HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Related articles in JEQ Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Schijven, J. F. Articles by Yang, S. Search for Related Content PubMed PubMed Citation Articles by Schijven, J. F. Articles by Yang, S. Agricola Articles by Schijven, J. F. Articles by Yang, S. Related Collections Microorganisms Microbial and Colloid Transport Models Organic Compounds

TECHNICAL REPORTS

Waste Management

Release of Cryptosporidium and Giardia from Dairy Cattle Manure

Physical Factors

^a National Institute of Public Health and the Environment, Microbiological Laboratory for Health Protection, P.O. Box 1, 3720 BA Bilthoven, the Netherlands
^b George E. Brown, Jr. Salinity Laboratory, USDA-ARS, 450 West Big Springs Road, Riverside, CA 92507
^c Microbiology Program, 241 Boyce Hall, University of California, Riverside, CA 92521

^* Corresponding author (jack.schijven{at}rivm.nl).

Received for publication January 29, 2003. Various physical factors affecting the release rate of naturally occurring Cryptosporidium parvum oocysts and Giardia duodenalis cysts from dairy manure disks to sprinkled water were studied. The investigated factors included temperature (5 or 23°C), manure type (calf manure, a 50% calf and 50% cow manure mixture, and a 10% calf and 90% cow manure mixture), and water application method (mist or drip) and flow rate. Effluent concentrations of manure and (oo)cysts were always several orders of magnitude below their initial concentration in the manure, decreased gradually, and exhibited persistent concentration tailing. Release of manure and (oo)cysts were found to be related by a constant factor, the so-called release efficiency of (oo)cysts. A previously developed (oo)cyst release model that included these release efficiencies provided a satisfactory simulation of the observed release. An effect of temperature on the release of manure and (oo)cysts was not apparent. The manure and (oo)cyst release rates from cow manure decreased faster than those from calf manure, and (oo)cyst release efficiencies from cow manure were higher than those from calf manure. In comparison with mist application, dripping water resulted in higher release rates of manure and (oo)cysts and in higher (oo)cyst release efficiencies due to the increased mechanical forces associated with droplet impact. Mist application at a higher flow rate resulted in faster release, but did not affect the (oo)cyst release efficiencies. The data and modeling approach described herein provide insight and an enhanced ability to describe the influence of physical factors on (oo)cyst release.

Abbreviations: C_m, aqueous-phase manure concentration • C_p, aqueous-phase (oo)cyst number concentration • E, (oo)cyst release efficiency • E_Crypto, oocyst release efficiency • E_Giardia, cyst release efficiency • f_cow, fraction of cow manure • m_ip, initial (oo)cyst number concentration in the manure • Q, water flow rate

Related articles in JEQ:

This Issue in Journal of Environmental Quality

JEQ 2004 33: 1177-1182. [Full Text]  

This article has been cited by other articles:

				A. K. Guber, D. R. Shelton, Y. A. Pachepsky, A. M. Sadeghi, and L. J. Sikora Rainfall-Induced Release of Fecal Coliforms and Other Manure Constituents: Comparison and Modeling Appl. Envir. Microbiol., December 1, 2006; 72(12): 7531 - 7539. [Abstract] [Full Text] [PDF]