Related Experiment Videos
Bleeding diathesis associated with variant von Willebrand factor in a Simmental calf
P S Sullivan1, S T Grubbs, T W Olchowy
1Department of Animal Science, College of Veterinary Medicine, University of Tennessee, Knoxville 37901-1071.
Journal of the American Veterinary Medical Association
|December 15, 1994
Summary
A Simmental heifer diagnosed with variant von Willebrand disease experienced bleeding due to abnormal von Willebrand factor (vWF) structure. Plasma infusion corrected the bleeding disorder, indicating a potential treatment for this inherited condition.
Area of Science:
- Veterinary Medicine
- Hematology
- Genetics
Background:
- Von Willebrand disease (vWD) is an inherited bleeding disorder affecting multiple species.
- Simmental cattle are known to have a higher prevalence of certain genetic conditions.
Observation:
- A 10-month-old Simmental heifer presented with epistaxis, aural hematomas, and hemarthrosis.
- Initial tests showed normal clotting times but prolonged bleeding and poor platelet adhesion.
- Clinical signs resolved after bovine plasma infusion.
Findings:
- The affected heifer had a truncated multimeric structure of von Willebrand factor (vWF) and low vWF activity.
- Impaired platelet aggregation was observed in response to adenosine diphosphate.
- vWF concentration was normal, suggesting a qualitative defect rather than quantitative deficiency.
Implications:
- This case suggests a variant form of von Willebrand disease in Simmental cattle.
- Understanding this condition is crucial for cattle breeding and management.
- Further research is needed to clarify the relationship between this variant vWD and known Simmental cattle thrombopathies.