Inactivation of Mycobacterium avium ssp. paratuberculosis in cattle manure by lactic acid fermentation is dependent...

Area of Science:

• Veterinary Microbiology
• Environmental Science
• Agricultural Science

Background:

• Mycobacterium avium ssp. paratuberculosis (MAP) is an intestinal pathogen shed in feces, posing environmental risks via contaminated cattle manure.
• Effective decontamination of animal waste is crucial for preventing disease transmission and environmental contamination.

Purpose of the Study:

• To evaluate lactic acid fermentation (LAF) as a method for inactivating MAP in cattle manure.
• To assess the efficacy of different carbohydrate sources (oats and saccharose) in enhancing MAP inactivation through LAF.

Main Methods:

• Cattle manure was amended with oats and/or saccharose and incubated at 21°C for 8 weeks.
• Microbial shifts were monitored using cultural methods to determine MAP inactivation.
• RT-PCR was used to detect IS900 genome fragments, indicating the presence of MAP DNA.

Main Results:

• Squeezed oats significantly reduced culturable MAP below detection limits within 35-42 days.
• Supplementation with saccharose further reduced MAP inactivation time to 21 days.
• Saccharose alone did not effectively inactivate MAP, with bacterial counts similar to the control; however, MAP DNA (IS900 fragments) persisted throughout the experiment.

Conclusions:

• Lactic acid fermentation with specific carbohydrate sources, particularly oats, is a viable strategy for reducing culturable MAP in cattle manure.
• LAF presents a promising, natural approach for decontaminating cattle manure, mitigating the environmental spread of paratuberculosis.
• While culturable MAP is reduced, the persistence of MAP DNA suggests further research into complete inactivation methods may be warranted.