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Objective: Determination the effects of the bacterial entropathogens to increase infection of calves and cows to cryptosporidium.
Design: Descriptive study.
Animals: A total of 152 calves and 300 cows.
Procedure: Microscopic detection of cryptosporidium in the direct smears of feces samples from 3 farm in around Tehran, using smears, fixing with methanol, staining with
modified zeal-nielson, detecting oocysts under a light microscope with objective magnification of 40 X (at least in 20 microscope field), confirming the observation using magnification of 100 X. on the other hand, feces samples were cultured for detection of bacterial agents such as: Salmonella, E. coli, Proteus, Klebsiella, Campylobacter and Pseudomonas as well as microscopic observation for presence of acid-fast bacteria in the direct smears of feces.
Statistical analysis: Descriptive statistics.
Results: In this study, Cryptosporidium was detected in 40.7 8% of diarrheic calves of which 10.52% of cases had cryptosporidium alone, and in 30.26% of cases cryptosporidium was accompanied with at least one other pathogenic bacteria. In 3.28% of cases acid-fast organism was isolated alone. Target pathogens of this study was isolated at least in 34.3 3% of feces samples of cows. In
28% of cases Cryptosporidium was confirmed and in 5% acid-fast organism was observed.
Conclusion: The results of the present study showed that the infection rates are significantly higher in calves than in cows which may be the due to the age susceptibility to Cryptosporidium. It is suggested that hygiene of calf den is of great importance. J.Fac. Vet.Med. Univ. Tehran.
60,2:131-135,2005.