Cent Survival Research Articles

Impact of moisture content of rice grain on infestation of angoumois grain moth, Sitotroga cerealella olivier

The influence of different levels of moisture content on survival of Sitotroga cerealella Olivier was studied in laboratory. It was observed that the initial moisture content of the grain played an important role in larval survival. The survival of the larvae increased significantly from 13.5 up to 17.8 per cent moisture content. It was observed that in pooled data of two years that the maximum larval survival was noticed in the rice grain moisture content having 17.8 per cent was 72.0 percent which was significantly superior over other grain moisture content. The grain with moisture content of 15.6 per cent recorded (57.0%) larval survival followed by the moisture content 13.5 per cent (43.5%). The lowest larval survival was observed in the grains having the grain moisture content of 7.2 per cent with 7.0 per cent survival. . KEYWORDS :Rice, grain,damage, Angoumois grain moth, Sitotroga cerealella Olivier, moisture content

Nursery-Rearing Trials of Giant Freshwater Prawn, <i>Macrobrachium rosenbergii</i>, in Earthen Ponds

Nursery-rearing trials of the giant freshwater prawn Macrobrachium rosenbergii were carried out in five newly-excavated earthen ponds of 400 m2 each wit stocking densities ranging from 16 to 28/m2. The prawns were fed daily with pelleted feed (30% crude protein) at 10% body weight. The juvenile prawns reached an average weight of 0.655 - 1.290 g after 46-50 days of rearing. The individual daily weight increments varied from 12.8 to 23.6 mg in different trials. Per cent survival in different ponds ranged from 52.80 to 85.20 with an average of 68.79.

Stionic interaction on leaf parameters and survival of grafted pear saplings

The present study was conducted to find the effect of different rootstock-scion combinations on multiplication of Pear (Pyrus communis) saplings. There were four scion cultivars and five rootstocks, constituting twenty treatment combinations. Data revealed that maximum leaf length and width were recorded in cv. Chinese Sandy Pear grafted on BA-29 and Pear sucker rootstocks. However, the minimum leaf length and width were recorded in cv. Carmen grafted on Quince and cv. Abate Fetel on BA-29 rootstocks. The highest leaf area (23.46 cm2) was recorded in cv. Chinese Sandy Pear on BA-29, while it was minimum (14.19 cm2) in cv. Abate Fetel on BA-29. Leaf chlorophyll content was highest (3.71 mg/g) in Chinese Sandy Pear grafted on Quince. Length (27.11 μm) and width (9.96 μm) of stomata were recorded maximum in cv. Abate Fetel grafted on Kainth and cv. William Bartlett grafted on Quince, respectively. In contrast, the stomatal density was maximum (20.63/μm2) in cv. Carmen grafted on Quince. Grafted saplings of cv. Abate Fetel on Quince , cv. Chinese Sandy Pear on BA 29 and cv. William Bartlett on Quince C rootstocks recorded 86.67 per cent survival compared to other grafts. More number of saleable plants was recorded when cv. William Bartlett was grafted on Quince (86.33%). The investigations concluded that pear varieties raised on Quince rootstock had higher values for all studied parameters, followed by Quince C rootstock.

FEEDING PREFERENCE OF BAGWORM, METISA PLANA WALKER (LEPIDOPTERA: PSYCHIDAE) ON FOUR DIFFERENT PALM SPECIES

A study was conducted to determine the feeding preference of the bagworm, Metisa plana on different palm species in no-choice and choice feeding tests. In the laboratory study, the larvae of bagworm, M. plana were fed with leaves of four palm species namely oil palm (Elaeis guineensis), coconut (Cocos nucifera), red sealing wax palm (Cyrtostachys renda) and salak (Salacca zalacca). In the no-choice feeding test, the bagworms were fed with leaves of each selected palm species and in the choice feeding test, the M. plana were fed in pairs with leaves of E. guineensis as a constant diet and each of C. nucifera, C. renda and S. zalacca respectively. Furthermore, the feeding preference of bagworms on E. guineensis and C. nucifera leaves was evaluated in a semi-field trial. The result of the laboratory study showed that C. nucifera was the most preferred host plant followed by E. guineensis, C. renda and S. zalacca. The M. plana fed with C. nucifera leaves recorded 28.83 cm2 and 22.01cm2 of total leaflet area consumed in the no-choice feeding test and choice feeding test respectively. The bagworms feeding on leaves of C. nucifera showed 33.33 per cent survival rate and were observed to have the fastest larval development and transformation to pupal stage. The leaves of C. nucifera were preferred over E. guineensis despite the latter being the observed host plant of this bagworm species. In no-choice assessments, the M. plana fed with E. guineensis leaves recorded a total leaf area consumption at 26.89 cm2 and showed only a 13.33 per cent survival rate. C. renda and S. zalacca leaves were recorded as the least preferred host plant and recorded a low leaf area consumption at 14.67cm2 and 11.40 cm2 in no-choice feeding and 1.29 cm2 and 5.05 cm2 in choice feeding respectively. The M. plana that were fed with the two respective palms did not survive to the pupal stage. In the semi-field study, similar results were obtained as C. nucifera was recorded as the more preferred host plant by the bagworm as compared to E. guineensis. The cumulative damage on the leaves of the palms was recorded at 29.37 per cent for C. nucifera and 13.13 per cent for E. guineensis. In the choice feeding test, the bagworms fed with leaves of C. nucifera recorded 12.71 per cent and that of E. guineensis at 8.19 per cent of cumulative damage. The percentage of survival rate of bagworms that were fed with C. nucifera leaves was recorded to be significantly higher (P<0.05) at 18.75 ± 2.16 per cent as compared to E. guineensis that recorded only 9.50 ± 1.53 per cent. Keywords: Bagworm, Metisa plana, feeding preference, oil palm, coconut, red sealing wax palm, salak palm.

Humoral immune response in Asian seabass vaccinated with inactivated and recombinant viral nervous necrosis vaccine

Viral nervous necrosis is a serious viral disease of marine and brackishwater finfish hatcheries. The red-spotted grouper nervous necrosis virus (RGNNV) is the most prevalent genotype among fishes in tropical and temperate regions. RGNNV was propagated in SSN-1 cell line and inactivated using BEI. The capsid protein of RGNNV was cloned and expressed in Escherichia coli and purified. Inactivated and recombinant VNN vaccines were produced by emulsifying the antigen with commercial adjuvant and administered to Asian seabass, Lates calcarifer, fingerlings and broodstock intraperitoneally. The immune response was assessed at regular intervals by indirect ELISA. The maternal antibodies in one-day post-hatch larvae obtained from the vaccinated and control broodstock were assessed by indirect ELISA. The larvae were subjected to challenge with virulent RGNNV and the relative per cent survival (RPS) was estimated. The efficacy of the vaccine was also assessed under field conditions. The recombinant vaccine produced significantly higher specific antibody levels than the inactivated vaccine in fingerlings and broodstock and the immune response was dose-dependent. Recombinant vaccine at 50 and 100 μg/fish produced significantly higher antibody levels and immune response could be observed as early as one-week post vaccination. Vaccinated broodstock produced larvae with maternal antibodies and had higher RPS when challenged at 18 days post-hatch. The vaccine produced a significant immune response even under field conditions. The vaccine can be used to vaccinate broodstock to reduce loss due to VNN in early larval stages.

Probiotic effects of Pseudoalteromonas ruthenica: Antibacterial, immune stimulation and modulation of gut microbiota composition

This study aimed to characterise and evaluate the probiotic properties of a newly isolated marine bacterium, strain S6031. The isolated strain was identified as Pseudoalteromonas ruthenica. In vivo experiments were conducted with P. ruthenica-immersed larvae and P. ruthenica-enriched Artemia fed to adult zebrafish. Disease tolerance of larval zebrafish against Edwardsiella piscicida was demonstrated by 66.34% cumulative per cent survival (CPS) in the P. ruthenica-exposed group, which was higher than the CPS of the control (46.67%) at 72 h post challenge (hpc). Heat-stressed larvae had 55% CPS in the P. ruthenica-immersed group, while the control had 30% CPS at 60 hpc. Immune-stress response gene transcripts (muc5.1, muc5.2, muc5.3, alpi2, alpi3, hsp70, and hsp90a) were induced, while pro-inflammatory genes (tnfα, il1b, and il6) were downregulated in P. ruthenica-immersed larvae compared to the control. This trend was confirmed by low pro-inflammatory and high stress-responsive protein expression levels in P. ruthenica-exposed larvae. Adult zebrafish had higher CPS (27.2%) in the P. ruthenica-fed group than the control (9.52%) upon E. piscicida challenge, suggesting increased disease tolerance. Histological analysis demonstrated modulation of goblet cell density and average villus height in the P. ruthenica-supplemented group. Metagenomics analysis clearly indicated modulation of alpha diversity indices and the relative abundance of Proteobacteria in the P. ruthenica-supplemented zebrafish gut. Furthermore, increased Firmicutes colonisation and reduced Bacteroidetes abundance in the gut were observed upon P. ruthenica supplementation. Additionally, this study confirmed the concentration-dependent increase of colony dispersion and macrophage uptake upon mucin treatment. In summary, P. ruthenica possesses remarkable functional properties as a probiotic that enhances host defence against diseases and thermal stress.

Soilless system: An approach for hybrid seed production in tomato (Solanum lycopersicum)

Soilless agriculture is one of the advanced techniques to cultivate plants without soil, with minimal water and nutrients, and helps in vertical growth of agricultural technology. It is an eco-friendly approach widely used for commercial cultivation of quality vegetables. An experiment was conducted at University of Agricultural Sciences, GKVK, Bengaluru, Karnataka during 2017–19 to evaluate the potentiality and suitability of the hydroponics (M2) and aeroponics (M3) methods over conventional method (M1) for hybrid seed production of tomato (Solanum lycopersicum L.). The experiment had 12 treatments comprising 3 methods of production, 2 parental lines (TAG 1F and TAG 2F) and 2 seed treatments (S1: Control and S2: thiram @2g/kg + chlorpyrifos @3g/kg). Hoagland nutrient solution with pH 5.5–6.5 was used for soilless systems. The results revealed that, among the parental lines, TAG 1F performed better under all the methods of hybrid seed production. Seed treatment increased the per cent survival rate to the tune of 3.26%. Aeroponics and hydroponics performed better than conventional method. Aeroponics showed significantly higher plant height (140.94 cm), fruit weight (124.54 g), total biomass (106.44 g) and test weight (0.39 g) while, hydroponics showed significantly higher number of fruit/plant (45.84) and SVI (2821). It is inferred that soilless agriculture could be a promising tool for quality and year-round healthy hybrid tomato seed production under protected cultivation.

Changing patterns of multidisciplinary team treatment, early mortality, and survival in colorectal cancer.

BackgroundThis study reports early mortality and survival from colorectal cancer in relation to the pattern of treatments delivered by the multidisciplinary team (MDT) meeting at a high-volume institution in England over 14 years.MethodsAll patients diagnosed with colorectal cancer and discussed during MDT meetings from 2003 to 2016 at a single institution were reviewed. Three time intervals (2003–2007, 2008–2012, and 2013–2016) were compared regarding initial surgical management (resection, local excision, non-resection surgery, and no surgery), initial oncological therapy, 90-day mortality, and crude 2-year survival for the whole cohort. Sub-analyses were performed according to age greater or less than 80 years.ResultsThe MDT managed 4617 patients over 14 years (1496 in the first interval and 1389 in the last). Over this time, there was a reduction in emergency resections from 15.5 per cent to 9.0 per cent (P < 0.0001); use of oncological therapies increased from 34.6 per cent to 41.6 per cent (P < 0.0001). The 90-day mortality after diagnosis of colorectal cancer dropped from 14.8 per cent to 10.7 per cent (P < 0.001) and 2-year survival improved from 58.6 per cent to 65 per cent (P < 0.001). Among patients aged 80 years or older (425 and 446, in the first and last intervals respectively) there was, in addition, a progressive increase in ‘no surgery’ rate from 33.6 per cent to 50.2 per cent (P < 0.0001) and a reduction in elective resections from 42.4 per cent to 33.9 per cent (P = 0.010). The 90-day mortality after elective resection fell from 10.0 per cent (18 of 180) to 3.3 per cent (5 of 151; P = 0.013).ConclusionsSurvival from colorectal cancer improved significantly over 14 years. Among patients aged ≥80 years, major changes in the type of treatment delivered were associated with a decrease in postoperative mortality.

A blend of Guava, Bitter, and Neem Leaf extracts improves haematology and resistance to co-infection of Streptococcus agalactiae and Aeromonas jandaie but not Liver health in Nile tilapia

Given the intense interest in the use of herbal extracts to improve fish growth, fish health, and disease resistance in fish in culture systems, in this study, we examined the effects of a blend of Guava, Bitter and Neem leaf extracts (GBNL) (i.e., 1:1:1 for GL, BL, and NL respectively) at different inclusion (i.e. 0 GBNL gkg−1, 1 GBNL gkg−1, 3 GBNL gkg−1, 5 GBNL gkg−1, 7 GBNL gkg−1 and 10 GBNL gkg−1) levels on growth, haematology, immunity, liver toxicity and resistance to bacterial co-infections in Nile tilapia. After 8 weeks of feeding, Nile tilapia fed 3 GBNL gkg−1 diets showed significant effects in improving weight gain compared to those fed the control diet. GBNL fed fish showed improved health of fish by stimulating significant increases in levels of White blood cells, Red blood cells, Haemoglobin, and Haematocrit in relation to those fed the control diet. Also, the applications of deferent GBNL levels in Nile tilapia diets showed the potential to upregulate the expression of the immune-related genes heat shock protein 70, chicken type lysozymes, and Beta-defensin, with significant effects shown in fish fed 5GBNL gkg−1 diets in comparison to the control. The results also indicate that GBNL supplementation can decrease mortalities to co-infection of Streptococcus agalactiae and Aeromonas jandaie in Nile tilapia with the lowest mortalities of 13.65% and relative per cent survival of 82.57 % in fish fed 5GBNL gkg−1. Despite the potential of GBNL applications in Nile tilapia, findings of this study indicate fish fed the different concentrations of GBNL, particularly with 7 GBNL gkg−1 can promote the leaching of the liver enzymes: alanine transaminase, aspartate aminotransferase, and alkaline phosphate into the bloodstream which is suggestive of potential liver damage in Nile tilapia. Histological examinations of a cross-section of the liver tissues of fish fed GBNL showed various injuries including hydropic changes, pyknosis nuclei, erythrocytes congestion and vacuolation with the severest seen in those fed 7 GBNL gkg−1. Taking all of the above into consideration, 5GBNL gkg−1 application could improve the health and disease resistance of Nile tilapia; however, prolong use thus after 8 weeks of administration could be injurious to fish liver health.

Mid-life alcohol consumption and survival to age 90 in men: The Tromsø Study 1979-1980 with follow-up to 2019.

The Tromsø Study 1979-1980 collected information on alcohol (beer, wine and spirits) consumption frequency and inebriation frequency, and the oldest male participants (aged 50-54 years) were followed for all-cause mortality. This study aimed to identify the impact of habitual alcohol consumption in mid-life on reaching up to 90 years of age. Among the study sample of 778, a total of 120 (15.4%) men reached the age of 90. The most common reported alcohol consumption frequency was 'never or a few times a year', and 18.9% of those in this group reached 90 compared with 11.9% of those who reported a more frequent beer consumption. Fifty per cent survival in these groups was 80.5 and 76.9 years, respectively. The pattern was similar for spirits consumption and for inebriation but not for wine consumption. Number of deaths increased gradually with increasing beer and spirits consumption frequency and with inebriation frequency. We observed no J-shape or pattern that revealed a beneficial influence of light alcohol consumption. Daily smoking, physical inactivity, marital status, blood pressure and total cholesterol reduced the contribution of alcohol consumption to a small degree. This study shows that all beer and spirits consumption frequencies in mid-life affect later life and total lifespan. Refraining from alcohol consumption or drinking only a few times a year increases one's chances of living longer, and the chance of reaching 90 years of age is 1.6-fold higher than in those with more frequent alcohol consumption.

Immunoproteomic identification of OmpA with potential stimulation of serum‐specific antibody in Nile tilapia ( Oreochromis niloticus ) and its ability to protect against Edwardsiella ictaluri infection

Edwardsiella ictaluri is a Gram-negative bacterium that has been reported to be disease causing in several economic fish including Nile tilapia. Here, immunoproteomic identification found that outer membrane protein A (OmpA) could react with serum from fish naturally infected with E. ictaluri. The expression and production of recombinant OmpA protein could be successfully conducted in Escherichia coli strain BL21(DE3) with the molecular mass of 38 kDa after inclusion bodies were successfully solubilized and refolded. Immunization of fish with the recombinant OmpA protein showed that the recombinant proteins could induce the production of specific antibodies in serum of immunized fish (p < 0.05) at 1-week postimmunization (7 dpi) and reached the highest antibody titre at 3 weeks postimmunization (21 dpi). The serum-specific antibody from fish immunized with the recombinant OmpA exhibited bacterial agglutination property. Furthermore, the partial protection of Nile tilapia was observed in OmpA immunized fish with the relative per cent survival (RPS) of 39.81%. In summary, this study explored the immunoproteomic method as a starting point to investigate OmpA of E. ictaluri and might be considered as a candidate protein for recombinant vaccine development in Nile tilapia against this bacterial infection.

Characterization and protective effects of lytic bacteriophage pAh6.2TG against a pathogenic multidrug-resistant Aeromonas hydrophila in Nile tilapia (Oreochromis niloticus).

Bacteriophage (phage) is considered as one of the alternatives to antibiotics and an environmentally friendly approach to tackle antimicrobial resistance (AMR) in aquaculture. Here, we reported isolation, morphology and genomic characterizations of a newly isolated lytic phage, designated pAh6.2TG. Host range and stability of pAh6.2TG in different environmental conditions, and protective efficacy against a pathogenic multidrug-resistant (MDR) Aeromonas hydrophila in Nile tilapia were subsequently evaluated. The results showed that pAh6.2TG is a member of the new family Chaseviridae which has genome size of 51,780bp, encoding 65 putative open reading frames (ORFs) and is most closely related to Aeromonas phage PVN02 (99.33% nucleotide identity). The pAh6.2TG was highly specific to A. hydrophila and infected 83.3% tested strains of MDR A. hydrophila (10 out of 12) with relative stability at pH 7-9, temperature 0-40°C and salinity 0-40 ppt. In experimental challenge, pAh6.2TG treatments significantly improved survivability of Nile tilapia exposed to a lethal dose of the pathogenic MDR A. hydrophila, with relative per cent survival (RPS) of 73.3% and 50% for phage multiplicity of infection (MOI) 1.0 and 0.1, respectively. Phage treatment significantly reduced the concentration of A. hydrophila in both water and fish body. Interestingly, the surviving fish from A. hydrophila challenged groups provoked specific antibody (IgM) against this bacterium. In summary, the findings suggested that the lytic phage pAh6.2TG is an effective alternative to antibiotics to control MDR A. hydrophila in tilapia and possibly other freshwater fish.

Development of Protocol for Propagation of &lt;i&gt;Zanthoxylum alatum&lt;/i&gt; through Mound Layering

Zanthoxylum alatum (commonly known as Timur, Timru, Tomar) is an important medicinal plant found in the warmer valleys of the Himalayas, parts of north-east and eastern India. Propagation through shoot cuttings is one of the most common methods of vegetative propagation in many woody species. This study was initiated to investigate the potential of mound layering as an alternative vegetative propagation method for propagating many hard to root plants without requiring expensive equipment and it has been successfully used in horticulture on many species. The simplicity of this method makes it fascinating to test it for multiplication of Z. alatum. Results from wounding was found to have a significant ( p≤0.05 ) effect on bud sprout, number of shoots per stools, shoot length and diameter, rooting per cent, number of roots, root length and per cent survival of the rooted shoots during spring season. Girdling proved to be the most effective method of wounding that yielded greatest number of shoots, rooting per cent, shoot length, shoot diameter, number of roots, root length and per cent survival. Furthermore, girdling method resulted in better survival of rooted shoots (65.20%) than random wounding (49.76%). Among IBA treatments, greater survival rate was achieved with 6000 ppm IBA (48.71%) in comparison with control (42.74%). It was therefore felt necessary to develop protocols for vegetative propagation of this species through cuttings and mound layering with the goal of working out multiplication rates by both methods.

Modulation of growth, skin mucus and serum immunities, and disease resistance of Nile tilapia fed host‐associated probiotic (Lactobacillus paracasei l61‐27b)

The experiment was performed to examine the effect of Lactobacillus paracasei l61-27b (LP) isolated from Nile tilapia intestine on the growth rate, skin mucus and serum immune parameters and disease resistance. Fish (25.40 ± 0.33 g) were distributed into glass tank (150 litres tank−1) at 20 fish tank−1 and fed with different levels of dietary L. paracasei l61-27b: 0 (LP1), 106 (LP2), 107 (LP3), 108 (LP4) and 109 CFU mL−1 (LP5) for 8 weeks. The results indicated that SGR, WG and FW significantly improved, while FCR significantly decreased, in fish fed LP supplemented. Dietary L. paracasei significantly increased SMLA and SMPA with the highest values recorded for fish in LP4 and LP5 groups. Similarly, SL, SP, ACH50, PI and RB were significantly stimulated in fish fed LP diet compared with fish fed control diet. Challenge study showed that in comparison with the control diet (20% survival), the survival rates of fish fed the L. paracasei were significantly (p < 0.05) higher; by 63.33% (LP2), 66.67% (LP3), 80.00% (LP4) and 83.33% for LP5. The relative per cent survival (RSP) was 54.17%, 58.33%, 75% and 79.17% in LP2, LP3, LP4 and LP5, respectively. In conclusion, the dietary inclusion of L. paracasei can be potentially used in Nile tilapia to improve its growth and health status.

Virulence and immunogenicity of blue catfish alloherpesvirus in channel, blue and blue×channel hybrid catfish.

Blue catfish alloherpesvirus (BCAHV) is a novel virus isolated from the blue catfish (Ictalurus furcatus). To date, the ultrastructure, virulence and immunogenicity of BCAHV have not been reported. Given the importance of blue catfish in producing channel ♀ (I. punctatus)×♂ blue (I.furcatus) catfish hybrids and the increasing demand for hybrid catfish in the US catfish industry, the susceptibility of blue, channel and hybrid catfish to BCAHV was assessed. Further, the cross-protective potential of BCAHV against Ictalurid herpesvirus 1 (IcHV1) was investigated in channel and hybrid catfish that survive BCAHV exposure. Neutralization assays revealed BCAHV is refractive (neutralization index [NI]=0) to anti-IcHV1 monoclonal antibody Mab 95, compared to IcHV1 (NI=1.8). Exposure of blue catfish fingerling to 1.3×105 TCID50 /L BCAHV produced cumulative mortality of 51.67±0.70% and pathologic changes similar to those of channel catfish virus disease. No mortality was observed in channel or hybrid catfish. Twenty-eight days post-challenge, surviving channel and hybrid catfish were exposed to 9.4×104 TCID50 /L IcHV1 (LC50 dose), resulting in 100% relative per cent survival compared to naïve cohorts. These data provide baseline information for BCAHV and lay the groundwork for future studies. Data also identify BCAHV as a potential vaccine candidate against IcHV1. Based on host range and immunogenicity evaluations, in addition to genome sequence data from previous studies, BCAHV should be given consideration as a new species of Ictalurivirus.

Identification and application of T3SS translocation signal in Edwardsiella piscicida attenuated carrier as a bivalent vaccine.

Type III secretion system (T3SS)-dependent translocation has been used to deliver heterologous antigens by vaccine carriers into host cells. In this research, we identified the translocation signal of Edwardsiella piscicida T3SS effector EseG and constructed an antibiotic resistance-free balanced-lethal system as attenuated vaccine carrier to present antigens by T3SS. Edwardsiella piscicida LSE40 asd gene deletion mutant was constructed and complemented with pYA3342 harbouring the asd (aspartate β-semialdehyde dehydrogenase) gene from Salmonella. Fusion proteins composed of EseG N-terminal 1-108 amino acids and the TEM1-β-lactamase reporter were inserted in plasmid pYA3342. The fusion protein could secrete into the cell culture, translocate into HeLa cells, and localize in the membrane fraction. Then, the double gene deletion mutant LSE40ΔasdΔpurA was constructed as an attenuated vaccine carrier, and Aeromonas hydrophila GapA (glyceraldehyde-3-phosphate dehydrogenase) was fused with the translocation signal, instead of the TEM1-β-lactamase reporter. The bivalent vaccine could protect blue gourami (Trichogaster trichopterus) against E. piscicida and A. hydrophila, with the relative per cent survival of 80.77% and 63.83%, respectively. These results indicated that EseG N-terminal 1-108 amino acid peptide was the translocation signal of E. piscicida T3SS, which could be used to construct bivalent vaccines based on an attenuated E. piscicida carrier.

Characterization ofStreptococcus iniaeghost vaccine and its immunization in Nile tilapia (Oreochromis niloticus)

Streptococcus iniae (S. iniae) is a Gram-positive bacterium associated with disease in several commercial species and other animals including humans. This zoonotic pathogen has led to high worldwide morbidity and mortality and huge economic losses in aquaculture. Here a S. iniae ghost (SIG) vaccine was successfully generated with a chemical method, and its immunogenicity and protective efficacy were examined in this study. The results showed that the titres of immunoglobulin M (IgM) in serum were significantly higher in group A (SIG-immunized) than group B (formalin-inactivated S. iniae, FSI-immunized), which was significantly higher than the control group (PBS-treated). Also, the phagocytic activity was significantly higher in group A than group B, which was significantly higher than the control group. Moreover, AKP activity and lysozyme activity of serum in group A were significantly higher than group B, which was significantly higher than the control group. Also, IL-1β, IFN-γ and HSP70 in the head kidney of fish immunized with SIG and FSI showed significantly higher than the control group throughout the whole experimental period. In addition, IL-1β and IFN-γ in the spleen of fish immunized with SIG showed significantly higher than that of in the FSI-immunized fish. Most important, the survival rate and relative per cent survival of group A were higher than group B, and both of them were all significantly more protected against the S. iniae challenge compared to the PBS-treated group. These results suggest that immunization with SIG induces immune responses and provides protection against a virulent S. iniae challenge.

First assessment of water quality of an artificial lake for fish culture and irrigation: A case study of water reuse in water shortage area across the Middle East

Although the application of treated wastewater in irrigation is a common practice in Jordan, there are no studies on its use in fish culture. In this study, physical, chemical and biological characteristics of an artificial lake containing mixture of treated wastewater and rainwater were assessed to examine whether the nutrient loading is sufficient for fish culture. The study also evaluated the suitability of the lake's water quality for irrigation after fish farming. The study was conducted in outdoor tanks fed with water from the artificial lake and stocked with three types of fish (Tilapia, Carp and Koi). The diversity of phytoplankton communities in the lake's produces natural food for Carp and Koi and promotes their growth with maximum per cent survival of 89% and 56% respectively. In addition, remarkable improvement in all water quality parameters after fish culture was observed.

Recombinant viral proteins delivered orally through inactivated bacterial cells induce protection in Macrobrachium rosenbergii (de Man) against White Tail Disease.

White tail disease (WTD) is a disease of Macrobrachium rosenbergii caused by Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) with the potential to devastate the aquaculture industry. The present study aimed to explore the possible protection of M. rosenbergii against the disease by oral administration of bacterially expressed recombinant capsid proteins of MrNV and XSV. Juvenile M.rosenbergii were fed with the feed coated with inactivated bacteria encapsulated expressed recombinant viral proteins either individually or in combination for 7days. Challenge studies using WTD causing agents were carried out after 3 (group I), 10 (group II) and 20 (group III) days post-feeding of viral proteins. Recombinant capsid protein of MrNV showed better protection when compared to other treatments with relative per cent survival of 62.5% (group I), 57.9% (group II) and 39.5% (group III). Treatment controls of groups I, II and III showed 100%, 95% and 95% mortality, respectively. The study demonstrates that oral administration of recombinant capsid proteins of MrNV and XSV provides effective protection against WTD in freshwater prawn.

Elucidating the Efficacy of Vaccination against Vibriosis in Lates calcarifer Using Two Recombinant Protein Vaccines Containing the Outer Membrane Protein K (r-OmpK) of Vibrio alginolyticus and the DNA Chaperone J (r-DnaJ) of Vibrio harveyi.

Recombinant cell vaccines expressing the OmpK and DnaJ of Vibrio were developed and subsequently, a vaccination efficacy trial was carried out on juvenile seabass (~5 cm; ~20 g). The fish were divided into 5 groups of 50 fish per group, kept in triplicate. Groups 1 and 2 were injected with 107 CFU/mL of the inactivated recombinant cells vaccines, the pET-32/LIC-OmpK and pET-32/LIC-DnaJ, respectively. Group 3 was similarly injected with 107 CFU/mL of inactivated E. coli BL21 (DE3), Group 4 with 107 CFU/mL of formalin killed whole cells V. harveyi, and Group 5 with PBS solution. Serum, mucus, and gut lavage were used to determine the antibody levels before all fish were challenged with V. harveyi, V. alginolyticus, and V. parahemolyticus, respectively on day 15 post-vaccination. There was significant increase in the serum and gut lavage antibody titers in the juvenile seabass vaccinated with r-OmpK vaccine. In addition, there was an up-regulation for TLR2, MyD88, and MHCI genes in the kidney and intestinal tissues of r-OmpK vaccinated fish. At the same time, r-OmpK triggered higher expression level of interleukin IL-10, IL-8, IL-1ß in the spleen, intestine, and kidney compared to r-DnaJ. Overall, r-OmpK and r-DnaJ triggered protection by curbing inflammation and strengthening the adaptive immune response. Vaccinated fish also demonstrated strong cross protection against heterologous of Vibrio isolates, the V. harveyi, V. alginolyticus, and V. parahaemolyticus. The fish vaccinated with r-OmpK protein were completely protected with a relative per cent of survival (RPS) of 90 percent against V. harveyi and 100 percent against V. alginolyticus and V. parahaemolyticus. A semi-quantitative PCR detection of Vibrio spp. from the seawater containing the seabass also revealed that vaccination resulted in reduction of pathogen shedding. In conclusion, our results suggest r-OmpK as a candidate vaccine molecule against multiple Vibrio strain to prevent vibriosis in marine fish.