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Title: Survival kinetics of Cryptosporidium in swine facility wastes in Southern Piedmont and Coastal Plain watersheds

item BOWMAN, D
item LIOTTA, J
item Jenkins, Michael

Submitted to: USDA-CSREES National Water Quality Conference
Publication Type: Abstract Only
Publication Acceptance Date: 12/28/2007
Publication Date: 2/3/2008
Citation: Bowman, D.D., Liotta, J.L., Jenkins, M. 2008. Survival kinetics of Cryptosporidium in swine facility wastes in Southern Piedmont and Coastal Plain watersheds [abstract]. USDA-CSREES National Water Quality Conference, February 3-7, 2008, Sparks, NV.

Interpretive Summary:

Technical Abstract: Background The long-term objective of the study is to minimize the impact of swine rearing facilities on the watersheds within which these facilities are located by abrogating or reducing the number of oocysts of Cryptosporidium species leaving the facilities in their waste streams. It is believed that the oocysts of Cryptosporidium can be used to monitor how well the lagoons remove or destroy this and other pathogens to protect the environment from infectious agents. Methods The study is being conducted in three phases: (1) Determine the viability of oocysts within swine lagoons and material leaving the lagoons for land application. (2) Determine the effects of lagoon storage on the inactivation kinetics of oocysts placed within the lagoons in sentinel chambers. (3) Determine the inactivation kinetics of oocysts that have been land applied to forage crops after their treatment within a swine lagoon. To meet the first specific objective in the first year of the project we have begun to sample (once per month) 10 swine lagoons in the Southern Piedmont (7) and Coastal Plain (3); 4 lagoons are associated with finishing facilities, 4 with farrowing facilities, 1 with a nursery, and 1 secondary lagoon. Cryptosporidium oocysts were extracted using immunomagnetic beads, enumerated, assayed for viability with a dye permeability protocol, and genetically typed by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) protocol and DNA sequence analysis. In the samples from June and July for which analysis is complete, all but 3 of 19 (one missing) contained oocysts (from 34 to 431 oocysts/ml), while effluent from only 6 lagoons (37.5%) contained viable oocysts. PCR-RFLP has determined that the oocyst were not C. parvum. BLAST analysis on sequenced products is in agreement, but specific determination for all sequences has not yet been completed. Results and Conclusions In the summer months, a significant number of oocysts present in the lagoons are not viable. Further characterization for winter months will determine the potential variation in oocyst number and viability by season. Impact Statement Initial work indicates that a large portion of recovered oocysts are nonviable. Completion of the analyses performed on the remaining samples form the first year will indicate the effects of season on viability. This work will then produce baseline data for comparison with kinetic data to be generated in Year 2 with the sentinel chambers being used to place oocysts within the lagoons for varying periods. It is expected that major oocyst die-off will occur.