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Free fatty acids have long been used as dietary supplements in aquaculture, but the application of monoglycerides has increased interest in more recent times. The study aimed to investigate the effects of dietary short- and medium-chain fatty acid monoglyceride and cinnamaldehyde (SMMG) on the growth performance, survival, immune responses, and tolerance to hypoxic stress of Pacific white shrimp (Litopenaeus vannamei). In Experiment 1, shrimp post-larvae were divided into 4 groups with 6 replicates and fed with diets supplemented with 0 (control), 0.3, 0.4, and 0.5% diet for 30 days. The final body weight and survival rate were determined. In Experiment 2, the juvenile shrimp from Experiment 1 were subjected to hypoxic stress conditions (dissolved oxygen level 2–2.5 mg/L) for 14 days, then the specific growth rate (SGR), survival rate, intestinal Vibrio spp. count, immune responses, and histopathological change of the hepatopancreas were analyzed. Following the 30-day feeding trial, the results revealed that the final body weight and survival of the 0.3–0.5% SMMG groups (2.81–3.06 g and 74.00–84.33%, respectively) were significantly higher than the control shrimp (1.96 g and 68.33%, respectively). In the hypoxic stress experiment, the survival rates of shrimp fed 0.4–0.5% SMMG (71.67–80.00%) were significantly higher than the control (51.67%). Although the SGR were not affected by SMMG supplementation, all immune parameters evaluated were significantly enhanced, and the intestinal Vibrio spp. counts were significantly decreased in the 0.4–0.5% SMMG-fed shrimp; the histopathological structure of the hepatopancreas was also improved in these shrimp compared to the control. Our findings indicated that SMMG as a feed additive has beneficial effects in improving shrimp health and increasing tolerance to hypoxic conditions. [ABSTRACT FROM AUTHOR]

Toltrazuril (TZR) is currently the only registered chemotherapeutic drug in the European Union for the treatment of Cystoisospora suis. This study investigated the comparative pharmacokinetics and tissue concentration‐time profiles of TZR and its active metabolite, toltrazuril sulfone (TZR‐SO2), after oral (per os, p.o.) and intramuscular (i.m.) administration to suckling piglets. Following a single administration of TZR orally at 50 mg/piglet or intramuscularly at 45 mg/piglet, higher concentrations of TZR and TZR‐SO2 were observed in all three investigated tissues after p.o. administration. The mean TZR concentration in serum peaked at 14 μg/mL (34.03 h) and 5.36 μg/mL (120 h), while TZR‐SO2 peaked at 14.12 μg/mL (246 h) and 9.92 μg/mL (330 h) after p.o. and i.m. administration, respectively. TZR was undetectable in the liver after p.o. administration (18 days) and in the jejunum (24 days) after i.m. injection, while TZR‐SO2 was still detectable in all three tissues after 36 days regardless of administration routes. This study showed that p.o. formulation exhibited faster absorption and higher serum/tissue TZR/TZR‐SO2 concentrations than i.m. formulation. Both formulations generated sufficient therapeutic concentrations in the serum and jejunum, and sustained enough time to protect against Cystoisospora suis infection in the piglets. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the effect of tributyrin on the growth performance, survival, hypoxia tolerance, and nutrient digestibility of Pacific white shrimp fed 25% and 50% soybean meal (SBM) diets. Six experimental diets were formulated: (1) 25% SBM without tributyrin; (2) 25% SBM with 0.05% tributyrin; (3) 25% SBM with 0.1% tributyrin; (4) 50% SBM without tributyrin; (5) 50% SBM with 0.05% tributyrin; and (6) 50% SBM with 0.1% tributyrin. The shrimp were fed the experimental diets daily for 10 weeks. Tributyrin supplementation at 0.1% diet significantly improved the weight gain of shrimp that fed 25% SBM but not the other groups. Nevertheless, shrimp that fed tributyrin had significant improvement in survival rate at both SBM levels. Significant reductions in Vibrio spp. counts in the hepatopancreas and intestine were also evident in all tributyrin‐fed groups. In addition, 0.1% tributyrin in both SBM levels significantly enhanced the shrimp tolerance to hypoxia. Lastly, the digestibilities were generally unaffected by the tributyrin except only for the lipid digestibility of the 0.1% tributyrin in 25% SBM group, which showed a significant increase. Overall, tributyrin was proven beneficial for the shrimp's health, especially for those fed diet with a moderate level of SBM (25%). [ABSTRACT FROM AUTHOR]

Drug behavior in the bodies of fish is largely influenced by the water temperature. Antimicrobial drugs are needed for the control of bacterial outbreaks in farmed fish including Asian seabass (Lates calcarifer). However, little is known about the temperature effect on appropriate drug uses in this species. The purpose of this study was to investigate the differences in pharmacokinetics (PK), optimal dosages, tissue depletion, and withdrawal time (WDT) of florfenicol (FF) in Asian seabass reared at 25 and 30 °C. In the PK study, the fish were administered with a single oral dose of 10 mg/kg FF. The optimal dosing regimen was determined by the pharmacokinetic-pharmacodynamic (PK-PD) approach. In the tissue depletion and WDT study, FF was administered at the optimal dosages once daily for 5 days and the WDT was determined by linear regression analysis based on the sum of FF and its metabolite florfenicol amine (FFA) in the muscle/skin. When the temperature was increased from 25 to 30 °C, the elimination half-life of FF was significantly decreased from 11.0 to 7.2 h. While the other PK parameters were not changed significantly, the calculated optimal dosages for the target minimum inhibitory concentration (MIC) of 2 µg/mL were 10.9 and 22.0 mg/kg/day, respectively for 25 and 30 °C. The sum of FF + FFA is a preferable marker residue for WDT determination because differential FF metabolism was observed at different temperatures. The depletion half-life of the muscle/skin was shortened from 41.1 to 32.4 h by the 5 °C temperature increase. Despite different absolute amounts of FF given between the two temperature levels, the WDTs were very similar at 6-7 days. Thus, it appears that a single temperature-independent WDT can potentially be assigned when the drug was applied at the optimal dosage. [ABSTRACT FROM AUTHOR]

Asian seabass (Lates calcarifer) is an economically important fish in Asian and Australian markets, but few pharmacokinetic (PK) data of antimicrobial drugs in this species is available. The present study investigated the PK behaviour of florfenicol (FF) through medicated feed in Asian seabass cultured at 25°C. The serum and muscle/skin concentrations of FF and its metabolite florfenicol amine (FFA) were determined by the HPLC‐FLD method and analysed by one‐compartmental model. The optimal dosages were determined by pharmacokinetic‐pharmacodynamic (PK‐PD) approach and the linear regression analysis was used to determine the withdrawal time (WDT). The PK study following a single oral administration of 15 mg/kg FF via medicated feed revealed that the absorption half‐life (t1/2Ka), elimination half‐life (t1/2K), peak concentration (Cmax), area under the concentration‐time curve (AUC), volume of distribution (Vd/F) and clearance (CL/F) were 1.47 h, 8.07 h, 8.61 μg/ml, 146.41 h·μg/ml, 1.19 L/kg and 0.102 L/kg/h, respectively. The muscle/skin concentration‐time profile was similar to that of the serum, suggesting well distribution but only a small fraction of FF was metabolized to FFA. The optimal dosage for a minimum inhibitory concentration of 2 μg/ml was calculated as 13.38 mg/kg/day. The appropriate WDT after multiple oral medications with 15 mg/kg FF once daily for 7 days was determined as 8 days. Information obtained from the current study can potentially be applied for the treatment of bacterial diseases in farming Asian seabass. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of the solvent used in microalgae extraction on the total phenolic content (TPC), total flavonoid content (TFC), antioxidant, and anti-carbohydratehydrolyzing enzyme activities of the crude extracts. Algal biomass of Chlorella vulgaris and Spirulina platensis was extracted by different types of solvent, namely n-hexane, ethanol, methanol, and distilled water. Additionally, the correlations of TPC and TFC with antioxidant activity as well as anti-diabetic activity (anti-α-amylase and anti-α-glucosidase) were investigated. Results demonstrated that C. vulgaris and S. platensis methanolic extracts had the highest TPC, with values of 40.62±4.13 and 64.38±7.39 mg GAEg-1 (mg of gallic acid equivalent per gram extract), respectively. These extracts also showed the greatest antioxidant activity, with IC50 values for DPPH (2,2-diphenyl-1-picrylhydrazyl) of 117.62±4.46 and 97.89±4.64 μgmL-1, respectively, and ABTS (2,2-azinobis [3-ethylbenzothiazoline-6-sulfonic acid]) of 102.52±2.50 and 46.21±0.88 μgmL-1, respectively. Furthermore, they strongly inhibited α-amylase activity (IC50 of 262.97±9.61 and 275.46±12.44 μgmL-1) and α-glucosidase activity (IC50 of 207.09± 6.97 and 169.01±3.16 μgmL-1). TPC was positively and significantly correlated with antioxidant and α-glucosidase inhibition activities. Meanwhile, only α-amylase inhibitory activity had a significant positive correlation with TFC. Therefore, crude methanolic extracts of C. vulgaris and S. platensis might be potential sources of natural antioxidants and anti-diabetic dietary supplements. [ABSTRACT FROM AUTHOR]

We evaluated the advantages of all-male giant freshwater prawn (Macrobrachium rosenbergii) culture over traditional mixed-sex and all-female systems in the aspects of growth performance, production yield, and profitability. The prawn post-larvae were reared in a nursery pond for 43 days until the male sexual characteristics (gonopore complex) could be distinguished externally, then they were sexed and transferred to monosex grow-out ponds (two ponds per sex) and cultured for another 140 days. The prawn post-larvae in the mixed-sex group were reared for 60 days in the nursery phase and 165 days in the grow-out phase. At harvest, the male prawns from the all-male group had higher body weight (93.02 g), average daily growth (0.66 g.day-1), and specific growth rate (3.41 %.day-1), compared to the males in the mixed-sex system (69.38 g, 0.41 g.day-1, and 2.56 %.day-1, respectively). The proportion of an unfavorable "small male" morphotype was reduced from 20.11 % in the mixed-sex culture to 4.67 % in the all-male system, whereas that of a desirable "orange claw" morphotype was increased from 38.59 to 61.33 %. Ultimately, the production yield of the all-male group was 2,076.6 kg·ha-1, whereas that of the mixed-sex system was 1,273.8 kg.ha-1. The cost-benefit analysis revealed that the former was 155.78 % more profitable than the latter. The all-female group showed the best survival rate and feed conversion ratio, yet it was the least profitable system. In conclusion, the all-male culture was the most productive and profitable system of giant freshwater prawn farming. [ABSTRACT FROM AUTHOR]

BACKGROUND The flavor and quality of tea are widely believed to be associated with the pot in which the tea is made. However, this claim is mostly by experiences and lacks solid support from scientific evidence. The current study investigated and compared the chemical compositions of oolong tea made with six different teapot materials, namely Zisha, Zhuni, stainless steel, ceramic, glass and plastic. RESULTS For each tea sample, polyphenols and caffeine were examined by HPLC-UV, volatile compounds by GC/MS, amino acids by LC/MS and minerals by ICP-MS. The results suggested that tea infusions from Zisha and Zhuni pots contain higher levels of EGC, EGCG and total catechins and less caffeine than those from ceramic, glass and plastic pots and tend to have the lowest total mineral contents, potassium and volatile compounds in tea soup. The statistical differences were not all significant among Zisha, Zhuni and stainless steel pots. CONCLUSION Based on the overall chemical composition of the tea infusion, Yixing clay pots (Zisha and Zhuni) produce tea infusions that are presumably less bitter and more fragrant and tend to contain more healthful compounds than tea infusions from other pots. The results could partially explain why Yixing clay pots are among the most popular teapots. The beneficial effects of long-term repeated use of these teapots warrants further study. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]