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The current study was carried out to compare the hydrobiological characteristics of a selected shrimp farm in district Ratnagiri taking pond size, stocking density and culture practices into consideration. For sampling, four earthen and four high-density polyethylene (HDPE) ponds were chosen. Most of the water parameters showed significant difference with respect to different types of ponds (earthen and HDPE) viz. temperature, pH, salinity, dissolved oxygen, alkalinity and net primary productivity (NPP) of both crops (p<0.05). First crop showed significant difference among all water parameters except biochemical oxygen demand (p<0.05). Second crop (January-May) showed significant difference (p<0.05) among all parameters except hardness, ammonia, nitrite, gross primary productivity (GPP) and community respiration (CR). Phytoplankton showed significant difference (p<0.05) with respect to different types of ponds for both crops and zooplankton showed significant differences (p<0.05) only during first crop. Results indicated that high-density polyethylene (HDPE) ponds have greater consistency in water quality characteristics than earthen ponds, which could contribute to enhanced shrimp growth and survival. [ABSTRACT FROM AUTHOR]

Mud crabs are common edible crustaceans, which are fished along the coasts of India. Scylla tranquebarica (Fabricius 1798), commonly called green crab is one of the most economically important portunid crab in India. The study was carried out to determine the sex ratio, maturation and spawning, gonadosomatic index, fecundity and egg diameter. Sex ratio of 1 female to 1.3 male gave good results. Size at first maturity was observed at 11 cm carapace width (CW) in males and 10 cm (CW) in females. The highest GSI values in males (6.17) and females (5.12) were observed in the month of October. The maximum number of eggs produced by the females was up to 5 million. The egg diameter was recorded in the range of 0.69 to 0.76 mm. The incubation period was 11-13 days. The hatching success average percentage was recorded as 80%. For the incubation and larval rearing of mud crab, Scylla tranquibarica, the optimum requirement of water temperature and salinity were recorded as 28°C and 30 ppt, respectively. [ABSTRACT FROM AUTHOR]

A sixty days experiment was carried out to study the effect of feeding varying dietary protein diets on hematology of catla, Gibelion catla in biofloc system. The experiment consisted of four biofloc treatments with different dietary protein, T1 (20% CP), T2 (25% CP), T3 (30% CP) and T4 (35% CP) and clear water control without biofloc T0 (30% CP) each with four replicates. Catla fry of average weight (0.21±0.01g) were stocked at the rate of 3 fry per 10 L (24 no’s fish in 80L). C:N ratio 20:1 was maintained in biofloc system. Hematological parameters were analyzed before and after fingerlings were challenged with Aeromonas hydrophila pathogen containing 1 × 107 cfu/ml. The results revealed that 30% CP diet in biofloc system can improve the hematological profile of fish compared to control. During pre- challenge study, the dietary protein diet could not produce any significant difference (P>0.05) in RBC of catla fingerling compared to control. The WBC, Hb and Hct were significantly higher in biofloc treatments than control and increased with increase in protein level from 20 to 30% CP in biofloc treatment. During post- challenge RBC, Hb, Hct reduced and WBC count increased compared to pre- challenge. T3 group showed significantly (P<0.05) higher RBC, Hb and Hct and lower WBC compared to control. The result indicated that feeding 30% CP diet to catla fry in biofloc system could enhance the health condition as well as disease resistance of the fish and the technology can be considered useful for disease prevention in rearing practices of catla. [ABSTRACT FROM AUTHOR]

Experiment was conducted to evaluate the effect of varying dietary protein levels on growth and survival of Labeo rohita fry in biofloc system. Experiment was conducted in triplicate by following CRD for 80 days. Six experimental diets were prepared viz. D1, D2, D3, D4, D5, D6 with different dietary protein levels i.e 15%, 20%, 25%, 30%, 35%, 40% respectively for biofloc system and 30% CP for clear water system as a control (D0). Initial fry length (1.90 ± 0.17 cm) and weight (0.77 ± 0.01 g) was stocked in all treatments. After 80 days significant (p < 0.05) growth parameters were recorded in terms of average weight (4.34 ± 0.11 g), weight gain (5612.7 ± 215.09%), length gain (289.43 ± 1.0%), specific growth rate (1.95 ± 0.02%) were observed in T3 25% CP as compared to other treatments in biofloc systems and clear water system. Higher survival (%) was observed in T3 (25% CP). Study concluded that, 25% CP feed can be used to rear Labeo rohita fry in biofloc system and crude protein (%) can be reduced up to 15% . Use of biofloc technology definitely assures growth and survival in rohu fry as well as to produce fingerlings size; also played role in water budgeting and eco-friendly aquaculture. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate impact of Paclobutrazol on juvenileLitopenaeus vannamei in seven replicated groups by employing CRD. The lethal toxicity of PBZ was carried out on juveniles and the 96 h, LC50 value was found to be 81.05 mgL-1. The juveniles were exposed for a period of 30 days at two different concentration of PBZ viz. 8.1 and 16.2 mg L-1 and immunological parameters were analyzed at 10 days interval. It was observed that THC and superoxide anion production significantly (P<0.05) decreased and PPO activity and clotting time significantly (P<0.05) increased in sublethal concentration as compared to control group. Present results suggest risk in Litopenaeus vannamei culture adjacent to Paclobutrazol treated areas and that PBZ affects the immune response of juveniles. [ABSTRACT FROM AUTHOR]

Experiment was conducted in triplicate groups on freshwater prawn, Macrobrachium rosenbergii juvenile (0.84±0.01g) to evaluate the effect of dietary supplementation of mannan oligosaccharide on growth and survival. The different dietary mannan oligosaccharide levels were used 0.0, 1.5, 3.0, 4.5 g kg-1 diet. After 60 days of feeding there was significant (p < 0.05) increment in terms of weight, weight gain, specific growth, survival percentage and lower FCR recorded in 1.5 g kg-1 mannan oligosaccharide supplemented group as compared to other groups. The results imply the positive effect of dietary supplementation of mannan oligosaccharide (1.5 g kg-1) in the culture of freshwater prawn, Macrobrachium rosenbergii. [ABSTRACT FROM AUTHOR]