Epidemiological Investigation And PCR Detection Of Cryptosporidium Species From The Intensive Chicken Farms In Luoyang

Cryptosporidiosis is caused by Cryptosporidium species which is a diarrhoeadisease in humans and domesticated animals. Cryptosporidium is able to infect morethan240hosts, and threat health of humans and animals. Cryptosporidiosis is one ofthe most common parasitosis in domestic fowls and birds. It has been reported morethan30birds are infected with Cryptosporidium species, and the clinical signs ofdigestive tract and respiratory symptom are commonly seen C. meleagridis, one ofaivian Cryptosporidium species, can infect humans and others mammals, and have thepublic health significance. In the present study, the epidemiology investigation ofCryptosporidium species from the intensive chicken farms in Luoyang, then theCryptosporidium isolates obtained were identified according to the morphology ofoocysts, transmission study, genotypic analysis of18S rRNA genes.A survey was carried out to determine the prevalence of Cryptosporidium speciesin chickens of the intensive poultry industry of Luoyang.359fecal samples from eightintensive chicken farms of Luoyang were collected and examined the presence ofCryptosporidium oocysts by the Sheather’s sugar flotation technique and the modifiedacid-staining method from May2011to April2012. The results showed that the totalinfection rate of Cryptosporidium species was15%(54/359) in the intensive poultryindustry of Luoyang, and the positive rate in the10-50-old-age chickens were higherthan that of other old ages. According to the morphological characteristics of oocysts,two distinct kinds of Cryptosporidium oocysts were isolated from chickens, andpreliminarily were identified as C. baileyi and C. meleagridis.To verification species of Cryptosporidium oocysts from the intensive chickenfarms in Luoyang,3-old-age chicken were inoculated into craw with Cryptosporidiumoocysts which collected in this survey. Results showed that the patent period was in4 days post infection, and the number of oocysts in feces increased obviously, itsexcreted the peak number of oocysts at8days post infection, and the duration ofoocysts excretion was8～15days. After dissected, scrapping of different tissues wereexamined for oocysts or other endogenous stages of Cryptosporidium species, oocystswere found only in the trachea and the bursa of Fabriciius. These results indicated thatCryptosporidium in chickens is C. baileyi.In our study,2isolates of Cryptosporidium were successfully amplified andsequenced by PCR method based on18S rRNA gene. Sequence data were analyzedwith online alignment, phylogenetic relationships analysis were performed usingDNAStar. Phylogenetic analysis revealed that the similarity of2isolates with C.baileyi was100%. These findings showed that cryptosporidiosis of chicken wasinfected commonly in Luoyang, and the risk evaluation of Public Health from chickensof the intensive poultry industry of Luoyang and the source of infection should be paidattention, and will be helpful for prevention of Cryptosporidiosis in humans andavian．...