Topic:Air Quality
Air quality refers to the presence and concentration of pollutants and particulates in the air that horses breathe. It encompasses a range of environmental factors, including dust, ammonia, mold spores, and other airborne contaminants commonly found in equine environments such as stables and arenas. Poor air quality can impact respiratory health in horses, leading to conditions such as recurrent airway obstruction (RAO) and inflammatory airway disease (IAD). This topic explores the sources and effects of air pollutants on equine respiratory systems and examines management practices aimed at improving air quality in equine facilities. This page compiles peer-reviewed research studies and scholarly articles that investigate the impact of air quality on horse health and performance.
Evaluation of some parameters influencing the drug delivery from a dry powder inhalation device using an in vitro model of the horse airways. The aim of this study was to determine the effect of breathing pattern, air humidity and position of the device on the delivery of an aerosol generated by a dry powder inhalation (DPI) device (Inhalator M). The in vitro inhalation study was performed using the cascade impaction method (Andersen Sampler) adapted to imitate nasal breathing. The amount of ipratropium found in the device, the artificial upper airways and the six stages of the Andersen Sampler was measured using high precision liquid chromatography. Stage 1 of the Andersen Sampler was considered to be the respirable fraction and st...
Airborne dust and aeroallergen concentrations in different sources of feed and bedding for horses. Standardized methods were used to make quantitative and qualitative assessments of respirable dust and aeroallergens in feed and bedding for horses. Concentrations of airborne dust were measured by using a Rion particle counter, and levels of major aeroallergens implicated in chronic obstructive pulmonary disease were measured by using an Andersen sampler. Laboratory conditions allowed comparison of the different sources of forage, supplements, and bedding without external influences such as ventilation, external temperature and horse activity affecting the result. Grass silages of approximate...
Effects of road transport on indices of stress in horses. Stress associated with road transport is believed to be a significant contributor to the pathogenesis of post transport respiratory disease in horses. To determine the effects of road transport on pulmonary function, pulmonary aerosol clearance rates were measured in 4 horses 24 h before, and immediately after, 24 h of road transport by delivering aerosolised 99mtechnetium-labelled diethylenetriaminepentacetate (99mTc-DTPA) to the lungs and monitoring its washout. Each horse was transported twice, once while the trailer was equipped with a leaf-spring suspension and bias-ply tyres (trailer's o...
Respiratory disease in thoroughbred horses in training: the relationships between disease and viruses, bacteria and environment. A longitudinal study of respiratory disease in racehorses was carried out to assess its relative associations with different infectious agents and to examine any role that the environmental conditions might play. The relationships between coughing, nasal discharge, pyrexia and lower respiratory tract disease were also examined to provide information for improving clinical diagnosis, particularly of disease of the lower respiratory tract. Lower airway disease was closely associated with infection with Streptococcus zooepidemicus. It was also found that equine herpesvirus seroconversions and S p...
Effects of ozone and airway inflammation on glutathione status and iron homeostasis in the lungs of horses. To investigate the effects of ozone and airway inflammation on indices of oxidant injury in horses. Methods: 5 clinically normal horses and 25 horses referred for poor performance. Methods: Blood, tracheal wash, and bronchoalveolar lavage fluid samples were collected before and after ozone exposure (n = 5) or from clinical cases (n = 25), and were analyzed for reduced glutathione (GSH), glutathione disulfide (GSSG), and free and total iron (Fe) values. A scoring system (0 to 5) was used to assess airway inflammation on the basis of clinical signs and cytologic analysis of the tracheal wash and...
A survey of exercise-induced pulmonary haemorrhage in Quebec standardbred racehorses. Sixty Standardbred horses, aged 3 to 10 years, were examined endoscopically for exercise-induced pulmonary haemorrhage (EIPH) 1 h after racing, on at least 3 occasions. Racing time, finishing position and post exercise venous lactate concentrations were also recorded. Horses positive for tracheal blood on endoscopy were classified as having either grade 1 EIPH (one or a few spots of blood in the trachea), or grade 2 (stream of blood). Air temperature, relative humidity and air pollutant levels were recorded on each examination day. Of the 60 horses, 52 (87%) were EIPH-positive on at least one ...
Survey of selected design and ventilation characteristics of racehorse stables in the Pretoria, Witwatersrand, Vereeniging area of South Africa. Stables housing more than 20 horses in training were surveyed in the Pretoria, Witwatersrand, Vereeniging area of South Africa. Most racehorses were kept in loose boxes, bedded on straw or sawdust and remained indoors while the stables were cleaned. The average floor area was 13 m2 and airspace was 55 m3 per animal. The average predicted minimum air change rate by natural convection in calm winds was 7.0 air changes per hour, which was reduced to 2.2 when the doors and shutters were closed. The survey showed that many of the stables had been built without due consideration to factors that migh...
Airborne dust and aeroallergen concentration in a horse stable under two different management systems. Airborne dust concentration (ADC) was measured in 2 different horse management systems using an Andersen cascade impactor in the box-stall, and a personal Marple cascade impactor attached to the halter to measure ADC in the breathing zone. The levels of aeroallergens implicated in chronic obstructive pulmonary disease were measured by radioallergosorbent-inhibition immunoassay. A conventional management system (System C) utilising hay feed and straw bedding, and a recommended environment (System R) utilising wood shaving bedding and a complete pelleted diet were studied. In the stall, total an...
[Riding arenas and different riding track surfaces in relation to the airway contamination in horses. Laboratory studies on riding surfaces]. 29 samples of commonly used surfaces were tested for their water characteristics (litre weight, water capacity, water binding, water evaporation) and their contribution to airborne fungal spores (dust formation, dust setting). The results are discussed in comparison to the literature with regard to the environment. The results are: 1. Any surface--no matter of what material--eventually causes air pollution with fungal spores and dust. 2. Correct watering prevents air pollution by any surface. 3. Artificial products have no advantage over natural materials in the parameters tested. 4. The quest...
[Studies in riding arenas and on different riding path surfaces with respect to respiratory tract contamination in horses. Air hygiene studies in riding arenas]. Using the direct sedimentation method, the air pollution with fungal spores was measured in indoor riding arenas and compared to horse stables, outside riding arenas and covered sport courts. Depending on the location of indoor arenas and stables, the presence of "dust-nests", the number of horses ridden, and the moisture of the tread layer, an air pollution was measured which was equivalent to that in stables except at times of feeding and straw-giving. Outside and in sport arenas a low air pollution was found. Recommendations are given, regarding optimum air hygiene especially for horses wit...
Hazards in confinement housing–gases and dusts in confined animal houses for swine, poultry, horses and humans. Indoor atmospheres in swine or poultry confinement buildings, horse stalls or human dwellings contain gases, dusts and endotoxin in concentrations significantly in excess of those in outdoor environments. Although concentrations of such constituents differ appreciably between species, many of such differences may be related to differences in indoor mass loading and ventilation, or to the homogeneity of such ventilation. The high protein content of these indoor dust particles suggest they are of animal origin. Their ability to form bacterial colonies and to form or bind endotoxin suggest that t...
[The dust and microbial content in a horse stable during the use of a dust-binding agent]. Dust in horse barns is assumed to contribute to pulmonary disease, it is attempted to reduce the airborne dust by soaking or sprinkling the hay before feeding. Both means cause considerable efforts and increase the relative humidity of the air. This is why a commercial dust-binding agent (Revesto pur) was used in a pilot investigation which was carried out during 2 weeks - one week for control and one week using the agent - in a private horse barn where three horses were regularly stable. The airborne dust was measured by a continuously working instrument. Once a day (7.00 a.m.) the number of ...
Effect of water vapor-saturated air therapy on bronchoalveolar lavage and tracheal mucus transport rate in clinically normal horses. Water vapor-saturated air was delivered to 12 healthy, housed horses for 2 hours daily for 5 days. Treatment had no effect on tracheal mucus transport rate, bronchoalveolar lavage total and differential cell counts, blood cell counts, or plasma fibrinogen concentration.
The relationship of air hygiene in stables to lower airway disease and pharyngeal lymphoid hyperplasia in two groups of Thoroughbred horses. The relationship between air hygiene within two types of identically managed horse housing and the incidence of covert respiratory disease (as revealed by endoscopic examination) of their inhabitants was assessed. The horses were all under the supervision of the same trainer. In one yard the design ensured the boxes were well ventilated in still air conditions. In the other yard the boxes were insulated and there was little provision for natural ventilation in still air conditions. There was heavy fungal and actinomycete contamination of wood shavings in the heavily insulated, poorly ventilate...
Survey of the designs of racehorse stables in the south west of England. The design of 96 racehorse stables in the south west of England were surveyed. The 'typical' racehorse is kept in a loose box, bedded on straw and remains indoors while the stable is cleaned. It is given a floor area of 12 m2 and shares its airspace of 39 m3 with seven other horses. Overall, the predicted minimum rate of air change by natural convection in calm winds is 6.6 air changes/h but this is reduced to 2.2 if the top door of the stable is closed. On balance, racehorse stables in use today are based on designs which are worse overall than the best available in the 19th century.
Technique for assessing respiratory health hazards from hay and other source materials. This paper describes and compares three techniques of categorisation of hay, straw and other feeds and beddings collected from stables. A hand-held sampler was used to categorise samples according to the presence of plant material, fungal spores and dust mites. An Andersen sampler was used to categorise samples according to the thermotolerances of fungi and actinomycetes. An aerodynamic particle sizer was used to categorise samples according to respirable particle release rates. The highest burden of respirable particles was associated with the presence of thermophilic and thermotolerant actin...
Air hygiene in stables. 1: Effects of stable design, ventilation and management on the concentration of respirable dust. The concentration of fungal spores, the main constituents of respirable dust in stables, is determined by rates of release from fodder and bedding and rate of clearance, principally by ventilation. This paper outlines the principles that govern the application of natural ventilation to the control of air hygiene in barns and individual boxes for horses. When release rates are low, ventilation rates over four air changes per hour are satisfactory. Ventilation was satisfactory in individual boxes but usually unsatisfactory in barns and specific recommendations are made for improvement. Prelimina...
A review of environmental and host factors in relation to equine respiratory disease. This paper reviews the environmental and host factors which interact to affect the incidence and severity of episodes of respiratory disease in stabled horses. The folly of accepting housing criteria and management practices for the horse, based on direct extrapolations from intensive housing of meat producing animals, is discussed. The factors which affect air hygiene and physical environment of stables are considered in terms of short-term athletic performance and long-term welfare.
Chronic obstructive pulmonary disease in the horse. 2: Therapy. The therapy of equine chronic obstructive pulmonary disease (COPD) essentially entails minimising the horse's exposure to the aetiological antigens which are predominantly thermophilic actinomycetes and moulds occurring in hay and straw. This can be achieved, for example, by keeping affected horses permanently out of doors, or when stabled, using shredded paper, wood shavings or peat moss as bedding and feeding a complete cubed diet. There should be no supplementary hay feeding apart from dust-free vacuum-packed hay. Applying such measures generally allows horses to become asymptomatic in seve...
Ventilation and environment in relation to equine respiratory disease. The physiological requirements of the horse appear to be reasonably well established and should be adequately provided by ventilation based on straightforward principles, relying largely on natural air flow. On the other hand, there are few objective values for ventilation required to promote good health or alleviate equine respiratory disease. In the absence of such knowledge it is only possible to rely on a logical application of sound principles and experience. Both indicate the satisfactory nature of ventilation by stack effect, aspiration and perflation. Buildings should be well insulated...
Dust levels in a riding stable. Over a period of 4 months, in winter, the mean concentration of airborne particles in the ambient air of a riding stable was 0.41 mg/m3. This value was significantly higher than that found outdoors (0.04 mg/m3). During the day, levels of airborne particles were highest when stalls were cleaned and soiled bedding from the previous night replenished, and lowest when all stable activities had ceased. Fine particles, capable of entering the pulmonary alveoli, constituted 30 to 40 per cent of the total mass concentration of airborne particles.
Chronic obstructive pulmonary disease (COPD): factors influencing the occurrence. Breed, age, weight, type of work performed, seasonal onset, poor ventilation and exposure to moulds in the habitat were investigated in relation to the occurrence of chronic obstructive pulmonary disease (COPD). COPD was most commonly detected in showjumping and hacking horses. The older a horse, the more likely it was to become affected although most were 6 to 10 years of age. Of the horses in this sample of the population, which was not a random one, thoroughbred horses were affected least and ponies most often. The high incidence in ponies was related to their more frequent exposure to poor...
Recent developments in air transportation of farm animals and horses. This paper deals with some recent developments in the air transportation of cattle, sheep, pigs and horses and comments on the factors involved which influence the results.
[Various indices of microclimate in the newly built and re-adapted stables for race horses]. A study was performed to examine microclimate in 14 stables belonging to 10 horsemen's teams and clubs; five of these houses were new-built. In five race-horse stables housing 16 horses each, on an average, where the optimum air temperature ranged from 10 degrees C to 12 degrees C, measurements and examinations were performed in the winter period and the following results were obtained: space per 1 horse housed 42.9 plus or minus 8.7 m-3, relative air humidity 74.3 plus or minus 3.8%, CO2 concentration 0.175 plus or minus 0.027%, NH3 concentration 0.00135 plus or minus 0.00044%. A large majori...