Danger from airborne fungi in the stables shown in the study

photo from photography Shauna Lee

The potential contribution of pollutants in settled air to airway problems in horses and humans has been highlighted in a study just published.

Aerosol exposure in horse stables and its health effects has recently become of particular interest to researchers.

The increased frequency in horses of recurrent airway disease, also known as acute equine asthma or acute asthma, raises questions about the most likely causative factors and ways to reduce risk.

Researchers in Poland sampled and analyzed air at two stables in Poland to determine levels of particulate matter and concentrations of airborne fungal aerosols. The main impetus for conducting the study was the frequent episodes of airway problems among horses in the stables, followed by the deaths of two horses.

The three most common types of fungi have been identified And alias for himselfAnd the Aspergillus penicillium And the black epic All of them are hypersensitive and are likely to be involved in the development of severe asthma in horses.

“Spores of the fungi detected can penetrate deeply into the respiratory tract,” Anna Lennart-Browe and her fellow researchers reported in the journal. applied Sciences.

“This study indicates that assays of particulate matter and fungal aerosol concentrations, along with assessment of species composition, should be performed regularly in horse stables.”

The study team, together with the University of Agriculture in Krakow, noted that a large number of people around the world are involved in the horse industry. There are over six million recreational riders in the European Union, representing about 2% of the region’s population.

Many people spend a lot of time in stables, either taking care of or training horses, or as enthusiasts who devote their spare time to horse riding. As a result, both people and horses in stables are exposed to airborne pollutants.

Airborne pollutants associated with the environments in which animals live include toxic gases, such as ammonia or hydrogen sulfide; inorganic particles, such as soil dust; non-viable organic particles, such as feed or fecal droplets; As well as viable particles such as bacteria and fungi, their fragments and toxins. They are all referred to as bioaerosols.

Inflammatory airway diseases are the most common inflammatory disease in horses, affecting up to 20% of adult horses in the Northern Hemisphere. Horses usually exhibit many characteristic symptoms, including coughing, nasal discharge, increased breathing effort at rest, and exercise intolerance.

Concerns about indoor bioaerosol levels and exposure have increased in recent years, in large part due to the recognition that exposure to them is associated with a wide range of adverse health effects.

In their study, the researchers examined air samples from one stable in Krakow and another in Tarnow, looking at three sizes of airborne particles (PM).10evening2.5and PM1). They also performed culture-based assessments of fungal bioaerosol concentrations, and then used molecular technology to identify them.

Samples were collected inside and outside the stables.

The authors found that particulate concentrations differed significantly between the horse stables examined and at different times of the day. It was much higher in Tarnow stable than in Krakow.

In the Krakow stable, the lowest particle levels were observed during midday, when there was no activity, while in the Tarnow stable, the lowest particle levels were observed in the early morning.

The highest concentrations of all parts of the fungal aerosol were observed in the Krakow stable during horse feeding. The total fungal aerosol concentration during feeding was 82 times higher than that recorded during the midday quiescent period, while the respirable fraction was 68 times higher during feeding than during the midday period.

In the Tarnów stable, the highest concentrations of all parts of the fungal aerosol were observed during sedentary activities, such as cleaning. The lowest concentrations were in the early morning. The highest fungal aerosol concentrations were five times higher than the lowest values ​​from early morning.

When discussing their findings, the researchers said that the concentration of the fungal aerosol changed significantly depending on the time of day and activities performed indoors in both stables.

“The highest concentrations of all fractions of aerosols were observed in the Krakow stable during feeding. In the Tarnów stable, the highest concentrations of all fractions of aerosols were observed during daily activities performed indoors, and similarly for particulate matter.

“Our study showed that daily activities performed in horse stables, such as feeding or grooming horses, contributed significantly to increased levels of particulate and fungal components of the bioaerosol.”

The respirable fractions of the fungal aerosols in many cases fluctuated around 80% of the total fraction, indicating potential health risks to exposed people and animals.

Among the two stables examined, the Tarnów stable was distinguished by higher particulate concentrations, while the gross and respirable fractions of fungal aerosols were higher in the Kraków stable.

The observed fungal aerosol concentrations from the stables were compared with the Polish ZECB (Expert Group on Biological Agents) proposal on airborne microorganism concentrations in animal room treatment.

Concentrations of both the total fraction and the respirable fraction of the fungal aerosol exceeded the suggested values ​​only once—that is, during horse feeding and only in the Krakow stable.

However, the most widespread species, And alias for himselfis an important type of allergen, producing large numbers of small, easily disseminated spores that can penetrate deeply into the respiratory tract.

In addition, the second and third most prevalent types, Aspergillus penicillium And the black epicThey are often described as causative agents of allergic reactions and a possible contributor to respiratory disease in horses.

In fact, of the 10 most abundant fungal genera observed in the Krakow stable, five are listed as the most common allergens

“With this in mind, air quality measurements, including assessment of particulate matter and fungal aerosol concentrations, along with identification of the most prevalent fungal species, are highly recommended in horse stables where there are cases of allergic reactions, respiratory disease in workers, or obstructive cases. Frequent airway between horses.

The study team consisted of Lennart-Borough, Anna Bajor, Marek Tishner, Claudia Kollek, and Julia Kabasinska.

Lenart-Boroń, A.; Bajor, A.; Tishner, M.; Kulik, K.; Kabacińska, J. Particulate matter and fungal aerosol concentrations in horse stables as possible causal factors in recurrent airway diseases in horses, human asthma and allergies. Science application. 2022, 12, 9375.

The study published under CC licensecan be read over here.