The present study was carried out to evaluate the efficacy of the experimentally prepared injection of nitroxynil-levamisole against liver fluke and gastrointestinal roundworms in goats and cattle. For the purpose, the dose confirmation trial, the dose reduction trial and clinical field trial were conducted according to "the guidelines for evaluating the efficacy of anthelmintics in ruminants" approved by the General Meeting of the 9th International Conference of the World Association for the Advancement of Veterin ary Parasitology" in 1981.

The results obtained are summarized as follows ;

1) A single dose of 10mg/kg of nitroxynil injection alone against the liver fluke and that of 5.0mg/kg of levamisole injection alone against gastrointestinal roundworms in goats were highly effective in the cure rate and the egg reduction rate, respectively.

2) A single dose of the experimentally prepared compound injection at the dose levels of nitroxynil 10.0mg-12.0mg/kg and levamisole 5.0mg-6.0mg/kg was highly effective in the egg reduction rates of both liver fluke(98.4%-100%) and gastrointestinal roundworms(97.3%-98.4%) without any side reaction in goats.

3) A single does of the experimentally prepared compound injection at the reduced dose level of nitroxynil 7.5mg/kg and levamisole 5.0mg/kg was highly effective in the egg reduction rates of both liver fluke and gastrointestinal roundworms in goats.

4) In the clinical field trial, a single dose of the experimentally prepared compound injection at the reduced dose level of nitroxynil 7.5mg/kg and levamisole 5.0mg/kg showed also very high efficacy in the cure rates and the egg reduction rates of both liver fluke and gastrointestinal roundworms in Korean cattle, dairy cow and beef cattle. However, it was not effective against Ostertagia sp. among gastrointestinal roundworms. No side reactions were noted.

The present study was carried out to obtain more information clarification of the susceptibility of the snails, Lymnaea pervia and L. auricularia to the common liver flukes, Fasciola hepatica and F. gigantica. The snails were collected from paddy field and irrigation route in a rural area located along the Han-gang riverside. Cercariae naturally shed from the snails were examined for identification for Fasciola spp. On the other hand, L. pervia and L. auricularia were artificially bred and the offsprings were divided into 3 groups according to day of age; baby snail group(5-7 days of age), young group(15-17) and adult group(more than 60), respectively, and used for infection of miracidia of F. hepatica and F. gigantica. The liver flukes were collected from Korea cattle and morphologically classified for the experiment. Eggs of F. hepatica and F. gigantica were cultured in the laboratory. After hatching, miracidia were used to infect the snails.

The results obtained in the present study were summarised as follows ;

1) Cercariae were naturally shed from both species of snails and cercariae of Fasciola spp. were found from 3(1.2%) among 250 individuals of L. pervia, but not from 200 individuals of L. auricularia.

2) Among 376 worms of Fasciola spp., 23(6.1%) were F. hepatica, 144(38.3%) were F. gigantica and 209(55.6%) were intermediate form, respectively.

3) Infection rates in the baby, young and adult snail group of L. pervia treated with F. hepatica miracidia were revealed as 57.6%, 53.1% and 47.9%, respectively, and with F. gigantica were 100.0%, 95.6% and 86.4%, respectively. The differences of infection rates between the corresponding groups of the former and the latter were highly significant(p<0.005). However. infection rates in the baby and young groups of F. hepatica- or F. gigantica-treated L. auricularia were very low, and no infection was established in the adult groups.

From the results. it is evidenced that L. pervia is the most suitable intermediate host for F. gigantica and F. hepatica in Korea.

The present study was carried out to examine the effect of a carcinogen, aflatoxin B₁ on the pathogenesis of the bile duct changes in mice experimentally infected with Clonorchis sinensis metacercariae. A total of 75 male albino mice of the BALB/c strain was used, and divided into 3 group; group I, treated with 1.0ppm aflatoxin B₁ in drinking water alone for 12 weeks; group II, given 50 Clonorchis sinensis metacercariae alone and group III, given 50 metacercariae at the beginning of the 12 week treatment with 1.0 ppm aflatoxin B₁ in drinking water. Three mice were served as untreated-uninfected normal control. All mice were fed the standard protein diet which was synthesized and supplied by the Laborarory of Sam-Lip Food Co. Since the 4th week three mice from each group were removed and sacrigiced at 4 week interval up to the 32nd week. The hepatobiliary tissues were extracted and subsequently prepared for light microscopic examination. The tissue specimens were stained with hematoxylin and eosin. Mice in group I showed no significant changes except the lower degrees of bile ductular proliferation and inflammatory cell infiltration at the portal regions at an earlier stage. In groups II and III there were remarkable together with extensive acute and chronic inflammatory cell infiltrations, cellular atypia and periductal fibrosis from earlier stages. However, in group III the histopathological changes observed were more prominent than those in group II throughout the observation. As the time elapsed, they showed gradual regression with some fluctuations in the degrees. No any evidences of malignant changes of epithelial cells were noted in group II, but in group III the first tumor was found at the 28th week and the second one was at the 32nd week, respectively. Histologically the tumors observed were well differentiated adenocarcinoma of the bile duct. It was appeared that the tumors were of peripheral origin with a tendency of multifocal growth. They also showed an infiltrative growth pattern, increased mucin droplets, increased nuclear-cytoplasmic ratio and nuclear hyperchromatism. No hepatocellular carcinoma was noticed throughout the observation. In conclusion, it was suggested that Clonorchis sinensis infection promotes carcinogenic action aflatoxin B₁, a carcinogenic agent.

Citations

Citations to this article as recorded by  

• Effect of Clonorchis sinensis infection and dimethylnitrosamine administration on the induction of cholangiocarcinoma in Syrian golden hamsters
  J H Lee, H J Rim, U B Bak
  The Korean Journal of Parasitology.1993; 31(1): 21.     CrossRef