Systemic alterations of bovine hemostasis due to Rhipicephalus (Boophilus) microplus infestation
J Reck1, M Berger, R M S Terra
1Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, P. O. 15005, 91501-970 Porto Alegre, RS, Brazil.
Research in Veterinary Science
|June 24, 2008
Summary
Cattle infested with Rhipicephalus (Boophilus) microplus ticks experience significant disruptions in their hemostatic system. These tick infestations impair blood clotting and platelet function, impacting overall cattle health.
Area of Science:
- Veterinary Parasitology
- Hemostasis and Thrombosis
- Cattle Immunology
Background:
- Rhipicephalus (Boophilus) microplus is a significant ectoparasite in cattle breeding, causing economic losses.
- Tick saliva contains molecules that interfere with blood coagulation, but systemic host effects are not well-understood.
- Understanding host hemostatic system alterations is crucial for managing tick infestations.
Purpose of the Study:
- To investigate if Rhipicephalus (Boophilus) microplus infestation causes systemic disturbances in the host's hemostatic system.
- To quantify changes in coagulation parameters and platelet counts during experimental tick infestation.
Main Methods:
- Experimental infestation of six calves with 20,000 Rhipicephalus (Boophilus) microplus larvae.
- Blood collection at baseline and at 7, 14, and 21 days post-infestation.
- Analysis of collagen and ADP-induced platelet aggregation, activated partial thromboplastin time (aPTT), prothrombin time (PT), platelet count, and fibrinogen levels.
Main Results:
- Significant decrease in collagen and ADP-induced platelet aggregation in infested bovines.
- Reduced activated partial thromboplastin time (aPTT) and prothrombin time (PT), indicating impaired coagulation.
- Increased platelet blood count and fibrinogen levels, suggesting a compensatory host response.
Conclusions:
- Rhipicephalus (Boophilus) microplus infestation induces significant alterations in the bovine hemostatic system.
- The host's compensatory mechanisms appear insufficient to fully counteract the tick's anti-hemostatic effects.
- These hemostatic disturbances may contribute to the overall health impact of tick infestation in cattle.
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