Progress 07/01/01 to 06/30/04
Outputs
The first aim of this project was to determine the spatial relationships of bovine TB (bTB) in white-tailed deer, relating to factors in the physical landscape and location-specific human activity. Spatial clusters of TB were detected in areas that encourage deer to congregate for long periods of time. One paper has been submitted for publication. To identify factors that may influence whether a cattle herd will develop TB, a matched case-control study of herds was conducted to identify herd management factors and environmental conditions associated with TB (Kaneene et al., 2002). A stochastic risk assessment model for herd TB status was developed, based on results of this study, and has been integrated with economic data to create a management tool to develop recommendations to reduce the TB risk for individual cattle farms. The on-farm program is undergoing field testing. The study on the effect of Johnes disease (JD) on the caudal fold tuberculin test (CFT) in herds
without TB was completed and submitted for publication. Fecal culture and antibody ELISA for M. avium ssp. paratuberculosis, were performed on cattle from 10 herds. Blood samples were taken and subjected to gamma-interferon (GI) tests for M. bovis and JD. Cattle positive for JD by fecal culture, ELISA, or GI appear to be more likely to be false + on CFT than were negative cattle, and no associations were found between + fecal culture or ELISA with GI for M. bovis. To determine the effectiveness of current TB testing in Michigan cattle, cattle from TB-infected herds were examined by gross necropsy, histopathologic exam, mycobacterial culture, and PCR. Bayesian inference was used to estimate the sensitivity and specificity of the CFT and comparative cervical tuberculin test (CCT) using two-population-two-tests latent-class models. Bayesian estimates of the sensitivity and specificity of the CFT and CCT were 85 and 94%, and 76 and 99%, respectively, which agrees with reports from other
studies in the U.S. Two papers have been submitted for publication. To evaluate the role of rodents as possible reservoirs of M. bovis, an experimental study was conducted to study the relative susceptibility of 'wild-type' rodents to inoculation with M. bovis by the oral and intranasal routes. M. bovis was cultured from the feces of 9 oral inoculates and 8 intranasal inoculates on day 1 post-inoculation, and from fecal samples of 3 intranasal inoculates at day 30 post-inoculation, and also from pooled tissue samples. Results of this study are being prepared for publication. In-person interviews were conducted with farm families to measure the social impacts of bTB, and study findings indicate that families can adapt to the changes imposed by the presence of TB on their farms, but they experienced problems in receiving information in a timely fashion, and inconsistency and inequity in the application of government policies and procedures. To lessen negative impacts, families should be
accorded more attention and consideration when policies are made, and should have a more substantial role in decision-making as it relates to their own farms. Two manuscripts are being submitted for publication.
Impacts
Control and eradication of TB from the Michigan livestock industry requires an understanding of the disease and how it spreads, efficient disease detection methods, and the development of tools for control of the disease at the farm level. Risk assessment models can be used to develop sound, cost-effective disease control programs. The reliability of the caudal fold skin test, used for TB testing in livestock, may be affected by an animal's disease or vaccination status. These factors should be taken into consideration when interpreting TB skin test results, or designing a TB surveillance program. Current TB tests require great time, effort and expense, and false results are common with existing skin and blood tests. Even with TB lesions, many times associated with acid-fast bacilli, bacteria cannot be cultured because of poor samples, freeze-thaw, or lack of available fresh tissues. New DNA-based testing methods (cDNA microarray analysis of gene expression and
laser-capture microscopy for isolating DNA for PCR) have the potential to become rapid, sensitive methods to identify TB in tissue samples in an efficient and reliable way. With a better understanding of the stresses and social impacts of bovine TB on Michigan farm families, programs can be designed to reduce the negative impact of TB control and surveillance programs on families' lives.
Publications
- Dunn, J.R., Kaneene, J.B., Grooms, D.L., Bolin, S.R., Bolin, C.A., Bruning-Fann, C.S. Testing positive for Mycobacterium avium subsp. paratuberculosis and the lack of significant effect on the caudal fold tuberculin (CFT) and gamma interferon tests for bovine tuberculosis. Am J Vet Res, accepted for publication 2004.
- Fitzgerald, S.D., Boland, K.G., Clarke, K.R., Wismer, A., Kaneene, J.B., Berry, D.E., Church, S.V., Hattey, J.A., C.A. Bolin. Experimental Inoculation of Mallard Ducks (Anas platyrhynchos) with Mycobacterium bovis. Avian Dis. submitted 2004.
- Griffore, R., Phenice, L. The Impact of Bovine TB on the Farm Family Ecosystem. In preparation for submission to Family Relations, 2004.
- Griffore, R., Phenice, L; Kaneene, J.B. Veterinarians: A Complex Role of Mediation Between the State and Farm Families. In preparation for submission to Journal of the American Veterinary Medical Association, 2004.
- Miller, R., Kaneene, J.B., Schmitt, S.M., Lusch, D.P., Fitzgerald, S.D. Geographic distribution and spatial analysis of Mycobacterium bovis infection in white-tailed deer (Odocoileus virginianus) in Michigan. Prev Vet Med. accepted 2004.
- Norby, B., Bartlett, P.C., Fitzgerald, S.D., Granger, L., Bruning-Fann, C., Whipple, D.L., J.B. Payeur. The Sensitivity of Gross Necropsy, Caudal Fold and Comparative Cervical Tests for the Diagnosis of Bovine Tuberculosis. J Vet Diagn Invest. 16:126-131, 2004.
- Norby, B., Bartlett, P.C., Grooms, D.L., Kaneene, J.B., Bruning-Fann, C.S. Herd-level sensitivity, specificity, and predictive values of bovine tuberculosis skin tests in Michigan. Am J Vet Res. submitted 2004.
- Norby, B. Tempelman, R.J., Hansonc, T.E., Kaneene, J.B., Bartlett, P.C. Estimation of sensitivity and specificity of bovine tuberculosis skin tests in Michigan when a perfect reference test is not available. Prev Vet Med. submitted 2004.
- O'Brien, D.J., Schmitt, S.M., Berry, D.E., Fitzgerald, S.D., Vanneste, J.R., Lyon, T.J., Church, S.V., Fierke, J.S., Schooley, A.M., Cooley, T.M., Magsig, D., Zwick, L., and B.V. Thomsen: Estimating the True Prevalence of M. bovis in Hunter-harvested White-tailed Deer in Michigan. J Wildl Dis. 40:42-52, 2004.
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Progress 01/01/03 to 12/31/03
Outputs
To complete the risk assessment for cattle herds developing TB in northeastern Michigan, a matched case-control study was conducted to identify herd management factors and environmental conditions associated with herd TB status. A predictive risk assessment model for herd TB status was generated from the results of this study, and is being integrated with an economic risk model for use on the farm to allow individual farmers to calculate their herd risk for TB. This on-farm program will provide epidemiologically and economically-based recommendations to reduce the TB risk for their farms. To determine whether the effectiveness of current TB testing may be influenced by the reliability of the caudal fold tuberculin test (CFT) in cattle, 494 cattle from 7 TB-infected herds were examined by gross necropsy, histopathologic exam, mycobacterial culture, and PCR, performed on samples that were histologically compatible for TB. Bayesian inference was used to estimate the
sensitivity and specificity of the CFT and the comparative cervical tuberculin test (CCT) using two-population-two-tests latent-class models. The Bayesian estimates and 95% intervals of the sensitivity and specificity of the CFT and CCT were 85% (56-97.5) and 94% (90-98), and 76% (47.5-93) and 99% (96-99), respectively. The estimates of sensitivity and specificity from this study generally agree with those reported from other studies in the United States. The study on the effect of Johnes disease on the CFT in herds without TB was completed. Fecal culture and antibody ELISA for M. avium ssp. paratuberculosis, the agent causing Johnes Disease, were performed on 1,043 cattle from 10 herds on day CFT read. Blood samples also taken and subjected to gamma-interferon tests for M. bovis and Johne's Disease. In these cattle, 180 (17%) were CFT suspects and 8 (.8%) gamma-interferon positive for M. bovis, 115 (11%) were positive for Johne's Disease by ELISA, 45 (4%) by culture, and 16 (2%) by
both culture and ELISA. Cattle positive for Johnes Disease by fecal culture, ELISA, or gamma-interferon appear to be more likely to be false positive on CFT than were negative cattle, and no associations were found between positive fecal culture or ELISA with gamma-interferon for M. bovis. In-person interviews have been conducted with farm families to measure the social impacts of bovine TB, both short- and long-term, and study findings indicate that farm families can adapt to the changes imposed by the presence of TB on their farms. Unfortunately, these families have experienced problems in receiving information in a timely fashion, and inconsistency and inequity in the application of government policies and procedures. To lessen negative impacts on these farm families, they should be accorded more attention and consideration when policies are made, and should have a more substantial role in decision-making as it relates to their own farms. The social impact of bovine TB and TB
eradication programs on farmers, residents and media in the TB area has been summarized and is being prepared for publication.
Impacts
Control and eradication of TB from the Michigan livestock industry requires an understanding of the disease and how it spreads, efficient disease detection methods, and the development of tools for control of the disease at the farm level. Risk assessment models can be used to develop sound, cost-effective disease control programs. The reliability of the caudal fold skin test, used for TB testing in livestock, may be affected by an animal's disease or vaccination status. These factors should be taken into consideration when interpreting TB skin test results, or designing a TB surveillance program. Current TB tests require great time, effort and expense, and false results are common with existing skin and blood tests. Even with TB lesions, many times associated with acid-fast bacilli, bacteria cannot be cultured because of poor samples, freeze-thaw, or lack of available fresh tissues. New DNA-based testing methods (cDNA microarray analysis of gene expression and
laser-capture microscopy for isolating DNA for PCR) have the potential to become rapid, sensitive methods to identify TB in tissue samples in an efficient and reliable way. With a better understanding of the stresses and social impacts of bovine TB on Michigan farm families, programs can be designed to reduce the negative impact of TB control and surveillance programs on families' lives.
Publications
- Diegel, K.L., Fitzgerald, S.D., Palmer, M.V., and D.L. Whipple: A Novel Cytologic Evaluation Technique for the Detection of Mycobacteria in Veterinary Samples. J. Appl. Res. Vet. Med. 1:37-44, 2003.
- Fitzgerald, S.D., Zwick, L.S., Berry, D.E., Church, S.V., Kaneene, J.B., and Reed, W.M. Experimental Inoculation of Pigeons (Columba livia) with Mycobacterium bovis. Avian Dis., 47:470-475, 2003.
- Fitzgerald, S.D., Zwick, L.S., Diegel, K.L., Berry, D.E., Church, S.V., Sikarskie, J.G., Kaneene, J.B., and Reed, W.M. Experimental Aerosol Inoculation of Mycobacterium bovis into North American Opossums (Didelphis virginiana). J. Wildl. Dis., 39(2): 418-423, 2003.
- Miller, R., Kaneene, J.B., Fitzgerald, S.D., Schmitt, S.M. Evaluation of the influence of supplemental feeding of white-tailed deer (Odocoileus virginianus) on the prevalence of bovine tuberculosis in the Michigan wild deer population. J. Wildl. Dis., 39(1):84-95, 2003.
- Kaneene, J.B., Thoen, C.O. Tuberculosis. J Am Vet Med Assoc. (invited paper, accepted 2003)
- Miller, R., Kaneene, J.B., Schmitt, S.M., Lusch, D.P., Fitzgerald, S.D. Geographic distribution and spatial analysis of Mycobacterium bovis infection in white-tailed deer (Odocoileus virginianus) in Michigan. Prev Vet Med. submitted 2003.
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Progress 01/01/02 to 12/31/02
Outputs
To identify factors that may influence whether a cattle herd will develop TB, a matched case-control study of cattle herds in the TB-affected area was conducted to identify herd management factors and environmental conditions associated with herd TB status (Kaneene et al., 2002). Herd biosecurity measures and levels of TB in wildlife in the area were among the factors found to influence herd risk for TB. A stochastic risk assessment model for herd TB status has been developed, based on results from this case-control study, and is being integrated with economic data to create a management tool to develop epidemiologically and economically-based recommendations to reduce the TB risk for individual cattle farms. The effectiveness of current TB testing may be influenced by the reliability of the caudal fold tuberculin test (CFT) in cattle, and the influence of other diseases, such as Johne's disease, on the reliability of TB skin tests. Cattle from 7 TB-infected herds
were examined by gross necropsy, histopathologic exam, mycobacterial culture, and polymerase chain reaction assay performed only on samples that were histologically compatible for TB. The sensitivities of the CFT, the CFT and comparative cervical tests used in series, and gross necropsy were 93.02%, 88.37%, and 86.05%, respectively. The sensitivities of the two skin tests were slightly higher when 2 or more lesions were detected by gross necropsy. Though sensitivities were high, two of the seven herds (29%) would have had one or more positive animals left in the herd if a test-and-removal program had been used, which would reduce the effectiveness of current TB control programs. When examining the effect of Johne's disease on the CFT in herds without TB, the total false positive rate on the CFT for 10 herds was 17.3%. The CFT false positive rate based on Johne's results were 38/128 of those ELISA-positive for Johne's disease only, 4/17 of those ELISA and culture positive for Johne's
disease, and 7/28 of those positive by culture only. High prevalence herds averaged 23.9% positive for Johne's and 20.9% positive on the CFT. The low prevalence herds averaged 7.8% positive for Johne's and 14.0% positive on the CFT. These results indicate a possible association between Johne's disease and a false positive CFT. The social impact of bovine TB and TB eradication programs on farmers, residents and media in the TB area has been examined. Interviews have been conducted with members of farm families, and patterns of the long-term impacts of bovine TB on families have been recorded. Preliminary results suggest that some families have considerable ability to adapt to circumstances associated with bovine TB. However, families do not receive information in a timely fashion, and face inconsistency and inequity associated with government policies and procedures. These findings indicate that farm families should be accorded more attention and consideration when policies are made
concerning bovine TB, and should have a more substantial role in decision-making as it relates to their own farms.
Impacts
Results of the risk analysis will indicate areas in which control measures can be implemented to reduce the spread of tuberculosis from wildlife to livestock and humans. These findings will also indicate areas where education and control programs are needed to safeguard the public. Results of these analysis will provide better estimates of the sensitivity and specificity of currently used TB skin testing methods in cattle, and indicate the extent to which cattle disease status, geography, and the presence of wildlife TB reservoirs influences the results of these tests. This information could be used to direct both the strategy and the tactics of the TB testing and control effort. Identification of areas of stress and negative social impact on farm families, and identification of needs as expressed by these families can form the basis for the development of social support programs to assist families affected by bovine tuberculosis, and these results can be used to
develop proactive programs to reduce the negative impact of tuberculosis surveillance and control programs on farm families in the future. Recognition of attitudes of residents and non-residents on the bovine tuberculosis situation, and communities affected by bovine tuberculosis, will provide information to use for educational programs to keep the public informed about the tuberculosis situation, and lessen any unnecessarily negative attitudes about the situation or affected communities.
Publications
- Diegel, K.L., Fitzgerald, S.D., Berry, D.E., Church, S.V., Reed, W.M., Sikarskie, J.G., and J.B. Kaneene: Experimental Inoculation of North American Opossums (Didelphis virginiana) with Mycobacterium bovis. J. Wildl. Dis. 38:275-281, 2002.
- Kaneene, J.B., Bruning-Fann, C., Dunn, J., Mullaney, T.P., Berry, D., Massey, J., Thoen, C.O., Halstead, S., Schwartz, K. Epidemiologic Investigation of Mycobacterium bovis in a population of cats. JAVMA, Vol. 63: 1507-1511, 2002.
- Kaneene, J.B., Bruning-Fann, C.S., Granger, L.M., Miller, R., Porter-Spalding, B.A. Environmental and farm management factors associated with tuberculosis on cattle farms in northeastern Michigan. JAVMA, Vol. 221: 837-842, 2002.
- Kaneene, J.B., VanderKlok, M., Bruning-Fann, C.S., Miller, R. The Prevalence of Mycobacterium bovis in Privately-Owned Cervid Ranches in Michigan. JAVMA, Vol. 220, No.5, 656-659, 2002.
- Miller, R., Kaneene, J.B., Fitzgerald, S.D., Schmitt, S.M. Supplemental feeding and bovine tuberculosis in Michigan white-tailed deer. Journal of Wildlife Diseases (in press, 2002).
- O'Brien, D.J., Schmitt, S.M., Fierke, J.S., Hogle, S.A., Winterstein, S.R., Cooley, T.M., Moritz, W.E., Butler, K.L., Fitzgerald, S.D., Berry, D.E., Kaneene, J.B. Epidemiology of Mycobacterium bovis in free-ranging white-tailed deer, Michigan, USA, 1995-2000. Prev. Vet. Med. 54:47-63, 2002.
- Palmer, M.V., Whipple, D.L., Butler, K.L., Fitzgerald, S.D., Bruning-Fann, C.S., and S.M. Schmitt: Tonsilar Lesions in White-tailed Deer (Odocoileus virginianus) Naturally Infected with Mycobacterium bovis. Vet. Rec. 151:149-150, 2002.
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Progress 01/01/01 to 12/31/01
Outputs
Project 1: Epidemiological study of Mycobacterium bovis in wild and domestic animals: The first specific aim of this project was to determine the spatial relationships of bovine TB in white-tailed deer, relating to factors in the physical landscape and location-specific human activity. To date, we have detected several spatial clusters of TB cases from 1995 to 1999, and preliminary analysis has indicated that these clusters are located in areas which encourage deer to congregate for long periods of time. Project 2: Risk analysis of bovine TB for surveillance and control programs: The specific aim of this project was to develop a risk assessment model of M. bovis infection in cattle and other livestock and captive cervids in Michigan. A matched case-control study of cattle herds in the TB-affected area was conducted to identify herd management factors and environmental conditions associated with herd TB status. Factors associated with increasing the risk of TB included
cattle housing areas or cattle feed on the farm more accessible or attractive to deer, such as the presence of ponds or streams in pastures. Factors which decreased the risk of TB were those which reduced deer access to cattle feed or cattle housing areas. Project 3: The effect of Mycobacterium paratuberculosis status on the reliability of the caudal fold tuberculin (CFT) test in cattle: The first specific aim was to compare results of the CFT from Johnes-positive cattle with results from Johnes-negative cattle, using the CCT (and mycobacterial culture if appropriate) for validation. Results to date showed that Johne's disease status did not affect results of CFT, and did not give false positives on the γ-interferon test, but false positives in the CFT were linked to other M. avium spp.. However, these results are based on findings from only two herds, and these results should be taken with this in consideration. Project 4: New epidemiologic approaches to estimate the rates of M.
bovis infection and false test results. The specific aims of this study were to construct probabilistic risk assessment models of the likely frequency distribution of the prevalence of bovine TB in different sub-populations of domestic ruminants. To date, the sensitivity of the CFT in TB-positive cattle herds has been found to be 93.3%, while the CFT/CCT used in series was 88.1%. Project 5: Evaluation of rodents as possible reservoirs of M. bovis: The specific aims of this project were to study the relative susceptibility of 'wild-type' rodents to inoculation with M. bovis by the oral and intranasal routes. Mycobacterium bovis was cultured from the feces of 9 oral inoculates and 8 intranasal inoculates on day 1 post-inoculation, and from fecal samples of 3 intranasal inoculates at day 30 post-inoculation, and also from pooled tissue samples.
Impacts
The basic information is critical for the development of risk assessment models for bovine TB in cattle, economic impact models, and cattle industry risk analyses. Specific management factors identified by this study will be used to develop farm TB control programs. Identification of these areas can be used to target locations and/or environmental conditions where control measures can be implemented to reduce bovine TB in wild white-tailed deer. Since opossums and voles can contribute to the spread of TB between and among wild and domestic animals, this information is important in the development of cattle farm biosecurity programs and TB risk analyses. Farm families facing bovine TB should be accorded more attention and consideration in decision-making related to their operation and governmental policy.
Publications
- O'Brien, D.J., Schmitt, S.M., Fierke, J.S., Hogle, S.A., Winterstein, S.R., Cooley, T.M., Moritz, W.E., Butler, K.L., Fitzgerald, S.D., Berry, D.E., Kaneene, J.B. Some epidemiologic aspects of Mycobacterium bovis in free-ranging white-tailed deer, Michigan, USA, 1995-2000. Preventive Veterinary Medicine. (in press, 2001).
- Butler, K.L., Fitzgerald, S.D., Berry, D.E., Church, S.V., Reed, W.M., Sikarskie, J.G., and J.B. Kaneene: Experimental Inoculation of North American Opossums (Didelphis virginiana) with Mycobacterium bovis. J. Wildl. Dis. (in press, 2001).
- Kaneene, J.B., Bruning-Fann, C.S., Granger, L.M., Miller, R. Porter-Spalding, B.A., O'Brien, D.J. A case-control study of bovine tuberculosis on Michigan cattle farms. Am. J. Vet. Res. (submitted, 2002).
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