Progress 07/01/00 to 12/31/03
Outputs
The four objectives of this project are as follows:1) Describe the seroepidemiology of Mycobacterium avium subspecies paratuberculosis (MAP) in cull dairy and beef cattle of Utah origin; 2) Compare the agreement between two MAP antibody detection tests (IDEXX ELISA, ImmuCell Tip-Test); 3) Estimate MAP herd prevalence in Northern Utah dairies; 4) Identify unique production and management practices that are associated with MAP infection in Northern Utah dairies. All project objectives have been completed. Objective 1: Serum samples from Utah cull dairy and beef cattle were collected and analyzed for MAP antibodies. The apparent seroprevalence of MAP in Utah cull dairy and beef cattle is 3.84% (42/1096) and 0.09% (1/1086), respectively. County seroprevalence rates are available upon request. Objective 2: Two MAP antibody detection tests were compared. There was a moderate level of agreement (Kappa = 0.48) between the IDEXX ELISA and the ImmuCell Tip-test. However, the two
MAP antibody detection tests gave statistically different results (P <0.05). These results suggest that the two tests should not be considered as similar for use in Johnes Disease control programs. Objective 3: Blood and fecal samples were collected from 86 dairy herds in Box Elder, Cache, and Weber counties representing almost 50% of the total cow population in Utah. Blood was collected from 30 randomly selected, 2nd lactation or older cows within each herd and analyzed for MAP antibody using the IDEXX ELISA test. Fecal samples were collected from MAP seropositive cows and cultured for a minimum of 16 weeks. Bacterial colonies were confirmed as MAP using both Zehl-Neelsen stain and PCR. A MAP positive herd was defined as one where MAP was definitively identified (by culture & PCR) from a cow within that herd. The apparent MAP herd prevalence in northern Utah dairies is 19.8% (true prevalence: 23.5-59.9%). Objective 4: A survey evaluating 82 aspects of herd production and management
was also completed during on farm sample collection by the herd owner. The relationship between these factors and MAP positive herds was evaluated using multiple regression analysis. Dairy herds that had purchased heifers or cows within the last five years were 40 times more likely to be MAP positive compared to herds that did not purchase heifers or cows or just purchased bulls. Jersey herds were 2.8 times and mixed breed herds were 14.7 times more likely to be MAP positive compared to Holstein herds. Herds that shared a common fence line between 2-6 month old calves were 12.3 times more likely to be MAP positive compared to those which did not share a common fence line. These data suggest that Johnes Disease is common in Utah dairy herds, particularly in herds that purchase heifers/cows and that true MAP prevalence is higher among Jersey and mixed breed herds compared to Holstein herds. The data also suggest buying bulls and showing cattle are not risk factors for MAP in Utah
herds.
Impacts
MAP infection in cattle causes a chronic, debilitating, and production limiting condition in cattle referred to as Johnes Disease. The information in this study demonstrates that Johnes Disease is common in Utah dairy herds and much more common in herds with certain characteristics. The results from this study will be used to help educate Utah cattlemen about Johne's Disease and to promote and direct efforts of a Utah state Johnes Disease control program.
Publications
- No publications reported this period
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Progress 01/01/02 to 12/31/02
Outputs
The objectives of this project are to describe the seroepidemiology of Mycobacterium avium subspecies paratuberculosis (MAP) in Utah cull dairy and beef cattle and to compare the agreement between two MAP antibody detection tests. Two additional objectives have been added to this project. The additional objectives are to estimate MAP prevalence in Northern Utah dairy herds and to identify unique production and management practices that are associated with MAP infection in Northern Utah dairies. The original project objectives have been completed. Serum samples from Utah cull dairy and beef cattle have been collected and frozen. Serum samples were analyzed for MAP antibodies using the IDEXX ELISA MAP antibody test kit. The Utah county of origin was successfully determined for 758 dairy cattle and 686 beef cattle to estimate the seroprevalence of MAP within each Utah county. The results of two MAP antibody detection tests (IDEXX ELISA and ImmuCell Tip-Test) were also
compared using 162 serum samples. A study to complete two additional objectives was initiated in 2002. One hundred dairy herds in Box Elder, Cache, and Weber counties were randomly selected for MAP evaluation. A survey to evaluate 82 aspects of herd production and management practices was generated. The following information will be collected from each dairy farm. Blood will be collected from 30 randomly selected cows 3 years old or older and tested for MAP specific antibody. If a cow is blood test positive for MAP antibody, a fecal sample will be collected from that cow and cultured for the MAP organism. Fecal culture results will be used to classify a dairy herd as MAP positive. Herd production and management practices survey data will be collected from the herd owner or herdsperson. Thus far, 4 dairy herds from Northern Utah have been enrolled and tested using the above protocol. The seroprevalence of MAP in Utah cull dairy and beef cattle is 3.84% (42/1096) and 0.09% (1/1086)
respectively. There was a moderate level of agreement (Kappa = 0.48) between the IDEXX ELISA and the ImmuCell Tip-test. However, the two MAP antibody detection tests gave statistically different results (P <0.05). The tests specifically varied in the identification of a positive test result. The seroprevalence data suggest that the prevalence of Johne's disease (infection with MAP) in Utah cull dairy and beef cattle is comparable with other slaughterhouse based surveys of Johne's disease within the United States. This underscores the need for a Johne's disease control program in Utah which may help prevent the spread of the disease and alert and educate Utah cattlemen and veterinarians about this disease. The results from the comparison between the IDEXX ELISA and ImmuCell Tip-Test suggest that the two tests should not be considered as similar for use in Johne's disease control programs. These data also suggest that the ImmuCell Tip-Test may underestimate the level of Johne's disease
infection within a herd as compared to the IDEXX ELISA.
Impacts
Infection by Mycobacterium avium subspecies paratuberculosis (MAP) may cause a chronic, debilitating, and production limiting condition in cattle referred to as Johne's disease. The information in this study will be used to help educate Utah cattlemen about Johne's disease and to promote a Utah state Johne's disease control program.
Publications
- No publications reported this period
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Progress 01/01/01 to 12/31/01
Outputs
The objective of this project is to describe the seroepidemiology of Mycobacterium avium subspecies paratuberculosis (MAP) in cull dairy and beef cattle of Utah origin and to compare the agreement between two MAP antibody detection tests (IDEXX ELISA, ImmuCell Tip-Test). Serum samples from Utah cull dairy (n = 1500) and beef (n = 1500) cattle have been collected and frozen. Serum samples (n = 1096,dairy; n = 1086, beef) were analyzed for MAP antibodies as a single lot using the IDEXX ELISA Mycobacterium paratuberculosis antibody test kit. All serological testing was performed in my laboratory (HRB) after successfully completing the National Veterinary Services Laboratories (Ames, IA) certification test for running the Johne's IDEXX ELISA test. The Utah county of origin was successfully determined for 758 dairy cattle and 686 beef cattle to estimate the seroprevalence of MAP within each Utah county. The results of two MAP antibody detection tests (IDEXX ELISA and
ImmuCell Tip-Test) were also compared using 162 serum samples. The seroprevalence of MAP in Utah cull dairy and beef cattle is 3.84% (42/1096) and 0.09% (1/1086) respectively. Estimates of MAP seroprevalence in cull dairy and beef cattle have also been calculated for each Utah county but available space in this report prohibits reporting those data here. However, individual Utah county MAP seroprevalence estimates are available in a table or geographical map form upon request. There was a moderate level of agreement (Kappa = 0.48) between the IDEXX ELISA and the ImmuCell Tip-test. However, the two MAP antibody detection tests gave statistically different results (P <0.05). The tests specifically varied in the identification of a positive test result. Forty-six serum samples (n = 162) were classified as MAP positive by the IDEXX ELISA. The ImmuCell Tip-Test classified 54.3% (25/46) of the IDEXX ELISA positive serum samples as positive for MAP antibodies. The seroprevalence data suggest
that the prevalence of Johne's disease (infection with MAP) in Utah cull dairy and beef cattle is comparable with other slaughterhouse based surveys of Johne's disease within the United States. This underscores the need for a Johne's disease control program in Utah which may help prevent the spread of the disease and alert and educate Utah cattlemen and veterinarians about this disease. The results from the comparison between the IDEXX ELISA and ImmuCell Tip-Test suggest that the two tests should not be considered as similar for use in Johne's disease control programs. These data also suggest that the ImmuCell Tip-Test may under estimate the level of Johne's disease infection within a herd as compared to the IDEXX ELISA. Several presentations on the research results have been given by Dr. Bingham. A manuscript containing these data will be submitted for publication within the next year.
Impacts
Infection by Mycobacterium avium subspecies paratuberculosis (MAP) may cause a chronic, debilitating, and production limiting condition in cattle referred to as Johne's disease. The information in this study will be used to help educate Utah cattlemen about Johne's disease and to promote a Utah state Johne's disease control program.
Publications
- Bingham HR, Young SK, Bagley CV, et al. Seroprevalence of Mycobacterium avium subspecies paratuberculosis in Utah cull dairy cows. 82nd Annual Conference of Research Workers in Animal Diseases 2001;No. 33.
- Bingham HR, Young SK, Bagley CV. A comparison between two commercially available Mycobacterium avium subspecies paratuberculosis antibody test kits. 82nd Annual Conference of Research Workers in Animal Diseases 2001;No. 32.
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Progress 01/01/00 to 12/31/00
Outputs
The objective of this project is to describe the seroepidemiology of Mycobacterium avium subspecies paratuberculosis (MAP) in cull dairy and beef cattle of Utah origin. The project is currently in the data collection phase. The sampling objective of the project is to collect 3000 serum samples from cull dairy and beef cattle and subsequently identify the Utah county of origin for 2200 samples (n = 1100 dairy cattle; n = 1100 beef cattle). As of this writing, 1750 individual serum samples have been collected from cull dairy (n = 900) and beef (n = 950) cattle. The county of origin has been identified for 350 of the serum samples. After all serum samples and origin information have been collected, serum samples will be analyzed for antibody specific for MAP using both the ELISA and Johne's Tip-Test as a single lot. Descriptive data will be summarized and written for publication.
Impacts
Infection by Mycobacterium avium subspecies paratuberculosis (MAP) may cause a chronic, debilitating, and production limiting condition in cattle referred to as Johne's disease. The information in this study will be used to help educate Utah cattlemen on the subject of Johne's disease and to promote a Utah state Johne's disease control program.
Publications
- No publications reported this period
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