The algae Ulva lactuca and Gracilaria parvispora are abundant in the Gulf of California, rich in nutrients, and may be used as a source of protein in balanced diets for shrimp. This study tests ...whether their meal, as a partial inclusion in diets for juvenile Litopenaeus vannamei, is feasible. Percentages of inclusion were 5, 10, and 15 %. Results showed that final weight, weight gain, and specific growth rate varied significantly among diets (P < 0.05). There were significant differences in growth among the trials of amount of inclusion of meal when using U. lactuca (P < 0.05), and no significant differences among the trials when using G. parvispora (P > 0.05). In general, better results were obtained when using G. parvispora compared with U. lactuca. When compared to the control diet (without inclusion), diets that included 10 and 15 % U. lactuca meal yielded a significantly lower growth (P < 0.05), but no significant differences were detected when using U. lactuca 5 % meal (P > 0.05), suggesting the feasibility of inclusion to this limited percentage. No significant differences were detected between the control and the three treatments with G. parvispora, suggesting the possibility of using higher percentages of inclusion. We conclude that both seaweeds may be used as a component in preparing feed for juvenile L. vannamei.
This research aims to evaluate the effect of molasses as a source of organic carbon on the growth and lipid profile of Dunaliella salina cultivated under different light regimes to determine its ...strategy and potential use to produce biodiesel. Two sources of nutrients (F/2 medium, F/2; molasses, M) and two light conditions (12 h light: 12 h darkness, 12L:12D) conformed four treatments (F/2 12L:12D, F/2 D, M 12L:12D, and MD) that were investigated with three replicates each. The concentration of microalgae produced by the groups under light conditions was more than double that of those grown in darkness. The highest biomass produced (46.91 + or - 6.47 g L.sup.-1) was obtained in the F/2 medium with 12L: 12D treatment, while the lowest (18.99 + or - 0.78 g L.sup.-1) was in the M 12L: 12D group. Regardless of the culture conditions, the lipids were mainly composed of the C16:0 and C18 fatty acids. The use of molasses as a culture medium produced the highest amount of C18:l, regardless of the light regime. Molasses promoted the highest production of fatty acids methyl esters. Depending on the culture medium, D. salina cells showed different percentages of saturated (SFA), monounsaturated (MFA), and polyunsaturated (PUFA) fatty acids. The highest amount of saturated fatty acids was obtained in F/2 12L:12D. The highest amount of polyunsaturated fatty acids was presented in the mixotrophic culture (molasses and light). The cultures grown with molasses were rich in monounsaturated fatty acids. An inexpensive industrial by-product, Cane molasses could be a low-cost feedstock for biodiesel in cultivating D. salina.
The effect of stocking density and water exchange was evaluated on growth performance of
Litopenaeus vannamei
postlarvae (PL), reared in a biofloc-based system at the nursery level and exposed to ...short-term low-high salinity stress. A bioassay was conducted with four treatments in triplicate:
T
1
= 8500 postlarvae/m
3
without water exchange,
T
2
= 16,500 postlarvae/m
3
without water exchange,
T
3
= 8500 postlarvae/m
3
with 50% water exchange per week, and
T
4
= 16,500 postlarvae/m
3
with 50% water exchange per week. At 0 (PL′22), 15 (PL′37), 30 (PL′52), and 45 (PL′67) days of culture, a group of shrimp from each treatment was exposed to acute stress by low (27 to 2‰) and high (27 to 60‰) salinity. After 45 days, the water exchange rate and water exchange rate × stocking density interaction affected shrimp survival, but shrimp growth was affected only by stocking density. The mean weight of shrimp in the treatments with the lowest stocking density was higher than that with the highest stocking density, independently from the water exchange rate. In the salinity stress tests, shrimp survival was affected by the interaction between the salinity stress tests and treatments. Generally, shrimp showed a greater tolerance when subjected to low salinity (27 to 2‰). In the culture with biofloc at the nursery level, it was confirmed that
L. vannamei
shrimp improve their tolerance to a sudden low salinity endpoint; a directly proportional relationship of survival with ontogenetic development in low and high salinity was determined.
The effects of reducing feeding rate and molasses on water quality, growth, and gene expression of Litopenaeus vannamei were evaluated in a super intensive system with zero water exchange. A bioassay ...of 35 days (0,75 ± 0,22 g, 36 shrimp tank-1, 450 shrimp m-3) with treatments in triplicate was performed: I) 100% commercial feed (control group) with water exchange; II) 100% commercial feed without water exchange; III) 100% commercial feed + Bacillus licheniformis BCR 4-3 + molasses without water exchange; IV) 90% commercial feed + B. licheniformis BCR 4-3 + molasses without water exchange, and V) 80% commercial feed + B. licheniformis BCR 4-3 + molasses without water exchange. Shrimp survival, weight, nitrogenous wastes, settleable solids (SS), and the relative expression (RT-qPCR) of stress and digestive genes were determined. Shrimp survival was 100% in all treatments. The reduced diet, bioflocs, and bacilli did not affect shrimp growth. The culture conditions reduced nitrogenous wastes and modulated mRNA expression of trypsin, chymotrypsin, and heat shock protein 70. Reduced feed ration can help to maintain water quality and lower costs in intensive shrimp cultures with bioflocs.
The aim of this study was to investigate the effects of organic (molasses) and inorganic (Nutrilake®) fertilization on plankton, water quality, and shrimp Litopenaeus vannamei performance reared in ...zero-discharge tanks and ponds. The findings showed that in tanks, the organic fertilization induced highest survival and production, and low total ammonia-N concentration; however, this effect was not observed in the ponds. In both tanks and ponds, the inorganic fertilization increased nitrogen levels. The phytoplankton abundance increased in both tanks/ponds with the fertilization treatments. Shrimp production in the tanks and ponds fertilized almost doubled compared with unfertilized treatments.
The aim of this study was to investigate the effects of organic (molasses) and inorganic (Nutrilake® ) fertilization on plankton, water quality, and shrimp Litopenaeus vannamei performance reared in ...zero-discharge tanks and ponds. The findings showed that in tanks, the organic fertilization induced highest survival and production, and low total ammonia-N concentration; however, this effect was not observed in the ponds. In both tanks and ponds, the inorganic fertilization increased nitrogen levels. The phytoplankton abundance increased in both tanks/ponds with the fertilization treatments. Shrimp production in the tanks and ponds fertilized almost doubled compared with unfertilized treatments.
A search is performed for the central exclusive production of pairs of charmonia produced in proton-proton collisions. Using data corresponding to an integrated luminosity of collected at ...centre-of-mass energies of 7 and 8 TeV, and pairs are observed, which have been produced in the absence of any other activity inside the LHCb acceptance that is sensitive to charged particles in the pseudorapidity ranges and . Searches are also performed for pairs of P-wave charmonia and limits are set on their production. The cross-sections for these processes, where the dimeson system has a rapidity between 2.0 and 4.5, are measured to be where the upper limits are set at the 90% confidence level. The measured and cross-sections are consistent with theoretical expectations.
During the COVID-19 crisis it was necessary to generate a specific care network and reconvert operating rooms to attend emergency and high-acuity patients undergoing complex surgery. The aim of this ...study is to classify postoperative complications and mortality and to assess the impact that the COVID-19 pandemic may have had on the results.
this is a non-inferiority retrospective observational study. Two different groups of surgical patients were created: Pre-pandemic COVID and Pandemic COVID. Severity of illness was rated according to the Diagnosis-related Groups (DRG) score. Comparisons were made between groups and between DRG severity score-matched samples. Non-inferiority was set at up to 10 % difference for grade III to V complications according to the Clavien-Dindo classification, and up to 2 % difference in mortality.
A total of 1649 patients in the PreCOVID group and 763 patients in the COVID group were analysed; 371 patients were matched for DRG severity score 3-4 (236 preCOVID and 135 COVID). No differences were found in relation to re-operation (22.5 % vs. 21.5 %) or late admission to critical care unit (5.1 % vs. 4.5 %). Clavien grade III to V complications occurred in 107 patients (45.3 %) in the PreCOVID group and in 56 patients (41.5 %) in the COVID group, and mortality was 12.7 % and 12.6 %, respectively. During the pandemic, 3 % of patients tested positive for Covid-19 on PCR: 12 patients undergoing elective surgery and 11 emergency surgery; there were 5 deaths, 3 of which were due to respiratory failure following Covid-19-induced pneumonia.
Although this study has some limitations, it has shown the non-inferiority of surgical outcomes during the COVID pandemic, and indicates that resuming elective surgery is safe.
Clinicaltrials.gov identifier: NCT04780594 .
A vital goal of cleaner production involves developing agricultural production systems capable of ensuring sufficient yields of highly necessary foods to meet the increasing needs of the global ...population while minimizing the associated economic and ecological costs. Integrated agri-aquaculture systems (IAAS) offer a number of advantages for sustainable agriculture, including water reutilization, discharge mitigation, and increased profitability by leveraging the symbiotic relationship between organic waste, bacterial mineralization, and plant filtration. The aim of this study was to assess the production of two food items of global socio-economic importance cultivated at different salinities: Pacific white shrimp (Penaeus vannamei) and tomatoes (Solanum lycopersicum L.) grafted to salinity tolerant wild tomatoes. Pacific white shrimp were cultured at a density of 125 organisms/m3 and tomatoes at a density of 3 plants/m. The shrimp growth test consisted of three salinity levels: 2, 4, and 6 g/L. The corresponding tomato salinity treatments were conducted using shrimp water effluents; Steiner’s universal nutrient solution (SNS) was used for the control treatment. The experimental period lasted 175 days. The highest tomato production (77.46 t/ha) was attained with SNS, with no significant difference from the salinity of 2 g/L. Shrimp final mean weight, survival, and production were higher at the 6 g/L salinity; and all the other zootechnical parameters decreased with lower salinity. When compared with the hydroponic system using a cost-benefit analysis (CBA), the production costs associated with the IAAS were lower primarily because of the reduced (or null) costs of fertilizer, and irrigation water. When grafted plants were used, the salinity tolerance of the commercial hybrid increased and shrimp could be cultured at appropriate salinity to facilitate osmoregulation. Chemical fertilization requirements were reduced and acceptable yields were obtained for the tomato crop by grafting to salinity-tolerant rootstocks.
•Saline-tolerant Guasave wild tomato was 100% resilient to 9 g/L salinity.•Shrimp and grafted tomato in 4 g/L salinity were stress tolerant and productive.•Salinity levels >4 g/L increased blossom-end rot by 40% even with grafted tomato.•Aquaponics yield budgets must consider costs of biofiltration and nutrients recovery.•Waste discharge and water supply concerns may be mitigated with aquaponics.
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