Evaluation of claw development in giant freshwater prawn, Macrobrachium rosenbergii (de Man, 1879)

Dynamics of claw development in Macrobrachium rosenbergii (de Man, 1879) was evaluated through monosex culture. The segregated males and females were stocked separately in two earthen ponds of 200 m2 area, at a density of 2.5 m-2 and reared for 3 months. Percentage contribution of claw weight to body weight (PCB) increased from 8.96 to 14.4% in the first month, but the change was minimal (14.4 to 17.19%) during the rest of the culture period. In order to delineate the relationship further, the data obtained was pooled together and classified into different classes based on the body weight (class interval 10 g). Interestingly, PCB in males decreased gradually upto 30 - 40 g weight class and then increased considerably for higher weight classes. But for females, the increase in PCB was marginal

Ontogenetic Development of Digestive Tract and Enzymes Activity in Hatchery-reared Pink Ear Emperor, Lethrinus lentjan Larvae

Ontogenetic development of the digestive tract and associated organs of Lethrinus lentjan larvae was were learned by observing changes in external morphology, histology, and enzymatic changes from hatchling to 40-day post-hatching (dph). Ontogenetic development of the L. lentjan digestive system can be divided into three major stages; the first stage from hatching of larvae to complete absorption of yolksac, which ends on 2 dph, the second stage from 3 to 15 dph i.e., from exogenous feeding to the formation of the gastric gland and third stage till completion of metamorphosis (35 dph). Pyloric caeca were developed after 20 dph, which was formed entirely by 27 dph. Enzymatic activities of amylase, lipase, trypsin and chymotrypsin were detected before the onset of exogenous feeding and pepsin was detected from 19 dph onwards in L. lentjan. So considering both histology of digestive tract and enzyme development, weaning of L. lentjan larvae to artificial diet can be practiced after 19-20 dph coinciding with the formation of pyloric caeca and production of pepsin enzyme for better digestibility and consequently better growth and survival. The present study can be expended as a reference guide to understand the digestive tract development and successful hatchery rearing of other economically important marine fishe

Observations on impact of stunting on breeding performance of farmed rohu Labeo rohita (Hamilton, 1822)

Breeding performance of stunted rohu Labeo rohita (Hamilton, 1822) was compared with normally reared rohu. Randomly selected stunted and normal fishes were tagged and reared together in a single earthen pond for broodstock development. Both groups exhibited growth enhancement during the broodstock development period, though normal fishes were found larger in size than the stunted fishes, after the rearing period. Gonadosomatic Index (GSI) of female fishes indicated a similar trend of ovary growth in both the group

Effect of dietary tryptophan supplementation on growth, body composition and digestive enzymes activity of juvenile silver pompano Trachinotus blochii (Lacepede, 1801)

A 60-day feeding trial was conducted to study the effect of dietary supplementation of tryptophan in juvenile silver pompano Trachinotus blochii (Lacepede, 1801) (Average initial weight=6.81±0.05 g). Five isonitrogenous and isolipidic feeds supplemented with tryptophan at different levels, 0 (TRP0), 0.5 (TRP0.5), 1.0 (TRP1.0), 1.5 (TRP1.5) and 2.0 (TRP2.0) g 100 g-1 of diets were formulated. The weight gain%, specific growth rate, hepato-somatic index, digestives enzymes of stomach and intestine except protease activity in stomach, red blood cells, white blood cells, crude protein, fat and ash content of the fish were significantly influenced (p<0.05) by tryptophan supplementation. The viscero-somatic index, intraperitoneal fat ratio, muscle ratio, protease activity in the stomach and acid insoluble ash were unaffected by the treatment. Best observations in terms of growth, body composition and digestive enzyme activity among the treatments were obtained in the fish group fed with tryptophan at a level of 0.5 g 100 g-1 feed. From the current observations it can be concluded that supplementation of tryptophan at the rate of 0.5 g 100 g-1 diet can positively influence the growth of T. blochii

Not Available

Not AvailableGrowth, body composition and antioxidant status of Litopenaeus vannamei under zero water exchange biofloc- based culture system using inland saline groundwater (ISGW) were evaluated during the 60-day culture period in four varying stocking densities of 60 (T1), 100 (T2), 140 (T3) and 180 (T4) juvenile shrimps m−3. The carbon : nitrogen ratio was maintained at 15:1 using sugarcane molasses. Shrimp in the BFT treatments performed significantly better (P < 0.05) than control in terms of survival (98%-100%), weight gain (10.83 to 7.68g), feed conversion ratio (1.19 to 1.30) and feed efficiency ratio (0.88–0.84) at the end of the experimental period. Higher level of crude protein (29.1% to 33.0%), lipid (5.0% to 5.6%) and ash (1.4% to 1.6%) content was observed in the tissues of the shrimps from the BFT treatments when compared to control. Antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in gills, hepatopancreas and muscle were higher in the BFT treatments than in the control. These results indicate that microbial protein from recycled waste functions as nutrient, growth promoter and antioxidant capacity stimulator in shrimp reared in BFT using ISGW.Not Availabl

Not Available

Not AvailableA study evaluating water quality and nutrient dynamics in inland saline water was carried out using biofloc technology with different C/N ratios employed to raise Litopenaeus vannamei juveniles. The study was carried out for 60 days in FRP with no water exchange. Salinity, temperature, Dissolved oxygen, pH, nutrients, Biofloc Volume and Total Suspended Solids were monitored. All biofloc units indicated reduction in alkalinity at 40th day except the treatment with highest (25:1) C/N ratio, pH and alkalinity was not significant different among various treatments. Dissolved Oxygen was found to be significantly decreasing with increasing C/N ratios. The least Dissolved Oxygen was recorded at higher C/N ratios of 20:1 and 25:1 at the end of experiment. The Total Ammonical Nitrogen (TAN) and NO2 –Nin C/N ratios 15:1 and 20:1 were found to have a significantly decreasing in trend after 20th and 18th day respectively. The NO3 –N, PO4 3-–P, BVF and TSS in biofloc were shown an increasing trend in all the experiments. The present study elucidates the suitability of optimum C/N ratios in biofloc for maintaining the water quality to raise L. vannamei in inland ground saline water. The finding could help in reducing the environmental concern saline waste water discharge from the shrimp pond to the land.Not Availabl

Not Available

We wish to acknowledgement our sincere gratitude to the Indian Council of agricultural Research (ICAR) and The Director, Central Institute of Fisheries Education, Mumbai, India for granting institutional fellowship for the successful completion of this piece of research work. We also acknowledge the facilities provided at Wet laboratory (Aquaculture), Fish Genetics and Biotechnology Laboratory of CIFE, Mumbai to carry out this research work successfully.The isolation of ten different cyanobacteria were carried out from northern parts of India and among them the cyanobacterium with maximum specific growth rate (0.246 day( - 1)) was selected for the present study. The strain was further identified using morphometric and molecular analysis using 16S rDNA sequencing and was found to be related with Leptolyngbya sp. (GenBank accession no.: KF953500). The analysis of biomass composition showed ash content, amount of carbohydrate, lipid content, amount of protein, and moisture were found to be 6.8, 27.20, 18.30, 45.70, and 2% respectively. Over 26.6% increment in lipid content was evidenced when the strain was grown in BG11 medium augmented with salinity (25 mM sodium chloride) as compared to BG11 medium without sodium chloride. The unsaturated fatty acids was found 1.39 times higher than saturated fatty acids in KF953500. The lipid separated from cyanobacteria showed saponification value of 220.28, iodine value of 84.08, cetane number of 52.16, degree of unsaturation of 84.04 (%), long - chain saturation factor of 3.09 (%) and cold - filter plugging point of - 6.76 degrees C which are generally in covenant with international standards of biodiesel. Other biodiesel properties such as pour point, flash point, acid number, viscosity, specific gravity, and density were found to be - 18 degrees C, 126 degrees C, 0.34 mg KOH/g, 4.08 mm(2) s( - 1), 0.812, and 854 kg m( - 3) respectively which falls within the acceptable ranges as per ASTM D6751 and EN 14214 standards, signifying the aptness of the microalga as promising sustainable feedstock for biodiesel.Indian Council of agricultural ResearchCentral Institute of Fisheries Educatio

Not Available

Not AvailableNot AvailableNot Availabl

Effect of stocking density and algal concentration on production parameters of calanoid copepod Acartia bilobata

The present study investigated the effect of initial adult stocking densities and algal concentrations on production parameters of calanoid copepod, Acartia bilobata. Experiments were in triplicate with seven initial stocking densities (125, 250, 500, 1000, 2000, 4000, and 8000 adult copepods L−1) fed at three different concentrations (0.5, 1 and 5 ×105 cells mL−1) of Isochrysis galbana. Various production parameters; egg and nauplii production, egg hatching success, adult survival, and sex ratio were estimated. Individual egg production (IEP) increased from day one to five in all the groups irrespective of stocking densities and algal concentrations. IEP decreased significantly (p < 0.05) on day 1 from 9.61 ± 0.79–0.17 ± 0.05 eggs female−1day−1, and on day 5 from 13.44 ± 2.94–2.99 ± 0.58 eggs female−1day−1 with increase in stocking density from 125 to 8000 adult copepods L−1 respectively; however, an increase was noted as algal concentration increased. Total accumulated egg production increased upto the density of 1000 adults L−1, with 33945.02 ± 1556.43 eggs L−1 at highest algal concentration, and thereafter declined at higher densities. Synergistic effect of stocking density and algal concentration significantly impacted 16 and 24 h hatching success. Copepod adult survival decreased significantly from 71% to 78% (125 adult copepods L−1) to 2–10% (8000 adult copepods L−1) with increase in stocking density. It is concluded that moderate stocking density of 1000 adults L−1 with highest algal concentration (5 × 105 cells mL−1) is optimum for higher reproductive performance (egg production and hatching success) of A. bilobata. Present study provides baseline information for A. bilobata commercial mass production for use in hatcheries