• Applied Microscopy
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• v.32 no.3
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• pp.205-211
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• 2002

The purpose of this study was to evaluate the effect the lead toxicity of chitosan on the rats. A healthy male of Wistar rat was used for experiment. The lead acetate (30 mg/kg, Pb) was injected two times per a week into the abdomen. 0.1% chitosan solution (1 mg/ml) was supplied by feeding ad libitum. After 4 or 8 weeks, we was observed kidney by electron microscope. The experimental groups were divided into two groups. Group 1 was control group which was not treated with chitosan solution after contaminatation of lead acetate. Group 2 was experimental group which was treated with chitosan solution after contamination of lead acetate. All groups were used to 10 rats. The results were as follow: On the proximal convoluted tubules of the group with only Pb, the number of microvillis were decreased and the number of lysosomes were increased on the cytoplasm. The mitochondria and rough endoplasmic reticulum were extended and ribosomes dropped from the rough endoplasmic reticulum. On the proximal convoluted tubules of the group with Pb-chitosan, the shapes and number of microvilli were not changed and the number of lysosomes were decreased. The shapes of mitochondria and endoplasmic reticulum observed not changes. We concluded that chitosan has effect on reducing toxicity of lead in the rat kidney.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.521-534
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• 2020

Paralytic shellfish poisoning (PSP) occurs when saxitoxin (STX), which is produced by harmful algae (dinoflagellates) and then accumulated in bivalve shellfish by filter-feeding, is consumed by humans. With recent advances in analysis technology, it has been reported that dinoflagellates also produce a variety of analogues such as the gonyautoxin (GTX) group and the N-sulfo-carbamoyl toxin (C toxin) group, in addition to STX. Accordingly, CODEX and the EFSA are stepping forward to manage STX and analogues as STX groups requiring safety management. In Korea, the occurrence of dinoflagellates producing STX analogues has already been reported, and contamination of analogues (GTX group, C toxin group) in live mussels has also been reported. In this study, in order to provide the basis for systematic monitoring and safety management of STX and analogues, their physicochemical characteristics, occurrence of dinoflagellates, toxicity and toxic equivalency factor, analytical method and occurrence were widely reviewed. This review is expected to contribute to strengthening the safety management of STX and its analogues.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.435-445
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• 2008

Due to internal feeding behavior, the oriental tobacco budworm, Helicoverpa assulta ($Guen\acute{e}e$), infesting hot pepper has been regarded to be effectively controlled by targeting egg and neonate larval stages just before entering the fruits. This study aimed to develop an efficient biological control method focusing on these susceptible stages of H. assulta. An egg parasitoid wasp, Trichogramma evanescens Westwood, was confirmed to parasitize the eggs of H. assulta. A mixture of Gram-positive soil bacterium, Bacillus thuringiensis subsp. kurstaki, and Gram-negative entomopathogenic bacterium, Xenorhabdus nematophila ANU101, could effectively kill neonate larvae of H. assulta. A sex pheromone trap monitored the occurrence of field H. assulta adults. The microbial insecticide mixture was proved to give no detrimental effects on immature development and adult survival of the wasp by both feeding and contact toxicity tests. A combined treatment of egg parasitoid and microbial pesticide was applied to hot pepper fields infested by H. assulta. The mixture treatment of both biological control agents significantly decreased the fruit damage, which was comparable to the chemical insecticide treatment, though either single biological control agent did not show any significant control efficacy. This study also provides morphological and genetic characters of T. evanescens.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.4
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• pp.496-500
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• 2001

In vitro and in vivo experiments were carried out to evaluate the nutritive value of three tropical browse species as assessed by DM and CP digestibility, and NDF and ADF degradability with incubation times (T) of 6, 12, 24 and 48h. During the in vivo digestibility experiment three male castrated sheep (age 16 - 25 months) with a mean liveweight of $11.5{\pm}0.9kg$ were placed in individual metabolism stalls and were allocated to one of the three browse species in a $3{\times}3$ Latin square design. The browse species were all leguminous and consisted of: Acacia sieberina (A. sieberina), Ficus polita (F. polita), and Ficus sycomorus (F. sycomorus). The mean DM and CP contents of F. polita were higher than for A. sieberina and F. sycomorus (p<0.05). In contrast the NDF and ADF contents of F. sycomorus were higher compared to the other species examined (p<0.05). The in vitro DM and CP digestibility, and NDF and ADF degradability observed at different stages of incubation were higher in F. polita followed by A. sieberina and F. sycomorus. The DM and CP digestibility at 48 h incubation were 72.92, 74.84 and 53.52% and 77.38, 77.68 and 63.64% for A. seiberina, F. polita and F. sycomorus, respectively. This shows that F. polita contains more soluble materials which ruminant can benefit from and hence has more feeding value. The fermentation of F. sycomorus was slower for all the nutrients evaluated due to the presence of more fibre. Similarly, higher in vivo digestibility coefficient of DM, CP, NDF, ADF and hemicellulose were observed for F. polita reflecting its higher values of CP, ether extract (EE) and hemicellulose associated with lower values of NDF and ADF. Higher DMI and daily gain were recorded in sheep during feeding of F. polita compared to the other species evaluated. The digestibility of all the nutrients examined were higher in the in vivo than in the in vitro trial except for CP and DM. Sheep showed no visual signs of toxicity throughout the study periods. These results showed A. seiberina, F. polita and F. sycomorus can sustain sheep on a maintenance diet and could as well be used as a supplementary feed to low producing animals during the tropical dry season. Further research is needed to ascertain the viability of using these browse species on a long-term basis.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.192-200
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• 1998

This study was carried out to evaluate the effect of feeding higher protein feeds with lesser amount, but feeding the constant total protein input for all treatments, on water quality and nitrite toxicity in channel catfish ponds. There was no significant difference in survival rate among treatments $(P>0.05)$. Specific growth rate (SGR) for Treatment 1$(28\%\;protein\;and\;100\%\;of\;satiation)$ was significantly higher $(P>0.05)$ than for Treatment 3$(36\%\;protein\;and\;87.5\%\;of\;satiation)$, but not significantly higher than for Treatment 2 $(32\%\;protein\;and\;77.8\%\;of\;satiation)$ at constant digestible energy (DE), 3.08kcal/g (treatments 1, 2 and 3). At constant DE/P (treatments 4, 2 and 5), no significant difference in SGR was observed among treatments. Feed conversion ratio (FCR) slightly improved or improved as dietary protein level increased from $28\%$ to $32\%$ and feed allowance decreased by $12.5\%$, but did not improve as dietary protein level increased from $32\%$ to $36\%$ and feed allowance decreased by $22.2\%$, at constant DE and constant DE/P. There was no significant difference in water quality variables, such as total ammonia nitrogen (TAN), nitrite, chlorophyll a, soluble phosphorous concentrations among treatments, but significant difference in water quality variables over time as amount of feed fed increased $(P<0.0001)$. There was a trend toward increase in TAN and nitrite over time. A strong linear regression was observed between mean total ammonia nitrogen and nitrite for all treatments Y (Nitrite) =$0.04\times (TAN)+0.01$, $R_2=0.89$. Methemoglobin percent in the blood of catifish was not significantly different among treatments. And its mean value was $7.5\%$, which was relatively low, so that it was not serious problem in catfish production pond under these experiment conditions. There was the stronger linear regression between the percentage of Methemoglobin and the molar ratio of nitrite to chloride rather than nitrite alone: $Y\;(Methemoglobin\;\%)\;=\;58.45\;\times\;(NO^{2-}/Cl^-)\;+\;0.41,\;R^2=0.60$. These results indicate that deterioration of water quality has no strong impact on poor weight gain for $36\%$ dietary protein in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.577-583
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• 2011

In 2007, pet food contaminated with melamine caused hundreds of dogs and cats to develop renal failure all over the world. In 2008, over 294,000 infants consumed infant formula and developed kidney stones in China. Further investigation revealed that fish feed also contained melamine; this raised concerns about melamine residues in edible fish tissues, which could have caused the urinary tract stone epidemic. In Korea, catfish fed with assorted feed that included cuttlefish organs that contained melamine developed whitening syndrome and fell dead in some populations in 2008. This event raised suspicions about the toxicity of melamine and all feeds containing melamine were immediately recalled. In this study, we investigated the rates of melamine accumulation and depletion in muscle and viscera of catfish to propose proper withdrawal periods. One group of catfish was fed a commercially available diet that contained 30, 100 and 300 mg melamine per kg diet for 14 days. To investigate residual melamine contents in muscle and viscera, other experimental groups were fed a melamine free diet after being fed melamine for 7 days. The residual amount of melamine was analyzed by LC-MS/MS. The melamine concentration in muscle was estimated to be 3.7 mg/kg after 6 days of feeding with a diet containing 300 mg melamine/kg. After 2 days of culture with a melamine free diet, the residual melamine was depleted and the concentration had decreased from 1.15 mg/kg to 0.19 mg/kg in the muscle of catfish fed a diet containing 300 mg melamine/kg for 7 days. The residual amount of melamine was reduced to 0.03 mg/kg in muscle after 7 days of culture with a melamine free diet and was undetectable after a prolonged culture period of 14 days. Catfish tend to excrete melamine rapidly after oral administration and changes in body color were not observed during the short dosing period.

• Journal of fish pathology
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• v.31 no.2
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• pp.115-122
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• 2018

The Houttuynia cordata has been utilized for various beneficial purposes in humans mainly because of its potent antioxidant principle quercitrin present in this plant. This study examines the possibility of producing a functional sea food commodity containing active principle quercitrin by feeding H. cordata for a extended period. Spotted sea bass (Lateolabrax maculatus) were fed a diet containing H. cordata at 0.1-1.0% levels for 1 month and tissue concentrations of quercitrin were analyzed in serum, hepatopancreas and muscle. It was observed that quercitrin was found in the ranking order of hepatopancreas>muscle>serum. After a bolus administration of quercitrin (20 mg/kg, oral) to spotted sea bass and Nile tilapia (Oreochromis niloticus), idential rank order was observed after 48 hr. In contrast, the order was liver>serum>muscle in rat and mice, indicating that higher quercitrin distribution occurs to the muscle in fishes compared with in mammals tested. High residue concentration of qeurcitrin in the edible tissue can be an advantageous property in terms of functional food production. High level H. cordata extract inclusion of 1.0% seems to have detrimental effects in spotted sea bass leading to growth retardation and hepatic damage. It was concluded that incorporation of H. cordata extract into diet can be a way of producing healthy foods. However the level of active extract needs fine tuning to avoid toxicity to fishes.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.209-216
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• 2008

This study was conducted to investigate the effects of selenium feeding and supplementation in diet on the concentration of selenium in blood and velvet antler of spotted deer(Sika deer). Three spotted deer were fed high selenium concentration(6mg/kg DM). Absorption and retention rates of selenium were examined by evaluating selenium concentrations in feces and urine. Stress-related hormones and serum biochemical parameters in blood were also evaluated for the purpose of detecting any negative effect by the high level of selenium feeding. Eight spotted deers were randomly assigned to two groups and were fed with one of two diets for 20 days, which were with or without the addition of 6mg selenium /kg diet. Concentration of selenium in velvet antler was evaluated. Selenium concentration in blood of spotted deer fed high level selenium for 30 days was significantly increased(p<0.05), retention rate of selenium reached 59.15%. No differences in level of stress-related hormone and biochemical parameters(NEFA, ALT, AST) in blood were observed by feeding high level selenium. The diet with selenium significantly increased concentrations of selenium in top(0.11 vs 0.45ppm; p<0.001), middle(0.08 vs 0.21ppm; p<0.01) and basepart(0.08 vs 0.15ppm; p<0.05) of velvet antler.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.337-343
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• 1998

In a feeding trial, Jamunapari male kids (18) of about 4 months age were equally divided into two groups of nine animals each. Goats in the experimental group were fed sun-dried pelleted Leucaena leucocephala leaves and those in the control group were offered a conventional diet without Leucaena leaves as per Kearl (1982) recommendations for a period of 6 months. Daily dry matter intake DMI/100 kg BW was $3.13{\pm}0.04kg$ in the Leucaena group and $3.30{\pm}0.05kg$ in the control. There were significant (p < 0.01) differences in the apparent digestibilities of DM, OM, CP, EE, CF and NFE being lower in the Leucaena group. Contents of digestible crude protein (DCP) and total digestible nutrients (TDN) were 11.40 and 52.20%, respectively, in the Leucaena group and 14.04 and 66.10%, respectively in the control. The nitrogen in the Leucaena group was not well utilized as compared to the control, though kids were in positive nitrogen balance in both the groups. The average daily weight gain of kids on pelleted Leucaena was $29.95{\pm}2.60g$ as against $42.09{\pm}3.24g$ observed in the control. The mean DMI/kg LW gain was significantly (p < 0.01) higher in the Leucaena group ($14.70{\pm}0.78kg$) as compared to the control ($11.55{\pm}0.46kg$). The Hb, BUN, SGOT and SGPT concentrations were statistically similar in both the groups. Histopathological examination of thyroid gland of goats sacrificed at the end of experiment did not reveal any signs of colloidal goitre associated with mimosine toxicity. No significant pathological alterations were observed in vital organs irrespective of dietary treatment. Sundried, pelleted Leucaena foliage appears to be a promising potential feed for growing goats without any significant deleterious effect.

• Toxicological Research
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• v.34 no.1
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• pp.41-48
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• 2018

The efficacy of highly active antiretroviral therapy (HAART) has led to an increase demand for therapeutic use, thereby necessitating investigation into drug toxicity. This study was designed to investigate the in vivo effects of HAART on sperm parameters and testicular oxidative stress in lean and obese rats. Wistar rats (males, n = 40, weighing 180~200 g) were assigned randomly into 4 groups and treated accordingly for 16 weeks as follows: Control (C): lean group fed with standard rat chow; Diet induced obesity (DIO): obese animals fed a high caloric diet; C + ART: lean animals treated with HAART; DIO + ART: obese animals treated with HAART. An antiretroviral drug combination of Tenofovir, Emtricitabine and Efavirenz at a dose of 17, 26 and 50 mg/kg/day was administered for the latter 6 weeks via jelly cube feeding. At the end of the experimental period, sperm analysis was performed on sperm collected from the caudal epididymis, while the testis was homogenized for antioxidant enzyme and lipid peroxidation assays. Results showed that HAART significantly decreased sperm motility (p < 0.05) in both lean and obese animals, and viability (p < 0.05) in the DIO group. Testicular glutathione, catalase and superoxide dismutase were significantly decreased (p < 0.05), while Thiobarbituric acid reactive substances (TBARS) levels were significantly increased (p < 0.05) when the DIO+ART group was compared to Control group. Thus, the decreased sperm qualities associated with HAART might be as a result of increased testicular oxidative stress prominent in obese animals.