Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Epidemiology
Epidemiology in horses involves the study of the distribution and determinants of health-related states and events in equine populations. It encompasses the investigation of patterns, causes, and effects of diseases and health conditions within horse populations. This field of study aims to identify risk factors for disease and targets for preventive healthcare. Key components of equine epidemiology include disease surveillance, outbreak investigation, and the study of disease dynamics within herds or regions. Research in this area often focuses on infectious diseases, zoonotic diseases, and the impact of environmental factors on equine health. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of epidemiology in horses, including disease prevalence, transmission pathways, and strategies for disease prevention and control.
Isolation and identification of African horse sickness virus during an outbreak in Lagos, Nigeria. An outbreak of African horse sickness involving two horse stables in Lagos, Nigeria, was investigated. Inoculation of blood from infected horses into suckling albino mice resulted in isolation of a virus which was identified as African horse sickness virus by the complement fixation test. The clinical, pathological and epizootiological findings (reported elsewhere) were consistent with African horse sickness. Potential threats of the epidemic to international horse trade are briefly highlighted.
The isolation and identification of Potchefstroom virus: a new member of the equine encephalosis group of orbiviruses. Virus was isolated from the blood of horses (n = 5) showing fever and jaundice and was identified as equine encephalosis virus. In cross neutralisation tests, the isolates were shown to belong to a new serotype related to Gamil, one of the 6 known serotypes of equine encephalosis virus. The name Potchefstroom has been proposed for this new serotype.
Radiographic evaluation of ossification of the collateral cartilages of the third phalanx in Finnhorses. Of 462 Finnhorses (age 1-20 years) evaluated and graded (scale 0-5) radiographically for ossification of the collateral cartilages of the 3rd phalanx of the front feet, 22.9% were totally free from sidebones (Grade 0), and 49.1% had minimal or mild ossification (Grade 1 or 2) at the base of 1 or more of the cartilages. Moderate ossification (Grade 3) was present in 10.2% of the horses, whereas ossification was advanced (Grade 4) or extensive (Grade 5) in 17.8%. In most horses > 1 cartilage was affected and 7.6% of the horses had separate centres of ossification in 1 or more of the cartilages. ...
Diagnosis and prediction of cervical vertebral malformation in thoroughbred foals based on semi-quantitative radiographic indicators. Over a period of 5 years on a central Kentucky Thoroughbred stud farm 132 foals were evaluated for the presence of cervical vertebral malformation (CVM). Lateral cervical vertebral radiographs were obtained on 70 standing foals. These radiographs were evaluated semi-quantitatively and scored numerically for the presence of stenosis of the vertebral canal, enlarged physeal growth plates, caudal extension of the dorsal border of the orifice of the vertebral canal, angular fixation, delayed ossification of bone and degenerative joint disease. From these scores a total CVM score was given for each...
Plasma endotoxin concentrations in clinically normal and potentially septic equine neonates. Plasma endotoxin concentrations were measured at 1 to 2 and 5 to 6 days of age in clinically normal foals and in potentially septic neonatal foals admitted to North Carolina State University's Veterinary Teaching Hospital for a variety of conditions. In 1 to 2 and 5 to 6 day old normal foals, median plasma endotoxin concentrations were 2.17 (range, 1.61-2.54; n = 6) and 2.89 (range, 2.61-3.50; n = 7) endotoxin units/mL (EU/mL), respectively. Median plasma endotoxin concentration in potentially septic foals with negative blood cultures or gram positive isolates (n = 8) was 2.73 (range, 0.59-4.0...
Immunoglobulin (IgG and IgA) and complement (C3) concentrations in uterine secretion following an intrauterine challenge of Streptococcus zooepidemicus in mares susceptible to versus resistant to chronic uterine infection. The validity of measuring concentrations of immunoglobulins in undiluted uterine secretions was established. The concentrations of IgG, IgA, and cleavage factor C3 of the complement system in uterine secretions were compared in mares with different resistance to chronic uterine infection (CUI). The uteri of mares susceptible (n = 6) and resistant to CUI (n = 5) were inoculated with 5 x 10(6) Streptococcus zooepidemicus when the mares were in estrus. Uterine secretions were sampled, and sampling was immediately followed by a uterine lavage at 5 and 24 h after bacterial inoculation. During a sub...
Injuries due to falls from horses. This study describes the epidemiology of injuries due to falls from horses in New Zealand. There were 54 fatalities from 1977 to 1986 (0.17 per 100,000 persons per year). There were 773 hospitalisations in 1987 (23.7 per 100,000 persons per year). Head injuries were predominant among both fatal and nonfatal injuries. The incidence of nonfatal head injury in the 10 to 19 age group was significantly higher than the incidence in all older groups (P = 0.003). Young people, particularly females, were the segment of the population most affected by the problem of falls from horses. Reference to data ...
Rhodococcus equi. This article summarizes recent advances in understanding of the epidemiology, pathogenesis, clinical and laboratory diagnosis, immunology, treatment, and control of Rhodococcus equi infections in foals. Our understanding of these aspects currently is sufficient to ensure control of this problem on affected farms and in infected foals. More information, however, is needed on factors predisposing foals to R. equi pneumonia, in particular, the nature of the naturally occurring cellular immunodeficiency in foals of 2 to 4 months of age, which also predisposes them to severe respiratory infection w...
Clostridia-associated enterocolitis in adult horses and foals. A review of the literature describing clostridia-associated enterocolitis is presented. The bacteria, their toxins, and possible factors that interact to contribute to the pathogenesis of enterocolitis are described. Clinical signs associated with clostridia-associated enterocolitis, methods of diagnosis, treatments, and preventive strategies are discussed.
Application of epidemiologic principles and methods to investigating and controlling equine infectious diseases. Epidemiology is a tool much like any other diagnostic tool that the practitioner uses as an aid in the complete physical examination of the group of animals. It can be used to generate a specific differential diagnosis list. Epidemiology is especially useful to design a disease control and prevention program by helping to elucidate the key determinants of disease occurrence.
[Pilot study of the occurrence of Prototheca in fecal samples of horses]. Fecal samples of 146 horses were culturally investigated for occurrence of Prototheca spp. using a selective medium, developed by PORE (1973). Prototheca zopfii could be isolated in monoculture from 9 fecal samples (6.2%). The results of this pilot study show that horses too can harbour and shed Prototheca spp. in variable frequency.
[Salmonellosis in the horse]. Salmonellosis is a worldwide problem of both men and animals. Equine salmonellosis is an increasing problem and a review of the recent knowledge is given. Etiology, symptomatology, diagnostic procedures, therapy and prevention are discussed.
A minor prevalent strain in a severe outbreak of foal diarrhea associated with serotype 3 rotavirus. An epizootic of foal diarrhea due to serotype 3 rotavirus (RV) was observed in 89 of 168 cases (53%) during the period from March to July in 1987. A total of 51 strains of RV were isolated from the 62 diarrheal feces examined, and one isolate (CH-3) showed a unique electropherotype of viral RNA which differed from the others that widely prevailed on this farm. No positive reaction was observed between strain CH-3 and each of the antisera against serotypes 1 to 12 of human and animal RV in neutralization tests. However, dsRNAs of the CH-3 virus were hybridized with a probe prepared from a strai...
African horse sickness. AHS is a noncontagious vector-borne disease of Equidae caused by Orbiviruses. Species susceptibility in decreasing order is horses, mules, donkeys, and zebras. The main vectors of AHS are culicoides. The disease is endemic in sub-Saharan Africa, but epizootics have occurred outside of this area on several occasions. The most recent outbreaks outside of the endemic area were in Spain, Morocco, and Portugal between 1987 and 1990. AHS causes mortality up to 95% and is classically divided into four clinical forms: the pulmonary, cardiac, mixed, and horse fever forms. Pathologic changes are subcuta...
Equine rabies. With the continued increase in the number of wildlife rabies cases reported across the United States and Canada, this disease will remain a threat to the horse as the potential for exposure to infected wildlife and other domestic animals is likely to also increase. Because there are no rapid, definitive antemortem diagnostic tests, the tentative diagnosis is based upon the variable and sometimes nonspecific clinical signs. Although the CSF analysis may be helpful in some cases, it may not be abnormal. Nor is collection of the specimen always practical in the field situation. The FAT on neural ...
Rhodococcus equi-associated osteomyelitis in foals. Two cases of Rhodococcus equi infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equi until proven otherwise.
Rotaviral diarrhea. Rotavirus poses a challenge each foaling season to farm managers and veterinarians in intensive horse breeding areas throughout the world. By understanding the epidemiology of the disease as well as characteristics of the virus, veterinarians can make sound recommendations on prevention and control of outbreaks. Even when effective prophylactic products are developed, farm management practices, including quarantine, disinfection, and hygiene, will always need to be in force to prevent any contagious disease outbreak.
Equine influenza. Influenza continues to be one of the most important diseases of horses despite the availability and widespread use of equine influenza vaccines for almost 30 years. In recent years, infection with the influenza A/equine/2 subtype has become endemic in the equine populations of North America, Europe, and Scandinavia. Continued antigenic drift of field virus has compromised the efficacy of vaccines, most of which contain antigens prepared from influenza viruses isolated more than 10 years ago. This article reviews the history, virology, epidemiology, pathogenesis, immunology, clinical presentati...
[Reproduction data in breeding mares, diseases and losses among suckling foals and preventive husbandry in German stud farms]. By means of a survey, the reproductive rate of mares and the foal losses in ten Thoroughbred, Saddlebred and Pony studs in Germany, mainly from North-Rhine-Westfalia, were collected and evaluated. Data for the survey were recorded for 1985-1990. The study also examined the hygienic management in the surveyed studs, and the morbidity rate of suckling foals was obtained for 1990. In addition to the survey questionnaire each stud was visited once. Two studs of each horse group were visited several times every week from March to August in order to evaluate as exactly as possible the husbandry and ...
African horse sickness. AHS is a noncontagious vector-borne disease of Equidae caused by Orbiviruses. Species susceptibility in decreasing order is horses, mules, donkeys, and zebras. The main vectors of AHS are culicoides. The disease is endemic in sub-Saharan Africa, but epizootics have occurred outside of this area on several occasions. The most recent outbreaks outside of the endemic area were in Spain, Morocco, and Portugal between 1987 and 1990. AHS causes mortality up to 95% and is classically divided into four clinical forms: the pulmonary, cardiac, mixed, and horse fever forms. Pathologic changes are subcuta...
African horse sickness. AHS is a noncontagious vector-borne disease of Equidae caused by Orbiviruses. Species susceptibility in decreasing order is horses, mules, donkeys, and zebras. The main vectors of AHS are culicoides. The disease is endemic in sub-Saharan Africa, but epizootics have occurred outside of this area on several occasions. The most recent outbreaks outside of the endemic area were in Spain, Morocco, and Portugal between 1987 and 1990. AHS causes mortality up to 95% and is classically divided into four clinical forms: the pulmonary, cardiac, mixed, and horse fever forms. Pathologic changes are subcuta...
Characterization of virulence variants of African horsesickness virus. There are three clinicopathologic syndromes associated with African horsesickness (AHS) virus infection in horses. These different forms of AHS (pulmonary, cardiac, and fever forms) vary in the organs affected, the severity of lesions, time of onset of clinical signs and mortality rates. We have studied the effects of infection with three cell culture passaged variants of AHS virus in naive North American horses. One of these viruses, AHS/4SP, consistently caused the pulmonary form of AHS with rapid onset of severe pulmonary edema and 100% mortality. A second variant, AHS/9PI, resulted in sign...
The equine herpesviruses. Two viruses, EHV-1 and EHV-4, are now known to be responsible for disease conditions formerly considered caused by "equine rhinopneumonitis virus." Although these viruses share several laboratory and clinical features, they differ in epidemiology and pathogenic potential. EHV-4 is primarily associated with clinical respiratory disease, whereas EHV-1 is more frequently isolated from aborted fetuses, sickly foals, and neurologic cases. Both viruses frequently establish latent infections, but the relevance of latency to clinical disease is unclear. Diagnosis based on identification of the pathoge...
Diversity within natural populations of eastern equine encephalomyelitis virus. We evaluated genetic and phenotypic diversity within natural populations of the alphavirus, Eastern equine encephalomyelitis (EEE) virus. RNA fingerprinting revealed that most populations within infected hosts (unpassaged isolates) contained a consensus genotype along with minority genotypes differing in one to three T1-resistant oligonucleotides. Mutation frequencies appeared to be similar to those reported for other RNA viruses, suggesting that the slow rate of EEE virus evolution is not limited by fidelity of genome replication. Within a given year, genetic diversity was generally greater a...
Salmonellosis. Salmonellosis is the most common infectious cause of diarrhea or colitis in horses. It can be associated with high fatality rates in patients with compromised host defenses. The increasing incidence of infection and antimicrobial resistance present a challenge for the practicing veterinarians. The epidemiology and pathogenesis of salmonellosis are reviewed. Diagnosis, treatment, and control of disease are discussed.
Comparison of five tests for the serologic diagnosis of myiasis by Gasterophilus spp. larvae (Diptera: Gasterophilidae) in horses and donkeys: a preliminary study. Sera from 41 horses and 159 donkeys, from twelve States of México, were tested to ascertain anti-Gasterophilus circulating antibodies by double immunodiffusion (DD), counterimmunoelectrophoresis (CIE), indirect haemagglutination (IH), thin layer immunoassay (TIA) and diffusion-in-gel ELISA (DIG-ELISA) methods using crude somatic antigen from third instar larvae of G. intestinalis (DeGeer). At necropsy, 33/41 horses and 24/159 donkeys were found to be parasitized by G. intestinalis and/or G. nasalis (L.). Gasterophilus intestinalis was the species most commonly found in the equines. Analysis o...
Heritability estimations of osteochondrosis in the tibiotarsal joint and of bony fragments in the palmar/plantar portion of the metacarpo- and metatarsophalangeal joints of horses. Radiography of the tibiotarsal and metacarpo- and metatarsophalangeal joints was performed on 753 Standardbred trotters (6 to 21 months old) born in 1988. The surveyed population was drawn at random from all parts of Norway and represented about 60% of Standardbred trotters born the same year. Osteochondrosis in the tibiotarsal joint was diagnosed in 108 (14.3%) horses, and the prevalence of disease in progeny groups > 10 ranged from 0 to 69%. Bony fragments in the palmar/plantar portion of the metacarpo- and metatarsophalangeal joints were diagnosed in 89 (11.8%) horses, and the prevalence of...
