Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
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.
Pathological, entomological, avian and meteorological investigation of a West Nile virus epidemic in a horse farm. Pathological, entomological and avian investigations were conducted during the summer of 2002, in a horse farm that had four cases of West Nile virus (WNV) infection in horses. All the four horses had encephalitis and WNV infection was confirmed by RT-PCR and in situ hybridization procedure. Forty-seven per cent of house sparrows that resided on the farm were tested positive for WNV infection. Mosquitoes (98%Culex pipiens) collected by trapping at the farm, during this period were positive for WNV. The meteorological data for year 2002 were compared to previous 16 years. The precipitation and ...
Limited interdecadal variation in mosquito (Diptera: Culicidae) and avian host competence for Western equine encephalomyelitis virus (Togaviridae: Alphavirus). Historically, western equine encephalomyelitis virus (WEEV) caused large equine and human epidemics in the Americas from Canada into Argentina. Despite recent enhanced surveillance for West Nile virus, there have been few reports of equine or human cases and little documented enzootic activity of WEEV. During the past three years, WEEV has been active again in California, but without human or equine cases. In the current study, we compared host and vector competence of representative WEEV isolates made during each decade over the past 60 years using white-crowned sparrows, house sparrows, and ...
Chemoprophylactic effects of azithromycin against Rhodococcus equi-induced pneumonia among foals at equine breeding farms with endemic infections. To determine the effect of azithromycin chemoprophylaxis on the cumulative incidence of pneumonia caused by Rhodococcus equi, age at onset of pneumonia, and minimum inhibitory concentration (MIC) of azithromycin for R equi isolates cultured from fecal and clinical samples. Methods: Controlled, randomized clinical trial. Methods: 338 foals born and raised at 10 equine breeding farms; each farm had a history of endemic R equi infections. Methods: Group 1 foals were control foals, and group 2 foals were treated with azithromycin (10 mg/kg [4.5 mg/lb], PO, q 48 h) during the first 2 weeks after bi...
[Effect of the strategic control of Amblyomma cajennense (Fabricius, 1787) (Acari: Ixodidae) on the population of Anocentor nitens (Neumann, 1897) (Acari: Ixodidae) in equines]. The objective of this study was to evaluate the effect of the Amblyomma cajennense strategic control program on the Anocentor nitens population. The acaricide treatments were carried out every seven days and divided in two series, the first one beginning in April 2004 (eight treatments) and the second beginning in July of the same year (five treatments), using pyrethroid chemical base - cypermethrin in the concentration of 0,015%. Monthly it was evaluated the infestation of A. nitens in the ear and nasal diverticulum of the equines before (October 2003 to March 2004) and after (October of 2004...
Characterization of immunogenic proteins of Trypanosoma evansi isolated from three different Indian hosts using hyperimmune sera and immune sera. The western blot analysis for identification of immunogenic proteins in whole cell lysate (WCL) antigens (Ags) prepared from the Trypanosoma evansi of buffalo, horse and cattle origins using hyperimmune sera (HIS) showed 11 immunogenic proteins and naturally T. evansi infected immune sera (IS) of horse detected 19 immunogenic proteins. HIS and IS of horse recognized five common immunogenic proteins of relative molecular weight (M(r)) ranges 61-64, 44-47, 33-34, 25-26 and 14-16 kilo Dalton (kDa). HIS rose against WCL Ags of T. evansi of buffalo origin and immune sera of horse cross reacted with...
Transmission dynamics and changing epidemiology of West Nile virus. West Nile virus (WNV) is a flavivirus that is maintained in a bird-mosquito transmission cycle. Humans, horses and other non-avian vertebrates are usually incidental hosts, but evidence is accumulating that this might not always be the case. Historically, WNV has been associated with asymptomatic infections and sporadic disease outbreaks in humans and horses in Africa, Europe, Asia and Australia. However, since 1994, the virus has caused frequent outbreaks of severe neuroinvasive disease in humans and horses in Europe and the Mediterranean Basin. In 1999, WNV underwent a dramatic expansion of ...
Clinical, serological and molecular investigations of EHV-1 and EHV-4 in 15 unweaned thoroughbred foals. Fifteen unweaned thoroughbred foals, born on a stud farm to vaccinated mares, were clinically monitored during their first six months of life and repeatedly tested for equine herpesvirus type 1 (EHV-1) and equine herpesvirus type 4 (EHV-4). Nasopharyngeal swabs and blood samples were collected and screened respectively by PCR and seroneutralisation to detect the presence of the virus, explore its role as a possible cause of respiratory disease, and to assess the efficiency of the pcr for the diagnosis of this disease. The foals were divided into three groups on the basis of their clinical sign...
Multinodular pulmonary fibrosis in five horses. 5 horses were evaluated because of decreased appetite, weight loss, fever, cough, tachypnea, and respiratory distress. Results: Tachycardia, tachypnea, increased respiratory effort, lethargy, fever, poor body condition, and nasal discharge were detected in various combinations on initial physical examination. Evaluation of the lower portion of the respiratory tract via radiography and ultrasonography revealed a severe nodular interstitial pattern. Histologic examination of lung tissue revealed interstitial expansion of alveolar parenchyma with collagen, intraluminal accumulation of neutrophils...
Naturally arising point mutations in non-essential domains of equine infectious anemia virus Rev alter Rev-dependent nuclear-export activity. Equine infectious anemia virus (EIAV) exhibits a high rate of genetic variation in vivo, and results in a clinically variable disease in infected horses. In vivo populations of EIAV have been characterized by the presence of distinct, genetic subpopulations of Rev that differ in phenotype and fluctuate in dominance in a manner coincident with each clinical stage of disease. This study examined the specific mutations that arose in vivo and altered the phenotype. The Rev protein was found to be highly conserved, and only 10 aa mutations were observed at a frequency greater than 10 % in the sampl...
Health management of horses under high challenge from trypanosomes: a case study from Serengeti, Tanzania. Horses kept for recreational riding purposes by a wildlife tourism company in a heavily tsetse fly-infested region of north-western Tanzania were systematically monitored to investigate the occurrence, presentation and management of tsetse-transmitted trypanosomosis. During a 23-month period, 18 clinical cases were diagnosed (Trypanosoma brucei or Trypanosoma congolense were identified) and treated and trypanosomes were implicated of involvement in four deaths. Pyrexia consistently aided early detection (17 cases). Ataxia, weight loss and anaemia were seen in chronic cases and conferred a poor...
American cutaneous leishmaniasis in horses from endemic areas in the north-central mesoregion of Paraná state, Brazil. American cutaneous leishmaniasis (ACL) is an endemic disease in the north-west of Paraná state, Brazil, where it occurs in humans and dogs. Few studies have been undertaken on the occurrence of the disease in other domestic animals and horses. In this study we investigated the infection of horses by Leishmania in ACL-endemic rural areas. Direct agglutination test (DAT) and polymerase chain reaction (PCR) were employed. Fifty-five horses from rural areas in the municipalities of Doutor Camargo, Ourizona, São Jorge do Ivaí, Ivatuba and Santa Fé (Agua do O) were analysed. DAT-detected antibod...
Study of equid herpesviruses 2 and 5 in Iceland with a type-specific polymerase chain reaction. The horse population in Iceland is a special breed, isolated from other horses for at least 1000 years. This provides an exceptional opportunity to investigate old and new pathogens in an inbred herd with few infectious diseases. We have developed a high sensitivity semi-nested PCR to study equid gammaherpesviruses 2 and 5 (EHV-2 and 5) in Iceland. The first PCR is group specific, the second type-specific, targeting a 113bp sequence in the glyB gene. DNA isolated from white blood cells and 18 different organs was tested for the presence of EHV-2 and 5. This was done in adult horses and foals, ...
Detection of Bartonella henselae in the blood of 2 adult horses. Bartonella spp. are emerging zoonotic agents that have been found in a wide variety of domestic animals and wildlife and cause a number of clinical syndromes. Bartonella sp. infection has been identified in a growing number of animal species, including cats, rodents, porpoises, and canids, but has not been reported in horses. Objective: To document the presence of Bartonella sp. in the blood of horses. Methods: One horse with chronic arthropathy and 1 horse with presumptive vasculitis. Methods: Blood samples were tested for the presence of Bartonella sp. by a combination of multiplex real-time...
The pathology of bronchointerstitial pneumonia in young foals associated with the first outbreak of equine influenza in Australia. The first outbreak of equine influenza virus (EIV) infection was confirmed in Australia in 2007. Some EIV-positive young foals died with bronchointerstitial pneumonia, an rare disease process in this age group that is often postulated to be caused by viral infection. Objective: The aim of this study was to describe post mortem lesions in EIV-infected foals. Methods: Post mortem examinations were conducted on 11 young foals (age 2-12 days) submitted to the Scone Veterinary Hospital, NSW over a 2-month period in 2007. The foals had presented with or developed fatal pneumonia, and were known or s...
[Design of equine serum-based Marburg virus immunoglobulin]. Immunoglobulin (Ig) against Marburg fever (MF) has been obtained from the equine serum. In terms of physicochemical and immunobiological properties, the obtained preparation corresponds to the quality of heterologous commercial immunoglobulins. The application of Marburg virus (MV) Ig with a titer of no less than 1:2048 by the emergency prevention scheme 1-2 hours after intraperitoneal inoculation of guinea pigs with MV in a dose of 20-50 LD50 protected 88-100% of the animals from death. MV Ig is recommended for emergency prevention of human MF.
Comparison of two real-time reverse transcription polymerase chain reaction assays for the detection of Equine arteritis virus nucleic acid in equine semen and tissue culture fluid. Two previously developed TaqMan fluorogenic probe-based 1-tube real-time reverse transcription polymerase chain reaction (real-time RT-PCR) assays (T1 and T2) were compared and validated for the detection of Equine arteritis virus (EAV) nucleic acid in equine semen and tissue culture fluid (TCF). The specificity and sensitivity of these 2 molecular-based assays were compared to traditional virus isolation (VI) in cell culture. The T1 real-time RT-PCR had a higher sensitivity (93.4%) than the T2 real-time RT-PCR (42.6%) for detection of EAV RNA in semen. However, the T1 real-time RT-PCR was les...
Evaluation of antigen detection kits for diagnosis of equine influenza. In this study, we evaluated whether five rapid antigen detection kits for human influenza could be used for the diagnosis of equine influenza (EI). Limiting dilution analyses showed that Directigen Flu A+B and ESPLINE INFLUENZA A&B-N had the highest sensitivities to equine-2 influenza viruses (EIVs) among the kits investigated. From the results of virus detection in nasal swabs taken from horses infected with EIV, these two kits could produce positive results in reasonable agreement with those obtained by virus isolation or RT-PCR, suggesting that these kits could be useful for rapid diagn...
Antibody index and specific antibody quotient in horses after intragastric administration of Sarcocystis neurona sporocysts. To investigate the use of a specific antibody index (AI) that relates Sarcocystis neurona-specific IgG quotient (Q(SN)) to total IgG quotient (Q(IgG)) for the detection of the anti-S neurona antibody fraction of CNS origin in CSF samples obtained from horses after intragastric administration of S neurona sporocysts. Methods: 18 adult horses. Methods: 14 horses underwent intragastric inoculation (day 0) with S neurona sporocysts, and 4 horses remained unchallenged; blood and CSF samples were collected on days - 1 and 84. For purposes of another study, some challenged horses received intermitten...
Comparison of two indirect techniques for local delivery of a high dose of an antimicrobial in the distal portion of forelimbs of horses. To compare isolated limb retrograde venous injection (ILRVI) and isolated limb infusion (ILI) for delivery of amikacin to the synovial fluid of the distal interphalangeal and metacarpophalangeal joints and to evaluate the efficacy of use of an Esmarch tourniquet in standing horses. Methods: 6 healthy adult horses. Methods: Horses were randomly assigned in a crossover design. In ILRVI, the injection consisted of 1 g of amikacin diluted to a total volume of 60 mL administered during a 3-minute period. In ILI, the infusion consisted of 1 g of amikacin diluted to 40 mL administered during a 3-minu...
WITHDRAWN: Immunoprophylaxis against important virus diseases of horses, farm animals and birds. This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.
Identification of hyperendemic foci of horses with West Nile virus disease in Texas. To determine whether West Nile virus (WNV) disease hyperendemic foci (hot spots) exist within the horse population in Texas and, if detected, to identify the locations. Methods: Reports of 1,907 horses with WNV disease in Texas from 2002 to 2004. Methods: Case data with spatial information from WNV epidemics occurring in 2002 (1,377 horses), 2003 (396 horses), and 2004 (134 horses) were analyzed by use of the spatial scan statistic (Poisson model) and kriging of empirical Bayes smoothed county attack rates to determine locations of horses with WNV disease in which affected horses were consiste...
Association of soil concentrations of Rhodococcus equi and incidence of pneumonia attributable to Rhodococcus equi in foals on farms in central Kentucky. To determine whether soil concentrations of total or virulent Rhodococcus equi differed among breeding farms with and without foals with pneumonia caused by R equi. Methods: 37 farms in central Kentucky. Procedures-During January, March, and July 2006, the total concentration of R equi and concentration of virulent R equi were determined by use of quantitative bacteriologic culture and a colony immunoblot technique, respectively, in soil specimens obtained from farms. Differences in concentrations and proportion of virulent isolates within and among time points were compared among farms. Resul...
