Lentivirus Infections: Virus diseases caused by the Lentivirus genus. They are multi-organ diseases characterized by long incubation periods and persistent infection.Lentivirus: A genus of the family RETROVIRIDAE consisting of non-oncogenic retroviruses that produce multi-organ diseases characterized by long incubation periods and persistent infection. Lentiviruses are unique in that they contain open reading frames (ORFs) between the pol and env genes and in the 3' env region. Five serogroups are recognized, reflecting the mammalian hosts with which they are associated. HIV-1 is the type species.Visna: Demyelinating leukoencephalomyelitis of sheep caused by the VISNA-MAEDI VIRUS. It is similar to but not the same as SCRAPIE.Pneumonia, Progressive Interstitial, of Sheep: Chronic respiratory disease caused by the VISNA-MAEDI VIRUS. It was formerly believed to be identical with jaagsiekte (PULMONARY ADENOMATOSIS, OVINE) but is now recognized as a separate entity.Immunodeficiency Virus, Feline: A species of LENTIVIRUS, subgenus feline lentiviruses (LENTIVIRUSES, FELINE) isolated from cats with a chronic wasting syndrome, presumed to be immune deficiency. There are 3 strains: Petaluma (FIP-P), Oma (FIP-O) and Puma lentivirus (PLV). There is no antigenic relationship between FIV and HIV, nor does FIV grow in human T-cells.Visna-maedi virus: A species of LENTIVIRUS, subgenus ovine-caprine lentiviruses (LENTIVIRUSES, OVINE-CAPRINE), that can cause chronic pneumonia (maedi), mastitis, arthritis, and encephalomyelitis (visna) in sheep. Maedi is a progressive pneumonia of sheep which is similar to but not the same as jaagsiekte (PULMONARY ADENOMATOSIS, OVINE). Visna is a demyelinating leukoencephalomyelitis of sheep which is similar to but not the same as SCRAPIE.Feline Acquired Immunodeficiency Syndrome: Acquired defect of cellular immunity that occurs in cats infected with feline immunodeficiency virus (FIV) and in some cats infected with feline leukemia virus (FeLV).Lentiviruses, Ovine-Caprine: A subgenus of LENTIVIRUS comprising viruses that produce multi-organ disease with long incubation periods in sheep and goats.Arthritis-Encephalitis Virus, Caprine: A species of LENTIVIRUS, subgenus ovine-caprine lentiviruses (LENTIVIRUSES, OVINE-CAPRINE), closely related to VISNA-MAEDI VIRUS and causing acute encephalomyelitis; chronic arthritis; PNEUMONIA; MASTITIS; and GLOMERULONEPHRITIS in goats. It is transmitted mainly in the colostrum and milk.Infectious Anemia Virus, Equine: A species of LENTIVIRUS, subgenus equine lentiviruses (LENTIVIRUSES, EQUINE), causing acute and chronic infection in horses. It is transmitted mechanically by biting flies, mosquitoes, and midges, and iatrogenically through unsterilized equipment. Chronic infection often consists of acute episodes with remissions.Equine Infectious Anemia: Viral disease of horses caused by the equine infectious anemia virus (EIAV; INFECTIOUS ANEMIA VIRUS, EQUINE). It is characterized by intermittent fever, weakness, and anemia. Chronic infection consists of acute episodes with remissions.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Goats: Any of numerous agile, hollow-horned RUMINANTS of the genus Capra, in the family Bovidae, closely related to the SHEEP.Simian immunodeficiency virus: Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). The genetic organization of SIV is virtually identical to HIV.Simian Acquired Immunodeficiency Syndrome: Acquired defect of cellular immunity that occurs naturally in macaques infected with SRV serotypes, experimentally in monkeys inoculated with SRV or MASON-PFIZER MONKEY VIRUS; (MPMV), or in monkeys infected with SIMIAN IMMUNODEFICIENCY VIRUS.Horses: Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.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.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Virus Replication: The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.Lentiviruses, Primate: A subgenus of LENTIVIRUS comprising viruses that produce immunodeficiencies in primates, including humans.Lentiviruses, Bovine: A subgenus of LENTIVIRUS comprising viruses that produce multi-organ disease with long incubation periods in cattle.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Transduction, Genetic: The transfer of bacterial DNA by phages from an infected bacterium to another bacterium. This also refers to the transfer of genes into eukaryotic cells by viruses. This naturally occurring process is routinely employed as a GENE TRANSFER TECHNIQUE.Puma: A genus in the family FELIDAE comprising one species, Puma concolor. It is a large, long-tailed, feline of uniform color. The names puma, cougar, and mountain lion are used interchangeably for this species. There are more than 20 subspecies.Cercopithecus: A genus of Old World monkeys found in Africa although some species have been introduced into the West Indies. This genus is composed of at least twenty species: C. AETHIOPS, C. ascanius, C. campbelli, C. cephus, C. denti, C. diana, C. dryas, C. erythrogaster, C. erythrotis, C. hamlyni, C. lhoesti, C. mitis, C. mona, C. neglectus, C. nictitans, C. petaurista, C. pogonias, C. preussi, C. salongo, and C. wolfi.Lions: Large, chiefly nocturnal mammals of the cat family FELIDAE, species Panthera leo. They are found in Africa and southern Asia.Lentiviruses, Feline: A subgenus of LENTIVIRUS comprising viruses that produce multi-organ disease with long incubation periods in cats.Sheep Diseases: Diseases of domestic and mountain sheep of the genus Ovis.Goat Diseases: Diseases of the domestic or wild goat of the genus Capra.Lemur: A genus of the family Lemuridae consisting of five species: L. catta (ring-tailed lemur), L. fulvus, L. macaco (acoumba or black lemur), L. mongoz (mongoose lemur), and L. variegatus (white lemur). Most members of this genus occur in forested areas on Madagascar and the Comoro Islands.Immunodeficiency Virus, Bovine: The type species of LENTIVIRUS, subgenus bovine lentiviruses (LENTIVIRUSES, BOVINE), found in cattle and causing lymphadenopathy, LYMPHOCYTOSIS, central nervous system lesions, progressive weakness, and emaciation. It has immunological cross-reactivity with other lentiviruses including HIV.Gene Transfer Techniques: The introduction of functional (usually cloned) GENES into cells. A variety of techniques and naturally occurring processes are used for the gene transfer such as cell hybridization, LIPOSOMES or microcell-mediated gene transfer, ELECTROPORATION, chromosome-mediated gene transfer, TRANSFECTION, and GENETIC TRANSDUCTION. Gene transfer may result in genetically transformed cells and individual organisms.Genetic Therapy: Techniques and strategies which include the use of coding sequences and other conventional or radical means to transform or modify cells for the purpose of treating or reversing disease conditions.