Topic:Infectious Disease
Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Equine abortion (herpes) virus: strain differences in susceptibility to inactivation by dithiothreitol. The infectivity of equine abortion (herpes) virus (EAV) was inactivated by treatment with reduced dithiothreitol (DTT). According to their susceptibility to DTT, the EAV strains could be divided into three groups. The vaccine strain RAC-H (419) proved to be more resistant to DTT than all of the other 14 strains tested. The hemagglutinin of EAV was also inactivated by DTT; no strain differences were observed in this respect.
Study of the one-step growth curve of equine infectious anemia virus by immunofluorescence. Primary horse leukocyte cultures were inoculated with 2 or 10 50% tissue culture infective doses (TCID(50)) of equine infectious anemia (EIA) virus per cell, and the titer of cell-associated and fluid-phase virus was determined from 1 to 72 hr postinoculation (PI). Cover slips were collected from 4 to 72 hr PI and stained for EIA viral antigen by the indirect immunofluorescent (FA) technique. Viral replication was detected after a latent period of approximately 18 to 24 hr and reached peak titers of approximately 10(4.5) to 10(6) TCID(50)/0.5 ml from 48 to 72 hr PI. The fluid phase contained 1...
Experimental infection of horses with an attenuated Venezuelan equine encephalomyelitis vaccine (strain TC-83). Ten horses (Equus caballus) were vaccinated with strain TC-83 Venezuelan equine encephalomyelitis (VEE) virus vaccine. Febrile responses and leukopenia due to a reduction of lymphocytes and neutrophils were observed in all animals. Viremias were demonstrable in eight horses, with a maximum of 10(3.5) median tissue culture infectious dose units per ml of serum in two horses. Clinical illness with depression and anorexia were observed in five horses. Neutralizing (N), hemagglutination-inhibiting, and complement-fixing antibodies to the vaccine virus were demonstrable by 5, 6.5, and 7 days, respe...
Detection of African horsesickness viral antigens in tissues by immunofluorescence. The fluorescent antibody reaction was studied in tissues of ponies infected with African horsesickness virus (AHSV). Lung, spleen, lymph node, liver, skeletal muscle, intestine, stomach, nerve ganglion and kidney were sectioned and stained by the direct fluorescent antibody technique (FA). Fluorescence was demonstrated only in the spleen and could be inhibited by using unconjugated antiserum.
Equine infectious anemia: preparation of a liquid antigen extract for the agar-gel immunodiffusion and complement-fixation tests. An agar-gel immunodiffusion test recommended for the diagnosis of equine infectious anemia was evaluated. Our preliminary observations confirmed those of Coggins concerning the mechanism of the test and the results obtained. Furthermore, emphasis was put on the difficulties encountered in the production of spleen antigens with an optimum amount of reactivity. Acetone-ether extraction procedures for the preparation of a liquid antigen extract are described. This type of antigen was reactive in the complement-fixation test in 1:8 or greater dilution and it is proposed to use the complement-fixat...
Detection of chlamydial antibodies in animal sera by double diffusion in gel. Postinoculation sera collected from pigeons, turkeys, guinea pigs, sheep, a calf, a rabbit, and a horse experimentally infected with various strains of Chlamydia psittaci yielded a high incidence of positive reactions when tested by double diffusion in gel. Antigen was a deoxycholate extract of SA-2 strain of C. trachomatis. Good correlation was obtained with results of complement fixation tests, whereas double diffusion in gel was less sensitive. Immunoelectrophoresis of the antigen revealed presence of two antigens in the extract.
Stability of live attenuated Venezuelan equine encephalitis vaccine. Reconstituted Venezulean equine encephalitis vaccine was found to retain significant titers of plaque-forming virus after storage at 4 or 22 C for 24 hr.
Brucellosis in the horse. Brucella abortus infection in horses is important not only as a clinical entity but also as a potential source of infection for man and other animals. A review of the current knowledge of this disease in the horses is therefore thought to be useful. The incidence of infection in horses has been the subject of many surveys. Most authors used the serum agglutination test as an indication of infection. The majority of surveys were carried out in about 1930 and these showed a wide range in the proportion of positive reactors from 0.5 to 40 percent. Several factors would account for this: variation...