UNDERSTANDING RISK PERCEPTION AND TRANSMISSION POTENTIAL OF NEOSPORA CANINUM ON THE MINNESOTA LANDSCAPE

• Sponsoring Institution: State Agricultural Experiment Station
• Project Status: TERMINATED
• Funding Source: STATE
• Reporting Frequency: Annual
• Accession No.: 1003110
• Project No.: MIN-62-046
• Project Start Date: May 20, 2014
• Project End Date: Jun 30, 2016

Project Director
Minicucci, LA.

Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108

Performing Department
Veterinary Population Medicine

Non Technical Summary
Neospora caninum is a parasite that is best known for causing abortion in cattle and neurologic disease in dogs. It has a complicated life cycle with involvement from many animal species. Wild herbivores and wild canids are thought to act as intermediate and definitive hosts, respectively. Domestic dogs, coyotes, and gray wolves are all confirmed definitive hosts for N. caninum. Studies have shown that at least half the dairy and beef herds in the United States have one or more animals that have been exposed to Neospora. In an infected herd, up to 30 percent of the animals may test positive, and some cows may abort several times. While the cow shows little to no effect of the parasite, it is lethal to fetuses from three months of gestation to term. Cattle can become infected by consuming feed or water contaminated with eggs from the parasite, or grazing on contaminated pastures. These eggs are shed in the feces of domestic dogs, coyotes, and wolves. These animals become infected by eating infected animals, placentas or fetuses. This disease is one of the major reasons farm dogs should not be allowed to eat aborted fetuses, fetal membranes, or dead calves.Recent work in Minnesota has begun to elucidate some data surrounding this disease in the state. In blood samples taken during depredation control trapping by USDA-Wildlife Services in 2004, 8/11 (73%)adult wolves from five counties tested positive for N. caninum. Further, three northwestern Minnesota beef herds that had wolf predation, tested their herds, and documented N. caninum infections in 2005. In 2010, the Minnesota Department of Natural Resources began monitoring the prevalence of various diseases and parasites in wolves, including Neospora. To date, serum samples from 239 wolves throughout MN wolf range indicate a prevalence of 54% for N. caninum. In addition to wolves, domestic canids, fox, and coyote have tested positive for Neosporosis, although prevalence in these species is unknown in Minnesota. Other free-ranging wildlife, including white-tailed deer have been found to be seropositive. For example, in northwestern Minnesota, 44/62 (71%) of deer tested showed evidence of exposure to Neospora caninum.An estimate of the economic impact of this disease in Minnesota cattle herds is not readily available, largely due to an inability to describe the disease burden in the population. However, on an affected farm, several factors would be expected to contribute to the economic burden. These would include abortion rates, stillbirths and neonatal mortality, infertility, increased culling, decreased milk production, and decreased value of breeding stock. In epidemic herds, abortion rates as high as 57% have been reported. Recent concerns have been raised by both Minnesota legislators and Minnesota cattlemen regarding the potential challenges associated with Neosporosis and wolves. In particular, as the management of wolves is moved from the federal government to the state government, there is interest in how new management strategies may impact incidence of this disease. Informed scientific data is needed to better answer these questions in an effort to appropriately inform policy-making.This project aims to collect information about the diverse animal species involved in Neospora transmission through sample collection and testing. When possible, disease prevalence will be calculated. An on-farm risk assessment will be completed on ten farms as part of a pilot study to evaluate the effectiveness and feasibility of the tool. Additionally, surveys will be distributed to veterinarians and producers in Minnesota to gauge their perceptions about Neospora to aid future educational efforts. This work will also help to guide economic analyses surrounding this disease and inform the development of disease transmission models to evaluate risk.

Animal Health Component

100%

Research Effort Categories

Basic

0%

Applied

100%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
135	0830	1070	10%
311	0830	1103	10%
311	0830	1170	10%
311	3310	1103	10%
311	3310	1170	10%
311	3410	1103	10%
311	3410	1170	10%
311	3830	1103	10%
311	3830	1170	10%
311	4050	1070	10%

Knowledge Area
135 - Aquatic and Terrestrial Wildlife; 311 - Animal Diseases;

Subject Of Investigation
4050 - Protozoa; 3310 - Beef cattle, live animal; 0830 - Wild animals; 3830 - Pets (companion animals); 3410 - Dairy cattle, live animal;

Field Of Science
1103 - Other microbiology; 1070 - Ecology; 1170 - Epidemiology;

Keywords

neospora caninum

neosporosis

cattle

dogs

wildlife

wolves

risk factors

disease transmission

abortion

perceptions

management practices

prevalence

economic impact

Goals / Objectives
The goal of this pilot project aims to determine the impact of Neospora caninum across populations on the Minnesota landscape. Specific objectives: To accomplish the above stated goal, multiple objectives will be addressed. 1) What is the prevalence of Neospora caninum within select Minnesota cattle herds? 2) What is the prevalence of Neospora caninum in farm dogs, wolves, and coyotes? 3) What other wildlife reservoirs should be considered in Neospora transmission? 4) What is the knowledge base and attitudes of producers and veterinarians surrounding this disease? 5) What variables would be needed and what data could be collected to model transmission of Neospora caninum in the state? 6) What is the economic impact of the disease in the state?

Project Methods
Evaluation of diagnostic laboratory dataThe Veterinary Diagnostic Laboratory (VDL) currently offers testing for Neospora caninum in cattle utilizing both an ELISA-based serology test and an immunohistochenistry (IHC) based tissue test. Initial information can be gathered from the VDLdatabase by summarizing the number of test requests, the number of positive tests obtained, and characterization of both submissions and positive samples by region, time of year, and age of animal. This information will be used to guide the selection of farms for pilot study participation as well as teh time of year to sample.Prevalence pilot study on farms assessing disease exposure in cattle, dogs, and surrounding wildlife:Ten farms will be identified as pilot sites, representing different regions of the state and different production methods. Visits will be made to each farm once to collect blood samples from cattle (50 animals) and domestic canids (all dogs on farm if possible). Cattle blood samples will be tested at the UMN-VDL and canine samples will be tested at the University of California - Davis. Convenience fecal samples from wildlife and domestic canids will be collected for analysis at the ARS Parasitology Lab. An on-farm assessment will be administered to the producer and/or the veterinarian to assess disease history onthe farm, management strategies for dogs and cattle, interaction with local wildlife, and prevention practices. Focused wildlife samples will be collected in proximity to identified farms. Samples will be obtained through a combination of trapping, convenience sampling, and hunter samples. The project will collect a representative sample of animals with a particular focus on wild canids, mustelids, and raccoons. Heart, brain, serum, and feces will be collected from trapped/hunted animals and submitted to the ARS Parasitology Lab for testing using previously published methods.Producer and Veterinarian Surveys:Two independent but comparative surveys will be developed to measure the human dimensions issues regarding N. caninum; one for cattle producers and one for veterinarians. Topics to be addressed on the survey include: knowledge of N. caninum, estimates of diagnostic rates/samples submitted, current management and prevention, and beliefs about transmission methods. Additionally, evaluation of the willingness to implement prevention measures will be assessed. These surveys will be mailed to Minnesota veterinarians and a random sample of Minnesota beef and dairy producers. Survey data will be summarized and analyzed using EpiInfo.Economic analysis utilizing pilot data, published literature, and state statistics: Based on data collected in the first three components of this pilot study, a preliminary economic analysis will be conducted to evaluate the economic effects of Neospora caninum on Minnesota agriculture and determine what additional information is needed to better assess the economic impact. Data collected in the pilot will also inform which hosts to use in a multihost Susceptible-Exposed-Infectious model in the next stages of this investigation.

Progress 05/20/14 to 06/30/16

Outputs
Target Audience:During the final year of the project, researchers at the University of Minnesota, students and veterinary residents, biologists at the Minnesota Department of Natural Resources, and researchers at USDA Agricultural Research Services collaborated to compile project data and draft publications to be shared with the scientific community. The ten cattle farms that were involved in risk assessment were provided with final project reports summarizing their animal and environmental testing results as well as their risk scores. These reports were also shared with herd veterinarians. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has provided detailed individual reports to the ten participating farms not only summarizing test results, but also providing a risk score for Neosporosis and resources to manage the disease. Upon completion of data analysis and publication of the results, information can be presented at professional meetings for veterinarians and published in lay publications for cattle producers. Several veterinary public health residents and veterinary students participated in the project providing essential training in field work, sample collection, survey design, client communication, and data analysis. How have the results been disseminated to communities of interest?As previously stated, individual farm results and reports have been provided to participating cattle producers. The research team is completing final data analysis and drafting the manuscript summarizing the results of this work. It is anticipated that the final work will be submitted for publication in 2017. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? In relation to the goals described above, the following accomplishments have been achieved: 1) The in-herd prevalence for Neospora caninum was estimated for the ten study herds. While these numbers provide important information for exposure rates in herds, it is difficult to extrapolate our findings to provide an estimated prevalence in the state of Minnesota. 2) A convenience sample of canine blood was collected to estimate exposure to Neospora caninum among domestic dogs on farms. Wildlife samples were obtained based on trapping success. Few coyote samples were obtained, so it will be difficult to determine a disease prevalence in this species. Previous data collected by the Minnesota Department of Natural Resources details prevalence rates in wolves, and this data will be utilized to assess wildlife prevalence in proximity to farms. 3) Over 40 wildlife samples were collected and tested for Neospora caninum as part of this project. This work was able to document exposure to this parasite in many wildlife species which has implications for disease management, sentinel surveillance, and future research. 4) Surveys were completed by both cattle producers and veterinarians which provided essential information about Neosporosis knowledge, beliefs, and practices among these populations. This information will be utilized to guide future educational initiatives. 5) The data collected from this study will be shared with disease modellers to evaluate the possibility of future work to model this disease in the state. 6) No economic analysis has been conducted to date. The small sample involved in this study may prevent such a formal analysis from occurring due to limited data.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: J Eukaryot Microbiol. 2016 Sep;63(5):567-71. doi: 10.1111/jeu.12301. Epub 2016 Mar 2. Antibody Detection and Molecular Characterization of Toxoplasma gondii from Bobcats (Lynx rufus), Domestic Cats (Felis catus), and Wildlife from Minnesota, USA. Verma SK, Minicucci L, Murphy D, Carstensen M, Humpal C, Wolf P, Calero-Bernal R, Cerqueira-C�zar CK, Kwok OC, Su C, Hill D, Dubey JP.

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:During this reporting period, dairy and beef producers involved in the pilot study were visited for sample collection and completion of on-farm risk assessments. Laboratory partners at the Minnesota Veterinary Diagnostic Laboratory as well as USDA Agricultural Research Service were engaged for laboratory testing and diagnostics. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?1) Individual producer reports will be completed and shared with participating farms. The reports will share test results for each farm as well as a discussion of the farm risk category with specific recommendations to reduce risk. 2) Data analysis will be completed including a final summary of survey data. 3) Work will be summarized for publication as well as for education to interested producer and veterinary groups.

Impacts
What was accomplished under these goals? This project has been able to demonstrate that multiple species have exposure to Neospora caninum including cattle, other domestic animals such as cats and dogs in addition to a multitude of wildlife species. This information has implications on disease management strategies and further avenues for research. Regarding accomplishments within the project goals: 1) Neospora serology testing was performed on select cattle herds in the pilot project which has allowed for the estimation of prevalence rates within these herds. 2) Farm dogs were tested for evidence of exposure to Neospora. Previously collected wolf data will be used to make comparisons to findings in domestic species. 3) Over 40 wildlife samples were collected with demonstrated exposure to Neospora documented in multiple species.

Publications

Progress 05/20/14 to 09/30/14

Outputs
Target Audience: This project aims to reach multiple target audiences as study participants, collaborators, and stakeholders. During the reporting period, collaborations were arranged with the Minnesota Department of Natural Resources for sample collection and testing. Additionally, USDA-Wildlife Services has assisted in sample collection. Dairy and beef producers as well as large and mixed-animal veterinarians were contacted and requested to participate in the survey aspect of the project. The Minnesota Board of Animal Health, the Minnesota Department of Agriculture, the Minnesota Veterinary Medical Association, and the American Association of Bovine Practitioners were instrumental in helping to provide contacts for survey distribution. Local veterinary practices were contacted top aid in farm recruitment for the pilot project. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? During the next reporting period, sample testing will be completed. Additionally, all data analysis will be completed. The results from sample testing and data analysis will allow for study objectives to be addressed.

Impacts
What was accomplished under these goals? Project Goals - Accomplishments: What is the prevalence of Neospora caninum in select Minnesota cattle herds? VDL data was compiled to look at seasonal and regional differences in Neospora testing and results. No specific trends were identified, however, Neospora, as a percentage of submitted abortions, has decreased since 2002. Blood samples were collected from 10 cattle farms for serology testing. What is the prevealence of Neospora caninum in farm dogs, wolves, and coyotes? Only one coyote was trapped as part of the wildlife sampling, but multiple other species of interest were collected for testing: raccoons (22), skunks (7), and fox (2). Sample testing is pending. Blood from farm dogs was collected when available at the 10 pilot farms. A total of 14 samples were collected for testing. Blood results are pending. Additionally, convenience canine fecal samples (10) were collected and evaluated for Neospora. No fecal samples tested positive for Neospora oocysts. What other wildlife reservoirs should be considered in Neospora transmission? As indicated above, all animals trapped as part of the Wildlife Services effort on the 10 pilot farms will be evaluated for Neospora infection and antibodies. Samples to be evaluated were collected from coyotes, raccoons, skunks, fox, badgers, rabbits, oppossum, woodchuck, and bobcat. What is the knowledge base and attitudes of producers and veterinarians surrounding this disease? A KAP survey was designed and approved for distribution to both beef and dairy producers as well as large and mixed-animal veterinarians. Surveys were distributed to 1000 producers and approximately 500 veterinarians. Data is being entered in an Epi-Info database for analysis. What variables would be needed and what data could be collected to model transmission of Neospora caninum? Data collection from all aspects of this project and future analysis will help to inform this objective. Data collection is nearing completion for the on-farm risk assessment, producer and veterinarian surveys, and animal diagnostic samples. What is the economic impact of the disease in the state? No work has been done to date on this objective as data analysis will be used to inform this question.

Publications