Pencillium mycotoxicosis is a condition caused by the consumption of feed contaminated with Penicillium mycotoxins. These biologically active metabolites, produced by several Penicillium molds, pose health risks to livestock.

Exposure to these metabolites can cause mycotoxin poisoning if consumed at high enough concentrations for extended periods of time.

Penicillium molds are typically referred to as “storage molds” or “silage molds” because they are well-adapted to grow in improperly stored dry grains and ensilaged forages.

Insufficient aeration of grains, for example, can lead to moisture buildup that increases grain temperature and attracts insects that promote mold growth.

Many different Penicillium mold species are also found in silage because they are well-adapted to grow and produce mycotoxins in an environment of low oxygen and pH.

The prevalence of Penicillium mycotoxins in dairy cattle feeds is largely unknown since dairy farmers usually produce and store their own feed, and silage contamination typically worsens during the feeding season due to air exposure.

Ruminants were once thought to be resistant to mycotoxicosis because their rumen microbiota is capable of biotransforming mycotoxins to less toxic metabolites.

However, recent research raises question about this assumption since rumen microflora do not detoxify all mycotoxins, and factors such as age, genetics and mycotoxin exposure concentration greatly contribute to rumen biotransformation efficiency.

Additionally, several Penicillium mycotoxins possess antimicrobial properties that may disrupt rumen microbiota function and biodiversity.

Mycotoxicosis is difficult to diagnose in its subclinical form. It can manifest as hidden pathological lesions in the kidney, liver and tissues of the immune system, depending on toxicological interactions among the mycotoxins and sensitivity of the livestock species.

Diagnostic biomarkers of organ and tissue function, however, can be measured in blood, urine and milk to assess subclinical mycotoxicosis before production losses occur.

Assessing the risks of mycotoxin exposure to livestock is challenging since the mixture of mycotoxins in feed can vary depending on the types of mold species contaminating the feed and environmental cues such as temperature and humidity that influence mycotoxin production.

Until recently, detection of the Penicillium mycotoxins in cattle feed has largely missed the radar of governing bodies and the livestock industry. Now, with implementation of programs, farmers can monitor mycotoxin hazards in their feed.

Animal health experts can integrate this exposure data with diagnostic biomarker data to characterize the risk of mycotoxin exposure to the dairy herd.

Since mycotoxin production during storage is influenced by many factors, implementation of appropriate feed mill and farm management practices is essential to keep mycotoxin production under check.

Feed, crop and farm specialists can be of great help in this area by monitoring temperature, air flow and moisture control during feedstuff storage, and by supplementing animal diets with anti-fungal agents, mycotoxin binders and rumen-health promoting agents.

Timely and efficient cleaning of feed mills, grain storage facilities and farms can also aid in mycotoxin control.  PD

Se-Young Oh is also from the Department of Animal and Poultry Science, University of Guelph. Swamy Haladi is with Haladi Consultancy Services in Bangalore, India.

References omitted due to space but are available upon request. Click here to email an editor.

• Neil Karrow
• Department of Animal and Poultry Science
• University of Guelp