Investigation And Control Of Balantidium Coli Infection From The Intensive Pig Farms In Luoyang

Balantidium coli is the biggest protozoa in intestinal tract of humans and nonhuman primates. At present, research on B.coil mainly focuses on the epidemiological investigation, clinical diagnosis and treatment. However, little effort was spend on the research about its pathogenic mechanism. In the present study, survey of balantidiosis in pigs from the region of Luoyang was examined. Chinese medicines variety against B.coliwere screened in vitro culture system, and efficacy of these herbals was checked in pigs.1.1373feces samples (including370suckling piglets,375weaning piglets,348growing pigs and280breeding sows) were collected from10pig farms of Luoyang and examined with the direct smear method to determine status of pigs balantidiosis in Luoyang. Trophozoites of B. coli were detected on all the10farms, the positive rate was100%for the farm, The infection rates for different stages were30.8%for suckling piglets、54.7%for weaning piglets、52.0%for growing pigs、51.1%for sows, the average infection rate was31.5%～64.8%.2. In this study,18S rRNA, ITS1-5.8S rRNA-ITS2molecular marker technology were used to analyse the population characteristics of different isolates of B.coli from various pigs farms in Luoyang. The results of18S rRNA sequence analysis showed that all seven isolates from pigs belonged to a single species, B. coli in Luoyang, the similarity of seven isolates with Philippine isolates was more than99%. The results of ITS1-5.8S rRNA-ITS2sequence analysis indicated that B. coli exist two genotype, genotype A and genotype B, in the pig herds of Luoyang. SX isolates were genotype A of B. coli, and the remaining6isolates were genotype B.3. Currently national agriculture department bans to use nitroimidazole compounds into feed additives for the problem of drug residues, so we tested the effect of twenty two traditional Chinese medicines including Changshan, gallnut, Flos Lonicerae and ebony on B. coli using the in vitro toxicity test. According to the results of LC50, nine herbals were initially identified as effective drugs against B. coli, and the order of antibalantidium efficacy was dichroa febrifuga, galla chinensis, dark plum, lonicera Japonica, baikal skullcap root, common anemarrhena, betelnutpalm seed, medicine terminalia fruit and sweet wormwood herb.4. In order to determine the clinical efficacy of traditional Chinese medicine against B. coli, four drugs including metronidazole, oxytetracycline, dichroa febrifuga and galla chinensis were orally administrated to pigs in a large scale pig farm of Luoyang. The results showed that metronidazole group had the best effect. However, all of Chinese herbs played a role in the clinical effect on B.coli disease. According to the infection intensity of B. coli in feces of pigs, The recovering rates from balantidiosis were70%and50%in1weeks after the treatment with dichroa febrifuga and galla chinensis. These findings suggest that the traditional Chinese medicine can clinically treats.B.coli infection of pigs.