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Sex Morality Lecture
No full textThe title at the top of the page is "sex morality lecture" from the National Lutheran Council. There are three numbered items listing sacredness, abundant life, and ambassadors of America
Immunomodulation with Probiotics Against Aeromonas veronii in Grass Carp (Ctenopharyngodon idellus)
Get PDFAeromonas comprisea wide range of opportunistic bacteria that cause septicemia (blood poisoning)in fish.Withexpandingaquaculture, myriad methods have been used to combat these pathologiesincludingprobiotics and plant extracts which canpotentiallyaddress these diseases without harmingthe environment. Inthis study, four strains of opportunistic pathogens were isolated from diseased fish, thenmolecular identification of 16SrDNA was performed. Results identifiedthe four strains asAeromonas veronii, Shewanella sp., Bacillus cereus, and Aeromonas salmonicida. Experimental trialsrevealed that A.veroniiwas the primary strain. Multiple virulence-related factors were discovered, includingaerolysin (Aer), cytotoxic enterotoxin (Act), and the outer membrane protein (OmpAII).Thesewere foundonly in A.veronii. LC50 in grass carp was 3.6×104CFU/mLover 96 h, whereas the safe concentration was 9.11×103CFU/mL.Grass carp were challenged with 3 differentconcentrations of A.veronii. Following a 48h incubation period they were treated for 24 h, 48 h, and 72 h with 8.1×106CFU/mLconcentrations.The expression ofInterleukin-8(IL-8)andTumor Necrosis Factor-α(TNF-α)was up-regulated in the kidney, liver, spleen, and heart using qRT-PCR. Simultaneously, enzyme activity involving Pyruvate Kinase(PK),Alkaline Phosphatase(AKP), Alanine aminotransferase (ALT),Succinate Dehydrogenase (SDH), and Lysozyme (Lsz)inserum and liver tissues was significantly up-regulated.We found that probiotics enhancedgrowth of grass carp, improvedhealth status,and was beneficial in reducing the prevalence of this disease. Subsequent to feeding mixed probiotics,IL-8 and TNF-α geneexpression was significantly lower (p>0.05)than inthe infected group,at 16 and 31 days. Expression of these genes in the liver, spleen, and intestines of healthy grass carp fed probiotics wassignificantly up-regulated in contrast to grass carp fed a basal diet (p<0.05).Our results suggestthat use of probiotics as immune stimulator may improve the control of fish diseases in aquaculture
Effect of Dietary Supplementation of Glycyrrhetinic Acid and Tea Polyphenols on Depuration of 2-methylisoborneol from Blunt Snout Bream, Megalobrama amblycephala
Get PDFAbstract_Off-flavor is a serious issue in cultured fish. It affects marketability and texture of fish and
causes great economic losses in the aquaculture industry. Holding fish in a clean-water
environment for some time is an effective method to depurate them although it involves
weight loss. This study investigates the potential effects of dietary supplementation of
glycyrrhetinic acid (GA) and tea polyphenols (TP) on the depuration of the strong odors of 2-
methylisoborneol (MIB) from blunt snout bream, Megalobrama amblycephala. 560 fish, initial
average weight of 48.75±0.48 g were distributed into 28 tanks at a rate of 20 fish per tank.
Three diets, namely the control diet, a GA supplemented diet (0.3 g/kg), and a (TP)
supplemented diet (0.3 g/kg) were used in this study. The control diet was randomly assigned
to 20 tanks, 4 tanks with clean water (control), or with water containing 1μg/L MIB. During the
first 28-day the fish in each treatment were hand-fed to apparent satiation three times daily.
In the second phase (29-42 day), the control, GA, and TP treatments were divided into four
groups: MIB, low density (LD), high density (HD), and dynamic sampling (DS) with twenty fish
in DS, and fifteen fish in the others. Fish in LD, HD, and DS in all treatments were starved in
clean water. Fish in the DS treatment were sampled at 0, 24, 48, 72 hours, at 7 and 14 days.
No differences were observed in body weights between groups within the 28-day feeding trial
(P>0.05). Fish in GA, LD, and HD groups had significantly lower hepatosomatic index (HSI)
and intraperitoneal fat ratios (IPF) than the control, MIB, and TP groups (P<0.05). After 28
and 42 days, fish in the MIB group had higher MIB concentrations than the other groups
(P<0.05). Scores of sensory characteristics were similar, with no statistical differences
between the control, GA, and TP groups (P>0.05). MIB content decreased significantly in
relation to longer depuration times (P<0.05). Fish weight in LD and HD treatments declined by
10% and 12% respectively after 14-day fasting. In conclusion, clean water depuration for
fourteen days is an effective method to purge off-flavored flesh although it involves weight loss
and dietary supplementation of GA and TP which also depurate MIB from flesh of Megalobrama
amblycephala
Antifungal Activity of Magnolia officinalis Derived Magnolol and Honokiol on Membrane Disruption of Saprolegnia parasitica
Get PDFSaprolegniosis is an infectious disease caused by Saprolegnia sp. It may cause serious losses in fish farms and hatcheries in many countries. In previous research, Magnolia officinalis has been found to initiate the death of Saprolegnia sp. Magnolol and honokiol, two active substances in M. officinalis, may be responsible for the antifungal effects on Saprolegnia sp. The present study centered on the anti-fungal activity and mechanism of magnolol and honokiol on Saprolegnia parasitica. Results revealed that magnolol and honokiol displayed effective anti-fungal activity on S. parasitica, which caused their mass mortality. More intuitive research has shown that magnolol and honokiol have evolved mechanisms that can destroy the cell membranes of S. parasitica, and cause exosmosis of their cytoplasmic saccharides and proteins, and cause mortality. Magnolol and honokiol exhibited minimum inhibitory concentration values of 976.6 ug/mL and 587.4 ug/mL concentrations, respectively, and the minimum inhibitory time of both was 2 hours. This study provides a clearer understanding of the function of M. officinalis against Saprolegnia sp
Combined Effects of Dietary Phosphorus Level and Polyculture on Fish Production, Water Quality, and Plankton Composition, in Intensive Culture of Crucian Carp
Get PDFThe combined effects of dietary phosphorus (P) levels and co-culture of silver and bighead carp on fish production, water quality, and the planktonic community in intensive culture of crucian carp (Carassius carassius) were studied in this enclosure experiment. There were four treatments with three replicates each: crucian carp (50 fish) fed with low (8.7 g/ kg) or high phosphorous (13.5 g/ kg) diets (L1 and H1), and polyculture (50 crucian carp + 10 silver carp + 10 bighead carp) fed with low or high-phosphorus diets (L3 and H3). Results suggested that polyculture with filter feeders suppresses crucian carp growth, especially when supplied with low phosphorus diet. Polyculture significantly enhanced the total fish production when crucian carp were fed a diet with high P levels. Dietary P level and polyculture with silver and bighead carp did not affect dissolved oxygen (DO), pH, water transparency, NH4+-N, total nitrogen, or any form of phosphorus (p < 0.05), while the presence of filter feeders significantly suppressed plankton. The present experiment suggested that silver carp is more suitable for polyculture with crucian carp, and a higher P level is needed to support plankton and reduce competition with crucian carp
Effect of Dietary Carbohydrate Levels on the Growth and Liver Function of Carp Cyprinus carpio
Get PDFThis experiment was conducted to study the effects of carbohydrate levels on the growth and liver function of Tianjin carp, Cyprinus carpio (mean body weight, 60.82 ± 0.38 g). Three diets, including 30% protein and 5.5% fat (dry matter) and 0, 15, or 30% corn starch (carbohydrate source) were provided to control, low carbohydrate, or high carbohydrate treatment groups, respectively. Weight gain, specific growth rate, hepatopancreas somatic index, and liver glycogen content were significantly higher in fish fed the 30% corn starch diet than fish fed 0% corn starch (P<0.05) but did not differ between the other two treatment groups. Protein efficiency ratio increased significantly as corn starch level increased (P<0.05), but feed conversion ratio showed the opposite trend (P<0.05). Glutamic pyruvic transaminase activity in the serum significantly increased with increasing corn starch levels (P<0.05), but total protein (decreasing trend) and glutamic-oxaloacetic transaminase (increasing trend) did not differ among dietary treatments. Histomorphological analysis of hepatopancreas sections showed that fish fed 15% or 30% corn starch diets presented mild hydropic degeneration and fatty degeneration or severe fatty degeneration, respectively. In summary, although carbohydrates promote carp growth, they enhance glycogen and fat accumulation in the hepatopancreas, reducing its function
Response of Antioxidant Enzymes and Digestive Enzymes to Temperature Stress in Lates Calcarifer Larvae
Get PDFAcute temperature stress in 15-day post-hatch (DPH) Lates calcarifer larvae was studied using the semi-static bioassay method to understand the physical response of fish larvae to low temperature. In this study, 20oC, 22oC, 24oC, and 26oC were tested and 28oC was the control. Antioxidant enzyme activity including superoxide dismutase (SOD), peroxidase (POD), catalase, acid phosphatase (ACP), glutathione peroxidase (GSH-Px) and digestive enzymes including lipase, amylase, trypsin, pepsin were used as the physical indicators. SOD activities were elevated to scavenge excess reactive oxygen species (ROS) after exposure to lower temperatures, and their activities increased dramatically in relation to the increasing residue time. POD enzyme activity maintained a low level in the early stage of cold exposure and increased to a high level in relation to exposure time. Catalase, GSH-Px, and ACP activities were elevated in fish after exposure to lower temperatures compared to those in fish maintained at 28oC. Lipase activity decreased after exposure to lower temperatures and modestly elevated over time. The highest amylase activity was observed in the control group. However, trypsin and pepsin activity was elevated with the decrease of environmental temperature.
Our results indicate that lower temperature significantly affects activity of antioxidant enzymes and digestive enzymes in barramundi larvae. Barramundi larvae exhibited a certain tolerance of low temperature for a short period. Results from the present study will improve our understanding of the physical response of warm water fish to low temperatures and can therefore guide hatchery practices for Lates calcarifer
Cyclopamine Induced Expression of Immune-related Genes in Rainbow trout (Oncorhynchus mykiss) Head Kidney Leukocytes
Get PDFThis study investigated the effect of cyclopamine, a hedgehog signaling inhibitor, on immune-related gene expression in rainbow trout head kidney leukocytes in vitro. At 1h sampling time COX 2, IFN-2, TNF-α, C3, MHC-II, Il-1β, IL-12, IL-10, and IL-6 increased significantly in groups exposed to cyclopamine at 30 μg/ml. However, in groups exposed to 10 and 20 μg/ml cyclopamine, the expression of these genes decreased significantly. At 4h sampling time, levels of COX-2, IFN-1, IFN-2, TNF-α, TGF-β, IgT, and MHC-II in groups exposed to 20 μg/ml cyclopamine increased. At 8h sampling time, COX2, IFN-Reg, and TNF-α expression in groups exposed to 10 and 30 μg/ml cyclopamine increased significantly compared to those in the controls. Conversely the expression decreased significantly for almost all other genes. At 12h sampling time, almost all genes increased significantly in groups exposed to 10 μg/ml cyclopamine compared to those in the controls. Notably, after 24h, the gene expression in all groups significantly decreased compared to the controls. Our results suggest that the activation of cyclopamine can be a useful tool for the examination of immune-related gene expression in the rainbow trout
