Nav: Home

Fungus a possible precursor of severe respiratory diseases in pigs

July 20, 2016

Respiratory diseases in pigs typically involve multiple infections from different pathogens. Some pathogens play a greater role than others in the progression of the disease. The fungus Pneumocystis carinii is a relatively common cause of pneumonia in Austrian pigs, but its role has so far remained largely unexplored. Pneumocystis is considered to be less dangerous than other pathogens, as it probably requires other underlying conditions to sufficiently weaken the immune defence of the animals first.

A research team from Vetmeduni Vienna has now demonstrated the susceptibility of piglets to the fungus as well as its relation with other pathogens in the progression of the disease. Their research has shown that the fungus plays a more important role in pneumonia than had previously been assumed. Detecting pneumocystis in a medical examination requires a lung lavage, which, however, is less stressful to the animals than other sampling methods.

Pneumocystis in sick piglets of all age groups

The researchers began by testing stored tissue samples of sick piglets for the presence of the fungus and other pathogens. Pneumocystis was detected in piglets of all ages. In suckling piglets, only the fungus was detected in lung tissue. The older the piglets, the more bacteria could be detected. Pneumocystis itself was no longer as prevalent as in the suckling piglets. The fungus, however, appeared to have proliferated before the bacterial pathogens.

This suggests that the fungus plays a role as a "door opener" for secondary infections. "First the fungus spreads along the alveolar walls. From there it proliferates and fills the alveolar spaces. As a result, the lung tissue receives insufficient oxygen and bacteria can reproduce better in the damaged tissue," explains Christiane Weissenbacher-Lang of the Institute for Pathology and Forensic Veterinary Medicine, describing the possible progression of the infection.

Fungus detectable in living pigs only with lung lavage

The progress of the infection can be easily demonstrated in the laboratory using lung biopsies. In living pigs, however, this type of sampling is difficult and not suitable for routine testing. The team around Weissenbacher-Lang therefore tested whether oral fluid samples and lung lavages from sick pigs could be suitable for a diagnosis. Lung lavages are less stressful and easier to perform than biopsies. They also offer the advantage that material is collected from the entire lung.

Role of Pneumocystis carinii likely underestimated

The researchers demonstrated that it was possible to clearly diagnose even a weak infection with the material from a lavage. The presence of fungal DNA can be specifically demonstrated using molecular methods such as real-time PCR. The test was designed to detect the strains typically found in pigs. Oral fluid samples were determined to be not suitable for diagnosing mild or moderate infections. Sampling through lung lavages therefore appears to be the best method for diagnosing the fungus in routine testing among living pigs.

Weissenbacher-Lang intends to conduct further tests to show that pneumocystis pneumonia can play a role as an additional factor in co-infections with other respiratory pathogens. If this were the case, it would be necessary to respond in time. The high susceptibility demonstrated among the tested pigs shows that pneumocystis should not be underestimated, even if the fungus itself has so far been categorized as a low risk for pigs.

Lung lavage an option for routine testing

Respiratory diseases in pigs are an economic risk for farms. The potential loss is great. Keeping the animals in pens therefore requires high quality standards for the ventilation alone. If a pathogen still manages to manifest itself in the pen, veterinary measures must be taken in time to keep the majority of the herd healthy. Lung lavages are a suitable method for regular testing of the herd.

Biopsies time-consuming and potentially harmful to the animals

Biopsies require the animals to be anaesthetized and samples to be collected under ultrasound guidance. The procedure is time-consuming, stressful for the animal and involves potential health risks. Lung lavages are much less stressful and take less time to perform. The pigs are anaesthetized only briefly. The lavage itself takes only a few minutes. Lavages are a routine method in human medicine. Veterinarians are also familiar with this procedure and the method could therefore be applied in the pen without any major adaptations necessary for testing.
-end-
Service:

The article "Establishment of a quantitative real-time PCR for the detection of Pneumocystis carinii f. sp. suis in bronchoalveolar lavage samples from pigs" by Christiane Weissenbacher-Lang, Nora Nedorost, Christian Knecht, Isabel Henning-Pauka and Herbert Weissenböck was published in the Journal of Veterinary Diagnostic Investigation. http://vdi.sagepub.com/content/28/3/257.long

The article "Association between Pneumocystis spp. and co-infections with Bordetella bronchiseptica, Mycoplasma hyopneumoniae and Pasteurella multocida in Austrian pigs with pneumonia" by B. Kureljusic, C. Weissenbacher-Lang, N. Nedorost, D. Stixenberger and H. Weissenböck was published in The Veterinary Journal.http://www.sciencedirect.com/science/article/pii/S1090023315004748

About the University of Veterinary Medicine, Vienna

The University of Veterinary Medicine, Vienna in Austria is one of the leading academic and research institutions in the field of Veterinary Sciences in Europe. About 1,300 employees and 2,300 students work on the campus in the north of Vienna which also houses five university clinics and various research sites. Outside of Vienna the university operates Teaching and Research Farms. http://www.vetmeduni.ac.at

Scientific Contact:

Christiane Weissenbacher-Lang
Institute of Pathology and Forensic Veterinary Medicine
University of Veterinary Medicine Vienna (Vetmeduni Vienna)
T 43-1-25077-2413
christiane.weissenbacher-lang@vetmeduni.ac.at

University of Veterinary Medicine -- Vienna

Related Pneumonia Articles:

Osteoporosis treatment may also protect against pneumonia
A recent study published in the Journal of Bone and Mineral Research found that nitrogen-containing bisphosphonates (N-BPs) such as alendronate, which are widely used to treat postmenopausal osteoporosis, are linked with lower risks of pneumonia and of dying from pneumonia.
Elderly patients with pneumonia twice as likely to die as those with broken hips, yet underestimate the danger of pneumonia
Elderly patients who are hospitalised with pneumonia are twice as likely to die as those hospitalised with hip fractures -- yet many elderly people fail to accurately assess their risk of pneumonia, concludes research due to be presented at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID).
Pneumonia recovery reprograms immune cells of the lung
Researchers have determined that after lungs recover from infection, alveolar macrophages (immune cells that live in the lungs and help protect the lungs against infection) are different in multiple ways and those differences persist indefinitely.
Skin and mucous membrane lesions as complication of pneumonia
Painful inflammatory lesions of the skin and mucous membranes may occur in children who develop bacterial pneumonia.
Vaccine reduces likelihood of severe pneumonia
A new study has found severe pneumonia decreases by 35 per cent in children who receive a vaccine against a pneumonia-causing bacteria.
Bacteria in pneumonia attack using bleaching agent
Research shows that bacteria use hydrogen peroxide to weaken the immune system and cause pneumonia.
Many kids with pneumonia get unnecessary antibiotics, chest X-rays
Preschool children with community-acquired pneumonia often receive unnecessary tests and treatment at outpatient clinics and emergency departments, according to a nationally representative study led by Todd Florin, M.D., MSCE, from Ann & Robert H.
Certain psychiatric drugs linked with elevated pneumonia risk
A review of published studies indicates that use of benzodiazepines and benzodiazepine related drugs (BZRDs), which are prescribed to treat various psychiatric diseases, may increase the risk of pneumonia.
Bacterial pneumonia far more dangerous to the heart than viral pneumonia, study finds
Heart complications in patients diagnosed with bacterial pneumonia are more serious than in patients diagnosed with viral pneumonia, according to new research.
Research suggests vapers are vulnerable to pneumonia
The vapor from e-cigarettes seems to help pneumonia-causing bacteria stick to the cells that line the airways, according to research published in the European Respiratory Journal.
More Pneumonia News and Pneumonia Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Meditations on Loneliness
Original broadcast date: April 24, 2020. We're a social species now living in isolation. But loneliness was a problem well before this era of social distancing. This hour, TED speakers explore how we can live and make peace with loneliness. Guests on the show include author and illustrator Jonny Sun, psychologist Susan Pinker, architect Grace Kim, and writer Suleika Jaouad.
Now Playing: Science for the People

#565 The Great Wide Indoors
We're all spending a bit more time indoors this summer than we probably figured. But did you ever stop to think about why the places we live and work as designed the way they are? And how they could be designed better? We're talking with Emily Anthes about her new book "The Great Indoors: The Surprising Science of how Buildings Shape our Behavior, Health and Happiness".
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.