Progress 07/15/06 to 07/14/09
Outputs
OUTPUTS: The outputs described below followed work carried out in support of objective 1 (to determine the species/genotype of Cryptosporidium from the red river and from cattle in the Red River Valley) and objective 2 (to determine the genetic relatedness of C. parvum isolates from river and cattle samples). Presentations at national and international conferences: Data from this project have been presented at three National Water Quality conferences (Savannah, Georgia, 2007; Sparks, Nevada, 2008; St. Louis, Missouri, 2009). Data were presented on sources of Cryptosporidium in surface water, emphasizing the specific roles of cattle and wildlife. Data disseminated at the National Water Quality Conferences reached water industry professionals, regulators, and researchers in water quality and safety. Data were disseminated at an international workshop on opportunistic protists. These data reached researchers specializing in protist research. Data were disseminated at the II International Cryptosporidium and Giardia Conference, Mexico. These data, which focused on the age related distribution of Cryptosporidium in cattle from the region, reached researchers specializing in the study of Cryptosporidium and Giardia. Scientific article: A manuscript published in Veterinary Parasitology presented work on the age related distribution of Cryptosporidium in cattle. This manuscript has been cited 9 times during the period following its publication in 2008 and the completion of this report in October 2009. Consultations: Work from this project was disseminated to the Buffalo River Watershed District in Minnesota. Specifically, data from this project helped to identify a ranch that was contaminating the Buffalo River with cattle runoff. PARTICIPANTS: This project funded the PI, two MS students and two undergraduate students. TARGET AUDIENCES: Scientific community, farmers, biologists, ecologists, regulatory agencies, pollution control agencies PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our data show that while cattle and wildlife contributed to water contamination, the species of Cryptosporidium present were host adapted and not generally associated with human disease. We found the same C. andersoni genotype in cattle at a cattle ranch and in river water samples as far as 28 miles downstream of the ranch, thus clearly linking cattle to surface water contamination. These data, which include both species and genotype information, enhance our previous understanding of cattle as a source of Cryptosporidium in water. C. andersoni predominantly infects older cattle and has only rarely been found in humans. Although C. andersoni is not a significant human pathogen, cattle in this study may be a source of other pathogens such as Escherichia coli O157:H7. Cryptosporidium andersoni was the only species identified in water downstream of the cattle ranch while this species was only rarely found upstream of the cattle ranch. Conversely, wildlife genotypes predominated upstream of the cattle ranch but were not identified in downstream samples. This detected difference in Cryptosporidium ecology over a relatively short stretch of the river may be explained by a relatively high level of C. andersoni contamination in downstream samples. It is unlikely that wildlife genotypes are absent from downstream samples but rather that C. andersoni is present at high levels, which are selectively amplified during PCR. C. andersoni was the only species found in cattle, although the number of positive samples was low. No zoonotic C. parvum was found in cattle. The HSP70 subtyping method developed in this study may be useful to more specifically identify sources of contamination. C. andersoni from Site A2 (cattle ranch) and all water samples downstream of this site shared the same HSP70 subgenotype (subtype I). These data suggest that the cattle at Site A2 are the source of Cryptosporidium contamination in the water downstream. Wildlife was identified as a significant source of water contamination upstream of the cattle ranch. Previous studies have independently identified wildlife genotypes in water and characterized genotypes in wildlife, but this study is one of the first to study wildlife and water in the same area. We found the muskrat genotype I and vole genotype to be present in small mammals and adjacent river water samples. We found both Muskrat genotype I and the vole genotype in meadow voles, the most abundant small mammals detected. Meadow voles are prolific breeders and may produce up to 17 litters in a year (litter size of 4-8). Although the genotypes found in meadow voles are not known to infect humans, their relatively large abundance in population, indicates the importance of this wildlife species as source of water contamination. C. parvum and cervine genotype were identified in river water samples and these species have been associated with human disease. C. parvum commonly infects calves, but also infects other ruminants and humans. The cervine genotype, like C. parvum has also been reported to infect ruminants (deer and sheep) as well as rodents
Publications
- Pennil, C.C., Giddings, C.W. and McEvoy, J.M. 2007. Cryptosporidium parvum subgenotypes from humans and calves in Minnesota. The 2nd International Conference of Giardia and Cryptosporidium. Morelia, Mexico.
- Feltus, D.C., Giddings, C.W. and McEvoy, J.M. 2007. High prevalence of Cryptosporidium bovis and deer-like genotype in 6-8 month old beef cattle. The 2nd International Conference of Giardia and Cryptosporidium. Morelia, Mexico
- McEvoy, J.M. 2007. Sources of Cryptosporidium in a rural North Dakotan River. National Water Quality Conference, Savannah, GA.
- McEvoy, J.M. Pennil, C.C., Clark, M.E., Herges, G. Schneck, B.L. and Giddings, C.W. 2009.Cryptosporidium transmission in the Midwest United States. National Water Quality Conference, St Louis, MO.
- Pennil, C.C. 2009. Studies of Cryptosporidium: Tracking sources of contamination in water and identifying isolates using fluorescence in situ hybridization. MS Thesis
- Feltus, D.C., Giddings, C.W., Khaitsa, M.L. and McEvoy, J.M. 2008. High prevalence of Cryptosporidium bovis and the deer-like genotype in calves compared to mature cows in beef cow-calf operations. Veterinary Parasitology 151 (2-4) 191-195
- Pennil, C.C, Clark, M.E., Giddings, C.W. and McEvoy, J.M. 2008. Sources of Cryptosporidium in a rural watershed. International Workshop on Opportunistic Protists. Boston, MA.
- Pennil, C.C, Clark,M.E., Giddings, C.W. and McEvoy, J.M. 2008. Sources of Cryptosporidium in a rural watershed. National Water Quality Conference, Sparks, NV.
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Progress 07/15/07 to 07/14/08
Outputs
OUTPUTS: 1. Information on the source of Cryptosporidium in the Buffalo River has been shared with the Buffalo River Watershed District. Specifically, we were able to identify a feedlot that was contributing to water contamination. 2. We have shared our findings with the Fargo Water Treatment Plant, which is currently in the middle of an EPA source water testing program for Cryptosporidium. 3. We have presented our findings to engineering students at NDSU. The goal is to increase awareness of water contamination issues among civil engineers and encourage them to explore environmental engineering solutions to microbiological problems PARTICIPANTS: This project has involved collaboration with Dr Mark Clark, a population ecologist, who helped to study Cryptosporidium in mammals. We also worked with the Buffalo River Watershed District in Minnesota and Fargo Water Treatment Plant in North Dakota. This project has funded a graduate student and undergraduate students and has provided the graduate student the opportunity to attend an international conference on Cryptosporidium. TARGET AUDIENCES: Data from this project regarding Cryptosporidium sources and transmission in rural surface water is targeted at: 1] Regulatory agencies. Regulators do not currently require Cryptosporidium species information when assessing the quality of raw surface water for processing into drinking water. Yet, this and other studies have shown that species data are important for assessing the public health impact of Cryptosporidium in water. 2] Agricultural community. Approaches used in this study can be used to study the impact of livestock on water contamination in other regions 3] Scientific community. Data from this study will contribute to our understanding of Cryptosporidium transmission in rural areas. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Change in knowledge: We have linked Cryptosporidium contamination of surface water directly back to the contaminating feedlot, using knowledge of host adaptation and a genotyping tool that was developed as part of this project. Cryptosporidium andersoni is a cattle adapted species that is particularly associated with older cattle. While it is not considered a significant human pathogen, it has been associated with some cases of human cryptosporidiosis. Finding C. andersoni in water is a clear indication that cattle are the source. We sampled the Buffalo River immediately upstream and downstream of a cattle ranch. Contamination upstream was primarily caused by wildlife including voles, mice, and deer. All water isolates downstream of the cattle ranch were C. andersoni. Furthermore, we developed a method to genotype C. andersoni using a polymorphic region of the HSP70 gene and, using this method, we determined that isolates downstream were the same as those from cattle on the ranch.
Publications
- Feltus, D.C., Giddings, C.W., Khaitsa, M.L. and McEvoy, J.M. 2008. High prevalence of Cryptosporidium bovis and the deer-like genotype in calves compared to mature cows in beef cow-calf operations. Veterinary Parasitology 151 (2-4) 191-195 Pennil, C.C, Clark, M.E., Giddings, C.W. and McEvoy, J.M. 2008. Sources of Cryptosporidium in a rural watershed. International Workshops on Opportunistic Protists. Boston, MA, May 2008. Pennil, C.C, Clark, M.E., Giddings, C.W. and McEvoy, J.M. 2008. Sources of Cryptosporidium in a rural watershed. National Water Quality Conference, Sparks, Nevada, February 2008.
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Progress 07/15/06 to 07/14/07
Outputs
The goal of this project is to determine the role of cattle in Cryptosporidium contamination of rural water in North Dakota. To date, we have determined that beef cattle older than 6 months are not a significant source of C. parvum, the species responsible for most human cryptosporidiosis in the area. Instead they are infected with cattle adapted species and genotypes that are not associated with human disease. Pre-weaned beef calves at 6-8 months old are primarily infected with C. bovis and the deer-like genotype, while dams older than 2 years are primarily infected with C. andersoni. Neonate calves with diarrhea are a significant source of C. parvum and the subgenotypes of these calf isolates are similar to those from humans in the area. Surface water samples from the Red River watershed; including samples from the Red, Sheyenne and Pelican rivers, have tested positive for Cryptosporidium. Some genotypes present in surface waters are likely to have originated from
wildlife; however, C. andersoni was also found, which indicates that older cattle are the source. Interestingly, the sequence of the 18S rRNA gene from water isolates of C. andersoni had the same polymorphism as isolates previously recovered from dams in North Dakota.
Impacts
The model of cattle as the primary source of C. parvum infecting humans is likely to be over simplistic. Our data show an age related distribution of Cryptosporidium in beef cattle with C. parvum infecting neonates, C. bovis and the deer-like genotype infecting 6-8 month old calves and C. andersoni infecting cattle older than 2 years. This supports previous findings in dairy cattle in the Eastern United States. Using this age related model, we have shown that C. parvum isolates from calves are similar to those from clinically infected humans in the area. We have also shown that older cattle are a source of Cryptosporidium in surface waters; however, these older animals are not likely to be a significant source of human pathogenic species. Our findings have a major impact on how cattle are viewed as a source of Cryptosporidium in rural watersheds. Cryptosporidium risk reduction strategies should be based on a complete understanding of the species present in surface
waters, and when applied at the farm level, they should be temporally and geographically focused around calving. This approach would minimize undue economic burden on ranchers and water treatment facilities, while maximizing the reduction in disease associated with this important waterborne pathogen.
Publications
- Feltus, D.C., Giddings, C.W., Khaitsa, M.L. and McEvoy, J.M. High prevalence of Cryptosporidium bovis and the deer-like genotype in calves compared to mature cows in beef cow-calf operations. Submitted to Veterinary Parasitology June, 2007
- Pennil, C.C., Giddings, C.W. and McEvoy, J.M. (2007). Cryptosporidium parvum subgenotypes from humans and calves in Minnesota. Proceedings of the II International Giardia and Cryptosporidium Conference, Morelia, Mexico, May 2007
- Feltus, D.C., Giddings, C.W. and McEvoy, J.M. (2007). High prevalence of Cryptosporidium bovis and deer-like genotype in 6-8 month old beef cattle. Proceedings of the II International Giardia and Cryptosporidium Conference, Morelia, Mexico, May 2007
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