• Parasites, Hosts and Diseases
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• v.51 no.2
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• pp.147-154
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• 2013

To control coccidiosis without using prophylactic medications, a DNA vaccine targeting the gametophyte antigen Gam56 from Eimeria maxima in chickens was constructed, and the immunogenicity and protective effects were evaluated. The ORF of Gam56 gene was cloned into an eukaryotic expression vector pcDNA3.1(zeo)+. Expression of Gam56 protein in COS-7 cells transfected with recombinant plasmid pcDNA-Gam56 was confirmed by indirect immunofluorescence assay. The DNA vaccine was injected intramuscularly to yellow feathered broilers of 1-week old at 3 dosages (25, 50, and $100{\mu}g/chick$). Injection was repeated once 1 week later. One week after the second injection, birds were challenged orally with $5{\times}10^4$ sporulated oocysts of E. maxima, then weighed and killed at day 8 post challenge. Blood samples were collected and examined for specific peripheral blood lymphocyte proliferation activity and serum antibody levels. Compared with control groups, the administration of pcDNA-Gam56 vaccine markedly increased the lymphocyte proliferation activity (P<0.05) at day 7 and 14 after the first immunization. The level of lymphocyte proliferation started to decrease on day 21 after the first immunization. A similar trend was seen in specific antibody levels. Among the 3 pcDNA-Gam56 immunized groups, the median dosage group displayed the highest lymphocyte proliferation and antibody levels (P<0.05). The median dosage group had the greatest relative body weight gain (89.7%), and the greatest oocyst shedding reduction (53.7%). These results indicate that median dosage of DNA vaccine had good immunogenicity and immune protection effects, and may be used in field applications for coccidiosis control.

• Parasites, Hosts and Diseases
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• v.49 no.3
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• pp.213-219
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• 2011

This experiment was conducted to assess the changing patterns and relative values of acute phase proteins and inflammatory cytokines in experimental caprine coccidiosis. Eighteen newborn kids were allocated to 3 equal groups. Two groups, A and B, were inoculated with a single dose of $1{\times}10^3$ and$1{\times}10^5$sporulated oocysts of Eimeria arloingi, respectively. The third group, C, received distilled water as the control. Blood samples were collected from the jugular vein of each kid in both groups before inoculation and at days 7, 14, 21, 28, 35, and 42 post-inoculation (PI), and the levels of haptoglobin (Hp), serum amyloid A (SAA), TNF-${\alpha}$, and IFN-${\gamma}$ were measured. For histopathological examinations, 2 kids were selected from each group, euthanized, and necropsied on day 42 PI. Mean Hp concentrations in groups A and B (0.34 and 0.68 g/L) at day 7 PI were 3.2 and 6.3 times higher than the levels before inoculation. The mean SAA concentrations in groups A and B (25.6 and 83.5 ${\mu}g$/ml) at day 7 PI were 4.2 and 13.7 times higher than the levels before inoculation. The magnitude and duration of the Hp and SAA responses correlated well with the inoculation doses and the severity of the clinical signs and diarrhea in kids. These results were consistent with the histopathological features, which showed advanced widespread lesions in group B. In both groups, significant correlations were observed for TNF-${\alpha}$ and IFN-${\gamma}$ with SAA and Hp, respectively. In conclusion, Hp and SAA can be useful non-specific diagnostic indicators in caprine coccidiosis.

• Korean Journal of Poultry Science
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• v.19 no.3
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• pp.151-160
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• 1992

Control of coccidiosis depends on medication, management, immunity, or some combination of these methods. Prophylactic medication with anticoccidials remains the primary method of control, although the development of drug resistance is a major problem. Shuttle and rotation programs are increasingly used to delay the onset of drug resistance. Sensitivity testing has become an important tool in the identification of what specific medications will be effective in specific poultry operations. Management techniques for the control of coccidiosis have not been totally effective because most disinfectants do not kill the coccidial oocysts. Present methods for vaccination are currently limited to the use of controlled doses of live coccidia. New vaccination methods under investigation include vaccination with attenuated strains or parasite antigens produced either by fractionating the parasites or genetically engineered sub unit vaccines.

• Korean Journal of Poultry Science
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• v.19 no.3
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• pp.161-176
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• 1992

Coccidiosis is caused by Eimeria infecting primarily the intestine of the susceptible host, thereby seriously impairing the growth and feed utilization of livestock and poultry. The genus Eimeria contains a number of obligate intracellular protozoan parasites with a complicated life-cycle involving both asexual and sexual stages of development. The desire to develop a vaccine against Eimeria has Promoted active research to elucidate the mechanisms of protective immunity and identification of candidate vaccine antigens. Protozoa are unique in their modes of transmission and nature of disease manifestations, the significance of which should be considered in the development of a control strategy. An intricate and complex interplay of different cell populations and cytokines is involved not only in the pathogenesis of coccidiosis but also in the development of protective immunity Thus, comprehensive understanding of the events leading to protection following Eimeria infection will be crucial for the development of an effective vaccine.

• Korean Journal of Veterinary Service
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• v.39 no.1
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• pp.21-28
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• 2016

Protozoan parasite, the genus Eimeria, causes an intestinal disease, coccidiosis, in young broilers. Coccidiosis induces significant economic loss in poultry production. This study was designed to identify the prevalence of Eimeria spp. in broilers in Gyeonggi province, Korea. Fecal samples from broilers at 94 farms were collected in two chicken slaughterhouses between March and June 2015. Eimeria infection was determined by microscopic examination and PCR using ITS-1 region. The prevalence of Eimeria was 58.5% (55 of 94). E. acervulina was identified in 96.4% of samples, E. tenella in 81.8%, E. maxima in 12.7%, E. praecox in 12.7%, E. brunetti in 5.5%, E. necatrix in 1.8%, and E. mitis in 1.8%. Body weight (BW) of broilers infected with both E. tenella and E. acervulina ($mean=1.53{\pm}0.19^Bkg$) was significantly lower than broilers with E. acervulina positive/E. tenalla negative ($mean=1.74{\pm}0.07^Akg$) or Eimeria negative ($mean=1.65{\pm}0.15^Akg$) (Duncan's multiple range test, P<0.01). High prevalence of Eimeria tenella and the impact on the broiler body weight shows the importance of this protozoa in broiler industry. Development of the periodic monitoring strategy and systemic management for the purpose of the prevention/eradication of Eimeria infection among broilers is required.

• Korean Journal of Veterinary Research
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• v.51 no.3
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• pp.249-252
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• 2011

Cell culture systems for the protozoan Eimeria are not yet available. The present study was conducted to develop an animal model system by inoculating animals with a live Eimeria vaccine. This study was conducted on 3-day-old chickens (n = 20) pretreated with cyclophosphamide. The chickens were divided into 2 groups: the control group (n = 10) and the inoculated group that received the live Eimeria vaccine (n = 10). During the study period, we compared the clinical signs, changes in body weight, and number of oocysts shed in the feces of the control and inoculated group. This study showed that oocyst shedding was significantly higher in the chickens inoculated with live Eimeria oocysts than in the control chickens. Moreover, body weight gain was lesser in the animals in the inoculated group than in the control animals. Fecal oocyst shedding was observed in the inoculated animals. On the basis of these findings, we suggest that live Eimeria vaccination with cyclophosphamide pretreatment may be used to obtain an effective animal model for studying protozoan infections. This animal study model may eliminate the need for a tedious continuous animal inoculation process every 6 months because the live coccidiosis vaccine contains live oocysts.

• Korean Journal of Veterinary Service
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• v.46 no.1
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• pp.81-85
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• 2023

This case report is about hemolymph nodes found in a dairy cow whose function is still not fully elucidated. A 4-month Holstein cow presented severe respiratory symptoms and hematochezia for a while with respiratory acidosis and metabolic alkalosis. Coccidiosis was diagnosed and treated immediately, but the cow died from respiratory acidosis and metabolic alkalosis. At necropsy, no abnormal appearance in thoracic and peritoneal organs was observed, but hemolymph nodes were observed being multifocally stuck on omasum serosa and the subcutaneous fascia of abdominal region, and the larger dark red lymph nodes were found along the omasum great curvature. Microscopically, lymphoid depletion and lymphadenitis in the lymph nodes were examined to point systemic infection, and in the hemolymph node, multifocally demarcated pale lesions with macrophage infiltration and fibrin deposition nearby subcapsular sinus. In subcapsular sinus of the hemolymph node, rod to linear gram-negative bacteria were found. Through this study, we might conclude that the hemolymph node is involved in pathogen phagocytosis.

• Proceedings of the Korean Society of Veterinary Service Conference
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• 1995.04a
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• pp.86.2-86
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• 1995

• Korean Journal of Veterinary Pathology
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• v.3 no.2
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• pp.69-71
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• 1999

A case of chronic cholangiohepatitis associated with Eimeria spp. is reported in a 6-month-old, male, native Korean goat. The goat died after having a 1-week history of diarrhea, anorexia and weight loss. At necropsy, numerous multifocal to coalescing, pale and mottled red foci were present throughout the liver. Histologically, numerous coccidian parasites in both sexual and asexual stages were found in the intrahepatic biliary epithelia and bile duct lumens. Based on the light microscopic and ultrastrastructural features, the parasites present in the liver were compatible with the genus Eimeria ; however, the species was not speciated.

• Korean Journal of Veterinary Research
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• v.18 no.1
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• pp.33-37
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• 1978

Enteritis occured in a herd of Korean native cattle in Gyeonbug district in February 1977. of 40 cattle ranging in age from 15 to 20 months, 17 had been sick for the past six days with main clinical findings of feces containing mucus and blood. Among affected cattle, feces of 8 cattle were examined bacteriologically and parasitologically to investigate the causative agent. The disease was diagnosed as bovine coccidiosis caused by Eimeria zurnii based on the detection of $o{\ddot{o}}cysts$ and one of cattle was infected E. bukidnonensis, too.