Prophylaxis in horses refers to the preventive measures and strategies implemented to protect equine health by reducing the risk of disease occurrence. These measures can include vaccinations, parasite control, nutrition management, and biosecurity practices. Vaccinations help to stimulate the horse's immune system to protect against specific infectious diseases. Parasite control programs aim to minimize the impact of internal and external parasites through strategic deworming and environmental management. Nutrition management ensures that horses receive balanced diets that support their overall health and immune function. Biosecurity practices involve procedures to prevent the introduction and spread of infectious agents within equine populations. This page gathers peer-reviewed research studies and scholarly articles that explore various prophylactic approaches, their implementation, and their effectiveness in maintaining equine health.
Recchi L, Cribb N, Côté N, Dubois MS, Koenig J, Valverde A, Monteith G.Antimicrobial stewardship has shown significant development in recent years. Perioperative prophylaxis accounts for a substantial volume of antimicrobial use and is a field in which improvements can likely be made. The objective of this study was to evaluate practices associated with perioperative antimicrobial use in equine elective laparoscopy at a single institution over a 21-year period and to determine whether antimicrobial therapy influenced the occurrence of postoperative complications. Medical records of horses that underwent elective laparoscopy at a teaching hospital from January 200...
Bacci S, Meucci V, Sgorbini M, De Marchi L, Pirone A, Pretti C, Tognetti R, Intorre L.Antimicrobial prescriptions of the University of Pisa and their compliance with prudent use recommendations were investigated over 11 years (2011-2021). At least one antimicrobial was always prescribed in surgical prophylaxis for the suture of wounds and in 33% of horses with signs of disease of a body system. Antimicrobials were administered in monotherapy (48%) in fixed dose combinations (21%) and empirical combinations (31%). Antimicrobials were mostly (63%) administered by parenteral route, while oral and topical antimicrobials accounted for 14% and 23% of prescriptions, respectively. Gen...
Kauter A, Brombach J, Lübke-Becker A, Kannapin D, Bang C, Franzenburg S, Stoeckle SD, Mellmann A, Scherff N, Köck R, Guenther S, Wieler LH....Horse clinics are hotspots for the accumulation and spread of clinically relevant and zoonotic multidrug-resistant bacteria, including extended-spectrum β-lactamase producing (ESBL) Enterobacterales. Although median laparotomy in cases of acute equine colic is a frequently performed surgical intervention, knowledge about the effects of peri-operative antibiotic prophylaxis (PAP) based on a combination of penicillin and gentamicin on the gut microbiota is limited. Unassigned: We collected fecal samples of horses from a non-hospitalized control group (CG) and from horses receiving either a pre-...
Hoblick S, Denagamage TN, Morton AJ, McCarrel TM.Post-anaesthetic fever is a known complication of general anaesthesia, however, its incidence in horses undergoing elective magnetic resonance imaging (MRI) is unknown. Objective: To determine the incidence of post-anaesthetic fever in horses undergoing elective orthopaedic MRI and determine whether prophylactic antimicrobial therapy would be associated with a reduction in the incidence of post-anaesthetic fever. We hypothesised that prophylactic antimicrobials would be associated with a reduction in the incidence of post-anaesthetic fever. Methods: Retrospective cross-sectional study. Methods...
Lavado RA, Lewis J, Montgomery JB.Laminitis is a severely debilitating and life-threatening condition that occurs as a consequence of different primary triggering factors. Continuous digital hypothermia (CDH) is recommended in horses at risk of, or diagnosed with, acute laminitis due to its several physiological and biochemical alterations that may be positive for the prevention and early treatment of the condition, representing a low risk of adverse effects. Modulation of the inflammatory response, profound vasoconstriction, and prevention of tissue damage are the most notable protective effects of cryotherapy on the lamellae...
Kinoshita Y, Yamanaka T, Kodaira K, Niwa H, Uchida-Fujii E, Ueno T.A two-dose revaccination against tetanus is recommended for horses over 2 years old in Japan with no history of vaccination in the previous year. Here, the need for two-dose revaccination was evaluated in terms of antibody titers for each vaccine type, namely monovalent or multivalent. There was no difference in antibody titers between one- and two-dose regimens for up to 1 year, except at 8 weeks with the multivalent vaccine, and all horses had sufficient antibody titers for 1 year of tetanus prophylaxis. These results suggest that one-dose revaccination, regardless of the vaccine type, is as...
Rockow M, Griffenhagen G, Landolt G, Hendrickson D, Pezzanite L.In the past decade, there has been a considerable increase in the recognition of antimicrobial resistance in equine practice. The objective of this study was to survey the current clinical use of antimicrobials for a commonly performed surgical procedure (exploratory celiotomy) with the goal of understanding how recent literature and changes in microbial resistance patterns may have impacted antimicrobial selection practices. An electronic survey was distributed to veterinary professionals within the American College of Veterinary Internal Medicine (ACVIM) and the American College of Veterinar...
Cao X, Yang D, Parvathareddy J, Chu YK, Kim EJ, Fitz-Henley JN, Li X, Lukka PB, Parmar KR, Temrikar ZH, Dhole P, Adcock RS, Gabbard J, Bansal S....Venezuelan and eastern equine encephalitis viruses (VEEV and EEEV, respectively) are mosquito-borne, neuroinvasive human pathogens for which no FDA-approved therapeutic exists. Besides the biothreat posed by these viruses when aerosolized, arthropod transmission presents serious health risks to humans, as demonstrated by the 2019 outbreak of EEE disease in the United States that resulted in 38 confirmed cases, 19 deaths, and neurological effects in survivors. Here, we describe the discovery of a 2-pyrrolidinoquinazolinone scaffold, efficiently synthesized in two to five steps, whose structural...
Söderroos D, Ignell R, Haubro Andersen P, Bergvall K, Riihimäki M.Insect bite hypersensitivity (IBH) associated with biting midges is a common allergic skin disease in horses, reducing the welfare of affected horses. This study investigated the effect of IBH on animal welfare and behaviour and assessed a new prophylactic insect repellent. In total, 30 horses were recruited for a prospective cross-over and case-control study. Clinical signs of IBH, inflammatory markers in skin biopsies and behavioural data (direct observations, motion index) were scored longitudinally during two consecutive summers. No differences were observed in the total number of itching...
Persistent post-breeding induced endometritis (PPBIE) is considered a major cause of subfertility in mares. It consists of persistent or delayed uterine inflammation in susceptible mares. There are many options for the treatment of PPBIE, but in this study, a novel approach aimed at preventing the onset of PPBIE was investigated. Stallion semen was supplemented with extracellular vesicles derived from amniotic mesenchymal stromal cells (AMSC-EVs) at the time of insemination to prevent or limit the development of PPBIE. Before use in mares, a dose-response curve was produced to evaluate the eff...
Carnet F, Perrin-Cocon L, Paillot R, Lotteau V, Pronost S, Vidalain PO.Vaccination is one of the most widely used strategies to protect horses against pathogens. However, available equine vaccines often have limitations, as they do not always provide effective, long-term protection and booster injections are often required. In addition, research efforts are needed to develop effective vaccines against emerging equine pathogens. In this review, we provide an inventory of approved adjuvants for equine vaccines worldwide, and discuss their composition and mode of action when available. A wide range of adjuvants are used in marketed vaccines for horses, the main fami...
Singh S, Kumar B, Dilbaghi N, Devi N, Prasad M, Manuja A.Isometamidium chloride (ISM) is a trypanocide for the prophylactic and therapeutic use against vector-borne animal trypanosomosis (mainly Surra caused by ) and African animal trypanosomosis caused by //). ISM was found to be an efficient trypanocide for therapeutic/prophylactic use against trypanosomosis; however, it produces some local and systemic detrimental effects in animals. We synthesized isometamidium chloride-loaded alginate gum acacia nanoformulation (ISM SANPS) to lessen the detrimental side effects of isometamidium chloride (ISM) while treating trypanosomal diseases. We intended to...
Carnet F, Paillot R, Fortier C, Hue ES, Briot L, de Geoffroy F, Vidalain PO, Pronost S.Equine influenza virus (EIV) is responsible for recurring outbreaks that are detrimental to the equine industry. Vaccination is key for prevention, but the effectiveness and duration of protection provided by existing vaccines is often insufficient. In order to improve vaccine efficacy, we evaluated the benefit of immune stimulation with inactivated Parapoxvirus ovis (iPPVO) on the antibody response induced by a vaccine boost against EIV. A whole inactivated ISCOMatrix-adjuvanted equine influenza vaccine was administered alone ( = 10) or combined with iPPVO injections at D0, D2 and D4 post vac...
Fukushi N, Fukushi H.Equine herpesvirus type 1 (EHV-1) is a devastating pathogen of horses, their natural hosts, and causes fatal encephalitis in non-natural hosts. We previously demonstrated that acylation of the tegument protein UL11 is required for viral replication in cultured cells. We created a mutant virus (EHV-1 UL12 trunc UL11 G2AC7AC9A), in which glycyl and cysteinyl residues at positions 2, 7 and 9 of UL11 that are normally acylated were replaced with alanyl residues. This virus, designated the 2/7/9 mutant, has a limited-replication cycle (LRC), in which replication stops after just a few cycles. Here,...
Pusterla N, Vaala W, Bain FT, Chappell DE, Craig B, Schneider C, Barnett DC, Gaughan E, Papich MG.Equine protozoal myeloencephalitis (EPM) has remained a devastating neurological disease of the Americas, especially in young performance horses. Prophylactic treatment strategies with diclazuril have shown to reduce seroprevalence and titer levels to Sarcocystis neurona in healthy horses continuously exposed to the apicomplexan parasite. The goal of this study was to determine if the FDA-labeled dose of 1 mg/kg of 1.56% diclazuril (Protazil) given once weekly to healthy adult horses would achieve steady-state concentrations in plasma known to be inhibitory to S. neurona in cell culture. Five ...
Byrne CA, Hotchkiss JW, Barakzai SZ.To document variations in the application of equine prosthetic laryngoplasty among equine surgeons. Methods: Cross-sectional survey. Methods: Six hundred and seventy-eight equine surgeons performing prosthetic laryngoplasty. Methods: An online questionnaire was sent to equine surgeons, including diplomates of the American College of Veterinary Surgeons and European College of Veterinary Surgeons. Questions focused on participant profile, surgical technique, antimicrobial therapy, and concurrent procedures. Descriptive statistical analysis was performed on the survey output. Results: Complete r...
Stefansdottir SB, Jonsdottir S, Kristjansdottir H, Svansson V, Marti E, Torsteinsdottir S.Insect bite hypersensitivity (IBH) is a seasonal dermatitis of horses caused by IgE-mediated reactions to bites of Culicoides midges characterized by an imbalance of T-cell subsets. Iceland is free of the causative species but the prevalence of IBH in exported Icelandic horses is especially high. We have shown that intralymphatic (i.l.) vaccination with r-Culicoides allergens in Aluminum hydroxide (alum) and monophosphoryl lipid A (MPLA) adjuvants induces a desired Th1/regulatory T-cell response. The aim of this study was to compare i.l. to subcutaneous (s.c.) injection. Twelve healthy Iceland...
Gandini M, Cerullo A, Franci P, Giusto G.Reducing postoperative incisional infection is the main reason to administer postoperative antimicrobials (AMD) after emergency laparotomy in horses, while reducing inflammation and providing analgesia are the reasons to administer anti-inflammatory drugs (AID). The basis for postoperative AMD and AID administration is empirical and only recently has been questioned. Empirical approaches can be changed, and these changes, along with the description of their outcomes, can help produce appropriate stewardship. The aim of this study is to report the changes in AMD and AID regimens in horses under...
Ohta M, Kambayashi Y, Mita H, Kuroda T, Bannai H, Tsujimura K, Yamanaka T, Garvey M, Cullinane A, Yamayoshi S, Kawaoka Y, Nemoto M.Updating vaccine strains is essential to control equine influenza. We evaluated the protective efficacy of an inactivated equine influenza vaccine derived from viruses generated by reverse genetics (RG) in horses in an experimental viral challenge study. Wild-type (WT) virus (A/equine/Tipperary/1/2019) and virus generated by RG (consisting of hemagglutinin and neuraminidase genes from A/equine/Tipperary/1/2019 and six other genes from high-growth A/Puerto Rico/8/34) were inactivated by formalin for vaccine use. Twelve 1-year-old naïve horses with no antibodies against equine influenza virus w...
Navas C, Manso T, Martins F, Minto L, Moreira R, Minozzo J, Antunes B, Vale A, McDaniel JR, Ippolito GC, Felicori LF.The antibody repertoire (Rep-seq) sequencing revolutionized the diversity of antigen B cell receptor studies, allowing deep and quantitative analysis to decipher the role of adaptive immunity in health and disease. Particularly, horse (Equus caballus) polyclonal antibodies have been produced and used since the century XIX to treat and prophylaxis diphtheria, tuberculosis, tetanus, pneumonia, and, more recently, COVID-19. However, our knowledge about the horse B cell receptors repertories is minimal. We present a deep horse antibody heavy chain repertoire (IGH) characterization of non-infected ...
Munday JS, Knight CG, Luff JA.Papillomaviruses (PVs) are well recognized to cause pre-neoplastic and neoplastic diseases in humans. Similarly, there is increasing evidence that PVs play a significant role in the development of pre-neoplastic and neoplastic diseases of the haired skin of dogs and cats, and the mucosa of horses. As the mechanisms by which PVs cause neoplasia are well studied in humans, it is valuable to compare the PV-induced neoplasms of humans with similar PV-associated neoplasms in the companion animal species. In the second part of this comparative review, the pre-neoplastic and neoplastic diseases thoug...
Arroyo LG, Hodgins DC, Guest B, Costa M, Ma Z, Monteiro MA.Clostridioides difficile (formerly Clostridium difficile) is associated with colitis in foals and mature horses. C. difficile exposes specific phosphorylated polysaccharides (PSs), named PS-I, PS-II and PS-III. These cell-surface PSs are potential vaccine targets, especially the hexasaccharide phosphate PS-II, that has been found in all C. difficile ribotypes examined. Since we previously identified anti-PS-II circulating antibodies in horses, we postulated that vaccinating foals with PS-II may prevent colonization by C. difficile. In this study, we aim to evaluate the IgM antibody response...
Marenzoni ML, De Waure C, Timoney PJ.Equid herpesvirus type 1 (EHV-1) infection can cause a range of disease syndromes of variable severity that can result in a lethal outcome and restriction of horse movements, especially in the case of outbreaks involving neurological disease. Vaccination is one of the tools used to control the infection. It is widely known that vaccination is not completely effective in ensuring protection against disease caused by this virus. In fact, the real efficacy of vaccination against EHV-1 related disease has not been measured and no systematic reviews exist on this topic. Objective: To perform a syst...
Kahn SK, Cohen ND, Bordin AI, Coleman MC, Heird JC, Welsh TH.The bacterium Rhodococcus equi causes pneumonia in foals that is prevalent at breeding farms worldwide. In the absence of an effective vaccine, transfusion of commercial plasma from donor horses hyperimmunised against R. equi is used by many farms to reduce the incidence of pneumonia among foals at farms where the disease is endemic. The effectiveness of hyperimmune plasma for controlling R. equi pneumonia in foals has varied considerably among reports. The purposes of this narrative review are: (1) to review early studies that provided a foundational basis for the practice of transfusion of h...
Ahmadnejad M, Jalilzadeh-Amin G, Sykes BW.Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), like phenylbutazone (PBZ), are prescribed to treat pain and inflammation in the equine. However, experimentally their use has been associated with the development of Equine Glandular Gastric Disease (EGGD). To evaluate the prophylactic effects of Glycyrrhiza glabra root extracts (GGRE) on EGGD induction following oral administration of PBZ, 12 donkeys were used. Animals were divided into three equal groups (A, B and C) in a randomized block design. A: placebo, B: PBZ (4.4 mg/kg PO q 12 h) and C: PBZ plus GGRE (17.6 mg/kg PO q 24h). Gastroscopy an...
Jiménez-Cabello L, Utrilla-Trigo S, Barreiro-Piñeiro N, Pose-Boirazian T, Martínez-Costas J, Marín-López A, Ortego J.Bluetongue virus (BTV) and African horse sickness virus (AHSV) are widespread arboviruses that cause important economic losses in the livestock and equine industries, respectively. In addition to these, another arthropod-transmitted orbivirus known as epizootic hemorrhagic disease virus (EHDV) entails a major threat as there is a conducive landscape that nurtures its emergence in non-endemic countries. To date, only vaccinations with live attenuated or inactivated vaccines permit the control of these three viral diseases, although important drawbacks, e.g., low safety profile and effectiveness...
Hunyadi L, Chigerwe M, Sundman E.SAA is a commonly used biomarker for measuring acute inflammation in equine practice, and the administration of prophylactic plasma to foals is a routine practice in large breeding farms. Despite this, limited information is available on the values of SAA in healthy or sick neonatal foals following this common procedure. A prospective study was conducted with 31 foals from a veterinary hospital in Texas in one year. Enrolled foals were part of a foaling program, where a prophylactic hyperimmunized plasma was administered 12 h after birth. Blood was collected for SAA measurements at birth and ...
Badenhorst M, Saalmüller A, Daly JM, Ertl R, Stadler M, Puff C, de le Roi M, Baumgärtner W, Engelmann M, Brandner S, Junge HK, Pratscher B, Volz A....Equine hepacivirus (EqHV) is the closest known genetic homologue of hepatitis C virus. An effective prophylactic vaccine is currently not available for either of these hepaciviruses. The equine as potential surrogate model for hepacivirus vaccine studies was investigated, while equine host responses following vaccination with EqHV E2 recombinant protein and subsequent EqHV inoculation were elucidated. Four ponies received prime and booster vaccinations (recombinant protein, adjuvant) four weeks apart (day -55 and -27). Two control ponies received adjuvant only. Ponies were inoculated with EqHV...
Jahrling PB, Geisbert TW, Geisbert JB, Swearengen JR, Bray M, Jaax NK, Huggins JW, LeDuc JW, Peters CJ.A passive immunization strategy for treating Ebola virus infections was evaluated using BALB/ c mice, strain 13 guinea pigs, and cynomolgus monkeys. Guinea pigs were completely protected by injection of hyperimmune equine IgG when treatment was initiated early but not after viremia had developed. In contrast, mice were incompletely protected even when treatment was initiated on day 0, the day of virus inoculation. In monkeys treated with one dose of IgG on day 0, onset of illness and viremia was delayed, but all treated animals died. A second dose of IgG on day 5 had no additional beneficial e...
Thompson JM, Whitmore AC, Konopka JL, Collier ML, Richmond EM, Davis NL, Staats HF, Johnston RE.Vaccination represents the most effective control measure in the fight against infectious diseases. Local mucosal immune responses are critical for protection from, and resolution of, infection by numerous mucosal pathogens. Antigen processing across mucosal surfaces is the natural route by which mucosal immunity is generated, as peripheral antigen delivery typically fails to induce mucosal immune responses. However, we demonstrate in this article that mucosal immune responses are evident at multiple mucosal surfaces after parenteral delivery of Venezuelan equine encephalitis virus replicon pa...
Hinchcliff KW, Couetil LL, Knight PK, Morley PS, Robinson NE, Sweeney CR, van Erck E.Published studies of exercise-induced pulmonary hemorrhage (EIPH), when assessed individually, often provide equivocal or conflicting results. Systematic reviews aggregate evidence from individual studies to provide a global assessment of the quality of evidence and to inform recommendations. Objective: Evaluate evidence to determine: if EIPH adversely affects the health, welfare or both of horses; if EIPH affects the athletic capacity of horses; the efficacy of prophylactic interventions for EIPH; and if furosemide affects the athletic capacity of horses. Methods: None. Methods: Systematic re...
Paillot R, Hannant D, Kydd JH, Daly JM.Equine influenza virus is a leading cause of respiratory disease in the horse. Equine influenza vaccines containing inactivated virus were first developed in the 1960s. Despite their intensive use, equine influenza outbreaks still continue to occur and therefore new strategies of vaccination are necessary to improve vaccine efficacy. Numerous methods of vaccination have been evaluated and commercialised in the horse, the most recent being the cold-adapted influenza virus and poxvirus-based vaccines. As a large animal model, the horse is also a useful species in which to evaluate the potential ...
Davidson AH, Traub-Dargatz JL, Rodeheaver RM, Ostlund EN, Pedersen DD, Moorhead RG, Stricklin JB, Dewell RD, Roach SD, Long RE, Albers SJ, Callan RJ....To compare neutralizing antibody response between horses vaccinated against West Nile virus (WNV) and horses that survived naturally occurring infection. Methods: Cross-sectional observational study. Methods: 187 horses vaccinated with a killed WNV vaccine and 37 horses with confirmed clinical WNV infection. Methods: Serum was collected from vaccinated horses prior to and 4 to 6 weeks after completion of an initial vaccination series (2 doses) and 5 to 7 months later. Serum was collected from affected horses 4 to 6 weeks after laboratory diagnosis of infection and 5 to 7 months after the first...
Issel CJ, Horohov DW, Lea DF, Adams WV, Hagius SD, McManus JM, Allison AC, Montelaro RC.We report here on a series of vaccine trials to evaluate the effectiveness of an inactivated equine infectious anemia virus (EIAV) whole-virus vaccine and of a subunit vaccine enriched in EIAV envelope glycoproteins. The inactivated vaccine protected 14 of 15 immunized ponies from infection after challenge with at least 10(5) 50% tissue culture-infective doses of the homologous prototype strain of EIAV. In contrast, it failed to prevent infection in any of 15 immunized ponies that were challenged with the heterologous PV strain. Levels of PV virus replication and the development of disease, ho...
Kydd JH, Townsend HG, Hannant D.Equine herpesvirus-1 (EHV-1) is an alphaherpesvirus which infects horses, causing respiratory and neurological disease and abortion in pregnant mares. Latency is established in trigeminal ganglia and lymphocytes. Immunity to EHV-1 lasts between 3 and 6 months. Current vaccines, many of which contain inactivated virus, have reduced the incidence of abortion storms in pregnant mares but individual animals, which may be of high commercial value, remain susceptible to infection. The development of effective vaccines which stimulate both humoral and cellular immune responses remains a priority. Uti...
Fukunaga Y, Kumanomido T, Kamada M.Getah virus is a member of the genus Alphavirus in the family Togaviridae and has been frequently isolated from mosquitoes. Seroepizootiologic studies indicate that the virus is mosquito-borne and widespread, ranging from Eurasia to southeast and far eastern Asia, the Pacific islands, and Australasia. The natural host animal of the virus was not known until the first recognized occurrence of Getah virus infection among racehorses in two training centers in Japan in 1978. Outbreaks of clinical disease due to Getah virus infection occur infrequently, and only one outbreak has been reported outsi...
Lu J, Guo Z, Pan X, Wang G, Zhang D, Li Y, Tan B, Ouyang L, Yu X.Avian influenza virus H5N1 has demonstrated considerable pandemic potential. Currently, no effective vaccines for H5N1 infection are available, so passive immunotherapy may be an alternative strategy. To investigate the possible therapeutic effect of antibody against highly pathogenic H5N1 virus on a mammal host, we prepared specific equine anti-H5N1 IgGs from horses vaccinated with inactivated H5N1 virus, and then obtained the F(ab')2 fragments by pepsin digestion of IgGs. Methods: The horses were vaccinated with inactivated H5N1 vaccine to prepare anti-H5N1 IgGs. The F(ab')2 fragments were p...
Gramiccia M.The leishmanioses are diseases caused by protozoa of the genus Leishmania, parasites infecting numerous mammal species, including humans, and transmitted by the bite of phlebotomine sand flies. They are a large group of diseases ranging over inter-tropical zones of America and Africa, and extend into temperate regions of Latin America, Europe and Asia. Pet animals are found infected with different Leishmania species but Leishmania infantum is the most widespread being dogs the main reservoir of zoonotic visceral leishmaniosis (ZVL). Dogs are very susceptible to this parasite and may suffer fro...
Ledizet M, Kar K, Foellmer HG, Wang T, Bushmich SL, Anderson JF, Fikrig E, Koski RA.West Nile (WN) virus is a flavivirus that first appeared in North America in 1999. Since then, more than 600 human deaths and 22,000 equine infections have been attributed to the virus in the United States. We expressed a truncated form of WN virus envelope (E) protein in Drosophila S2 cells. This soluble recombinant E protein was recognized by antibodies from naturally infected horses, indicating that it contains native epitopes. Mice and horses produced high-titer antibodies when immunized with recombinant E protein combined with aluminum hydroxide. Immunized mice were resistant to challenge...
Lewis MJ, Wagner B, Woof JM.Recombinant versions of the seven equine IgG subclasses were expressed in CHO cells. All assembled into intact immunoglobulins stabilised by disulphide bridges, although, reminiscent of human IgG4, a small proportion of equine IgG4 and IgG7 were held together by non-covalent bonds alone. All seven IgGs were N-glycosylated. In addition IgG3 appeared to be O-glycosylated and could bind the lectin jacalin. Staphylococcal protein A displayed weak binding for the equine IgGs in the order: IgG1>IgG3>IgG4>IgG7>IgG2=IgG5>IgG6. Streptococcal protein G bound strongly to IgG1, IgG4 and IgG7, moderately t...
Hatheway CH, Snyder JD, Seals JE, Edell TA, Lewis GE.Serum levels of equine-botulism antitoxin to toxin types A, B, and E were measured in four type-A botulism patients who had received equine-botulism antitoxin. High circulating levels capable of neutralizing in excess of 1 X 10(8), 9 X 10(7), and 6 X 10(6) 50% mouse lethal doses of toxin of types A, B, and E, respectively, were detected. There was little depletion of type-A antitoxin even though two of the patients had circulating type-A toxin before treatment. The half-life for antitoxin persistence for one patient was calculated as being 6.5, 7.6, and 5.3 days for antitoxin types A, B, and E...
Hannaman D, Dupuy LC, Ellefsen B, Schmaljohn CS.Venezuelan equine encephalitis virus (VEEV), a mosquito-borne alphavirus, causes periodic epizootics in equines and is a recognized biological defense threat for humans. There are currently no FDA-licensed vaccines against VEEV. We developed a candidate DNA vaccine expressing the E3-E2-6K-E1 genes of VEEV (pWRG/VEE) and performed a Phase 1 clinical study to assess the vaccine's safety, reactogenicity, tolerability, and immunogenicity when administered by intramuscular (IM) or intradermal (ID) electroporation (EP) using the Ichor Medical Systems TriGrid™ Delivery System. Subjects in IM-EP gro...
de la Rosa G, Olvera F, Archundia IG, Lomonte B, Alagón A, Corzo G.Antivenoms are fundamental in the therapy for snakebites. In elapid venoms, there are toxins, e.g. short-chain α-neurotoxins, which are quite abundant, highly toxic, and consequently play a major role in envenomation processes. The core problem is that such α-neurotoxins are weakly immunogenic, and many current elapid antivenoms show low reactivity towards them. We have previously developed a recombinant consensus short-chain α-neurotoxin (ScNtx) based on sequences from the most lethal elapid venoms from America, Africa, Asia, and Oceania. Here we report that an antivenom generated by immu...
Furusawa T, Iwano H, Hiyashimizu Y, Matsubara K, Higuchi H, Nagahata H, Niwa H, Katayama Y, Kinoshita Y, Hagiwara K, Iwasaki T, Tanji Y, Yokota H....Bacterial keratitis of the horse is mainly caused by staphylococci, streptococci, and pseudomonads. Of these bacteria, Pseudomonas aeruginosa sometimes causes rapid corneal corruption and, in some cases, blindness. Antimicrobial resistance can make treatment very difficult. Therefore, new strategies to control bacterial infection are required. A bacteriophage (phage) is a virus that specifically infects and kills bacteria. Since phage often can lyse antibiotic-resistant bacteria because the killing mechanism is different, we examined the use of phage to treat horse bacterial keratitis. We isol...
Bertin FR, de Laat MA.Insulin dysregulation is the hallmark of equine metabolic syndrome and has received attention because of its direct association with laminitis. In the absence of an adequate treatment for laminitis, a focus on prophylaxis is needed, making early detection of individuals at risk of developing laminitis one of the main challenges in equine endocrinology. Recent studies have shown that insulin dysregulation goes beyond tissue insulin resistance and it is now demonstrated that the equine enteroinsular axis plays a major role in insulin secretion and equine hyperinsulinaemia. In this review, we dis...
Pfaender S, Walter S, Grabski E, Todt D, Bruening J, Romero-Brey I, Gather T, Brown RJ, Hahn K, Puff C, Pfankuche VM, Hansmann F, Postel A, Becher P....Hepatitis C virus (HCV) displays a restricted host species tropism and only humans and chimpanzees are susceptible to infection. A robust immunocompetent animal model is still lacking, hampering mechanistic analysis of virus pathogenesis, immune control, and prophylactic vaccine development. The closest homolog of HCV is the equine nonprimate hepacivirus (NPHV), which shares similar features with HCV and thus represents an animal model to study hepacivirus infections in their natural hosts. We aimed to dissect equine immune responses after experimental NPHV infection and conducted challenge ex...
Sykora S, Brandt S.Squamous cell carcinoma (SCC) is a common disease that seriously impairs the health and welfare of affected horses and other equids. In humans, almost all cervical carcinomas, a high percentage of anogenital SCCs and a subset of SCCs of the head and neck are caused by high-risk human papillomavirus (hrHPV) infection. Since hrHPV-induced human cancers and equine SCC have similar cytological and histopathological features, it has been hypothesised that equine SCCs could also be induced by papillomaviruses. This review provides an overview of the current evidence for an aetiological association b...
Turner CE, Kurupati P, Wiles S, Edwards RJ, Sriskandan S.Currently there is no licensed vaccine against the human pathogen Streptococcus pyogenes. The highly conserved IL-8 cleaving S. pyogenes cell envelope proteinase SpyCEP is surface expressed and is a potential vaccine candidate. A recombinant N-terminal part of SpyCEP (CEP) was expressed and purified. AntiCEP antibodies were found to neutralize the IL-8 cleaving activity of SpyCEP. CEP-immunized mice had reduced bacterial dissemination from focal S. pyogenes intramuscular infection and intranasal infection. We also identified a functional SpyCEP-homolog protease SeCEP, expressed by the equine p...
Cywes-Bentley C, Rocha JN, Bordin AI, Vinacur M, Rehman S, Zaidi TS, Meyer M, Anthony S, Lambert M, Vlock DR, Giguère S, Cohen ND, Pier GB.Immune correlates of protection against intracellular bacterial pathogens are largely thought to be cell-mediated, although a reasonable amount of data supports a role for antibody-mediated protection. To define a role for antibody-mediated immunity against an intracellular pathogen, Rhodococcus equi, that causes granulomatous pneumonia in horse foals, we devised and tested an experimental system relying solely on antibody-mediated protection against this host-specific etiologic agent. Immunity was induced by vaccinating pregnant mares 6 and 3 weeks prior to predicted parturition with a conjug...
Martens RJ, Martens JG, Fiske RA, Hietala SK.The immunoprophylactic capacity of specific immune plasma was evaluated in pony foals infected experimentally with Rhodococcus equi. Immune plasma, produced by repeated parenteral administration of viable R. equi to adult horses, was harvested and frozen. Group I (six control foals) and Group II (six principal foals) received lactated Ringers solution and immune plasma respectively at three and five days of age. R. equi were aerosolised into a caudal lung lobe of all foals at seven days of age. Clinical signs, haematological alterations, immune responses, thoracic radiographs and technetium99m...
Mumford JA, Wilson H, Hannant D, Jessett DM.Equine influenza vaccines containing inactivated whole virus and Carbomer adjuvant stimulated higher levels and longer lasting antibody to haemagglutinin in ponies than vaccines of equivalent antigenic content containing aluminium phosphate adjuvants. Five months after the third dose of vaccine containing Carbomer adjuvant, ponies were protected against clinical disease induced by an aerosol of virulent influenza virus (A/equine/Newmarket/79, H3N8). In contrast ponies which received vaccine containing aluminium phosphate adjuvant were susceptible to infection and disease. There was an inverse ...
Ireland JL, Wylie CE, Collins SN, Verheyen KL, Newton JR.This study aimed to describe the provision of preventive health care and owner-reported disease prevalence in horses and ponies within Great Britain (GB), and to assess geographical variations in health care provision. A cross-sectional survey was conducted, using a postal questionnaire administered to a random sample of veterinary-registered owners of horses and ponies in GB (n=797). The majority of animals received regular preventive health care: 95.6% had regular hoof care; 71.3% were vaccinated for both influenza and tetanus and median time since last anthelmintic administration was 8.7 we...
Newton JR, Townsend HG, Wood JL, Sinclair R, Hannant D, Mumford JA.Field outbreaks of influenza that occurred in vaccinated Thoroughbred racehorses in Newmarket in 1995 and 1996 were investigated by nucleoprotein ELISA and serology. Investigations showed that serum levels of vaccine-induced single radial haemolysis (SRH) antibody correlated closely with protective immunity against equine influenza and were consistent with observations made in previous experimental studies using nebulised aerosol challenge. In the second part of this study, antibody levels stimulated by vaccination were investigated to examine probable protection in high risk groups, such as y...
Johns IC, Baxter K, Booler H, Hicks C, Menzies-Gow N.To describe the bacterial and fungal flora of the normal conjunctiva of horses in the UK; to determine the effect of horse age, sex, geographic location, and housing on this flora; and to determine the most appropriate antimicrobial drug(s) for prophylactic treatment of corneal ulcers. Methods: A total of 60 adult healthy horses were studied. Methods: Swabs of the conjunctiva were obtained from 60 horses housed in two locations within the UK. Specimens were cultured for aerobic bacteria and fungi, and sensitivity against six ophthalmic antimicrobials assessed. The effect of age, sex, location ...
Maxwell LK, Bentz BG, Gilliam LL, Ritchey JW, Pusterla N, Eberle R, Holbrook TC, McFarlane D, Rezabek GB, Meinkoth J, Whitfield C, Goad CL, Allen GP.OBJECTIVE To determine whether prophylactic administration of valacyclovir hydrochloride versus initiation of treatment at the onset of fever would differentially protect horses from viral replication and clinical disease attributable to equine herpesvirus type-1 (EHV-1) infection. ANIMALS 18 aged mares. PROCEDURES Horses were randomly assigned to receive an oral placebo (control), treatment at detection of fever, or prophylactic treatment (initiated 1 day prior to viral challenge) and then inoculated intranasally with a neuropathogenic strain of EHV-1. Placebo or valacyclovir was administered...
Li F, Craigo JK, Howe L, Steckbeck JD, Cook S, Issel C, Montelaro RC.Previous evaluations of inactivated whole-virus and envelope subunit vaccines to equine infectious anemia virus (EIAV) have revealed a broad spectrum of efficacy ranging from highly type-specific protection to severe enhancement of viral replication and disease in experimentally immunized equids. Among experimental animal lentivirus vaccines, immunizations with live attenuated viral strains have proven most effective, but the vaccine efficacy has been shown to be highly dependent on the nature and severity of the vaccine virus attenuation. We describe here for the first time the characterizati...
Minke JM, Siger L, Cupillard L, Powers B, Bakonyi T, Boyum S, Nowotny N, Bowen R.The emergence of lineage 2 strains of WNV in Europe as a cause of clinical disease and mortality in horses raised the question whether the existing WNV vaccines, all based on lineage 1 strains, protect against circulating lineage 2 strains of WNV. In the present paper we have determined the level of cross protection provided by the recombinant ALVAC(®)-WNV vaccine in a severe challenge model that produces clinical signs of WNV type 2 disease. Ten horses were vaccinated twice at 4 weeks interval with one dose of the ALVAC-WNV vaccine formulated at the minimum protective dose. A further 10 hors...
