This study represents an analysis of serological and risk factor data collected
previously in Alberta, Canada, involving neosporosis in beef and dairy cattle. The
causative agent of neosporosis, Neospora caninum (NC), is a single-celled,
apicomplexan protozoan parasite in which domesticated dogs have been identified as the
definitive host. The primary economic impact involves beef and dairy cattle due to
associated abortions and neonatal mortality. The data used in this study were collected
for cattle in both dairy and beef herds in an identical manner permitting a direct
comparison of host-, herd-, and environmental risk factors for neosporosis among beef
and dairy cattle using descriptive statistical methods and the construction of
multivariable models. The outcome assessed in the multivariable models was cow-level
seropositivity for antibodies to N. caninum. Individual-level fixed, herd-level fixed, and
random effects were evaluated with respect to the outcome. In the final multivariable
models, there were few statistically significant potential risk factors identified. In the
beef multivariable model, the significant explanatory factors were related to acreage of
farm, site of calving, and pH of soil. Among the potential risk factors identified in the
three multivariable models it appeared seropositivity to NC among beef cattle is more
related to environmental conditions; on the other hand, it seems that seropositivity to NC in dairy cattle pertains to associated management factors. In the future, longitudinal
studies are needed to explore the validity of the current knowledge regarding N. caninum
by investigating potential risk factors that have been identified due to the fact that crosssectional
studies can not prove association.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-3168 |
| Date | 15 May 2009 |
| Creators | Dietz, Mark Colton |
| Contributors | Scott, H. Morgan |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Thesis, text |
| Format | electronic, application/pdf, born digital |
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