• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.745-747
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• 2015

Cryptosporidium, a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.

• Parasites, Hosts and Diseases
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• v.35 no.3
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• pp.181-188
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• 1997

In order to clarify the effect of cryptosporidiosis on immune response, histopathological changes associated with experimentally occurring bursal cryptosporidiosis in chickens were chronologically observed as the first step. A total of 150 2-day-old chickens was each inoculated orally with a single dose of 5 × 105 Cryptospori,mum bailevi oocysts. The chickens showed a normal profile of oocyst shedding in droppings. The bursa indices throughout the experimental period indicated negligible reactions. Numerous cryptosporidia occurred in the microvillous border of bursal epithelium between days 4 and 16 postinoculation (PI). Appearance of the most mast cells was followed by a dramatic loss of the protozoa in the bursa of Fabricius (BF). The distribution of the coccidium coincided with heterophil infiltration in the epithelium and adjacent lamina propria. The histopathological lesion was marked diffuse chronic superficial purulent bursitis with heterophil infiltration in the epithelium and adjacent lamina proprla and mucosal epithelial hyperplasia. These results suggest that the bursitis may induce immunosuppressive effect.

• Parasites, Hosts and Diseases
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• v.52 no.3
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• pp.251-256
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• 2014

A novel recombinant Bacille Calmette-Guerin (rBCG) vaccine co-expressed Eimeria tenella rhomboid and cytokine chicken IL-2 (chIL-2) was constructed, and its efficacy against E. tenella challenge was observed. The rhomboid gene of E. tenella and chIL-2 gene were subcloned into integrative expression vector pMV361, producing vaccines rBCG pMV361-rho and pMV361-rho-IL2. Animal experiment via intranasal and subcutaneous route in chickens was carried out to evaluate the immune efficacy of the vaccines. The results indicated that these rBCG vaccines could obviously alleviate cacal lesions and oocyst output. Intranasal immunization with pMV361-rho and pMV361-rho-IL2 elicited better protective immunity against E. tenella than subcutaneous immunization. Splenocytes from chickens immunized with either rBCG pMV361-rho and pMV361-rho-IL2 had increased $CD4^+$ and $CD8^+$ cell production. Our data indicate recombinant BCG is able to impart partial protection against E. tenella challenge and co-expression of cytokine with antigen was an effective strategy to improve vaccine immunity.

• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.32-42
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• 2013

Objectives: Cryptosporidium, a protozoan parasite, has been recognized as a frequent cause of waterborne disease due to its extremely strong resistance against chlorine disinfection. Although there has as yet been no report of a Cryptosporidium outbreak through drinking water in Korea, it is important to estimate the health risk of Cryptosporidium in water supply systems because of the various infection cases in human and domestic animals and frequent detection reports on their oocysts in water environments. Methods: This study evaluated the annual infection risk of Cryptosporidium in tap water using the quantitative microbial risk assessment technique. Exposure assessment was performed upon the results of a national survey on Cryptosporidium on the water sources of 97 large-scale water purification plants in Korea, water treatment efficacy, and daily unboiled tap water consumption. The estimates of the US Environmental Protection Agency on the mean likelihood of infection from ingesting one oocyst were applied for effect assessment. Results: Using probabilistic methods, mean annual infection risk of Cryptosporidiosis by the intake of tap water was estimated to fall within the range of $2.3{\times}10^{-4}$ to $1.0{\times}10^{-3}$ (median $5.7{\times}10^{-4}$). The risk in using river sources was predicted to be four times higher than with lake sources. With 0.5-log higher removal efficacy, the risk was estimated to be $1.8{\times}10^{-4}$, and could then be lowered by one-third. Conclusions: These estimations can be compared with acceptable risk and then used to determine the adequacy and priority of various drinking water quality strategies such as the establishment of new treatment technology.

• Journal of Veterinary Clinics
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• v.12 no.1
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• pp.911-916
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• 1995

Ionophorous antibiotics have been used popularly for the protection of avian coccidiosis, though Halo-fuginone which is derived from an extract of the Dichroa febrifuga, was developed as an antimalarial and anticoccidial agent. The antibiotics are regarded as the causes of residues in the avian products, therefore the author has tried to find out more safe herbal materials for the control of avian coccidiosis. Thus, the extracts of 5 kinds of herbs, roots of Pulsatilla koreana Nakai and Sophora flavescens Aiton, nuts of Quisqualis indica Linne, whole herbs of Artemisia annua Linne and Polygonum aviculare Linne, were investigated on the efficacy against E tenella. Survival rates, bloody diarrhea, lesion scores, body-weight gains and feed conversion rate were investigated at the 1st and the 2nd week after infection. The bloody diarrhea in the groups treated with P koreana, A annua, Q indica and P aviculare were milder than those in the groups treated with S flavescens and infected control. The lesion score in the groups treat.4 with herb extracts(2.00$\pm$0.82~2.65$\pm$0.89) were lower than those in the control group (2.80$\pm$0.7l). But, there was not significant in all infected groups. The body weight gai in the groups treated with P koreana, S flavescens, A annua and Q indica(291.74$\pm$15.76~303.43$\pm$51.90) were higher than that in the control group (283.71$\pm$16.53) but there was not significant. In a conclusion, analyzing the data of the survival rates, bloody diarrheal symptoms, lesion scores, body weight gains and oocyst excretions, the extract of S flavescens, P koreana, A annua and Q indica were effective. The further research on the above herbal materials will have been carried out by the author and the other researchers by means of the chemical analysis of the components.

• Korean Journal of Veterinary Service
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• v.28 no.4
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• pp.367-373
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• 2005

Coccidiosis of domestic fowl is a parasitic disease that infects poultry drastically and can cost the pastured poultry producer much in the course of a year. Two hundred forty, day-old-broiler chicks were purchased and were randomly divided in eight groups, containing thirty birds in each group. Decoquinate $6\%$, maduramicin ammonium $2\%$, monensin sodium $13.2\%$, salinomycin sodium $12\%$, a live attenuated vaccine, and trivalent live attenuated vaccine, was provided to the day chicks of six groups, respectively. The chicks of last two groups served as infected non-medicated and uninfected non-medicated, respectively. Feed consumption, weight gain, feed conversion ratio, mortality and oocyst count per gram feces were recorded during the conduction of the experiment. Among treated groups, performance of salinomycin group was significantly better (p<0.05) in all aspects. Salinomycin acts against the sporozoites, trophozoites and first generation schizonts and is highly effective against the economically important species of Eimeria. The present study confirms that use of salinomycin, as an anticoccidial, is a drug of choice.

• Parasites, Hosts and Diseases
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• v.36 no.1
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• pp.33-36
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• 1998

Hemagglutinin (HA) titers to SRBC were chronologically observed in chickens orally inoculated at 2 days of age with 5 × 105 oocysts of Cwptosporidium bniLeWi. All the infected chickens exhibited negligible HA titers by 44 days postinoculation (Pl) . The titers were elevated as time progressed. and peaked on day 52 Pl, declined gradually thereafter, and eventually reached to normal titers on day 92 Pl. On the contrary, the titers in uninfected chickens were higher in comparison with infected chickens during the experiment. Chickens infected with the protozoa showed normal oocyst shedding profiles during this period. These data suggest that C. bnilewi infection suppress development of humoral immunity to SRBC in chickens. It is possible that impairment of the bursa of Fabricius by cryptosporidiosis rendered chickens vulnerable to other pathogens.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.188-194
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• 1987

The development of antibody titers and crossreaction between Sarcocystis and Toxoplasma were investigated by means of IF A test and ELISA in pigs experimentally infected with $1.5{\times}10^6$ S. suicanis sporocysts and 10,000 T. gondii oocysts, respectively. The intact and soluble Sarcocystis antigens were prepared from the bradyzoites harvested by peptic digestion of infected pork. The intact and soluble Toxoplasma antigens were prepared from the tachyzoites in mouse peritoneal cavity. IgG antibodies in pigs infected with Sarcocystis and Toxoplasma, respectively were detected first at 2 weeks post infection on both IF A test and ELISA. The antibody titer to Toxoplasma reached its maximum at 6 weeks post infection and decreased thereafter. The antibody titer to Sarcocystis reached its maximum terminally. The cross-reaction titer in pigs infected with Toxoplasma against Sarcocystis antigen was up to 1 : 16 in IFA test and up to 1 : 32 in ELISA. The titer in control group was below 1 : 4 in both reactions.

• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.371-374
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• 1993

Fecal samples of cats purchased in Seoul were examined for helminth ova or protozoan oocysts from December 1987 to March 1988. Out of the 41 samples,31 (75.6%) were positive and 60 (146.3%) were cumulative positive for parasites. The followings were identified In the samples: Eggs of Toxocarn cacti. Clonorchis sinensis, Metoeonimn sp., Phnrvngostomum cordntum, Spirometra erinocei, Tcenia toenicejormis and oocysts of Isosporn sp. From nine autopsied cats, larvae of Anisakis simplex, adults of C. sinensis, M. yokogawai. P cordatum, S. erinacei and T. tqeniaejormis were identified. This is the first report on the detection of Anisakis larvae from cats In Korea. The possible role of cats as a source of human infection with each parasite was discussed. Key words: Cat, intestinal parasite, Anisckis simplex, Toxoccra cati, Clonorchis sinensis, Metagonimus yokogawai. Spirometro erinccei, Taenic tonniaelormis, Isospora Sp .

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.155-164
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• 1995

The location of actin and myosin of the several stages of Cwptosporinium parvum was observed. The tissue antigen of C. pcruum was prepared through immunosuppression of IgG mice with Depomedrol . The thin sectioned specimens, which were incubated with the IgG fraction of the rabbit polyclonal antibodies raised against chicken back muscle actin and bovine uterus myosin, were treated with 10 nm gold-conjugated goat anti-rabbit IgG, Electrodense particles were located mainly on the pellicles of all observed developmental stages of the parasites. The number of actin gold particles in the cytoplasm increased when the parasite was dividing actively as in case of meronts. Especially in macrogametocytes, a lot of actin and myosin particles were synthesized and storaged as amilopectin-like bodies. There were many actin gold particles along the microspikes of cytoplasmic membranes in various developmental stages. The actin and myosin observed in this study may play important roles to control the shape of the parasites and movement of cytoplasmic membranes as cvtoskeletal proteins.