Effect of fermentation on the nutritive value of sesame seed meal in the diets for rohu, Labeo rohita (Hamilton), fingerlings

Six isonitrogenous (350 g kg⁻¹ crude protein) and isoenergetic (17573 kJ kg⁻¹) experimental diets incorporating raw and fermented sesame ( Seasamum indicum ) seed meal at 200, 300, and 400 g kg⁻¹ into a fishmeal based diet were fed to rohu Labeo rohita fingerlings for 60 days and the growth performance and feed utilization efficiency of the fish was studied. The antinutritional factor phytic acid, from raw sesame seed meal, could be reduced below detection limit by fermentation with lactic acid bacteria ( Lactobacillus acidophilus ). Fermentation of the oilseed meal resulted in reduction of the tannin content from 20 to 10 g kg⁻¹. In terms of growth response, feed conversion ratio and protein efficiency ratio, a diet containing 400 g kg⁻¹ fermented sesame seed meal resulted in a significantly ( P  < 0.01) best fish performance. In general, growth and feed utilization efficiencies of fish fed fermented sesame seed meal diets were superior to those fed raw oilseed meal diets. Apparent protein digestibility (APD) values decreased with increasing levels of raw oilseed meal. APD was, however, significantly ( P  < 0.01) higher at all levels of incorporation of fermented sesame seed meal, while diets containing raw oilseed meal resulted in poor protein and lipid digestibility. Carcass protein and lipid contents of fish fed fermented sesame seed meal diets increased with increasing level of incorporation, being highest with 400 g kg⁻¹ fermented oilseed meal-containing diet. The results showed that sesame seed meal may be incorporated in carp diets up to 200 g kg⁻¹ and 400 g kg⁻¹ in raw and treated (fermented) forms respectively.     

Identification of gut‐associated amylase,cellulase and protease‐producing bacteria in three species of Indian major carps

Isolation and enumeration of amylase, cellulase and protease‐producing autochthonous bacteria in the proximal intestine (PI) and distal intestine (DI) of three species of Indian major carps, catla (Catla catla), mrigal (Cirrhinus mrigala) and rohu (Labeo rohita), were investigated using the conventional culture‐based technique. Population levels of amylolytic strains were the highest in the PI of catla and the lowest in the DI of rohu. The highest viable count of cellulase and protease‐producing bacteria was recorded in the DI and PI of mrigal respectively. Among the bacteria isolated, 10 strains (five from PI and five from DI) were selected as potent enzyme producers according to a quantitative enzyme assay. The chosen strains were further identified by 16S rRNA gene sequence analysis. The five strains isolated from catla showed high similarity to Citrobacter sp. clone W2, Enterobacter sp. JA24, Bacillus coagulans strain TR, uncultured bacterial clone Hel3bc04 and Bacillus cereus strain UST2006‐BC004. The four strains isolated from mrigal were most closely related to Bacillus sp. KCd2, uncultured bacterial clone Hel3bd09, B. cereus strain BU040901‐020 and Citrobacter freundii strain YRL11, while the strain isolated from rohu probably belonged to Bacillus sp. GV.     

Probiotic efficiency of Bacillus sp. in Labeo rohita challenged by Aeromonas hydrophila: assessment of stress profile,haemato‐biochemical parameters and immune responses

Fish are always susceptible to a wide variety of deadly pathogens which cause a huge loss in aquaculture industries. In this investigation, we have demonstrated the in vivo probiotic efficiency of Bacillus sp. MVF1 (GenBank Acc. No. KP256503) in Labeo rohita challenged with pathogenic strain of Aeromonas hydrophila (MTCC 1739). To check the probiotic potential of the selected bacterial strain, fish were divided into four groups: control, D1, D2 and D3. A total of 100 days (70 days probiotic feeding + 71th day sampling and 28 days challenged test + 29th day sampling) of feeding trial was conducted. To establish the probiotic potential of Bacillus sp. MVF1, certain haematological parameters (haemoglobin, total erythrocyte and leucocyte count), serum biochemical parameters (total protein, albumin and globulin), immune parameters (serum lysozyme and total IgM levels) and hepatic stress profile (malondialdehyde production, superoxide dismutase and catalase activity) have been measured. Our results demonstrated that red blood cell number, white blood cell number and haemoglobin content were much higher in D2 group fish compared to other groups and control fish. Similarly, total protein contents, albumin concentration, globulin concentration, lysozyme activity and IgM production were also recorded to be highest in D2 group fish. This finding clearly indicated the probiotic potential of Bacillus sp. MVF1 in L. rohita. Furthermore, our results also demonstrated that 1 × 10⁷ CFU g^?1 feed (D2) provides better immunity compared to 1 × 10⁵ (D1) and 1 × 10⁹ (D3). Due to beneficial effects, the bacterium Bacillus sp. MVF1 might be useful in aquaculture industries to reduce the disease susceptibility.     

Shrimp (Litopenaeus vannamei) production and stable isotope dynamics in clear‐water recirculating aquaculture systems versus biofloc systems

Closed recirculating aquaculture systems (RAS) offer advantages over traditional culture methods including enhanced biosecurity, the possibility of indoor, inland culture of marine species year‐round and potential marketing opportunities for fresh, never‐frozen seafood. Questions still remain regarding what type of aquaculture system may be best suited for the closed‐system culture of marine shrimp. In this study, shrimp (Litopenaeus vannamei) were grown in clear‐water RAS and in biofloc‐based systems. Comparisons were made between the system types with respect to water quality, shrimp production and stable isotope dynamics used to determine the biofloc contribution to shrimp nutrition. Ammonia and nitrite concentrations were higher, and shrimp survival was lower in the biofloc systems. Although stable isotope levels indicated that biofloc material may have contributed 28% of the carbon and 59% of the nitrogen in shrimp tissues, this did not correspond with improved shrimp production. Overall, the water column microbial communities in biofloc systems may be more difficult to manage than clear‐water RAS which have external filters to control water quality. Biofloc does seem to offer some nutritional contributions, but exactly how to take advantage of that and ensure improved production remains unclear.     

Effects of antimicrobial peptides on growth,feed utilization,serum biochemical indices and disease resistance of juvenile shrimp,Litopenaeus vannamei

This experiment was conducted to assess the effects of antimicrobial peptides at different levels (Diet 1 (0%), Diet 2 (0.1%), Diet 3 (0.2%), Diet 4 (0.4%), Diet 5 (0.6%) and Diet 6 (1%)), on growth, serum biochemical indices and antioxidant effect, feed utilization and disease resistance in Litopeneaus vannamei. There were four replicates in each group in the experiment (mean weight = 0.21 ± 0.00 g) and also fed with their respective diets for 8 weeks. Growth performance compared with the control group (0%) significantly increased at first and then decreased among treatment groups (p < .05) whereas the survival rate ranged from 78% to 96%. No significant differences were observed in terms of moisture, crude protein and ash content, but there was a significant increase in crude lipid (p < .05). In serum, acid phosphatase, alkaline phosphatase, polyphenol oxidase, triglyceride, glucose and total cholesterol changed as compared with 0%. Total antioxidant capacity, glutathione peroxidase, catalase, superoxide dismutase and malondialdehyde were also different from 0%. Disease resistance was increased in shrimp among treatment groups with 0.4% recording the lowest mortality percentage of 37% after the challenge test. The results from the present study suggested that supplementation of AMP at 0.4% in shrimp diet can improve growth performance, antioxidants activities and innate immune response of Pacific whiteleg shrimp.     

Hatch rate of channel catfish Ictalurus punctatus (Rafinesque 1818) eggs treated with 100 mg L−1 copper sulphate pentahydrate

Catfish hatcheries use copper sulphate pentahydrate (CuSO₄·5H₂O) as an economical control for saprolegniasis on eggs. This study determines hatch rate of channel catfish, Ictalurus punctatus (Rafinesque 1818), eggs in hatching troughs containing 23.8 °C flow‐through well water when treated with 100 mg L^?1 CuSO₄·5H₂O (10 times the proposed therapeutic dose). Eggs were treated daily until the embryos reached the eyed stage. Fry survival in the control and 100 mg L^?1 CuSO₄·5H₂O treatments was significantly different (15% and 71% respectively). This study demonstrates that there is a considerable margin of safety in using CuSO₄·5H₂O as a catfish egg treatment to control saprolegniasis.     

Managing fisheries is managing people: what has been learned?

Understanding the behaviour of fishermen is a key ingredient to successful fisheries management. The aggregate behaviour of fishing fleets can be predicted and managed with appropriate incentives. To determine appropriate incentives, we should look to successes to learn what works and what does not. In different fisheries incentive systems have been found to reduce the race‐for‐fish and make fisheries profitable, to stimulate stock rebuilding, to reduce bycatch, and to provide for reductions in illegal fishing. Yet, success can be evaluated in many dimensions, but is, in fact, rarely done – per cent overfished seems to be the dominant measure of performance. I evaluate the yield lost due to overfishing in several ecosystems and contrast the situation of North Atlantic cod where considerable yield is lost, to fisheries in New Zealand and the west coast of the USA where lost yield due to overfishing is very small. Much more systematic evaluation of the other aspects of fisheries performance is greatly needed. From examples explored in this paper I conclude that prevention of overfishing can be achieved with strong central governments enforcing conservative catch regulations, but economic success appears to require an appropriate incentive structure.     

Frame-shift deletions in patients with Duchenne and Becker muscular dystrophy

Duchenne muscular dystrophy (DMD) and its less severe form Becker muscular dystrophy (BMD) are allelic disorders. It has been suggested that in the mutations involving BMD, the translational reading frame of messenger RNA is maintained and a smaller, though partially functional, protein is produced. In order to test this, the exon-intron boundaries of the first ten exons of the DMD gene were determined, and 29 patients were analyzed. In a number of BMD patients (mild and severe BMD), the reading frame of messenger RNA was not maintained. On the basis of these findings, a model for reinitiation from an internal start codon is suggested.     

Impaired respiratory and body temperature control upon acute serotonergic neuron inhibition

Physiological homeostasis is essential for organism survival. Highly responsive neuronal networks are involved, but their constituent neurons are just beginning to be resolved. To query brain serotonergic neurons in homeostasis, we used a neuronal silencing tool, mouse RC::FPDi (based on the synthetic G protein-coupled receptor Di), designed for cell type-specific, ligand-inducible, and reversible suppression of action potential firing. In mice harboring Di-expressing serotonergic neurons, administration of the ligand clozapine-N-oxide (CNO) by systemic injection attenuated the chemoreflex that normally increases respiration in response to tissue carbon dioxide (CO(2)) elevation and acidosis. At the cellular level, CNO suppressed firing rate increases evoked by CO(2) acidosis. Body thermoregulation at room temperature was also disrupted after CNO triggering of Di; core temperatures plummeted, then recovered. This work establishes that serotonergic neurons regulate life-sustaining respiratory and thermoregulatory networks, and demonstrates a noninvasive tool for mapping neuron function.