Disease management in horses encompasses the strategies and practices employed to prevent, control, and treat diseases affecting equine populations. This field involves understanding the etiology, transmission, and clinical presentation of various equine diseases, as well as implementing biosecurity measures and therapeutic interventions. Common diseases in horses include equine influenza, strangles, and equine herpesvirus. Effective disease management relies on accurate diagnosis, vaccination protocols, and the use of antimicrobials and other treatments. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, challenges, and advancements in managing diseases in equine health.
Hutchens DE, Paul AJ, DiPietro JA.Routine anthelmintic treatments are one of the most important components of an equine wellness program used by horse owners and veterinarians today. Thirteen different compounds are available in the United States in the treatment of gastrointestinal parasites, most of which are available over the counter. As a result, there is a decreased reliance on the veterinarian to perform routine tube dewormings. Therefore, the future of the veterinarian's role in the management of gastrointestinal parasites is likely to be in the consultation and design of parasite control programs. With this in mind, t...
Whittem T.This article presents in easily accessible form a collection of drug names and dose rates for the drugs recommended or referred to by the authors of the individual articles in this issue. Although the formulary provides recommendations for drug use, the reader is cautioned that the responsibility for the choice of agent, formulation, dose, and dose interval lies with the clinician. The author also addresses regulations that govern the use of drugs in competition horses.
Mogg TD.Cardiac disease is often life-threatening and challenging to treat. Prolonged therapy is indicated in many cases, which can lead to problems with treatment costs, owner compliance, and potential drug toxicity. Many therapies are empirical or based on data from other species because of a lack of well-designed prospective clinical trials in horses. This article reviews the clinical pharmacology and therapeutics of heart failure, cardiac arrhythmias, myocardial disease, endocarditis, and pericardial disease.
al-Ani FK.Epizootic lymphangitis is a relatively common infectious disease of horses and other liquids in certain parts of the world. The infection rate varies according to the geographic area and the age of the animal. The disease is most commonly characterised by a cord-like appearance of the subcutaneous lymphatic and cutaneous pyogranulomas, the discharge from which contains spherical or pear-shaped bodies of the causal agent, Histoplasma farciminosum. Diagnosis can be made by the demonstration of typical organisms in stained smears, culture and tissue sections. Serological tests and a skin hypersen...
Portas M, Boinas FS, Oliveira E Sousa J, Rawlings P.African horse sickness (AHS) was diagnosed for the first time in southern Portugal in autumn 1989, following outbreaks in Spain. AHS virus presence was confirmed by virus isolation and serotyping. An eradication campaign with four sanitary zones was set up by Central Veterinary Services in close collaboration with private organizations. Vaccination began on 6 October. In February 1990, vaccination was extended to all Portuguese equines (170000 animals). There were 137 outbreaks on 104 farms: 206 of the equidae present died (16%) or were slaughtered (14%); 81.5% were horses, 10.7% were donkeys ...
Newton JR, Wood JL, Castillo-Olivares FJ, Mumford JA.Serological analysis of blood samples submitted to the Animal Health Trust showed that during 1995, 185 of 9203 unvaccinated horses (2.0 per cent) tested positive for antibodies to equine arteritis virus (EAV), and that during 1996, 46 of 8851 unvaccinated horses (0.52 per cent) tested positive. During both years thoroughbreds were the predominant breed tested and only a small proportion of these (<0.3 per cent), consisting predominantly of imported mares, were seropositive. In contrast, among standardbred horses, from which samples were actively solicited in 1995, 84 of 454 (18.5 per cent) we...
Smyth DA, Baptiste KE, Cruz AM, Naylor JM.A 6-year-old, 420-kg quarter horse gelding was presented with a 2-month history of difficulty swallowing and dyspnea. The horse was diagnosed with a right guttural pouch empyema with many large chondroids. Two surgeries were required to completely remove all the chondroids from what proved to be a primary distension of the guttural pouch lateral compartment.
Freeman DA, Cymbaluk NF, Schott HC, Hinchcliff K, McDonnell SM, Kyle B.To compare health, hydration status, and management of stabled pregnant mares provided drinking water continuously or via 1 of 3 intermittent delivery systems. Methods: 22 Quarter Horse (QH) or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 1); 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2). Methods: Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Body temperature, attitude, appetite, water intake, and urine output were recorded daily. Hygiene of ea...
Kerber CE, Ferreira F, Pereira MC.The importance of equine piroplasmosis control in endemic countries has increased in recent years and plays an important role to maintain the international market open to the horse industry. The purpose of this study was to demonstrate the occurrence of equine piroplasmosis (Babesia equi or Theileria equi and Babesia caballi) in Brazil--a country where the disease occurs endemically--in different climatic conditions, and to evaluate the results of a strategy for tick control in order to decrease infection rates. Blood samples were taken from 720 horses on 28 farms from different regions and su...
el-Banna HA.The pharmacokinetic aspects of sulphadimidine were studied in clinically healthy (control) and Flunixin-medicated horses after a single intravenous and oral administration of 100 mg/kg body weight. Plasma sulphadimidine concentration were determined by high-performance liquid chromatography (HPLC). Following the intravenous injection, all plasma sulphadimidine data were best approximated by a two-compartment open model using sequential, weight non-linear regression. Flunixin induced a 67% increase in the rate of sulphadimidine return to the central compartment from peripheral tissues (K21) and...
Brault AC, Powers AM, Chavez CL, Lopez RN, Cachón MF, Gutierrez LF, Kang W, Tesh RB, Shope RE, Weaver SC.Eastern equine encephalitis virus (EEEV), the sole species in the EEE antigenic complex, is divided into North and South American antigenic varieties based on hemagglutination inhibition tests. Here we describe serologic and phylogenetic analyses of representatives of these varieties, spanning the entire temporal and geographic range available. Nucleotide sequencing and phylogenetic analyses revealed additional genetic diversity within the South American variety; 3 major South/Central American lineages were identified including one represented by a single isolate from eastern Brazil, and 2 lin...
Vredevoe LK, Richter PJ, Madigan JE, Kimsey RB.This study was conducted to determine if the biology of certain ticks associated with horses regulates the spatial and temporal distribution of equine granulocytic ehrlichiosis (EGE) in California north of Monterey County. We compared the spatial and temporal distribution of EGE cases with the seasons of activity and life histories of ticks that infest horses. Spatially, cases collected from equine veterinarians clustered around each other in a manner different from the way in which control cities of practice were distributed, with foci limited to the Sierra Nevada and coastal foothills. Cases...
Ambawat HK, Malhotra DV, Kumar S, Dhar S.Equine babesiosis, caused by Babesia equi and transmitted by ticks is of major economic importance in India. The adverse effects which B. equi organism and its metabolites inflict on red blood cells have not been reported. Erythrocytes were analysed for red cell membrane phospholipids, proteins and haemoglobin (Hb) concentration and plasma for malondialdehyde (MDA) in B. equi carrier donkeys before splenectomy (50% parasitaemia. Before splenectomy the mean values of membrane protein, phospholipids, plasma MDA and Hb were found to be 1.63 +/- 0.12 mg/ml PCV, 2.28 +/- 0.9 mg/ml PCV, 3.63 +/- 0.3...
Silva AV, Costa HM, Santos HA, Carvalho RO.Thirty six horses from nine Brazilian states (Goiás, Minas Gerais, Pará, Maranhão, Piauí, Paraíba, Pernambuco, Rio Grande do Norte, and Ceará) were examined for infections by small strongyles. The following species were identified: Cylicocyclus nassatus, C. insigne, C. brevicapsulatus, C. leptostomum, C. radiatus, C. ultrajectinus, C. ashworthi, Cylicostephanus goldi, C. calicatus, C. minutus, C. longibursatus, Petrovinema poculatum, Coronocyclus coronatus, C. labiatus, C. labratus, Cyathostomum catinatum, C. pateratum, C. alveatum, Parapoteriostomum euproctus, Cylicodontophorus bicorona...
Sangster NC.Anthelmintic-resistance has emerged as a problem in several animal industries. In the horse, cyathostome resistance to all available treatments except for the avermectin/milbemycins means that these drugs provide the cornerstone of control. Ivermectin has been available for several years; the related compound moxidectin is more recent. Although we do not know for sure, aspects of moxidectin such as its persistent action and its efficacy against mucosal stages of cyathostomes, may enhance the rate of development of resistance. On the other hand, selection pressure would be reduced if the persis...
Young KE, Garza V, Snowden K, Dobson RJ, Powell D, Craig TM.Diversity of parasite populations was compared between two herds of horses, one a regularly treated herd the other a feral herd which has bad no anthelmintic treatment for at least 25 years. Eggs obtained from fecal samples of both herds were tested for anthelmintic resistance by use of an in-vitro larval hatch/development assay (LDA), DrenchRite. A fecal egg reduction test was also performed with the domesticated herd using fenbendazole, pyrantel pamoate and ivermectin. Cyathostomes were the predominant group of worms present in both herds. Trichostrongylus axei was seen in both herds, but St...
Lyons ET, Tolliver SC, Drudge JH.Small strongyles are highly prevalent in horses and can be found worldwide. Even though over 50 species of these parasites have been described, about 10 species comprise the bulk of the total number present in horses. Efforts to control small strongyles and other equine internal parasites have been undertaken for many years. Some of the early medications and control measures provided questionable activity against endoparasites; whether effective or not, they could be detrimental to the horse. Beginning in the early 1900s, scientific effort was used to evaluate activity of antiparasitic compoun...
Krecek RC, Guthrie AJ.Cyathostomes are common nematode parasites of horses, donkeys and mules in developing countries. These equids usually work on a daily basis and this includes transportation of goods, crops and people. Stress, associated with work, and limited nutrition often result in a loss of condition, and cyathostomid nematodes may, then, cause clinical disease. Because anthelmintics are not always accessible or affordable in many parts of Africa, or there may be anthelmintic resistance to current remedies, management practices are often used as an adjunct to chemotherapy. This paper discusses some current...
Reinemeyer CR.Efforts to control cyathostome nematodes in temperate climates have not been uniformly successful, as evidenced by contemporary reports of clinical disease and widespread anthelmintic failure. Indeed, effective control is confounded by numerous factors, including ignorance of local transmission patterns, confusing or conflicting control recommendations, and use of ineffective anthelmintics or regimens. Most of these problems are universal rather than being climatically unique, and it is important to recognize that they are mere symptoms of larger and more comprehensive problems. The most basic...
Brumbaugh GW, Sumano López H, Hoyas Sepúlveda ML.Each horse with laminitis is presented to the veterinarian at a different stage in progression of the condition and with varying severity. The pathogenic timing is often unknown and is difficult to determine. Because timing and severity are related to both the lesion's severity and responsiveness to treatment, these factors are critical to treatment selection and success. It is erroneous to assume that each horse with laminitis should receive each treatment. It is therefore important to ascertain as logically and objectively as possible the pathophysiological stage of development of each horse...
Glanville RJ, Christie B.The equine influenza (EI) outbreak presented many challenges that required high-level coordination and decision making, as well as the development of new approaches for satisfactory and consistent resolution. This paper outlines the elements of the national coordination arrangements, preparatory arrangements in place prior to the outbreak that facilitated national coordination, and some of the issues faced and resolved in the response.
Firth EC, Alley MR, Hodge H.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.
Tschetter JR, Blikslager AT, Little D, Howard RD, Woody SL, Beex LM, Crisman MV.Colic is a serious disease syndrome in horses. Much of the mortality is associated with ischaemic-injured intestine during strangulating obstruction, yet there is limited understanding of the associated molecular events. Identification of differentially expressed genes during ischaemic injury should expand our understanding of colic and may lead to novel targeted therapeutic approaches in the future. Objective: To isolate and identify differentially expressed genes in equine jejunum following a 2 h ischaemic event compared to normally perfused jejunum. Methods: Suppressive subtractive hybridis...
Recent outbreaks of equine infectious anaemia and equine viral arteritis in the UK. Update on the equine infectious anaemia situation in Europe. West Nile virus reported in several Mediterranean countries. Current and future approaches to equine viral arteritis control in the UK. These are among matters discussed in the quarterly equine disease surveillance report for April to June 2010, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
Wallace J.With concerns growing globally about anthelmintic resistance in equine endoparasites, James Wallace's practice undertook some research among its horse-owning clients and introduced a fixed-fee parasite management programme to help ensure the most effective use of these valuable medicines.
Salas-Romero J, Gómez-Cabrera KA, Aguilera-Valle LA, Bertot JA, Salas JE, Arenal A, Nielsen MK.Increasing levels of anthelmintic resistance observed in equine cyathostomin parasites have led to recommendations of selective anthelmintic treatment strategies to lower the selection pressure favoring resistant populations. This principle is based on determining strongyle fecal egg counts from all herd members, and treating those exceeding a predetermined treatment cutoff. However, epidemiological information is lacking from horses kept under tropical conditions, where parasite burdens may be of a different composition and magnitude compared to those of horses kept under temperate climate co...
DiPietro JA, Todd KS, Reuter V.Four groups of 10 horses (mares) each were treated with a 1% solution of ivermectin (200 micrograms/kg of body weight) in a propylene glycol-glycerol formal base orally, a 1% solution of ivermectin (200 micrograms/kg) in a propylene glycol-glycerol formal base via nasogastric tube, a 1.87% paste of ivermectin (200 micrograms/kg) orally, or a 22.7% paste of oxibendazole (10 mg/kg) orally. Fecal examinations were done before treatment and on posttreatment days (PTD) 14, 28, 42, 56, and 70. Strongyle egg per gram counts and sugar flotation fecal examinations were performed. Results of fecal exami...
Palmer JE, Benson CE, Whitlock RH.Salmonella was isolated from 13 of 100 colicky horses admitted to a referral hospital. Seven horses were shedding the microorganism at or soon after hospital admission. A unique serotype was introduced into the hospital by a horse not shedding Salmonella at admission. It was concluded that 8 horses were infected before admission. Whether the remaining 5 horses were infected before or after admission could not be determined. Salmonella senftenberg was the most commonly isolated serotype from colicky horses and from horses with salmonellosis that were not colicky on hospital admission during the...
Lochner HL, Martinson KL, Bianco AW, Hutchinson ML, Wilson ML, Johnston LJ, Dentzman KE.Challenges associated with burial, rendering, and cremation have forced horse owners to seek alternative mortality disposal methods. While equine mortality composting has been successfully demonstrated, industry-wide adoption has been limited. Therefore, evaluation of horse owners' and veterinarians' perceptions and experience with mortality composting is needed. Two surveys were developed to evaluate industry practices and decisive factors regarding equine euthanasia and mortality disposal methods. Each survey was designed for a separate audience: horse owners or veterinarians serving equines...
Bishop R, Dzanis DA.This article provides reviews of the following: principal regulatory frameworks governing the supply of feed products for horses, focusing on the United States and Europe with guidance on compliance; key federal, state, or country requirements to ensure safe and accurately labeled products; rules concerning antidoping with a review of naturally occurring prohibited substances commonly found in feedstuffs; essential information for brand holders of equine nutrition products, practicing veterinarians, independent nutritionists, research scientists, competition riders and racehorse trainers, and ...
Gibson MJ, Legg KA, Gee EK, Rogers CW.After establishing a baseline of stipendiary stewards' reporting using the paper-based system in the 2015/16 and 2016/17 seasons of harness racing, it is important to examine if the implementation of an online system has altered frequency and descriptors used for clinical outcomes. The objective of this study was to describe the race level injury and reporting outcomes, and horse- and race-level variables associated with the rate of the reporting of these outcomes during the 2019/20 and2020/21 harness racing seasons in New Zealand. The introduction of the online system was associated with few ...
Steward ML.This article describes the use of the wooden shoe in the treatment of chronic laminitis. The shoe, designed to provide a solid base and full roller motion, offers mechanical advantages and enables reduction and redistribution of forces within the hoof capsule.
Braverman Y.The feasibility of using infra-red thermography for early and out of season detection of summer seasonal recurrent dermatitis (sweet itch) was tested on 13 sensitive and six insensitive horses in Israel. In summer (June, July and September) six affected mares and two unaffected sensitive mares (one of them a pony) were clearly 'warmer' in the affected zones than three insensitive mares. In winter (February and March) unaffected sensitive horses could be differentiated from insensitive mares by the warm areas detected in the affected zones. Small numbers of Culicoides imicola bites may have bee...
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...
Toews AR, Campbell JR.To assess the value of CBC as a preoperative test in healthy horses undergoing cryptorchidectomy. Methods: Retrospective study. Methods: 117 horses. Methods: Medical records were reviewed to identify horses that had had cryptorchidectomy. Of the 117 horses identified, 102 were found that did not have a known medical condition believed to adversely affect surgery. Preoperative CBC was assessed in terms of abnormalities detected and effects of these abnormalities on development of complications during and after surgery and patient management. Results: Of 102 CBC performed, 55 contained abnormali...
Hughes K.Cases of Hendra virus infection in horses in Australia have been seen regularly since the virus was first isolated in 1994. Kristopher Hughes, associate professor of equine medicine at Charles Sturt University in Australia, gives an overview of how knowledge of the virus has developed in the past 20 years.