, AMPEP, biostimulant

ISOLATION, IDENTIFICATION, AND POTENTIAL PROBIOTIC CHARACTERIZATION OF LACTIC ACID BACTERIA ISOLATED FROM INTESTINAL TRACTS OF MARINE FISH

Rohaya Salah, Supinya Thapthong, Pochanart Kanjan

Department of Agricultural and Fishery Science, Faculty of Science and Technology, Prince of Songkla University, Pattani 94000, Thailand

*Corresponding author: pochanart.k@psu.ac.th

This study involved isolation of lactic acid bacteria (LAB) from intestinal tracts of marine fish and characterization of their physiological and probiotic properties based on antibacterial activity against pathogenic bacteria, salt tolerance, and antibiotic susceptibility. A total of 38 presumptive LAB colonies that appeared as Gram-positive and catalasenegative were collected. Only 5 isolates designated LAB 1, LAB 3, LAB 11, LAB 29 and LAB 37 exhibited an excellent inhibitory zone diameter against aquatic pathogenic bacteria when evaluated by agar spot test. Lactic acid bacterial isolates with antibacterial activity showed strong salt tolerance which survival rates more than 90% and presented no significant concerns with regards to antibiotic resistance. Among these, isolate LAB 29 showing the highest antibacterial activity against all pathogenic bacteria was identified as Lactobacillus plantarum based on 16S rRNA sequence analysis. This research suggests that selected LAB could be used as a food/feed supplement to reduce pathogenic bacteria in food or aquatic animal.

Keywords: Lactic acid bacteria; marine fish; pathogenic bacteria; probiotic

GROWTH PERFORMANCE OF NILE TILAPIA FED WITH DIFFERENT LEVELS OF IPIL-IPIL (Leucaena leucocephala) LEAF MEAL SUPPLEMENTED DIET

Shailesh Gurung¹*, Juli-Anne Royes Russo², Nabin Chalaune¹, Ashish Chaudhary³, Subodh Raj Bhattarai⁴, Suraj Kumar Singh⁵

¹Department of Aquaculture, Tribhuvan University/IAAS, Kirtipur, Nepal

²Aquatic Animal Scientist, Caribbean Aquaculture Network, Italy

³Department of Aquaculture and Fisheries, University of Arkansas at Pine Bluff, USA

⁴College of Aquaculture and Fisheries, Can Tho University, Vietnam

⁵Directorate of Agricultural Research, Nepal Agriculture Research Council, Sunsari, Nepal

*Corresponding Author: gurungshailesh@gmail.com

The dietary effects of a leucaena leaf meal (Leucaena leucocephala) supplemented diet on the growth performance of Nile tilapia were determined for 90 days, from January 2021 to April 2021 in IAAS, Bhairahawa, Nepal. Fifteen indoor glass aquaria 2x1x1 ft³ with a 45-liter water capacity was set up with 5 treatments and 3 replications. Fingerlings in each aquarium were stocked at a mean weight of 4.5g at 10 fish m^-3. Regular water exchange and removal of wastes and feed residue was done periodically.The pelleted basal diet with 30% crude protein was prepared with soybean meal, mustard oil cake, rice bran, wheat flour and vitamin premix in 28g, 28g, 22g, 21g and 1g/100g of feed respectively. The treatments were, (a) T₁(control) with no LLM, (b) T₂-10%replacement of soybean meal with LLM, (c) T₃- 20% replacement of soybean meal with LLM, (d) T₄-30% replacement of soybean meal with LLM and (e) T₅- 40% replacement of soybean meal with LLM. T₂ was found to be significantly different (P<0.05) from other treatments having a maximum weight of 152.48g at the end of the experiment with the lowest weight inT₅(129.14g). Similarly, T₂was also significantly higher (P<0.05) in average daily weight gain (0.116g), followed by T₃ (0.110g), T₁(0.100g), T₄(0.09g) and T₅(0.09g) at (P<0.05).Furthermore, T₂ showed the highest Specific growth rate (SGR) with 1.30 followed by T₃(1.22), T₁(1.19),T₄(1.11) and T₅(1.10) respectively at (P<0.05). Average temperature, dissolved oxygen, pH, ammonia ranged from15-17^oC, 5.7-7.3mg/L,8.5-8.9,<1 mg/Lrespectively among the treatments during the experimental period. The present study shows that T₂ with 10%replacement of Soybean meal with LLM has better growth performances than other treatments.

Keywords: Fingerlings,Aquaria, Leucaena leucocephalaMeal (LLM),Daily weight gain, Specific growth rate,

EFFECT OF THE FREQUENCY ADDING SUGAR FOR THE NURSING GIANT FRESHWATER PRAWN (Macrobrachium rosenbergii) LARVAE APPLYING BIOFLOC TECHNOLOGY

Pham Minh Truyen^*, Chau Tai Tao, Tran Ngoc Hai

Can Tho University, Campus 2, 3/2 Street, Can Tho City, Viet Nam

^*Corresponding author: phamminhtruyen1979@gmail.com

The study aimed to find the suitable frequency of sugar supplements on growth, survival, and yield of giant freshwater prawns of larvae and postlarvae applied biofloc technology. The experiment included 5 treatments with different supplemental sugar cycles: (i) one time a day; (ii) two times per day; (iii) three times per day; (iv) four - times per day; (v) five - times per day, each treatment was triplicated, stocking density was 60 ind/liter and water salinity was 12‰, the experimental tank was 0.5 m³ in volume, sugar was applied to create biofloc from stage 4, with the ratio of C/N = 17.5/1. The results showed that the length of the PL15 (10.35 ± 0.03 mm) in the treatment supplemented with sugar one time a day difference was statistically significant (p < 0.05) compared with the other treatments. The survival rate (48.2 ± 0.81%) and yield (28,888 ± 485 ind/m³) of PL15 in the treatment of adding sugar one time a day were not statistically significant (p > 0.05) compared with the treatment of adding sugar two times per day, but the difference was statistically significant (p < 0.05) compared to the other treatments. It can be concluded that rearing giant freshwater prawn larvae using biofloc technology supplemented with sugar one time a day is best.

Keywords: Giant freshwater prawn, larvae, biofloc