• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.225-228
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• 2007

We observed the time gap between oocyst shedding and antibody responses in mice (3-week-old C57BL/6J females) infected with Cryptosporidium parvum. Oocyst shedding was verified by modified acid-fast staining. The individually collected mouse sera were assessed for C. parvum IgM and IgG antibodies by enzyme-linked immunosorbent assay from 5 to 25 weeks after infection. The results showed that C. parvum oocysts were shed from day 5 to 51 post-infection (PI). The IgM antibody titers to C. parvum peaked at week 5 PI, whereas the IgG antibody titers achieved maximum levels at week 25 PI. The results revealed that IgM responses to C. parvum infection occurred during the early stage of infection and overlapped with the oocyst shedding period, whereas IgG responses occurred during the late stage and was not correlated with oocyst shedding. Hence, IgM antibody detection may prove helpful for the diagnosis of acute cryptosporidiosis, and IgG antibody detection may prove effective for the detection of past infection and endemicity.

• 대한수의학회지
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• 제51권3호
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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.

• Parasites, Hosts and Diseases
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• 제34권4호
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• pp.255-258
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• 1996

닭에 있어서 닭와포자충의 재감염에 대한 방어기전을 이해하기 위하여 장기간에 걸쳐 혈청IgG항체가를 경시적으로 조사하였다. 2일령의 SPF 병아리(Dekalb-Warren, Sex-Sal-Link)에 $5{\;}{\times}{\;}10^5$개 그리고 IgG가가 정상으로 복귀한 다음 10일인 340일령에 $1{\;}{\times}{\;}10^7$개의 닭와포자충의 오오시스트를 경구투여하고 나서 채혈하여 간점형광항체법을 이용하여 혈청IgG 항체가를 측정하였다. IgG 가는 감염후 3일부터 38일까지는 대조군과 차이가 없었으나 45일부터 1:21.33으로 상승하기 시작하여 120일에 1:512로 최고치에 이른다음 점점 떨어져 330일에 1:4로 정상치에 이르렀다. 도전 감염후 7, 14, 28일에 각각 1:16, 1:512, 1:1.024로서 점점 높아져 정점에 이른다음 급격히 떨어져 63일에 정상으로 복귀하였다. 한편, 대조군의 항체가는 모두 1:2~1:4의 범위에 있었으며 이 원충의 도전감염전 및 후에 있어서 분변으로부터 집충시켜 제작한 Kinyoun 항산염색표본에서도 오오시스트를 전혀 검출할 수 없었다. 분변내의 오오시스트의 소실 시기와 최초 감염에 있어서 IgG가의 피이크는 일치하지 않았다.

• 한국동물위생학회지
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• 제35권1호
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• pp.25-31
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• 2012

This study examined the efficacy of natural ingredient formulated herbal medicine as feed additives against coccidiosis in broiler chicken. Medicinal herbs used in this study were Artemisia annua, Pulsatilla chinensis, Clematis chinensis and Scutellaria baicalensis. Two week old chicks were administered with 1% ingredient formulated herbal medicine. Observations of the efficacy were confirmed by examining the lesion score, histopathological appearance of cecum, shedding of fecal oocyst and production index in farm. S. baicalensis of the most effective substance were analyzed by UPLC. The results are as follows; among various types of Chinese medicine, the most efficacious ingredient was found to be pure bicalein. The major index substance is bicalein and $13{\mu}g/ml$ per gram was found. Feeding of chickens with S. baicalensis induced the coccidiostat effect and reduced the fecal shedding of E. tenella oocyst by 14%. Experimental results on a farm, feed conversion ratio and weight gain and production rate in the group with natural ingredient formulated additives than in control group increased. The rate of weight gain (%) in each experimental group showed 108% and 126% increase while the mortality rate was 1.4% lower than the control group. The investigation showed that the most efficacious ingredient was found to be S. baicalensis among herbal medicine products for coccidiostats. However, as it was found in the farm experiment that pure S. baicalensis alone is economically unviable. The additives with cocktailed of efficacious ingredient are suggested to be implemented for effective protection against coccidiosis.

• Parasites, Hosts and Diseases
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• 제59권4호
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• pp.403-408
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• 2021

Avian coccidiosis has a major economic impact on the poultry industry, it is caused by 7 species of Eimeria, and has been primarily controlled using chemotherapeutic agents. Due to the emergence of drug-resistant strains, alternative control strategies are needed. We assessed anticoccidial effects of berberine-based diets in broiler chickens following oral infection with 5 Eimeria species (E. acervulina, E. maxima, E. tenella, E. mitis, and E. praecox). When 0.2% berberine, a concentration that does not affect weight gain, was added to the diet, the 4 groups infected with E. acervulina, E. tenella, E. mitis, or E. praecox showed significant reductions in fecal oocyst shedding (P<0.05) compared to their respective infected and untreated controls. In chickens treated 0.5% berberine instead of 0.2% and infected with E. maxima, fecal oocyst production was significantly reduced, but body weight deceased, indicating that berberine treatment was not useful for E. maxima infection. Taken together, these results illustrate the applicability of berberine for prophylactic use to control most Eimeria infections except E. maxima. Further studies on the mechanisms underlying the differences in anticoccidial susceptibility to berberine, particularly E. maxima, are remained.

• Parasites, Hosts and Diseases
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• 제33권4호
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• pp.377-382
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• 1995

Cryptosporidium muris(strain MCR)를 3주령의 각 마우스에 $2{\;}\times{\;}10^6$개의 오오시스트차 그 10 배 단계 희석계열을 $2{\;}{\times}{\;}10^5$까지 5단계를 만들어 경구접종하여 오오시스트 배설g/100g을 조사하고 나서 초감염내과 마우스에 처음에 50 mg/100g. 그 24시간 후에 12.5 mg/100 g의 carrageenan을 복강내 투여하고 그 6시간 후에 다시 $2{\;}\times{\;}10^6$개의 오오시스트를 2차접종하여 면역원성을 조사하였다 일반적으로 오오시스트 투여량이 많을수록 오오시스트 배설량이 많았으나 prepatent period(9-11일간)와 오오시스트 생산이 피이크에 이르는 기간(16-36일간)은 짧았다. Patent period는 61-64일간이었으며 15-31일간에 걸쳐 오오시스트가 많이 생산되었다. 한편 IgG 항체가의 현저한 상승과 분변내 오오시스트 소멸은 일치하였다 Carrageenan 투여군은 오오시스트 재차접종 후 16 0-18.0(16.6)일부터 61-66.5(64.8)일까지 46.0-51.5(49.0)일간 대조군은 15.5-17.5(16.4)일부터 29.0-31.0(29.8)일까지 12.0-16.0(14.2)일간에 걸쳐 소수의 오오시스트가 검출되었다. 재차접종 직전의 말초혈액내 대식세포수 및 복강내 대식세포 활성은 대조군에 비하여 carrageenan 투여군이 현저하게 낮았다(P < 0.05). 이는 Me blocker인 carrageenan을 투여하였음에도 불구하고 이 원충의 2차감염이 미약하였다는 것은 이 원충의 면역원성이 매우 강력하다는 것을 뜻한다.

• Parasites, Hosts and Diseases
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• 제35권4호
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• pp.245-250
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• 1997

마우스에 있어서 쥐와포자충 감염에 대한 면역기전을 해명하기 위하여 이 원충을 최초 및 도전 감염시켜 위점막 비만세포수의 동태를 관찰하였다. ICR계 SPF3주령 마우스에. 그리고 감염 내과 후 분변 내의 오오시스트 음전 후에 두 번에 걸쳐 각각 $2{\;}{\times}{\;}10^6$의 쥐와포자충 (MCR주) 오오시스트를 경구투여하였다 최초 감염 후 5일 및 도전 감염 후 10일 간격으로 희생시켜 위를 적출하여 pH 2.0으로 조정된 Camoy's solution에 5-6시간 고정한 다음 pH 0.3으로 조정된 l% alcian blue에서 2시간. pH 1.0의 0.5% sihnin에서 5분간 염색하여 위점막 비만세포수를 계수하였다. 위점막 비만세포수는 최초 감염 후 15일에서 25일까지 최고치에 이른 다음 30일에 감소하여 그 이후에는 정상으로 복귀하였으며. 도전 감염 후 20-30일에도 역시 증가하였다 최초 감염 후 이 세포의 증가 후에는 분변에 배설되는 오오시스트의 수도 감소하였으며. 도전 감염 후에는 분변에서 오오시스트를 거의 검출할 수 없었다 이러한 사실로 미루어 보아 이 세포는 최초 감염 흡충체 배출. 그리고 도전 감염의 방어기전과 관련이 있다고 생각한다.

• 대한수의학회지
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• 제51권2호
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• pp.101-105
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• 2011

We investigate the resistance of Cryptosporidium (C.) parvum oocysts to commercial bleach treatment. The viability and infectivity of C. parvum oocysts suspended in 100, 50, 25, 12.5, 6.3 or 3.2% aqueous commercial bleach for 10, 30, 60, 120 or 180 min at room temperature were assessed by nucleic acid Syto-9 staining, histologic examination of ileum and infectivity to immunosuppressed neonatal C57BL/6N mice. Although the viability was decreased compared with normal oocysts, all oocysts in contact with serially diluted commercial bleach for 180 min were alive by nucleic acid dye Syto-9 staining. And, microscopic examination of ileum sections revealed developmental stages of C. parvum in all mice. The oocyst shedding patterns between mice infected with oocysts contacted with commercial bleach and normal control mice were not significantly different each other. Although commercial bleach is widely used as a bacterial and viral disinfectant, the present findings indicate that it is not an effective disinfectant for C. parvum oocysts under practical conditions. Authors conclude that, therefore, it is undesirable to recommend commercial bleach as a disinfectant for C. parvum oocysts.

• Journal of Veterinary Science
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• 제23권6호
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• pp.91.1-91.9
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• 2022

Three parameters, body weight gain (BWG), intestinal lesion score (LS) and fecal oocyst shedding, were compared in broilers infected with major parasitic species; Eimeria acervulina, E. maxima, and E. tenella. First, two- and three-week-old chickens with Eimeria infection showed LS of approximately 3, but two-week-old chickens were more correlated with BWG. Second, significant differences in BWG were observed between male and female broilers challenged with Eimeria. Finally, E. maxima-infected broilers among three Eimeria species showed a higher relationship between BWG and LS, suggesting three considerations such as genders, age and Eimeria species for Eimeria experiments.

• 한국임상수의학회지
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• 제23권3호
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• pp.243-250
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• 2006

The chickens fed with the feeds supplemented with green tea(GT) and lactic acid bacteria(LB) were infected orally with 10,000 oocysts per chicken of E. maxima. The groups administered with the feeds supplemented with GT by 0.5% and 2.0% of feed showed the significant levels of decreasing in the number of oocysts shed for 5 days after E. maxima infection. The feeds supplemented with LB by 0.1% and 0.5% of feed were less effective in reducing the number of the fecal oocyst, compared with the groups administered with GT. To evaluate the immunoregulatory effects of the feed additives, the expression patterns of IL-2 and IFN-r in spleen cells were studied by RT-PCR and ELISA. The higher levels of IL-2 transcripts after E. maxima infection were observed in the groups with n, compared with the groups with LB and the mixture of GT and LB. The $IFN-\gamma$ mRNA bands were observed in the all of experimental groups except the uninfected control. The culture supernatants of Con A-stimulated spleen cells($5{\times}10^6cells/ml$) were measured for the concentration of IL-2 and $IFN-\gamma$ by ELISA. The levels of IL-2 and $IFN-\gamma$ on days 3 and 7 after E. maxima infection were significantly augmented in the groups with n. These results indicated that GT-supplemented feeds resulted in higher reduction of oocyst-shedding and more enhanced immune responses in the chicken infected with E. maxima, as compared with LB-supplemented feeds. According to the results, it was implicative that the supplements could be utilized for development of feed additives for anti-coccidiosis.