Katoch, RajeshYadav, Anish2017-08-212017-08-212010No. of references 283http://krishikosh.egranth.ac.in/handle/1/5810029327The epidemiology of bovine cryptosporidiosis and its zoonotic potential in children and HIV positive patients of Jammu have been assessed. The prevalence studies were based on identification of Cryptosporidium oocysts in faecal samples by conventional (modified Ziehl- Neelsen), immunological (ELISA) and molecular (PCR) methods. Examination of 684 (432- cattle and 252- buffalo) and 2880 (cattle n=1440, buffalo=1440) faecal samples of bovine calves of organized and unorganized farms respectively, revealed an overall prevalence of Cryptosporidium spp. in 26.52 % animals. It was higher in organized farms (48.39 %) as compared to unorganized farms (21.31 %). Higher prevalence was observed in cattle calves (55.55%; organized farms, 26.18 %; unorganized farms) than the buffalo calves (36.11%; organized farms, 16.45 %; unorganized farms). Calves of 0-1 months age group (59.64 %; organized and 29.89%; unorganized farms) showed highest prevalence. Winter recorded the highest infection rate (71.92 %) in organized farm animals, whereas, in unorganized farms it was during monsoon season (33.19%). In both type of farms, summer recorded the lowest rate. Higher prevalence of Cryptosporidium spp. oocysts in diarrhoeic faeces having mucus (76.07%; organized farm and 32.57% unorganized farm), than those showing presence of blood was recorded. The relationship between intensity of infection and various epidemiological factors showed that higher intensity was there in calves of 0-1 month age group, having diarrhoea, with mucus, in winter season of organized farms and monsoon season in unorganized farms. Out of 120 diarrhoeic faecal samples of children examined, 17 (14.17%) were found positive for Cryptosporidium. Highest prevalence (19.15%) was observed in 6-12 months group and lowest (6.45%) in < 6 months of age. As per residing status a very high but non significant difference was observed in infection rate of Cryptosporidium in rural (16.95%)) and semi urban (14.29%) from urban children (5.26%)). Higher infection was observed in children having persistent (20.83%) type of diarrhoea as compared to acute (11.76%o) and chronic (4.76%) cases. Seasonal prevalence revealed significantly (P < 0.05) higher infection during monsoon than other seasons. Examination of 52 HIV infected individuals revealed, 15 (28.84%) positive for Cryptosporidium spp. Higher prevalence was observed in diarrhoeic patients (39.28%)) having chronic type of diarrhoea (40.0%). Prevalence was high (63.64%) in individuals having CD4 count <200 cells /μ1. Genetic characterization using PCR- RFLP revealed higher prevalence of C. parvum in children (76.47%) and C. hominis in HIV infected individuals (60%). Biological characterization confirmed the results of genetic characterization. The study highlights prevalence of cryptosporidiosis and associated risk factors to vulnerable groups i.e. bovine calves, children and HIV infected individuals. Molecular and biological characterization of Cryptosporidium spp. also established zoonotic role of C. parvum in Jammu district. Keywords: Cryptosporidium, Epidemiology, Bovine, Children, HIV patients, ZoonoticennullThesis