Topic:Allergies
Allergies in horses are immune-mediated responses to environmental antigens, such as pollen, dust, mold, food, or insect bites, that result in hypersensitivity reactions. These reactions can manifest as respiratory issues, skin conditions, or gastrointestinal disturbances, impacting the horse's overall health and performance. Common allergic conditions in horses include recurrent airway obstruction (RAO), urticaria, and insect bite hypersensitivity. Understanding the underlying mechanisms of equine allergies is crucial for developing effective management and treatment strategies. This page compiles peer-reviewed research studies and scholarly articles that explore the pathophysiology, diagnosis, and management of allergies in horses, as well as their impact on equine welfare and performance.
Active vaccination against interleukin-5 as long-term treatment for insect-bite hypersensitivity in horses. Insect-bite hypersensitivity (IBH) in horses is a chronic allergic dermatitis caused by insect bites. Horses suffer from pruritic skin lesions, caused by type-I/type-IV allergic reactions accompanied by prominent eosinophil infiltration into the skin. Interleukin-5 (IL-5) is the key cytokine for eosinophils and we have previously shown that targeting IL-5 by vaccination reduces disease symptoms in horses. Here, we analyzed the potential for long-term therapy by assessing a second follow-up year of the previously published study. The vaccine consisted of equine IL-5 (eIL-5) covalently linked to...
The influence of hay steaming on clinical signs and airway immune response in severe asthmatic horses. Avoidance of antigenic stimuli was found to significantly reverse airway obstruction of horses with severe equine asthma (sEA). To date, no published study investigated the influence of steaming hay on lower airway condition of sEA-affected horses. The objectives were to determine the clinical, cytological and cytokine respiratory responses of both sEA and control (CTL) horses experimentally exposed to steamed or dry hay. Results: A cohort of 6 sEA horses and 6 CTL horses was involved in this field study. On day 0, both groups were fed with steamed hay for 5 consecutive days, followed by a was...
A prospective study on insect bite hypersensitivity in horses exported from Iceland into Switzerland. Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis caused by bites of Culicoides spp., which occurs frequently in horses imported from Iceland to continental Europe. IBH does not occur in Iceland because Culicoides species that bite horses are not present. However, Simulium vittatum (S. vittatum) are found in Iceland. In Europe, blood basophils from IBH-affected horses release significantly more sulfidoleukotrienes (sLT) than those from healthy controls after in vitro stimulation with Culicoides nubeculosus (C. nubeculosus) and S. vittatum. Aims of the study were: (I) using the s...
Companion animals and human health: benefits, challenges, and the road ahead for human-animal interaction. There is ample evidence that human-animal interaction (HAI) is associated with health. Studies encompass three general categories: those that compare companion animal owners with individuals who do not own companion animals, those examining brief, 'one-off' contacts with animals, and those that review animal-assisted interventions. The health benefits demonstrated typically include reductions in depression and loneliness, while enhancing social interaction or social skills, and decreasing anxiety and arousal. Other health benefits associated with companion animals include the promotion of exer...
Long-term management of horses with atopic dermatitis in southeastern England: a retrospective questionnaire study of owners’ perceptions. Allergic pruritus and urticaria in the horse are challenging for veterinarians and owners; little is known about their long-term management. Objective: To summarize intradermal allergen test results (IDT), and to assess owners' perceptions of skin disease and the effects of medical treatment and management changes in their atopic horses over time. Methods: Eighty two horses with atopic dermatitis in southeastern England between 2006 and 2011. Methods: The IDT results were reviewed retrospectively. Owners completed telephone questionnaires on skin changes, medication, effect of allergen-specifi...
Copy number variations in Friesian horses and genetic risk factors for insect bite hypersensitivity. Many common and relevant diseases affecting equine welfare have yet to be tested regarding structural variants such as copy number variations (CNVs). CNVs make up a substantial proportion of total genetic variability in populations of many species, resulting in more sequence differences between individuals than SNPs. Associations between CNVs and disease phenotypes have been established in several species, but equine CNV studies have been limited. Aim of this study was to identify CNVs and to perform a genome-wide association (GWA) study in Friesian horses to identify genomic loci associated w...
Effect of antigen challenge on dynamics of CD62P and CD41/61 expression on platelets in horses with recurrent airway obstruction (RAO). Recurrent airway obstruction (RAO), also known as heaves, is an allergic respiratory condition that develops in horses following an exposure to aeroallergens in hay and straw. This is manifested by airway hyperreactivity, inflammation, bronchoconstriction, as well as a leukocyte and platelet infiltration into the airways. Platelet activation and an increase in circulating platelet-leukocyte aggregates may lead to airway remodeling. The aim of this study was to explore the effect of seven-day antigen challenge on dynamics of platelet indices and CD41/61 and CD62 P expression on platelets in h...
Allergen immunotherapy in people, dogs, cats and horses – differences, similarities and research needs. In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a pr...
Barley produced Culicoides allergens are suitable for monitoring the immune response of horses immunized with E. coli expressed allergens. Insect bite hypersensitivity is an allergic dermatitis of horses caused by bites of Culicoides midges. Sufficient amount of pure, endotoxin-free allergens is a prerequisite for development and monitoring of preventive and therapeutic allergen immunotherapy. Aims of the study were to compare the Culicoides nubeculosus (Cul n) allergens Cul n 3 and Cul n 4, produced in transgenic barley grains with the corresponding E. coli or insect cells expressed proteins for measuring antibody and cytokine responses. Allergen-specific IgG responses were measured by ELISA in sera from twelve horses not expose...
Treating insect-bite hypersensitivity in horses with active vaccination against IL-5. Insect-bite hypersensitivity is the most common allergic dermatitis in horses. Excoriated skin lesions are typical symptoms of this seasonal and refractory chronic disease. On a cellular level, the skin lesions are characterized by massive eosinophil infiltration caused by an underlying allergic response. To target these cells and treat disease, we developed a therapeutic vaccine against equine IL-5 (eIL-5), the master regulator of eosinophils. The vaccine consisted of eIL-5 covalently linked to a virus-like particle derived from cucumber mosaic virus containing the tetanus toxoid universal T-...
Comparison of serum concentrations of environmental allergen-specific IgE in atopic and healthy (nonatopic) horses. Allergic responses in humans, horses and other species are mediated by immunoglobulin E (IgE) antibodies. Serum testing to detect allergen-specific IgE antibodies has been developed for dogs, cats and horses; this allows for the identification of allergens and determination of appropriate allergen- specific immunotherapies. This study compared serum allergen-specific IgE concentrations in atopic and healthy horses. The study was performed on Malopolski breed atopic (n=21) and nonatopic (n=21) clinically healthy horses. Allergen-specific IgE serum concentrations were measured in summer seasons ...
Molecular allergen profiling in horses by microarray reveals Fag e 2 from buckwheat as a frequent sensitizer. Companion animals are also affected by IgE-mediated allergies, but the eliciting molecules are largely unknown. We aimed at refining an allergen microarray to explore sensitization in horses and compare it to the human IgE reactivity profiles. Methods: Custom-designed allergen microarray was produced on the basis of the ImmunoCAP ISAC technology containing 131 allergens. Sera from 51 horses derived from Europe or Japan were tested for specific IgE reactivity. The included horse patients were diagnosed for eczema due to insect bite hypersensitivity, chronic coughing, recurrent airway obstructio...
Effect of ionization, bedding, and feeding on air quality in a horse stable. Organic dust is associated with Equine asthma. Ionization should reduce airborne dust levels. Objective: To determine the effect of ionization of air, type of bedding, and feed on the levels of airborne dust, endotoxin, and fungal colonies in horse stables. Methods: 24 healthy University-owned horses occupied the stables. Methods: A randomized controlled cross-over study. Four units with 6 stables were equipped with an ionization installation (25 VA, 5000 Volt Direct Current). Horses were kept either on wood shavings and fed haylage (2 units), or on straw and fed dry hay (2 units). Measurement...
Modeling asthma: Pitfalls, promises, and the road ahead. Asthma is a chronic, heterogeneous, and recurring inflammatory disease of the lower airways, with exacerbations that feature airway inflammation and bronchial hyperresponsiveness. Asthma has been modeled extensively via disease induction in both wild-type and genetically manipulated laboratory mice (Mus musculus). Antigen sensitization and challenge strategies have reproduced numerous important features of airway inflammation characteristic of human asthma, notably the critical roles of type 2 T helper cell cytokines. Recent models of disease induction have advanced to include physiologic aero...
A Pilot Qualitative Investigation of Stakeholders’ Experiences and Opinions of Equine Insect Bite Hypersensitivity in England. Equine insect bite hypersensitivity (IBH), commonly known as sweet itch or summer eczema, is a frustrating recurrent skin disease in the equine industry involving an immune reaction to the bites of spp. midges. To investigate the impact of IBH in the field, an exploratory pilot study was conducted with equine stakeholders in one region of central England. Nine semi-structured, face-to-face interviews were conducted with horse owners and an equine veterinarian. The aim was to gain an understanding of experiences with IBH, and to gauge opinions on the value of the various management strategies ...
A comparison of nanoparticullate CpG immunotherapy with and without allergens in spontaneously equine asthma-affected horses, an animal model. New therapeutic strategies to modulate the immune response of human and equine allergic asthma are still under extensive investigation. Immunomodulating agents stimulating T-regulatory cells offer new treatment options beyond conventional symptomatic treatment or specific immunotherapy for human and equine allergic airway diseases, with the goal of a homoeostatic T-helper cell balance. The aim of this study was to evaluate the effects of a nebulized gelatin nanoparticle-CpG formulation (CpG-GNP) with and without specific allergens for the treatment of spontaneous allergic equine asthma as a mo...
Longitudinal analysis of allergen-specific IgE and IgG subclasses as potential predictors of insect bite hypersensitivity following first exposure to Culicoides in Icelandic horses. Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland because of the absence of Culicoides, but the prevalence is high in horses imported from Iceland to environments where Culicoides are present. Objective: Test, in a longitudinal study before and after Culicoides exposure, whether a primary sensitizing Culicoides allergen can be identified and if an increase of allergen-specific immunoglobulin (Ig)E or IgG subclasses precedes clinical signs of IBH. Methods: Thirty two horses imported from Iceland to Europe; 16 ...
Ultrasensitive and rapid immuno-detection of human IgE anti-therapeutic horse sera using an electrochemical immunosensor. Antivenom allergy disease mediated by patient IgE is an important public health care concern. To improve detection of hypersensitive individuals prior to passive antibody therapy, an amperometric immunosensor was developed to detect reactive human IgE. Whole horse IgG3 (hoIgG3) was immobilized onto the surface of carbon or gold screen-printed electrodes through a cross-linking solution of glutaraldehyde on a chitosan film. Sera from persons with a known allergic response to hoIgG3 or non-allergic individuals was applied to the sensor. Bound human IgE (humIgE) was detected by an anti-humIgE ant...
Development of an elisa for the diagnosis of reactive IgE antibodies anti-therapeutic horse sera. Hypersensitive diseases that involve IgE reactivity are important concern of public, especially those encompassing the potential pathogenesis from the administration of horse serum-based therapeutics such as antivenoms. A method for the definitive diagnosis of reactive IgE is important for identifying allergic patients to control severe collateral effects during planned and emergency application of immunotherapies when the allergy source cannot be avoided for treatment. To date, no tests have been developed to accompany the wide range of antivenoms produced from horse sera. The aim of this was...
Determination of irritant threshold concentrations of multiple tree, grass, weed and mould allergens for intradermal testing of horses residing in the southern USA. Appropriate allergen threshold concentrations (TCs) for intradermal testing (IDT) have not been established in horses for many pollen and mould allergens. Objective: To determine the TCs in non-allergic horses and describe the frequency of late phase reactions for 26 allergens, including trees, grasses, weeds and moulds in horses residing in the southern Unites States. Methods: Twenty four clinically normal horses in the southern United States. Methods: Threshold concentrations for different allergens were determined using IDT subjective measurements at 30 minutes. Delayed reactions were evalu...
Tolerance Induction of Horse Allergy by Horse Contact with Curly Horses. A horse allergic rider completed 60 riding lessons on Curly Horses within six months. This rider has become clinically tolerant to normal horse breeds within this time. This case may indicate that riding and brushing ABCR Curly Horses after 60 riding hours facilitates tolerance induction. Our data indicate that this could be a valid alternative to the common recommendation to strictly avoid horse riding. Eine pferdeallergische Reiterin erhielt 60 Reitstunden auf „Curly Horses“ innerhalb von 6 Monaten. Die Reiterin tolerierte die Allergenexposition mit Pferden anderer Rassen innerhalb diese...
Modulatory role of regulatory T cells in a murine model of severe equine asthma. It is accepted that T regulatory cells (Treg) control different types of immune responses. In connection with this role, we have recently described an important increase in CD4+, CD25, Foxp3+ lymphocytes in the airway system of horses coursing with an exacerbation of severe equine asthma (EA). To explore the potential role of this population in the resolution of EA inflammation, we used a murine experimental model in which airway neutrophilic inflammation, which is similar to that observed in EA, is induced in mice by continual exposure to Aspergillus fumigatus contaminated hay. This model has...
Genetic parameters of insect bite hypersensitivity in the Old Grey Kladruber horse. The objective of this study was to assess the genetic parameters of insect bite hypersensitivity (IBH) in the Old Grey Kladruber horse, an original Czech warmblood horse breed. Insect bite hypersensitivity is a recurrent allergic skin disease affecting horses worldwide. Its etiology is multifactorial. The defect is genetically controlled, and the starting impulse is a bite by midges of the spp. and less frequently spp. Knowledge about the associated genes is limited. Horses were kept by the National Stud in Kladruby (1,146 measurements) and by 10 private breeders (63 measurements). The horses ...
Evaluation of serum cytokine levels in recurrent airway obstruction. Recurrent airway obstruction (RAO) represents a serious health problem and is traditionally classified as an allergic disease, where contact with an antigen can induce clinical airway inflammation, bronchial hyper-responsiveness and reversible airway obstruction. Previous studies have demonstrated the presence of the Th2 response in the lungs of human patients with asthma and horses with heaves. These cells are involved in the production of cytokines which regulate the synthesis of immunoglobulins. 40 horses were evaluated: 30 horses with RAO and 10 healthy animals. The expression levels of in...
Allergenicity of milk of different animal species in relation to human milk. Protein content in cow milk (with over 20 proteins, and peptides may also occur as a result of enzymatic hydrolysis) ranges from 2.5% to 4.2% and is about 1.5-2 times higher than in human milk. Its most important allergens are considered to be β-lactoglobulin (absent in human milk) and αs1-casein. The most similar in composition to human milk is horse and donkey milk. It contains considerably more whey proteins (35-50%) than cow milk (about 20%), and the concentration of the most allergenic casein fraction αs1 is 1.5-2.5 g/l. In comparison, the content of αs1-casein in cow milk is about 10...
Oral administration of transgenic barley expressing a Culicoides allergen induces specific antibody response. Insect bite hypersensitivity is an immunoglobulin (Ig)E-mediated dermatitis of horses initiated by bites of midges of the genus Culicoides. Culicoides spp. are not indigenous to Iceland and the prevalence of insect bite hypersensitivity is much higher in horses born in Iceland and exported as compared to Icelandic horses born in a Culicoides rich environment. Immunotherapy is therefore needed. Objective: The aim of the study was to express an allergen from Culicoides in barley grain and investigate whether an immune response could be obtained in healthy Icelandic horses by oral treatment with ...
In vitro effects of the toll-like receptor agonists monophosphoryl lipid A and CpG-rich oligonucleotides on cytokine production by equine cells. Insect bite hypersensitivity (IBH) is an equine allergic dermatitis to Culicoides spp. antigens. Attempts at using allergen-specific immunotherapy (AIT) as a treatment for IBH have so far proven unsuccessful. Toll-like receptor (TLR) agonists can promote a shift in the immune response from the allergy-promoting T helper cell 2 (Th2) response towards a Th1 and/or regulatory response. The aim of this study was to evaluate two immunomodulatory TLR agonists in vitro as potential vaccine adjuvants for a more efficacious AIT in IBH. Peripheral blood mononuclear cells (PBMCs) from healthy and IBH-aff...