Brucella ovis: A species of the genus BRUCELLA which are pathogenic to SHEEP.Brucella: A genus of gram-negative, aerobic bacteria that causes BRUCELLOSIS. Its cells are nonmotile coccobacilli and are animal parasites and pathogens. The bacterium is transmissible to humans through contact with infected dairy products or tissue.Brucellosis: Infection caused by bacteria of the genus BRUCELLA mainly involving the MONONUCLEAR PHAGOCYTE SYSTEM. This condition is characterized by fever, weakness, malaise, and weight loss.Brucella abortus: A species of the genus BRUCELLA whose natural hosts are cattle and other bovidae. Abortion and placentitis are frequently produced in the pregnant animal. Other mammals, including humans, may be infected.Epididymitis: Inflammation of the EPIDIDYMIS. Its clinical features include enlarged epididymis, a swollen SCROTUM; PAIN; PYURIA; and FEVER. It is usually related to infections in the URINARY TRACT, which likely spread to the EPIDIDYMIS through either the VAS DEFERENS or the lymphatics of the SPERMATIC CORD.Brucella melitensis: A species of the genus BRUCELLA whose natural hosts are sheep and goats. Other mammals, including humans, may be infected. In general, these organisms tend to be more virulent for laboratory animals than BRUCELLA ABORTUS and may cause fatal infections.Sheep Diseases: Diseases of domestic and mountain sheep of the genus Ovis.Actinobacillosis: A disease characterized by suppurative and granulomatous lesions in the respiratory tract, upper alimentary tract, skin, kidneys, joints, and other tissues. Actinobacillus lignieresii infects cattle and sheep while A. equuli infects horses and pigs.Brucella Vaccine: A bacterial vaccine for the prevention of brucellosis in man and animal. Brucella abortus vaccine is used for the immunization of cattle, sheep, and goats.Complement Fixation Tests: Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Anaplasma ovis: A species of gram-negative bacteria producing mild to severe ANAPLASMOSIS in SHEEP and GOATS, and mild or inapparent infections in DEER and CATTLE.Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Brucella canis: A species of gram-negative bacteria infecting DOGS, the natural hosts, and causing canine BRUCELLOSIS. It can also cause a mild infection in humans.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Brucellosis, Bovine: A disease of cattle caused by bacteria of the genus BRUCELLA leading to abortion in late pregnancy. BRUCELLA ABORTUS is the primary infective agent.Psoroptidae: Family of parasitic MITES, in the superfamily Sarcoptoidea, order Astigmata. Genera include Psoroptes and Chorioptes.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Sheep, Domestic: A species of sheep, Ovis aries, descended from Near Eastern wild forms, especially mouflon.