• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.350-358
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• 2013

Both 13-week and 1-year studies in dog were required for pesticide registration in domestic pesticide control authority. It is raising issue up whether to request 1-year dog study of pesticides using non-food crop. So at this investigation, relevant toxicity test to establish acceptable daily intake (ADI), target organs, difference of no-observed adverse-effect levels (NOAELs) in 13-week and 1-year of 166 active ingredients are analyzed. The data were evaluated to determine if the 13-week dog study and the long term studies in two rodent species (mice and rats) without 1-year dog study were sufficient for the identification of NOAELs and lowest observed adverse effect levels (LOAELs) for the derivation of ADI. Toxicity end points and dose response data from 13 week and 1-year studies were compared. The analysis showed that 68 ADIs of the 166 pesticides were established from dog studies. Major target organs of dog studies were liver in 49 cases, body weight change in 21 cases, cholinesterase inhibition in 16 cases, and alteration in hematology in 14 cases. Similarity of target organ in 13-week and 1-year was 73%. 22 of 40 pesticides had similar critical effects regardless of duration and had NOAELs within a difference of 1.5-fold of each other. For the remaining 18 pesticides, 14 items had lower NOAELs in the 1-year study than 13-week study primarily due to dose selection and spacing. In only 10% of the cases were additional toxic effects identified in the 1-year study that were not observed in the 13-week study.

• Progress in Medical Physics
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• v.11 no.1
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• pp.59-71
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• 2000

It is possible to obtain a fast CT scan during breath holding with spiral technique. But the risk of radiation is increased due to detailed and repeated scans. However, the limitation of X-ray doses is not fully specified on CT, yet. Therefore, the purpose of the present study is to define the limitation of X-ray doses on CT The CT unit was somatom plus 4. Alderson Rando phantom, Solenoid water phantom, TLD, and reader were used. For determining adequate position and size of organs, the measurement of distance(${\pm}$2mm) from the midline of vertebral body was performed in 40 women(20~40 years). On the brain scan for 8:8(8mm slice thickness, 8mm/sec movement velocity of the table) and 10:10(10mm slice thickness, 10mm/sec movement velocity of the table) methods, the absorption doses of exposed area of the 10:10 were slightly higher than those of 8:8. The doses of unexposed uterus were negligible on the brain scan for both 8:8 and 10:10. On the chest scan for 8:8, 8:10(8mm slice thickness, 10mm/sec movement velocity of the table), 10:10, 10:12(10mm slice thickness, 12mm/sec movement velocity of the table) and 10:15(10mm slice thickness, 15mm/sec movement velocity of the table) methods, 8:8 method of the absorption doses of exposure area was the most highest and 10:15 method was the most lowest. The absorption doses of 8:10 method was relatively lower than those of the other methods. In conclusion, the 8:10 method is the most suitable to give a low radiation burden to patient without distorting image quality.

• Journal of fish pathology
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• v.1 no.1
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• pp.5-30
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• 1988

This is a comprehensive study for considering the effective treatment and control program of bacterial disease occurring in common carp, israel carp, color carp, crucian carp, eel and tilapia by clarifying the causes, mechanism of infection and onset and the diagnostic criteria. As a first step, the authors investigated the external views, gross and histopathologic findings of diseased fish using 450 infected fishes obtained from various farmer of Korea. This infection was characterized by hyperemia, hemorrhage and swelling of body surface and fins, congestion of liver, spleen, kidney, inflammation of intestine, hemorrhagic inflammation of various tissues, and necrosis and ulcer of various tissues were accompanied in serious cases. Bacteriologically, Aeromonas hydrophila and Edwardsiella tarda were isoiated from these fishes. Particularly in the regular check on 222 eels, 177 strains were isolated as 29.94% of Aeromonas hydrophila, 48.58% of Edwardsiella tarda and 21.47% of Flexibacter columnaris. Hexibacter columnaris was isolated from corroded gill of eels. The identical disease was occurred by innoculating the isolated Aeromonas hydrophila and Edwardsiella tarda and the identical strains were isolated from infected experimental fishes. The eels which were diagnosed Aeromonas disease from Kwangju, Pusan accompanied hemorrhage, swelling of body surface and fins, inflammation of stomach and intestine containing mucous fluids mixed with the pathogens. Color carp and crucian carp which were innoculated with the isolated 5 strins of Aeromomas hydrorphil died within 3 or 4 days accompanying with the characteristics of Aeromonas disease. Edward disease was characterized by abscesses of body surface, pus formation with concentration on phagocytes. The size of absecsses increased with progression elf disease. There were also various abscesses at internal organ and white nodules appeared in kidney. Histologically, various progressive granuloma were examined without inflammation of intestine. Columnaris disease of eels showed no hemorrhage except slight white body color. In autopsy, most of internal organs appeared normal and there were no septic odors. The only character was corrosion of gills. In order to treat these bacterial diseases, infected fishes must bathe in 20ppm chloramphenicol or kanamycin solution for 1 hour. Besides, medication program in oral ingestion of 75mg/kg chloramphenicol per day continuing for 5 to 7 days. After injecting the formalin treated Aermonas hydrophila antigen into carp, relatively high agglutination titer showed between 3 weeks and 6 weeks. Though this titer decreased from that time, it was continued for 18 weeks. In the case of injecting the formalin treated Edwardsiella tarda antigen into tilapia, the titer also increased. But tilapia which were immersed in the suspension fluid of the formalin treated Edwardsiella tarda showed no increase of the titer.

• Korean Journal of Poultry Science
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• v.33 no.4
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• pp.283-293
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• 2006

Two experiments were conducted to investigate the effects of dietary activated charcoal mixed with wood vinegar (AC) on broiler performance and antibiotics residue in eggs. In experiment 1, a total of low hundred fifty, 1-day-old male broile. chicks (Ross) were divided into 6 groups, consisting 3 replicates of 25 birds each, and 134 one of the six experimental diets: devoid of AC and antibiotics (negative control), devoid of AC with 0.1% antibiotics (positive control), devoid of antibiotics with 1% AC, with 0.1% antibiotics and 1% AC, devoid of antibiotics with 2% AC, with 0.1% antibiotics and 2% AC, for 5 wks. Feed consumption and body weights were measured weekly. At the end of the experiment, eight birds from each group were selected and sacrificed. The relative weight of organs and characteristics of breast muscle were investigated. There were no significant differences in feed intake, body weight gain and feed conversion rate among the treatments. There were also no significant differences in the relative weight of breast meat, leg and liver. The abdominal fat tended to be decreased by the dietary AC. Significant differences were shown (P<0.05) in meat redness (a) and yellowness (b) among the treatments. However, the sensual characteristics of breast muscle was not affected by the dietary treatments. There were significant differences in total microbes, Coli forms and lactic acid bacteria (P<0.05) among the treatments. In experiment 2, a total of ninety, 40-wk-old Hy-line Brown laying hens were divided into 3 groups, consisting 3 replicates of 10 birds each and fed medicated control diet devoid of AC or diets containing 1% AC and 2% AC for 2 wks. The residue of antibiotics in Plasma and egg Yolk were significantly decreased (P<0.05) in 2% AC group compared to that of control. This study suggest that dietary AC may improve the external quality of edible meat and reduced antibiotics residue in chicken eggs without affecting laying performance.

• Applied Microscopy
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• v.40 no.3
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• pp.125-132
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• 2010

Captured specimens of the lesser white-toothed shrew, Crocidura suaveolens were classified into three age classes by tooth wear and seasonal variations of reproductive organs were investigated. Molars of juveniles had not tooth wear and the height of the third molars were lower than the first and second molars, young adults had smooth tooth wear and the third molars reached to the first and second molars, and old adults had heavy tooth wear and the third molars also reached to the first and second molars. On the basis of histological examination, seasonal variation of breeding was confirmed that breeding season of adult males was from early February to early October, having a peak of the breeding in April and July, and non-breeding season was from in the middle of October to late January. Young and old adult males of the breeding season had large testes with enlarged seminiferous tubules filling with numerous germ cells and expanded caudal epididymides with a vast number of spermatozoa, Young and old adult males of the non-breeding season had the small testes with the extremely slender seminiferous tubules filling with only spermatogonia and the reduced caudal epididymides without spermatozoa. Males weighing more than 3.9 g in the body weight and 0.013 g in the testis and epididymis weight reached sexual maturation in breeding season, and the females weighing more than 3.8 g in body weight of the breeding season were pregnant condition having 5~6 litters or had the Graafian follicles and the corpus lutea in the ovary.

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.277-290
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• 1987

This paper dealt with etiological studies on the acute fatal disease of Angora rabbits occurring as a group in Korea. The disease was confirmed as an acute infectious disease caused by virus. The results obtained were summarized as follows: The disease produced a high morbidity in the rearing Angora rabbits and a high mortality in the infected rabbits, and was acute. The infected rabbits died soon without premonitory signs after inappetence. The body temperature of the affected rabbits rose to $40^{\circ}C$ and nearly all deaths occurred within 48 hours after inoculation. In many cases a bloody foam was visible from the nostrils after death. According to the progress of the disease the nervous signs, such as ataxia, paralysis of the legs, and torticollis could be recognized in the some cases. Rabbits that had recovered from the disease were severe emaciation, and bristly and sparse hairs. In macroscopical findings, there were hemorrhage and edema of the lung, hemorrhage or hyperemia of the tracheal and broncheal mucosae, appearance of blood-tinged effusion in the respiratory tract. The principal lesions were found in the liver. Usually the lobular necrosis of the liver cells was progressed, and focal necrosis and hemorrhagic spots of various sizes were often observed in the liver. Liver was as a whole pale. In chronic cases, however, there was a slight liver cirrhosis with the atrophy of the parenchymal cells. The other lesions encountered grossly consisted of swelling and petechiae of the kidney, hyperemia and hemorrhage of the spleen, catarrh of the small intestine, and hyperemia of the brain. The urinary bladder contained a lot of turbid urine or bloody urine and urinary cast, and was distended with the urine. In microscopical findings, the most striking lesions occurred in the liver and may be classified as viral hepatitis. The hepatic lesions were initially characterized by progression from periportal to peripheral necrosis of the lobules with the infiltration of mononuclear cells. Focal necrosis of various sizes, hemorrhage and hyperemia were often observed in the hepatic lobules. In chronic cases, there were intensive infiltration of lymphocytes, proliferation of fibroblasts, appearance of plasmal cells, and atrophy of parenchymal cells in the hepatic tissue. Perivascular lymphocytic infiltration and meningitis were seen in the brain and spinal cord. In the kidney, there were acute glomerulonephritis, hemorrhage, necrosis of the uriniferous tubules, and retention of eosinophilic substance within the renal tubules. Proliferation of fibroblasts and infiltration of mono-nuclear cells were found in the interstitial stroma of the kidney in chronic case. There were also hemorrhage and edema in the lung, hyperemia and hemorrhage in the trachea and bronchus, perivascular lymphocytic infiltration and focal myocardial necrosis in the heart, hyperemia and hemorrhage in the spleen, vacuolization and desquamation of mucous epithelia in the urinary bladder, catarrhal inflammation of the small intestine, hemorrhage in the adrenal cortex and hyperemia in the other organs. In the electron microscopical findings of the hepatic tissue, crystals of viral particles appeared in the cytoplasm of the hepatocytes and the sinusoidal endothelial cells, and the viral particles, were small in size and polygonal. The authors suppose the virus may belong to picornaviridae family of RNA viruses. Also immature virus-like particles, dilated rough endoplasmic reticulum and destruction of nuclear membrane were seen in the hepatocytes. From these results, it is concluded that the sudden death is an acute viral disease characterized by hepatitis and the affected rabbits may be died of viremia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.683-689
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• 2006

This study was established to investigate the effect of germanium-fortified yeasts on the serum lipid composition and immune system of human body. All 50 subjects with the age range of $50{\sim}75$ were entered in this clinical trial for 6 months. The effects were determined by the proliferative responses of immune-mediated cells, T-cell, B-cell and NK-cell during daily supplementation with/without germanium-fortified yeast. The results of hematology and blood chemistry didn't show any significant differences during administration periods. Serum lipid compositions also didn't show any significant differences during administration periods except triglyceride (TG) and VLDL-cholesterol. TG and VLDL-cholesterol levels were increased significantly by the consumption of germanium-fortified yeast (p<0.05). Immune mediated T-celt and NK-cell didn't increased in both control and test group supplemented with germanium fortified yeast, while B-cell increased in the germanium fortified yeast group after 8 week (p<0.05). Also $TNF-{\alpha}$ increased in the group of germanium fortified yeast after 8 week (p<0.05) but not in the control group. From the above results, germanium fortified yeast is expected to be useful on the improvement of the cellular immune response and protection of organs from various chronic diseases.

• Korean Journal of Poultry Science
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• v.43 no.3
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• pp.149-157
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• 2016

This study was performed to investigate the effects of the stocking density (standard stocking density (SSD, $495cm^2/bird$)) vs. high stocking density (HSD,245cm2/bird) and challenge with lipopolysaccharide (LPS, 5mg/kg BW) on the stress-related physiological indicators in chicks. There was a significant (p<0.05) decrease in body weight, but not in the weight of immune organs, between the SSD and HSD groups. The LPS group resulted in a significant (p<0.05) increase in the weights of the thymus and bursa of fabricius compared with the SSD group. Plasma biochemical components, including aspartate transaminase (AST), alanine transaminase (ALT), blood urea nitrogen, Ca, P, creatine kinase and uric acid, markedly (p<0.05) increased in the LPS birds, although no difference in these parameters was observed between the SSD and HSD birds. Furthermore, the birds challenged with LPS showed a significant (p<0.05) increase in the plasma corticosterone level, although this hormone did not differ between the SSD and HSD groups. In the mRNA expression of pro-inflammatory cytokines, hepatic $IL-1{\beta}$, IL-6 and iNOS in the LPS group significantly (p<0.05) increased compared with those in the SSD group. Thymic mRNA expression of $IL-1{\beta}$, IL-6 and IL-18 in the LPS group also significantly (p<0.05) increased compared with those in the other groups. In addition, mRNA expression of $IL-1{\beta}$ in the bursa of fabricius of the LPS group increased (p<0.05) without affecting the other cytokines. Under high stocking density, thymic $IL-1{\beta}$ was the only cytokine that was up-regulated compared with the SSD group. In conclusion, an acute stress induced by LPS challenge profoundly affected immune organ weight, blood biochemical profiles and pro-inflammatory cytokine expression, while chronic stress did not markedly affect biochemical and immunological parameters, suggesting that chicks under high stocking density could be adapted to prolonged stressors.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.168-177
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• 2009

This study was conducted to investigate the dietary effects of locally grown herbs (Mentha piperascens, PM; Rubus coreanus, RC; Tagetes patula, MG) on the growth performance and meat quality of broiler chicken. A total of 600 1-d-old Ross male broiler chicks were divided into eight groups and were fed control diets (antibiotics-medicated or non-medicated commercial diets) or experimental diets (non-medicated diets containing 0.3 or 0.5% PM, 0.3 or 0.5% RC, or 0.3 or 0.5% MG) for 5wk. The body weight gains and feed conversion rates (FCRs) in all the groups that were fed diets containing PM, RC, or MG were significantly improved compared to those in the non-medicated control group (p<0.05). The relative weights of various organs, the serum cholesterol levels, and the GOT/GPT activities in all the groups were also not significantly different. The superoxide dismutase (SOD)-like activities in the groups that were fed diets containing 0.3% PM or 0.3% MG were significantly increased compared to those in the non-medicated control group (p<0.05). The number of cecal lactic-acid bacteria in the groups that were fed diets containing 0.3% PM or 0.5% RC tended to increase. The malondialdehyde contents in the leg muscles were significantly lowered by feeding with PM or MG (p<0.05). The physicochemical properties of the edible meat, including the shear force, water-holding capacity, heat loss, pH, and muscle color degrees $(CIEL^*.\;a^*.\;b^*)$, were not affected by the dietary treatments. It has been suggested that spontaneous Korean plants promote the growth of broilers and may delay lipid oxidation in edible muscles without any negative effect when added in broiler diets.

• Korean Journal of Poultry Science
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• v.47 no.3
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• pp.169-180
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• 2020

This study examined the effects of a probiotic complex (PC) containing Lactobacillus plantarum, Bacillus subtilis, and Saccharomyces cerevisiae on growth performance, organ weight, immune parameters, fecal microbial count, and noxious odor in broiler chicks. A total of 216 birds (4-day-old) were fed a basal diet (CON) and a diet supplemented with 0.25% (PC1) and 0.5% (PC2) of PC until 35 days of age. No difference in body weight, feed intake, and FCR was observed among the groups. The intestinal mucosal weight of the PC1 group was greater than that of the CON group without affecting weights of the other organs. Intestinal secretory immunoglobulin A (sIgA) levels in the PC2 group increased significantly (P<0.05) compared with that in the CON group. The PC2 group also had a strong tendency for elevated blood sIgA levels. Dietary PC did not affect the level of interleukin-1β in the blood and mucosal tissues or alter maltase, sucrase, and leucine aminopeptidase activities in the intestinal mucosa. The PC2 group had higher colony-forming units (cfu) for L. plantarum and S. cerevisiae, but lower cfu for E. coli than those in the CON group. Compared to the CON diet, the PC2 diet resulted in a decreased H₂S concentration and a tendency toward decreased CH₃SH concentration. In conclusion, a 0.5% PC diet showed increased sIgA and desirable microbial population, and decreased noxious odor in the feces, suggesting that PC could be applied as an environmentally friendly feed additive in broiler chicks.