Theileria parva: A protozoan parasite that is the etiologic agent of East Coast fever (THEILERIASIS). Transmission is by ticks of the Physicephalus and Hyalomma genera.Theileriasis: Infection of cattle, sheep, or goats with protozoa of the genus THEILERIA. This infection results in an acute or chronic febrile condition.Theileria: A genus of tick-borne protozoa parasitic in the lymphocytes, erythrocytes, and endothelial cells of mammals. Its organisms multiply asexually and then invade erythrocytes, where they undergo no further reproduction until ingested by a transmitting tick.Theileria annulata: A protozoan parasite causing tropical theileriasis in cattle. It is transmitted by ticks of the Hyalomma genus.Apicomplexa: A phylum of unicellular parasitic EUKARYOTES characterized by the presence of complex apical organelles generally consisting of a conoid that aids in penetrating host cells, rhoptries that possibly secrete a proteolytic enzyme, and subpellicular microtubules that may be related to motility.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Protozoan Vaccines: Suspensions of attenuated or killed protozoa administered for the prevention or treatment of infectious protozoan disease.Buffaloes: Ruminants of the family Bovidae consisting of Bubalus arnee and Syncerus caffer. This concept is differentiated from BISON, which refers to Bison bison and Bison bonasus.Rhipicephalus: A genus of TICKS, in the family IXODIDAE, widespread in Africa. Members of the genus include many important vectors of animal and human pathogens.Antigens, Protozoan: Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.Ticks: Blood-sucking acarid parasites of the order Ixodida comprising two families: the softbacked ticks (ARGASIDAE) and hardbacked ticks (IXODIDAE). Ticks are larger than their relatives, the MITES. They penetrate the skin of their host by means of highly specialized, hooked mouth parts and feed on its blood. Ticks attack all groups of terrestrial vertebrates. In humans they are responsible for many TICK-BORNE DISEASES, including the transmission of ROCKY MOUNTAIN SPOTTED FEVER; TULAREMIA; BABESIOSIS; AFRICAN SWINE FEVER; and RELAPSING FEVER. (From Barnes, Invertebrate Zoology, 5th ed, pp543-44)Genome, Protozoan: The complete genetic complement contained in a set of CHROMOSOMES in a protozoan.DNA, Protozoan: Deoxyribonucleic acid that makes up the genetic material of protozoa.Zambia: A republic in southern Africa, south of DEMOCRATIC REPUBLIC OF THE CONGO and TANZANIA, and north of ZIMBABWE. Its capital is Lusaka. It was formerly called Northern Rhodesia.Cattle Diseases: Diseases of domestic cattle of the genus Bos. It includes diseases of cows, yaks, and zebus.Antibodies, Protozoan: Immunoglobulins produced in a response to PROTOZOAN ANTIGENS.