• Korean Journal of Veterinary Service
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• v.25 no.4
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• pp.357-370
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• 2002

This experiment was performed to investigate apoptosis during undergoing patho-genesis of Salmonella gallinarum(SG)-infected chicks. 16 days old, 49 chicks was infected with SG (10$\^$6/-10$\^$8/ CFU/㎖) experimentally, they were autopsied to remove liver, spleen, intestine and lung at 1, 6, 12hr, 1, 2, 4 and 7 day post infection(PI) respectively, for H-E and TUNEL staining. Grossly, white foci in the liver and enlarged spleen were seen on 4 day PI and coppery bronze liver, dark-red discolored intestine, green-yellowish discolored and enlarged spleen was observed on 7 day PI. Histopathologically, multi focal necrosis in the liver, follicle hyperplasia in the spleen and inflammatory cells infiltration in the intestine were shown from 2 day PI and more severely observed on 4 day and 7 day PI. In TUNEL analysis, apoptotic cells reached a maximum at 6hr PI in the liver and intestine and at 12hr PI in the spleen, and then decreased the levels of controls by 7 day PI.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.49-57
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• 1997

We developed a sensitive, nested reverse transcription-polymerase chain reaction (RT-PCR) to detect Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in animal tissues. Total RNA was extracted from blood, lung or kidney samples of experimentally-infected hamsters by using the guanidine isothiocyanate buffer-acid phenol-chloroform method. Genus-reactive outer primers were derived from the consensus region of the G1 gene sequences of several hantaviruses. Serotype-specific primers were selected within the region amplified by the outer primers. To examine the sensitivity and specificity of the test, we diluted known quantities of Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in human or hamster immune sera before performing the nested RT-PCR. We could detect as little as 1 pfu of virus, even in the presence of high-titer neutralizing antibodies, and the serotype-specific primers amplified only homologous serotype viruses. RT-PCR with these primers demonstrated virus in the blood of experimentally-infected hamsters as early as four days to as late as 30 days after infection. A comparison of a standard immunofluorescent antibody screening test (IFAT) to nested RT-PCR with RNA extracted from lung or kidney tissues of the hamsters, demonstrated that RT-PCR to be more sensitive for identifying viruses in these tissues.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.1013-1016
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• 1996

Since 1993, sudden and massive death has occurred among penaeid shrimp, Penaeus orientalis cultured in Korea. We investigated the pathological characterizations on the spontaneously and experimentally infected penaeid shrimp. The major gross findings of the spontaneous cases were 2-6mm sized-white spots on the inside of the carapace and reddish discolorization. Histopathologically, massive necrosis of lymphoid organ, degeneration and necrosis of epithelia of epidermis and foregut were observed in both spontaneous and experimental cases. Amphophilic to basophilic intranuclear inclusion bodies were readly observed epithelia of epidermis, foregut and gills. Electron microscopy revealed enveloped, non-occuluded ellipsoid to rod shaped virus particles, within the nucleus, in the lymphoid organs and interstitial cells of hepatopancreas of both spontaneously and experimentally infected shrimps. The size of the virion was $375{\times}167nm$, and the nucleocapsid was $290{\times}75nm$. The causative agent causing massive death in penaeid shrimps in Korea resembles baculovirus associated with white spot syndrome (WSBV) occurred in Taiwan in virus morphology and gross and histological changes of the shrimps.

• Parasites, Hosts and Diseases
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• v.48 no.2
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• pp.139-143
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• 2010

Reptiles were known to serve as paratenic hosts for Centrorhynchus (Acanthocephala: Centrorhynchidae) in Korea, but the infection course in experimental animals was not elucidated yet. In this study, the tiger keelback snakes (Rhabdophis tigrinus) were collected and digested with artificial pepsin solution, and the larvae of Centrorhynchus were recovered from them. Then, the collected larvae were orally infected to rats for developmental observations. In rats, all the larvae were observed outside the intestine on day 3 post-infection (PI), including the mesentery and abdominal muscles. As for the development in rats, the ovary of Centrorhynchus sp. was observed at day 15 PI, and the cement glands were 3 in number. Based on the morphological characteristics, including the arrangement of proboscis hooks, these larvae proved to be a species of Centrorhynchus, and more studies were needed for species identification.

• Biomedical Science Letters
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• v.11 no.1
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• pp.71-77
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• 2005

The etiologic agents of haemorragic fever with ranal syndrom (HFRS) in Korea are Hantaan and Seoul virus in the genus Hantavirus, family Bunyaviridae. In order to elucidate the role of maternal immunity to Hantavirus infection in rats, the protective effect of the maternal antibody were studies by using rats experimentally infected with Seoul virus strain HR80-39. Antibody titers of sera and viral antigen against Seoul virus were investigated by indirect immunofluorscence antibody technique (IFA). The dam sera had IFA antibody titers ranging from 1:128 to 1:1,024 after parturition. In fetuses, IFA antibody titers ranged from 1: 16 to 1:64 just after birth, increased to peak titers ranged from 1:256 to 1:1,024 in the 2nd week after birth. Challenged newborn rats had IFA antibody titers ranging from 1:64 to 1:1,024 after inoculation. No viral antigen was detected in lungs or other organs of the newborn rats. The maternal antibody to Seoul virus was transferred prenatally through placenta and postnatally via colostrum from immune dams to their offspring. These results demonstrated that maternal antibody to Seoul virus was quite effective in protecting newborn rats against same virus infection.

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.199-204
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• 2007

Metacercariae of Gynaecotyla squatarolae (Digenea: Microphallidae) were discovered from the shore crab, Macrophthalmus dilatatus, purchased at a market in a coastal town of Taean-Eup, Chungcheongnam-do, Republic of Korea. Their adult flukes were confirmed by experimental infection of rats. The metacercariae of G. squatarolae were elliptical ($391.1{\times}362.5{\mu}m$), and the excysted metacercariae had progenetic genital organs, including the ovary and testes. To obtain adult flukes, 6 Sprague-Dawley rats were fed 500 metacercariae each, and killed at days 2, 4, and 6 post-infection. The adult flukes were identified as G. squatarolae (Yamaguti, 1934) Yamaguti, 1939, based on morphological characters, including 2 ventral suckers (1 large and 1 small), a large genital atrium equipped with the cirrus and the metraterm, separated male and female genital pores, a transversely long cirrus pouch, and extensive vitelline follicles. In the present study, it has been first proven that the shore crab M. dilatatus is a second intermediate host for G. squatarolae in the Republic of Korea.

• Parasites, Hosts and Diseases
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• v.49 no.2
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• pp.133-138
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• 2011

This study was undertaken to investigate the hematological and biochemical changes in experimentally infected goats with Besnoitia caprae from the time of infection till 360 days post-infection (PI). Six male goats were inoculated subcutaneously with $13{\times}10^7$ bradyzoites of B. caprae, and blood samples were collected from the jugular vein. The total erythrocyte and total leukocyte counts, hematocrit value, and differential leukocyte counts were determined. Serum biochemical analysis, including the total protein, albumin, total globulin, cholesterol, triglyceride, chloride, testosterone, calcium ($Ca^{2+}$), inorganic phosphorus, sodium ($Na^+$), potassium ($K^+$), iron ($Fe^{2+}$), glucose, serum amyloid A (SAA), haptoglobin (Hp), fibrinogen, ceruloplasmin, aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase, and alkaline phosphatase, was undertaken. Skin biopsy from the limbs were collected at weekly intervals and histologically examined for Besnoitia cysts. Cysts were present in the skin biopsies of the leg of the infected goats from day 28 PI. There were variations in hematological analyses, but no significant difference was seen. From day 30 to 360 PI, results showed that SAA, Hp, fibrinogen, and ceruloplasmin concentrations increased, whereas testosterone concentrations decreased. Infected goats exhibited decrease of albumin and increase of serum total protein and globulin concentrations. By contrast, there were no significant differences in the remained analyses concentrations.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.1-8
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• 1998

Chickens at 3-weeks of age were inoculated with a highly virulent strain (SH/92) of Infectious Bursal Disease Virus(IBDV) through ocular and cloacal routes. The infected chickens were killed at 6, 12, 24, 48, 72, and 96 hrs post inoculation (PI) and Bursa of Fabricius(BF) were collected. The sizes of bursal follicules in infected chickens decreased at 48 to 96 hrs PI. Histologically the cellular changes were first evident at 12 hrs PI and characterized by condensation of nuclear chromatin of bursal lymphocytes indicating apoptosis. By 24 hrs PI apoptotic lymphocytes dramatically increased. In addition infiltration of heterophils were also seen in the follicles and in the interfollicular connective tissues. At 48 hrs PI, cystic cavities were observed in the follicles. As the infection advanced the bursal follicles showed atrophy accompanied by disappearance of heterophils and reduction in number of lymphocytes in the cystic cavities which was replaced by proteineous materials. The nuclei of most affected lymphocyte stained positively with the in situ end labeling for apoptosis. Electron microscopy showed viral particles with crystalline array in the lymphocytes of BF infected with IBOV. These results indicated that SH/92 IBDV infection in chickens caused increased apoptosis in the BF.

• Korean Journal of Veterinary Research
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• v.62 no.4
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• pp.30.1-30.6
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• 2022

In the study, zinc oxide nanoparticles (ZNOPs) at concentrations of 20, 40, and 60 mg/kg were tested for their antimicrobial action against the oocysts of Eimeria tenella. The oocysts of E. tenella were isolated from the feces of broilers received at the veterinary hospital in Diwaniyah Province and initially diagnosed by compound optical microscopy. The oocysts were confirmed molecularly by polymerase chain reaction targeting the ITS1 gene with a molecular weight of 409 bp. The results in the first week showed that ZNOP concentrations of 20 and 40 mg/kg possess various activities against E. tenella, while 60 mg/kg was the most effective in reducing excreted oocysts compared to the positive control and amprolium group, along with the appearance of mild symptoms and a mortality rate of 0.8%. In the second week of infection, excreted oocysts and mortality rates generally decreased in all treated groups. A comparison of all groups showed that the 60 mg/kg ZNOP-treated group had a significantly lower number of excreted oocysts, and all birds in this group recovered during the second week of infection. These findings revealed the prospect of using ZNOPs against E. tenella in challenging situations of the appearance of resistance to anticoccidial agents.

• Journal of Veterinary Clinics
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• v.29 no.2
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• pp.154-159
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• 2012

The efficacy of water soluble formulation of diclazuril (Coccimuel-S 0.5%) was tested against $Eimeria$ spp. infection broiler chickens. The experiment was performed both experimentally infection and in the field test. Coccimuel-S composed with diclazuril induced a marked inhibitory effect on the different stages of $Eimeria$ life cycle in experimentally infected broiler chickens treated with the drug. The tested dosage levels of Coccimuel-S (0.5 ml/L, equivalent to diclazuril 2.5 ppm) in drinking water showed the significant effect compared with the control group in controlling coccidial infection and reducing the total oocyst numbers, lesion and fecal scores ($p$ < 0.001). In addition, testing of Coccimuel-S (0.25 and 0.5 ml/L) in naturally infected poultry farms (1,200 broiler chickens), showed the significant anticoccidial effect compared to control ($p$ < 0.001). In conclusion, addition of Coccimuel-S at the dose of 0.25 and 0.5 ml/L in the drinking water, induced efficacious effect for the treatment of coccidiosis in naturally coccidia infected broiler chickens.