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.
Antal V, Antal T, Szabó I, Vajda G, Polner A, Szollár I, Totth B, Laber G, Stipkovits L.The authors examined 585 samples from 92 mares of 2 studs and 346 nasal swabs taken from their foals for the presence of mycoplasmas. The positive rates of mares and foals were 81.5% and 71.7%, respectively, with positivity of samples being variable. Clinical symptoms developed in 2-4 waves and lasted 3-7 days, with intervals of 7-12 days. The disease started in April among foals born in February, at an average age of 88 days. Later on, the average age of the affected foals decreased. There was a correlation between presence of mycoplasmas in nasal cavity and disease of foals.
Hendrikx WM, Jansen J, de Vries TJ.An infection with second-stage larvae of the warble-fly H. diana in a horse is described. The second-stage larvae were incapable of developing into the third stage, because horses are unsuitable hosts and because the infected horse was treated with an insecticide. Since the horse was used for dragging trees in the forests, the infection was likely contracted via contact with H. diana, a normal parasite of roe deer in the Netherlands.
Andersson-Eklund L, Andersson L, Sandberg K.A study was carried out to attempt to explain the basis of the association between the Es locus and starting proportion in Swedish Trotters which had been observed previously. The effect of Es genotype on starting proportion has diminished among horses born in the late 1970s. There are indications that the incidence of leg lesions varies between Es genotypes. If this is true, it is possible that the decreasing effect of the Es locus on starting proportion is due to the environmental changes which have been made at race tracks in the early 1980s to reduce the strain on the legs of the trotters....
Matsushita T, Hesterberg LK, Porter JP, Smith BJ, Newman LE.Two diagnostic tests are approved for detecting antibody to equine infectious anemia virus: the agar-gel immunodiffusion (AGID) test and the competitive enzyme-linked immunosorbent assay (ELISA). A total of 420 sera from National Veterinary Services Laboratories check sets were tested with the AGID and competitive ELISA. A 100% correlation was obtained. The AGID and competitive ELISA were further used to test difficult samples with low levels of equine infectious anemia antibody (weak positives). A third test (Western blot) was also used with these weak positive samples to resolve any discorda...
Browning GF, Studdert MJ.The BamHI, EcoRI, and HindIII physical maps of the genomes of 14 isolates of equine herpesvirus 2 (EHV 2) were determined by Southern blot analysis using DNA fragments of a previously mapped EHV 2 strain 86/67. No two isolates had identical maps for all 3 enzymes, the number of differing cleavage sites between pairs of isolates varying from 3 to 21. Overall 75 cleavage sites were mapped, of which 40 were variable. Cleavage sites occurred throughout the genome, including within the terminal repeat regions. Additionally, fragment length polymorphisms, independent of cleavage site loss or gain, w...
Harasawa R, Higashi T.Viral DNA obtained from the equine adenovirus propagated in equine transitional cell carcinoma (ETCC) cells and in equine fetal dermis cells were compared by cleaving with isoschizomeric restriction enzymes, HpaII and MspI, and then electrophoresed in 1.4 per cent agarose gels. Differences between the HpaII and MspI cleavage patterns were evident in viral DNA obtained only from the equine adenovirus propagated in ETCC cells, suggesting site specific methylation at CpG sequences.
The Journal of traumaJanuary 1, 1989
Volume 29, Issue 1 25-30 doi: 10.1097/00005373-198901000-00005
Ingemarson H, Grevsten S, Thorén L.Riding accidents can be of a serious nature. Knowledge of risk factors is of essential value in the prevention of injuries. From the years 1969 through 1982 a series of 53 lethal riding injuries is analysed with reference to the rider, the horse, and the environment. Craniocerebral injuries dominate in this series, indicating the importance of adequately protecting helmets. Among the victims the female sex is dominating before the age of 25 and the males above this age. Older horses are less frequently involved in these accidents than younger ones. A long training period for riders under surve...
Gerber H, Ueltschi G, Diehl M, Schatzmann U, Straub R.For various anamnestic reasons the cervical vertebral column of 78 horses was examined radiologically. Statistical comparisons showed that male "warmbloods" were more frequently affected than was expected. Our horses were older than comparable animals in the international literature. Independently of their history the radiologic diagnosis of "cervical spondylarthrosis" was established in 56 horses. Arthrosis and other conditions were clinically manifested by spinal ataxia (44 horses) or mechanical impairment of the neck's mobility (21 horses). 10 of the arthrotic patients had synovial cysts ca...
Valpotić I, Kastelan M, Rudolf M, Gerencer M, Jukić B, Basić I.The percentage of T and B lymphocytes in the peripheral blood of horses chronically infected with equine infectious anaemia (EIA) virus was determined and the results were compared with the percentage of these cells in healthy uninfected horses. Cells with membrane receptors for sheep erythrocytes (T and active T lymphocytes) were determined by E and A rosette techniques, while cells with receptors for the C3b component of complement and those with receptors for mouse erythrocytes (B lymphocytes), were determined by the EAC rosette method. The percentage of Fe positive cells was assayed by the...
Park CA, Hines HC, Threlfall WR.Equine lymphocyte antigen (ELA) gene frequencies were estimated for pacing and trotting Standardbred mares residing on a breeding farm in central Ohio. The ELA gene frequencies for Ohio Standardbreds did not differ significantly from the ELA gene frequencies of Kentucky Standardbreds, determined by Bailey (1983). No significant differences were found in the distribution of ELA class I antigens in horses with lower overall fertility or a history of abortion on the investigated breeding farm. Likewise, no significant association was observed when the ELA types of both the mare and the stallion t...
Mfitilodze MW, Hutchinson GW.A quantitative post-mortem study of 57 horses from northern Queensland was done to determine the prevalence and intensity of non-strongyle intestinal parasites. The following species (% prevalence) were found: Draschia megastoma (39%); Habronema muscae (43%); Gasterophilus intestinalis (34%), G. nasalis (30%); Parascaris equorum (15%); Strongyloides westeri (6%); Probstmayria vivipara (2%); Oxyuris equi (26%); Anoplocephala magna (2%); A. perfoliata (32%). Mean parasite numbers of individual species ranged from 10 to 1310. Prevalence and intensity data were compared to recent studies in Wester...
Soulé C, Boulard C, Levieux D, Barnouin J, Plateau E.Three, four, and one horses were respectively infected with 100, 1,000, and 5,000 metacercariae of Fasciola hepatica. Six of them were reinfected 38 weeks later with 1,000 metacercariae each. Specific antibodies assayed by counter-electrophoresis, passive hemagglutination and ELISA tests appeared three to six weeks post-infection and peaked 10 to 17 weeks post-infection. Horses infected by 1,000 metacercariae and more showed 17.6% of positive samples by counter-electrophoresis, 49.2% by ELISA, and 75.6% by passive hemagglutination. Plasma glutamate dehydrogenase and gamma-glutamyltransferase l...
Shankarappa B, Dutta SK, Sanusi J, Mattingly BL.Competitive enzyme-linked immunosorbent assay (CELISA), mediated by a monoclonal antibody designated HybI, was developed for the diagnosis of equine monocytic ehrlichiosis. Inhibition of binding of HybI by the horse antibodies to Ehrlichia risticii was optimum at dilutions of 1:20 for serum and 1:10,000 for HybI. Mean optical densities (ODs) of positive and negative sera were 0.158 and 0.855, respectively. A comparison of ODs obtained by CELISA and indirect enzyme-linked immunosorbent assay (ELISA) indicated a marked tendency of positive and negative samples to cluster separately with respect ...
Kawaoka Y, Webster RG.A severe influenza outbreak occurred in horses in South Africa in 1986. The causative agent was identified as an influenza virus [A/Equine/Johannesburg/86 (H3N8)]. Antigenic analyses of the hemagglutinin (HA) with ferret antisera and monoclonal antibodies showed that the Eq/Johannesburg/86 virus is similar to recent equine H3 viruses. The nucleotide sequence analysis on the HA genes of Eq/Johannesburg/86 and other equine H3 influenza viruses, together with the epidemiological data, clearly demonstrated that the Eq/Johannesburg/86 virus was derived from a virus that had been circulating in hors...
Jolly RD, Dalefield RR.The lipopigments are a heterogenous group of pigments whose pathogenesis and terminology is confused. Whereas there is epidemiological and observational evidence that ceroid is derived from degeneration and peroxidation of unsaturated lipid, the assumption that all so-called lipopigments are similarly formed, is questioned. In particular, recent studies have distanced the pathogenesis of the pigment found in the ceroid-lipofuscinoses from that perceived for ceroid. The importance of protein rather than lipid in the pathogenesis of the pigment of ceroid-lipofuscinosis and of age pigment from th...
Al-Izzi SA, Al-Bassam LS.Pseudomonas mallei was isolated from pus samples obtained from 34 mallein-positive horses. The isolates were subjected to in vitro sensitivity test using 16 different antimicrobial discs. All isolates (34) were sensitive to sulfamethizole, gentamycin, tetracycline, sulfathiazole, kanamycin, tobramycin, streptomycin and a combination of trimethoprim and sulfamethoxazole while none of them were sensitive to cephalothin, colistin, ampicillin, penicillin and nitrofurantoin. Rifapicin, chloramphenicol and carbenicillin were effective against 32, 26 and 18 isolates respectively. The minimum inhibito...
Sellers RF, Maarouf AR.Information was collected on confirmed outbreaks of western equine encephalitis (WEE) in North America east of the Rockies for 1981 and 1983 (epidemic years) and 1980 and 1982 (non-epidemic years). The initial pattern of outbreaks in Manitoba, Minnesota and North Dakota was determined for each year. Backward (and in some instances forward) wind trajectories were computed for each day 4-15 days (incubation period) before the initial outbreaks of WEE in a given area of province or state. During these years the timing and location of WEE outbreaks in horses and man, seroconversion in chickens, th...
Karabatsos N, Lewis AL, Calisher CH, Hunt AR, Roehrig JT.A virus, strain 64A-1519, isolated from the brain of a horse dying of encephalitis in Florida in 1964, was identified as western equine encephalomyelitis (WEE) virus. Recently, we used polyclonal and monoclonal immune reagents to identify this isolate by comparing it to 2 strains of WEE virus and to Highlands J (HJ) virus in hemagglutination-inhibition, immunofluorescent antibody, and plaque-reduction neutralization tests. These tests demonstrate that strain 64A-1519 is a strain of HJ virus distinct from WEE virus.
Ebisawa I, Takayanagi M, Kigawa M.Clostridium tetani was isolated from human and animal stools at the following rates [95% confidence interval (CI)]: Human, 0% (1.5-0); horse, 1% (5-0); cow in cowshed, 4% (10-1); cow in pasture, 8.3% (17-1), calf in pasture, 0% (7-0); dog, 2% (11-0) and sheep in pasture, 25% (44-14). Quantification of C. tetani in 16 animal stools positive for the bacillus was impossible in most cases, as the number of tetanus bacilli present was not large enough for this purpose. Contaminating anaerobic and facultative anaerobic bacteria in human and animal stools, i.e., C. perfringens and Streptococcus sp., ...
Owen RA, Jagger DW, Quan-Taylor R.The prevalence of Anoplocephala perfoliata in 103 horses and ponies from Clwyd, Powys and the adjacent English marches, slaughtered during January 1987, was 69 per cent.
Calisher CH, Oro JG, Lord RD, Sabattini MS, Karabatsos N.A virus isolated from the blood of a febrile horse in Argentina was identified as a strain of Kairi virus. This is the fifth Bunyamwera serogroup virus isolated from livestock and wild animals in the Americas. Bunyamwera serogroup viruses have been isolated from febrile humans in the Americas and Africa.
Bauer C.The prevalence of Eimeria leuckarti infection and the intensity of faecal oocyst output were determined in a herd of 14 mares and their foals in northwest Germany using a sedimentation technique at weekly intervals during a summer grazing season from May to September. None of the mares, but all foals shed oocysts on at least one occasion. The patent periods lasted up to 16 weeks. The mean intensity of oocyst output (0.1-33 o.p.g.) was very low. No clinical signs of gastrointestinal disorder were noticed in any of the foals during this study.
Braverman Y.Six hundred and twenty culicoides of five species were collected from a bait horse at Kannot, Israel, between April and September 1986. Seventy-two per cent of the midges were collected from the belly and 27 per cent from the dorsal aspect of the body, ie, the sweet itch summer seasonal recurrent dermatitis (SSRD) zone. Midges were active mainly from half an hour prior to half an hour after sunset. Only Culicoides puncticollis, C imicola and C schultzei group were collected in considerable numbers. While C imicola was present continuously throughout the season, the appearance of the two other ...
Hall RF, Pursell AR, Cole JR, Youmans BC.An epizootic of equine infectious anemia (EIA) involved 35 horses on a farm in south Georgia. During a 126-day period, 21 of these horses became seropositive for EIA. After the initial diagnosis in July, the horses were tested every 7 to 10 days. At least one additional horse was found to be seropositive on each testing day. As soon as they were determined to be seropositive, the horses were removed from the herd and sent to slaughter. The removal of the seropositive horses, however, did not stop the epizootic. We believe the initial infection was from a 7-year-old stallion that recently had b...
Prescott JF, Staempfli HR, Barker IK, Bettoni R, Delaney K.Severe colitis was induced in two ponies after oral pretreatment with clindamycin and lincomycin, followed by intestinal content from two horses which had died from naturally-occurring idiopathic colitis. Two ponies treated with antibiotic alone, and two ponies treated with intestinal content alone, were unaffected. In a further study, three ponies treated on separate occasions with lincomycin, administered orally, died or were destroyed 67 to 72 h after initial treatment. No established salmonella, yersinia or campylobacter pathogens were isolated from these ponies, but a clostridium closely ...
Duncan JL, Arundel JH, Drudge JH, Malczewski A, Slocombe JO.These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp, which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, do...
Ghanem YM, Ibrahim el-SM, Yamada S, Matsumura T, Osterrieder N, Yamaguchi T, Fukushi H.The pathogenicities of RacL11 and Kentucky D strains of equine herpesvirus 1 in the hamster infection model are different from those of Ab4p and the Japanese isolates. Virus genome restriction fragment length polymorphism analysis and sequence comparison of an intergenic region, glycoproteins and tegument genes showed higher conservation but with some strain-specific differences. These results indicate that point nucleotide differences in RacL11 and Kentucky D might be responsible for their pathogenicity in rodent models.
Slater MR, Hood DM, Carter GK.A descriptive and matched case-control study of laminitis was conducted in 7 private practices and at the Texas Veterinary Medical Centre (TVMC) between May 1992 and July 1993. Out of 108 horses with laminitis, 19 acute (49%) and 20 chronic (51%) cases were seen in private practice and 16 acute (23%) and 53 (77%) cases at the TVMC. Gastrointestinal disease was the most common problem in 19/35 horses (54%), occurring just prior to the onset of acute laminitis in all hospitals. Among all horses in the study, most commonly used drugs were phenylbutazone (68%), acepromazine (34%), dimethyl sulphox...
Dhaouadi S, Mahjoub T, Drissi G, Bahri A, Mhadhbi M, Sassi L, Gharbi M.Leishmaniosis (Leishmania infantum infection) and piroplasmoses (Theileria equi and Babesia caballi infections) are vector-borne diseases with significant economic and public health impacts. Despite their importance, there is a lack of data concerning these infections in equids from Tunisia. The present study was carried out to estimate the prevalence of L. infantum, T. equi and B. caballi in 104 equids from northern Tunisia. The authors reported for the first time on the seroprevalence of anti-Leishmania antibodies in equids in Tunisia (6.7%). The study reported a high infection prevalence of...
Naudé TW, Gerber R, Smith RJ, Botha CJ.Datura poisoning of horses is extensively reviewed. An outbreak of intractable impaction colic affecting 18 of 83 horses was stopped by withdrawing dried tef hay contaminated with young Datura plants. The dried, botanically identified Datura stramonium and D. ferox contained respectively 0.15% mass/mass (m/m) hyoscyamine as well as 0.16% m/m hyoscine (scopolamine) and only hyoscine at a concentration of 0.11% m/m. Immature, unidentifiable plants resembling D. stramonium, contained 0.14% m/m and 0.12% m/m of the 2 respective tropane alkaloids. The outbreak was characterised by protracted and re...
Ochi A, Bannai H, Aonuma H, Kanuka H, Uchida-Fujii E, Kinoshita Y, Ohta M, Kambayashi Y, Tsujimura K, Ueno T, Nemoto M.Mosquitoes and EDTA-treated blood samples from febrile racehorses were investigated for Getah virus infection from 2016 to 2019 at the Miho Training Center, where several outbreaks of Getah virus have occurred. We collected 5557 mosquitoes and 331 blood samples from febrile horses in this study. The most frequently captured mosquito species was Culex tritaeniorhynchus (51.9%), followed by Aedes vexans nipponii (14.2%) and Anopheles sinensis (11.2%). Getah virus was detected in mosquitoes (Aedes vexans nipponii) in 2016 (strain 16-0810-26) but not in 2017-2019. Six of 74 febrile horses in 2016 ...
Amat JP, Vergne T, Tapprest J, Ferry B, Hans A, Hendrikx P, Dufour B, Leblond A.Equine viral arteritis (EVA) may have serious economic impact on the equine industry. For this reason, it is monitored in many countries, especially in breeding stock, to avoid its spread during breeding activities. In France, surveillance is mainly based on serological tests, since mares are not vaccinated, but difficulties in interpreting certain series of results may impair the estimation of the number of outbreaks. In this study, we propose specific rules for identifying seroconversion in order to estimate the number of outbreaks that were detected by the breeding stock surveillance compon...
Gross DK, Morley PS, Hinchcliff KW, Reichle JK, Slemons RD.The purpose of this investigation was to determine if naturally occurring acute infectious upper respiratory disease (IRD) caused by equine influenza virus is associated with ultrasonographically detectable pleural and pulmonary abnormalities in horses. Standardbred racehorses were evaluated for signs of IRD, defined as acute coughing or mucopurulent nasal discharge. For every horse with IRD (n = 16), 1 or 2 horses with no signs of IRD and the same owner or trainer (n = 30) were included. Thoracic ultrasonography was performed within 5-10 days of the onset of clinical disease in horses with IR...
Brankston G, Rossi TM, O'Sullivan TL, Greer AL.This retrospective study describes testing patterns and the incidence of subsp. in Ontario to assess the utility of laboratory data for surveillance purposes. Laboratory records for equine infectious disease test submissions were extracted from the Animal Health Laboratory (AHL) at the University of Guelph for the years 2008 to 2018. Yearly and seasonal trends in testing and the proportion of tests that returned positive results were assessed. The number of samples submitted for testing decreased over the 11-year period (odds ratio = 0.96, 95% confidence interval: 0.92 to 0.999; = 0.04). ...
Senderska-Płonowska M, Zielińska P, Żak A, Stefaniak T.Heel contraction is an undesired but common condition in domestic horses. Some authors indicate shoeing as a risk factor. There is a correlation between shoeing and a restriction of heel expansion, but the clinical significance is unknown. This study aimed to evaluate the influence of shoeing and other risk factors, such as age, access to paddock, and breed, on heel contraction. This study included 114 horses, 55 of which were barefoot their whole life and 59 had been shod consistently for at least the previous year. The width and length of the frog were measured. Linear mixed-effects models w...
Collins JA, Hanlon A, More SJ, Wall PG, Duggan V.Ireland has long been renowned as a major centre for the breeding, rearing and keeping of horses. Since 2007, however, there has been increasing concern for horse health and welfare standards, and links between these concerns and the structures, governance and funding of the Irish equine industries have been reported. This paper addresses two central issues: firstly the local governance of, trade in and disposal of unwanted horses; and secondly mechanisms employed to improve standards of care given to horses owned by certain communities. Methods: Primary information was gathered through visits...
Tulloch JSP, Fleming KM, Pinchbeck G, Forster J, Lowe W, Westgarth C.Animal-related injuries pose a significant risk to the veterinary profession. This study aimed to describe the incidence, demographics, context and consequences of animal-related injuries at UK veterinary schools. A multicentre audit of accident records (2009-2018) across five UK veterinary schools was performed. Injury rates were stratified by school, demographics and species. The context and cause of the injury were described. Multivariable logistic models explored factors associated with medical treatment, hospital visits and time off work. An annual rate of 2.60 (95% confidence interval 2....
de Souza TC, Suthers JM, Busschers E, Burford JH, Freeman SL.Synovial sepsis is a frequent cause of morbidity and mortality in horses. Despite advances in diagnostics and treatments, persistent infection or chronic lameness can occur. Objective: To perform a scoping review to identify and evaluate the current evidence on the factors implicated in the success of treatment for synovial sepsis. Methods: Joanna Briggs Institute scoping review. Methods: A protocol was registered, and a systematic literature search was performed on CAB abstracts, Medline, Scopus and Embase. Inclusion and exclusion criteria were developed and studies systematically reviewed ag...
Stonehouse O, Stefanovski D, Bowman B, Sertich PL, Demchur J, Lewis GM, Turner RM, Turner RMO.Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from...
Lopez KM, Fleming GJ, Mylniczenko ND.Reports of equine herpesvirus (EHV) 1 and EHV-9 causing clinical disease in a wide range of species have been well documented in the literature. It is thought that zebras are the natural hosts of EHV-9 both in the wild and in captive collections. Concerns about potential interspecies transmission of EHV-1 and EHV-9 in a mixed species savannah exhibit prompted serologic and polymerase chain reaction surveys. Eighteen Burchell's zebras ( Equus quagga ), 11 Hartmann's mountain zebras ( Equus zebra hartmannae), and 14 Thomson's gazelles ( Eudorcas thomsonii ) cohabitating the same exhibit were exa...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kondo T, Matsumura T.Non-specific hemolysis has often been observed during complement-fixation (CF) tests for equine herpesvirus type-1 (EHV-1), even when the sera have virus-specific CF antibodies. This phenomenon has also been reported in CF tests for various infectious diseases of swine. We found that the sera from 22 of 85 field horses (25.9%) showed non-specific hemolysis during conventional CF testing for EHV-1. Because pretreatment of swine sera with potassium periodate (KIO4) improves the CF test for swine influenza, we applied this method to horse sera. As we expected, horse sera treated with KIO4 did not...
Trachsel DS, Drozdzewska K, Bergmann F, Ziegler U, Gehlen H.West Nile virus (WNV) is a mosquito-borne viral pathogen of global importance and is considered to be the most widespread flavivirus. In Germany, first infections with WNV were detected in 2018 and it is expected for these to become more frequent in consequence to warmer winters followed by a rainy/humid springtime. WNV is maintained in an enzootic cycle between ornithophilic mosquitoes and certain wild bird species. Humans and horses are so-called "dead-end hosts" of a WNV infection. They frequently do not fall ill, however occasionally develop overt infections ranging from mild febrile sympt...
Labeda DP, Price NP, Kroppenstedt RM, Donahue JM, Williams NM, Sells SF.Two actinomycete strains, NRRL B-24165(T) and NRRL B-24166(T), isolated from lesions on equine placentas in Kentucky, USA, were analysed using a polyphasic taxonomic approach. On the basis of phylogenetic analysis of 16S rRNA gene sequences, morphological observations and the presence of ll-diaminopimelic acid as the diagnostic diamino acid in whole-cell hydrolysates, the new isolates clearly belonged to the genus Streptomyces. Analyses of the phylogenetic positions of strains NRRL B-24165(T) and NRRL B-24166(T) based on 16S rRNA gene sequences of all recognized species of the genus Streptomyc...
Freeman DE, Spencer PA.Age, breed, and gender distributions of 168 horses with umbilical hernia treated at the University of Pennsylvania School of Veterinary Medicine were analyzed to determine risk factors for this disease. For the 3 breeds that constituted the largest proportion of hospital and case populations, Thoroughbred, Standardbred, and Quarter Horse, the overall ratio of females to males was 1.63. In a hospital population of the same age group, 0 to 48 months, the female to male ratio was 0.93. Compared with males, females were at significantly higher risk for umbilical hernia after adjustment for breed a...
Wesley IV, Schroeder-Tucker L.The genus Arcobacter encompasses campylobacter-like organisms that grow in air at 25 degrees C. Arcobacter has been detected or isolated from clinically healthy livestock as well as aborted fetuses and has been presumptively identified as either Campylobacter or Leptospira, based on its growth in selective semisolid media. Because reports from nonlivestock species are limited, this study examined nine presumptive isolates of Arcobacter spp. from an alpaca (Vicugna pacos), black rhinoceros (Diceros bicornis), white rhinoceros (Ceratotherium simum), gorilla (Troglodytes gorilla), gazelle (Eudorc...
Reeves WK, Miller MM.Organic insect repellents are of interest to many agricultural producers and animal owners. Geraniol, a plant-derived alcohol, is naturally produced by a wide range of plants and is a US Environmental Protection Agency minimum risk pesticide. Previous studies have shown various concentrations of geraniol repel or kill mosquitoes; however, geraniol might cause allergic contact dermatitis in humans or animals. We tested a commercially available 2% aqueous solution of geraniol on ponies as a mosquito repellent. Five trials were conducted on ponies treated with a 60-ml aerosol mist (30 ml per side...
Ramsay JD, Evanoff R, Mealey RH.Hepacivirus A (also known as nonprimate hepacivirus and equine hepacivirus) is a hepatotropic virus that can cause both transient and persistent infections in horses. The evolution of intrahost viral populations (quasispecies) has not been studied in detail for hepacivirus A, and its roles in immune evasion and persistence are unknown. To address these knowledge gaps, we first evaluated the envelope gene (E1 and E2) diversity of two different hepacivirus A strains (WSU and CU) in longitudinal blood samples from experimentally infected adult horses, juvenile horses (foals), and foals with sever...
Léon A, Versmisse Y, Despois L, Castagnet S, Gracieux P, Blanchard B.Isolation and identification of Taylorella equigenitalis, the causative agent of contagious equine metritis, by bacteriology is laborious and does not permit differentiation from the other member of the genus, Taylorella asinigenitalis. Moreover, other organisms such as Klebsiella pneumoniae and Pseudomonas aeruginosa can also cause endometritis in mares and warrant diagnostic detection. Our objectives were to develop a rapid preparation method for field swab samples and to validate this protocol using new multiplex real-time polymerase chain reaction (rtPCR) detection tools for identification...
Gould JC, Rossano MG, Lawrence LM, Burk SV, Ennis RB, Lyons ET.Parascaris equorum generally infects horses less than 18 months old and its pathological effects can be severe. Infection occurs when larvated eggs, present in pastures, paddocks, stalls, and on feeding and watering equipment are ingested. The purpose of this study was to examine the effects of windrow composting on the viability of P. equorum eggs at a cooperating central Kentucky horse farm. Three grams of feces containing 2216 P. equorum eggs per gram were sealed in filter bag sentinel chambers. Chambers were exposed to 1 of 3 treatments: constant exposure or intermittent exposure to the in...
Williams NJ, Slovis NM, Browne NS, Troedsson MHT, Giguėre S, Hernandez JA.Diarrhea remains an important cause of morbidity and mortality in neonatal foals, and correct identification of etiologic agents is essential for effective disease management. Objective: To examine the association between diarrhea and detection of Enterococcus durans or other enteropathogens in neonatal foals on 1 breeding farm in Kentucky, USA. Methods: Fifty-nine Thoroughbred foals and their broodmares. Methods: Prospective observational study. Study foals and broodmares were sampled and tested for E. durans and other enteropathogens during the first 10 days after foaling. The frequency of...
Boersema JH, Borgsteede FH, Eysker M, Elema TE, Gaasenbeek CP, van der Burg WP.A survey to determine the prevalence of anthelmintic resistance of horse strongyles was carried out with 616 horses on 22 farms. The tested drugs were cambendazole, pyrantel pamaote and ivermectin. Based on egg count reduction tests the efficacy of cambendazole varied from 0% to 93% and of pyrantel from 93% to 100%. Ivermectin treatments were 100% effective on all farms. Larval cultures after cambendazole treatments revealed exclusively cyathostome larvae. After pyrantel treatments besides cyathostome larvae other types of larvae were also found. After ivermectin treatments only a few cyathost...
Chapuis RJJ, Ragno VM, Ariza CA, Movasseghi AR, Sayi S, Uehlinger FD, Montgomery JB.In the summer of 2017, 4 horses were diagnosed with septic fibrinous pericarditis at the Western College of Veterinary Medicine, Saskatoon. This case series occurred after a significant outbreak of forest tent caterpillars in the province during that spring. Three horses were immediately euthanized, and treatment was attempted in 1 mare. This is the first case series of pericarditis possibly associated with the ingestion of forest tent caterpillars to be reported in western Canada. Although cause-effect is not proven, it is prudent to prevent the ingestion of caterpillars by horses. Key clini...
Mazzei M, Savini G, Di Gennaro A, Macchioni F, Prati MC, Guzmàn LR, Tolari F.West Nile virus (WNV) is a mosquito-borne virus belonging to the family Flaviviridae included in the Japanese encephalitis antigenic complex (JEAC). A seroepidemiological study was carried out in 2011 using 160 horse sera collected from different areas of Bolivia to investigate the presence of WNV antibody. A high proportion (59.4%) of the tested sera were positive to a commercially available WNV competitive enzyme-linked immunosorbent assay (C-ELISA). Sixty-six randomly selected C-ELISA-positive sera were further tested by WNV plaque reduction neutralization test (PRNT), virus neutralization ...
Bartosik J, Łojek J, Długosz E, Górski P, Zygner W.Tapeworm infections in Konik Polski horses from Biebrza National Park were investigated in this study. Faecal samples were collected 10 times: in 2012 - 1 time, in 2013 - 4 times, in 2014 - 4 times and in 2015 - 1 time. In total, 162 faecal samples were collected and tested. Faecal egg counts (FECs) method was used in the study. Positive samples with cestode eggs were noted only twice - in October 2012 and December 2013 in two adult mares (9 and 11 years old). The determined prevalence was surprisingly low comparing to other studies, 4.3% in October 2013 and 28.5% in December 2013. Parasite ge...
Downs JA, Hyzer G, Marion E, Smith ZJ, Kelen PV, Unnasch TR.Eastern equine encephalitis (EEE) is a mosquito-borne viral disease that is often fatal to humans and horses. Some species including white-tailed deer and passerine birds can survive infection with the EEE virus (EEEV) and develop antibodies that can be detected using laboratory techniques. In this way, collected serum samples from free ranging white-tailed deer can be used to monitor the presence of the virus in ecosystems. This study developed and tested a risk index model designed to predict EEEV activity in white-tailed deer in a three-county area of Michigan. The model evaluates EEEV risk...
Montes-Cortés MG, Fernández-García JL, Martínez-Estéllez MÁH.Equine piroplasmosis is caused by two haemoprotozoan parasites: and . Negative economic impact on international trade has been associated to endemic sites. This is the reason why carrier detection requires reliable diagnostic methods. Various diagnostic modalities can be used alone or in combination including PCR. However, genetic variation of commonly used genes is still of debate. The aim of this research was to sequence the β-tubulin gene of a strain from Spain and to compare it with known β-tubulin sequences. Methods: DNA was isolated from a cryopreserved strain from Spain and acute an...