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Asian green mussel is commercially farmed in tidal waters in several enclosed bays in Sabah, Malaysia. In this study, two areas on the west coast of Sabah - Ambong Bay and Marudu Bay - were selected for the monitoring of the growth and mortality rates of green mussels farmed in suspension raft. Both growth and survival rates were then correlated with physicochemical parameters (dissolved oxygen, pH, salinity, temperature, water transparency, chlorophyll-a), nutrients (phosphate (PO4 3-), ammonia (NH3-N), nitrate (NO3-N) and nitrite (NO2-N) and condition index of mussel from each study site, as well as between the study sites. The twelve-month growth study (September 2017 to August 2018) was started with a total of 180 mussel specimens (90 at each site). The initial size (mean) of the mussel seed used was 47.7 ± 3.5 mm and 51.1 ± 3.9 mm for Marudu Bay and Ambong Bay, respectively. Mussels in Marudu Bay attained mean size of 73.47 ± 11.05 mm (SGR 0.17% ± 0.22) compared to 64.05 ± 7.44 mm (SGR 0.11% ± 0.22) for Ambong Bay at the end of the experiment. The cumulative mortality rates were 9.2% ± 4.9 and 55.5% ± 30.0 for Marudu Bay and Ambong Bay, respectively. The Pearson correlation indicated a significant positive relationship between mortality and water transparency (r = 0.684, p<0.01). There was a significant negative relationship between ammonia in seawater and mussel mortality (r = -0.561, p<0.01), as well as significant negative relationships between nitrate and growth (r = -0.480, p<0.05) and mortality (r = -0.460, p<0.05), as indicated by Spearman's Rank-order Correlation analysis. Overall, the growth performance of green mussels farmed in Marudu Bay was better than in Ambong Bay, however, the mortality of mussels in Ambong Bay was higher. [ABSTRACT FROM AUTHOR]

The capability of a low-cost probiotic product was evaluated in Penaeus monodon reared under an outdoor culture system for a period of 90 days. The low-cost probiotic product was formulated by mixing the broth culture of Bacillus cereus along with commercial chalk powder in 1:1 ratio. The prepared probiotic product as a powdered supplement was incorporated along with the shrimp diet at various concentrations (1 to 5%). The viability of B. cereus in the experimental diet was tested once in 30 days up to 90 days during the experimentation. After 90 days of feeding experiments, the growth performance of shrimp was determined with a maximum production of 11.98 ± 0.367 g, SGR of 5.030 ± 0.171% and FCE of 86.63 ± 1.300% in P. monodon fed D4 diet (4% probiotic supplement). The immunological parameters determined at the end of the culture experiment showed variation among diets. The total haemocyte count (273.66 ± 3.09 × 105 cells/ml), phenoloxidase activity (0.132 ± 0.007 OD) and respiratory burst activity (0.291 ± 0.020 O.D) were high in P. monodon fed D4 diet. Similar effects were observed for plasma protein concentration (68.00 ± 1.41 mg/ml), lysozyme activity (0.483 ± 0.014 U/ml) and bactericidal activity (81.0 ± 1.33%) in shrimp fed D4 diet. The results of the present investigation conclude that the probiotic product at a concentration of 4% was effective in elevating the growth and immune performances in shrimp P. monodon. [ABSTRACT FROM AUTHOR]

This study investigates the effects of different levels of commercial yeast glucan (CYG) on innate immune response, hematological parameters, in- testinal microbiota, growth performance and survival rate of white fish (kutum) fry. Specimens (1.1 ± 0.15 g) were randomly allocated into 15 tanks (100 L) at a density of 25 fish per tank and triplicate groups were fed either a basal control diet (0% CYG) or a basal diet supplemented with yeast (0.5, 1, 1.5 or 2% CYG) for 60 days. All dietary CYG levels significantly increased the innate immune responses (IgM levels and lysozyme activity) (P < 0.05) and the highest survival was observed in the 1 and 1.5% CYG group. Compared to the control group, CYG had no effects on RBC, Hct and Hb (P > 0.05), but WBC levels were significantly higher in CYG fed fish (P < 0.05). Microbiological assessment indicated that the viable culturable autochthonous and lactic acid bacteria (LAB) levels significantly elevated in 0.5 and 1% treatments. Our results indicated that low levels of dietary CYG (0.5 and 1 %) improved growth performance, body protein levels and survival rate compared to the control treatment (P < 0.05). These results indicate that CYG stimulates innate immune response, improves growth performance and modulates intestinal microbiota of kutum fry. Thus, we suggest that low level CYG may be used as a beneficial dietary supplement in kutum fry culture. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the effects of diet with different microbial concentrations on the growth and length-weight relationship of Trichopodus trichopterus. For this aim a study was designed with four experimental treatments and the control to evaluate different microbial concentrations on growth and length-weight relationship. The counts of bacteria that were used for dietary supplementation were 1×104, 2×104, 3×104 and 4×104 CFU g-1 in T1, T2, T3 and T4 treatments, respectively. The results indicated that the use of 3×104 CFU g-1 concentration increased the length, and a positive allometric growth was observed. The higher length frequency was estimated in T3. The results indicated that the use of micro- bial additives with proper concentration causes different allometric growth. [ABSTRACT FROM AUTHOR]

The study was conducted to assess the over-wintering growth performance of mixed-sex and mono-sex male tilapia, Oreochromis niloticus. The experiment was carried out with two treatments each with three replicates for a period of 6 months from October 2012 to March 2013 in the Field Laboratory Complex, Bangladesh Agricultural University. In the first treatment (T1), mixed-sex tilapia was stocked in 3 ponds with a mean initial weight of 4.80±0.18 g. In the second treatment (T2), mono-sex male tilapia was stocked in another 3 ponds with a mean initial weight of 4.81±0.20 g. Fish were fed at the rate of 6% of fish body weight at the beginning of the experiments, then the feeding rates were gradually reduced to 2% for the third month and finally increased to 3% for the rest of the period. Water parameters in terms of temperature, dissolved oxygen, pH, transparency, alkalinity, ammonia and nitrite were within the range of fish farming. After 6 months of culture period, mono-sex male tilapia attained a significantly (P<0.05) higher mean final weight and specific growth rate, compared to that of mixed-sex tilapia. However, there was no significant (P>0.05) difference of food conversion ratio and survival rate (%) values between the treatments. The benefit-cost ratio was calculated as 1.17 and 1.43 for mixed-sex and mono-sex male tilapia, respectively. The results suggested that it is possible to successfully culture tilapia during the winter period in Bangladesh, and the culture of mono-sex tilapia is more profitable due to its higher growth rate. [ABSTRACT FROM AUTHOR]

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A study was carried out from November 2010 to October 2011 in Tudakul reservoir, Uzbekistan. A total of 142 silver carps, Hypophthalmichthys molitrix Val., were sampled including 65 females and 77 males. The scale of silver carp is cycloid with straight edges. Annulus on scale of immature silver carp appears in March and of matured fish during the spawning period in the second half of May. The ages, total lengths and weights of the samples ranged between 1 to 5 years, 15 to 105 cm and 35 to 17,500 g, respectively. The relation between the total length (TL) and weight (W) was described by equation W = 0.0065xTL3.1572 (r=0.99). The relationship between the total length (TL) and the standard length (l) was described by a linear equation: l = 0.8973xTL - 1.571 (r = 0.99). The mean estimated total length of 1-yearold silver carp was 25.25 cm, 2-year-old, 49.81 cm, 3-year-old, 68.91 cm, 4-year-old, 89.94 cm, 5-year-old, 94.47 cm. The mean back calculated total length was 28.2 cm at age I, 56.2 cm, II, 71.18 cm, III, 89.56 cm, IV, 98.9 cm, V. R. Lee's phenomenon was not manifested as the fishing company is oriented to the catches of large fish. [ABSTRACT FROM AUTHOR]