1. Rickettsial Diseases 4-H Veterinary Science Extension Veterinary Medicine Texas AgriLife Extension Service College of Veterinary Medicine and Biomedical Sciences Texas A&M System http://aevm.tamu.edu

2. Objectives Discuss arthropod transmission of rickettsiae Describe a rickettsial disease of cattle Decribe a rickettsial disease of swine Describe a rickettsial disease of horses Describe two rickettsial diseases of dogs

3. Review Infectious diseases Bacterial diseases Viral diseases Fungal diseases Parasitic diseases Rickettsial diseases

4. Infectious -

5. Rickettsiae Definition A genus of small, rod-shaped, round to pleomorphic microorganisms in the order Rickettsiales. They are true bacteria, gram- negative, and cultivable only in living tissues. Transmitted by lice and ticks, they cause disease in humans and domestic animals but are also found in the cytoplasm of tissue cells of lice, fleas, ticks and mites, which may act as reservoirs and vectors

6. Symptoms Fever Anemia Edema Icterus (jaundice) Hemorrhages of mucous membranes Enlarged spleen Death

7. Acute Young animals Summer during vector season Chronic Older animals Stressful events

8. Transmission Biological Examples  Ticks  Sucking lice Live inside arthropods for months Mechanical Examples  Biting flies  Instruments  Blood transfusions Live short time outside of host

9. Types

10. Anaplasmosis (Gall sickness) Affects ruminants Transmission Mechanical  Horseflies  Deerflies  Instruments  Ticks Non-contagious Treatable Prevention Vaccinate Biosecurity

11. Eperythrozoonosis (Epe) Affects swine Transmission Mechanical and biological Sucking lice Instruments Prevention is best treatment

13. Ehrilichiosis (Tick fever) Affects Dogs Transmission Brown dog tick Instruments Blood transfusion

14. Rocky mountain spotted fever Affects Dogs Transmission American god tick Instruments Blood transfusion

15. Ehrlichiosis Affects Horses Transmission Unknown

16. Diagnosis Blood smears Anaplasma Eperythrozoon Ehrlichia rickettsial Serological Rocky mountains spotted fever