External Parasites II & Blood parasites

The Rocky Mountain Wood tick Dermacentor andersoni occurs in West Nebraska and Northern Canada

The "American dog tick" Dermacentor variabilis is found allover North America, except in the Rocky Mountains. Both Dermacentor andersoni and Dermacentor variabilis are the chief vectors of Rickettsia rickettsii and tick paralysis in livestock.

Dermacentor occidentalis "the Pacific Coast tick" is restricted to the Pacific lowlands.

Ixodes scapularis "the black-legged tick" commonly parasitizes livestock in the southern U.S. is the intermediate host of Lymes disease.

• Rhipicephalus sanguineus the "kennel tick or brown dog tick", has traveled worldwide. It is the most common tick of dogs in the U.S. Is the vector for Babesia canis, Ehrlicha canis and Rickettsia sp.
• Note: Rhipicephalus sanguineus is also associated with the spreading of Leishmaniasis (not just the sand fly anymore).

A split screen of Otobius megnini the "spinose ear tick" and Otobius megnini in an ear canal.

The family Dermanyssidae contains Dermanyssus gallinae the "red-feather mite" of poultry, pigeon, and wild birds. It causes anemia and death in birds.

Demodex canis is an elongated mite which infests dogs worldwide, causing skin lesions and reactions.

Cheyletiella parasitivorax "walking dandruff' is the fur mite of rabbits

Family Sarcoptidae contains the most familiar mite Sarcoptes scabiei.

Sarcoptes scabiei lesion on a pig

Sarcoptes scabiei lesion on a dog's ear

Notoedres cati "feline scabies" lesions most commonly see in domestic cats.

Psoroptes sp. are larger than Sarcoptes sp. and have longer legs. Sheep Scabies leads to degeneration in the fleece quality and quantity.

Otodectes sp. ear mite in dogs and cats

Haemobartonella canis (Mycoplasma haemocanis) - long chains on the surface of RBCs. This organism may become apparent when the spleen is diseased (lymphosarcoma) or following spleenectomy XIOOO

Haemobartonella canis (Mycoplasma haemocanis) (protozoan) - in blood from splenectomized dog. X 1000

RBCs containing the protozoan Babesia canis Xl800

Dirofilaria immitus XlOOO

Haemobartonella felis (Mycoplasma haemofelis) - cocci or rods at the margin of the RBCs.

Haemobartonella felis (Mycoplasma haemofelis) in blood from cat with Feline Infectious Anemia, seen on the surface and at the margins of erythrocytes. Round deeply stained Howell-Jolly bodies on the RBC in center area. Xl8000

Toxoplasma gondii - cyst in a blast cell from the bone marrow of a cat in their terminal phase of erythroleukemia Xl800

A morulae of Ehrlichia equi in neutrophils in the blood of a horse stained with New Methylene blue stain.

Four morulae of Ehrlichia equi in neutrophils in the blood of a horse

Babesia caballi - numerous tear drop shaped organism in erythrocyte of a horse.

Trypanosoma congolense - from a horse of Kenya, East Africa XIOOO

Anaplasma marginale - in bovine blood appearing as round deeply stained structures in eccentric positions.(arrows) Also, Eperythrozoon wenyonii appearing as faintly stained objects on surface of the margins of several RBCs. Xl800

Eperythrozoon wenyonii - in center (arrow) and on the margin of RBC. Compare to more deeply stained Anaplasma marginale located inside and at the margins of 2 RBCs. X1800