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The aim of this study was to characterize whitefish and peled populations in Miedwie Lake by means of the genetic analysis of ND-1 (NADH dehydrogenase 1) gene and the ITS-1 (internal transcribed spacer 1) region in order to distinguish native forms from whitefish/peled hybrids. In the analysis, archival specimens of Coregonus lavaretus maraena from the Berlin Museum für Naturkunde were used. Genetic analysis performed with the aid of MEGA 4.0 software explicitly indicated that samples from Miedwie Lake belonged entirely to a native (rapidly growing) form of whitefish. Furthermore, the conducted research has also provided crucial information for a C. lavaretus management program for Miedwie Lake.

Pseudomonas sp. HIB_D has been observed to have nitrification activity that can oxidize ammonia/ammonium to nitrite and nitrate. This bacterium was isolated from the aquaculture environment with Ancol Indonesian marine water sources. Pseudomonas sp. HIB_D was applied in the rearing water of Litopenaeus vannamei to decrease nitrogen pollution levels and support a sustainable cultivation environment. This present study was set up using a completely randomized design with four treatments and three replications, i.e., control (without bacterial application) and bacterial application with a cell density of 107, 108, and 109 CFU mL−1 in a volume of 100 mL for 90 L seawater treatment. Thirty-six individuals of 15-day-old postlarvae L. vannamei (PL 15) (a density of 120 PL m-2) were used in this study for an 8-week rearing period. Based on the water quality analysis, the ammonia level under the bacterial applications was lower than in the control after 8-week cultivation. Nitrate levels increased at week 6 and decreased at week 8, specifically in 109 CFU mL−1 treatment. L. vannamei with 109 CFU mL−1 bacterial application had the best production performance with a survival rate of 94.33 ± 2.78%, an absolute length gain of 10.59 ± 0.22 cm, an absolute weight gain of 8.16 ± 0.33 g, a specific growth rate of 14.12% ± 0.01% day−1, and a feed conversion ratio of 1.26 ± 0.03. The blood glucose level and total hemocyte count of shrimp under the bacterial application with a density of 109 CFU mL−1 showed the highest level (30.71 ± 13.9 mg dL−1) and the lowest level (15 × 106 cells mL−1), respectively. The results showed that all treatments performed better than the control, in which the 109 CFU mL−1 bacterial application was the best treatment.

We are presently culturing the 4th generation of thecuttlefish, Sepia officinalis in our laboratory. A firstgeneration (F1) was grown from eggs collected from the wild (Ria Formosa–South Portugal) during the summer, at mean temperatures of 27°C ± 3°. In the present study, a second generation(F2), originated from eggs laid in the laboratory by females from F1 wascultured between the start of autumn and the end of spring, at meantemperaturesof 15 °C ± 4 °C. The life cycle ofcuttlefish from F2 was compared to F1. Populations of 30 cuttlefish were usedineach experiment. Cuttlefish were grown from one day old until the cycle wascompleted (when the last female in each population had died). Cuttlefish fromF2cultured at much lower temperatures had a longer life cycle, of almost 9 months(260 days) compared to cuttlefish from F1, which completed their cycle in lessthan 6 months (165 days). Cuttlefish from F2 grew significantly larger (U =0.00; p < 0.01) with mean weights of 343.3 ± 80.5 g and248 ± 33.1 g for males and females, respectively, comparedtoF1 (199.6 ± 40 g and 143.3 ± 30.9 g formales and females, respectively). Females from F2 had higher fecundity (225eggsfemale−1) compared to females from F1 (144 eggs perfemale−1), produced bigger eggs (t = 45.60752; p < 0.0001),weighing 0.74 ± 0.18 g, compared to 0.46 ± 0.11 fromF1,and bigger hatchlings (t = 7,144783; p < 0.0001), weighing 0.10 ±0.02g, compared to 0.09 ± 0.02 g for the summerpopulation.

This study aimed to determine the effective dose of Nodulisporium sp. KT29 metabolite for enhancing the production and innate immunity of Pacific white leg shrimp (Litopenaeus vannamei) against co-infection of white spot syndrome virus (WSSV) and Vibrio harveyi. Nodulisporium sp. KT29 isolate used in this study was a marine algicolous fungus isolated from Euchema edule. A field-scale experiment was conducted in floating net cages for 30 days using postlarvae 10 (0.0032 ± 0.01 g/shrimp) as experimental animals. This experiment tested three doses of Nodulisporium sp. KT29 metabolite including 0 (control), 10 (L10), and 20 mL/kg feed (L20) in triplicate. The metabolite was orally administered to the shrimp. A laboratory-scale experiment was conducted in controlled tanks with co-infection of WSSV and V. harveyi for 10 days, consisting of four treatments of Nodulisporium sp. KT29 metabolite including 0 (C + : positive control and C-: negative control), L10, and L20 in triplicate. The observation parameters in the challenge test included survival and immunological parameters consisting of phenoloxidase activity (PO) and respiratory burst (RB). The shrimp fed with fungal metabolite showed better results in zootechnical parameters than those of control. Innate immunity of shrimp was positively affected by Nodulisporium sp. KT29 metabolite, demonstrated by the higher pre-challenge test and post-challenge test PO and RB of treated groups than those of C + and C-. Conclusively, a low dose of Nodulisporium sp. KT29 metabolite could enhance the production and innate immunity of Pacific white leg shrimp against the co-infection of WSSV and V. harveyi.

In this study, inbreeding population was constructed by full-sib mating of “Huang Hai No. 2” core population in Fenneropenaeus chinensis. Growth and survival of three different stages were studied in three populations, including selected population, inbreeding population, and wild population. The growth experimental results show that body weight of selected population in all the three growth stages was significantly higher than those of inbreeding population and wild population (P < 0.05). At day 90, body weight of the selected population increased by 13.1 and 19.4%, compared with those of inbreeding population and wild population and the specific growth rate (SGR) for body weight of three populations were 2.24, 2.16, and 2.11. Coefficient of variation of body weight among the three populations were different; the highest was 23.75% in the selected population and the lowest was 16.76% in the wild population, which showed that there is potentiality for further selection. The survival results indicated that the difference of survival of the three populations were significant (P < 0.05), that of the selected population increased by 10.78 and 14.20%, compared with those of inbreeding population and wild population, and the average survival rate of the three populations were 74, 66.8, and 64.8%, respectively. Full-sib matings revealed that the amount of inbreeding depression of body weight varied from −7.68 to −11.53%, and the estimated average inbreeding depression coefficient was −4.61 per 10% increase of inbreeding coefficient of F. For survival trait, the estimated average inbreeding depression coefficient ranged from −2.62–3.81%, and the inbreeding depression was −1.05 per 10% increase of inbreeding coefficient of F, lower than the estimate obtained for growth. These results suggest that selection works well in the breeding program of F. chinensis, and inbreeding especially full-sib matings should be avoided in the following breeding programs.

Microalgal density is one of the factors affecting bioremediation efficiency, but literature on the density that efficiently removes nitrogen and phosphorus from aquaculture wastewater is still very limited. Thus, this study was conducted to optimize the density of Isochrysis galbana, Nannochlorum sp., and Tetraselmis tetrahele to efficiently remove inorganic N (NH3-N, NO2-N) and P. Three densities such as low, medium, and high with an optical density at 680 nm of 0.1, 0.2, and 0.3, respectively, were evaluated for 12 days. Results showed that medium density was good for Isochrysis galbana and Nannochlorum sp. in the removal of both N and P with rates reaching 97.93% and 84.07%, 94.25% and 93.39%, and 59.39% and 71.65% for NH3-N, NO2-N, and P, respectively. For Tetraselmis tetrahele, the low density efficiently removed N, while the high density effectively removed P with the highest removal of 99.16%, 97.5%, and 51.55% for NH3-N, NO2-N, and P, respectively. Specific growth rates of Isochrysis galbana and Tetraselmis tetrahele were affected by density; the lower the densities, the higher their growth rates. The three densities did not differ significantly in Nannochlorum sp. Isochrysis galbana and Nannochlorum sp. biomass productivity were high in medium and high densities, while low and medium densities for Tetraselmis tetrahele. Overall, the optimization of microalgal density is beneficial in the efficient removal of nitrogen and phosphorus from aquaculture wastewater.

India has taken a huge leap in the seaweed aquaculture sector, and Kappaphycus alvarezii is the most prominent carrageenophyte cultivated so far. With the ever-increasing demands for seaweed feedstock, the quality of planting material would determine the extent of the expansion of commercial farming. The current study is a sequel to our previous investigation on the long-distance transport of K. alvarezii planting material. The present work determines the effect of a bio-stimulant AMPEP (Ascophyllum Marine Plant Extract Powder) in imparting tolerance to the translocated planting material against desiccation. Various regulatory components like phytohormones; antioxidant enzymes (CAT, APX, GR); and metabolic components were assessed for day 0 (immediately after translocation) and day 1 (after 24 h of rehydration). It was observed that more than 84% moisture content was retained in translocated and AMPEP-treated translocated samples. After 24 h of rehydration, the catalase activity increased from 45,343.3 Unit mg protein−1 in the control to 146,148 and 321,489.1 Unit mg protein−1 in translocated and AMPEP-treated translocated biomass respectively. Similarly, ascorbate peroxidase activity increased from 0.3 Unit mg protein−1 to 2 Unit mg protein−1 in translocated and 1.3 Unit mg protein−1 in AMPEP-treated translocated biomass on day 1, which is significantly higher than their respective day 0 values. Glutathione reductase activity, on the other hand, decreased significantly on day 1 as compared to day 0. The activity increased significantly from 18.9 Unit mg protein−1 to 25.7 and 276 Unit mg protein−1, respectively, in translocated and AMPEP-treated translocated biomass. Similarly, the concentration of metabolites palmitic and benzoic acids, which help the cells against oxidative stress, also increased significantly in AMPEP-treated translocated biomass. Auxin and cytokinin concentrations however decreased in AMPEP-treated translocated biomass on day 1 as compared to translocated. The implementation of management practice based on the study would ultimately lead to the enhancement of livelihood prospects of the coastal communities involved in seaweed farming.

The effect of betel (Piper betle) and amla (Phyllanthus emblica) leaf extracts as feed supplement was studied on the growth and immune functions of the shrimp Penaeus monodon when exposed to a virulent strain of Vibrio parahaemolyticus. Six experimental groups (PB-1, PB-2, PB-3 and PE-1, PE-2, PE-3) of shrimp were fed extract at varying concentrations, 0.05%, 0.1%, and 0.2%, before being compared to a control group that did not receive any extract. After a feeding trial of 4 weeks, each group of shrimp was challenged with V. parahaemolyticus at a concentration of 106 CFU/mL and monitored for 2 weeks. The lowest concentration of P. betle extract and the moderate concentration of P. emblica extract in the diet induced a significant increase in shrimp growth performance parameters (final body weight, weight gain, specific growth rate) and feed utilization efficiency (low feed conversion ratio, high protein efficiency ratio). The dietary extracts also exhibited a significant positive influence on the immunological parameters such as total haemocyte count, prophenoloxidase activity, and superoxide dismutase activity before and after the challenge with V. parahaemolyticus. Compared to the control group, the total Vibrio load was significantly lower in the shrimp groups fed with extracts with the highest Vibrio density found in the hepatopancreas. The cumulative mortality of shrimp fed with extracts during 14 days decreased significantly, whereas control shrimps displayed 100% mortality upon V. parahaemolyticus challenge. In summary, we propose that a diet supplemented with P. betle and P. emblica leaf extract improves the growth of shrimp, and improves their immunity as is evident from their decreased susceptibility to V. parahaemolyticus infection.

Heat shock proteins (Hsps) are highly conserved proteins whose expression can be induced by high temperature and play an important role in a variety of biological processes. However, systematic identification of the Hsp60/10 and small Hsp (sHsp) gene family in rainbow trout has not yet been reported, and there is little available information about its roles in evolution in rainbow trout, a typical economical cold-water fish. In this study, we performed a comprehensive analysis of the rainbow trout Hsp60/10 and sHsp gene family and to investigate their expression profiles. A total of one Hsp60 gene, one Hsp10 gene, and ten sHsp genes were identified. According to RNA-seq analysis of rainbow trout liver and head kidney under heat stress, a total of six out of ten sHsp genes were significantly upregulated in liver and head kidney. Real-time RT-PCR (RT-qPCR) was used to quantitatively analyze the expression levels of these genes in different tissues of rainbow trout. Results showed that the expression of hspe1 and hspd1 was lowest in liver and gill, respectively, and highest in brain. In sHsp gene family, all genes are highly expressed in the liver and head kidney, but relatively low in the heart, spleen, brain, gills, and muscles. This systematic analysis provided valuable information about the diverse roles of Hsp60/10 and sHsp in the evolution of teleost fish, which will contribute to the functional characterization of Hsp60/10 and sHsp genes in further research.