Arm & Hammer Animal and Food Production
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WEBINAR: Even at low levels, Clostridia impacts herd health.

Posted December 08, 2020 by Tom Rehberger, Ph.D., Director, Research and Product Development


There are few organisms found on a dairy that are as prevalent and invasive as Clostridia. Because they form nearly indestructible spores, Clostridia can survive even the harshest environments. That’s why we find Clostridia in manure, soil, feed and virtually anywhere on the dairy and inside the cow.

A study1 conducted by Arm & Hammer Animal and Food Production took more than 20,000 fecal samples from 509 farms across 30 states. Of those samples, 98 percent contained Clostridia, and 80 percent of those contained Clostridia perfringens.

The graph below shows the levels of C. perfringens found in the fecal samples [Figs. 1 and 2]. Note that a majority of samples had Clostridia levels in the 100 to 1,000 colony forming units per gram (CFU/g), with an even distribution between samples with less than 10 CFU/g and the upper end of more than 10,000 CFU/g.

clostridia perfringens levels in cow fecal samples chart

clostridia perfringens levels in calf fecal samples chart

The study also collected feed samples to determine Clostridia presence. Of the haylage, corn silage and TMR samples collected, the TMR samples had by far the highest clostridial levels [Fig. 3].  That means that, even at low levels, your cows could be eating significant amounts of Clostridia every day. Simple math shows how this could happen.

clostridia loads in feed samples chart

If the Clostridia level in a TMR is at 100 CFU/g, that means there are 45,400 CFU per pound (100 x 454 grams/lb.). If a cow eats 100 pounds of feed per day, that means she’s consuming more than 4.5 million CFU each day, more than enough to create infection that leads to any number of disorders, including hemorrhagic bowel syndrome (HBS).

Because your cows could be consuming Clostridia at high levels, it’s important to build resilience against pathogens by providing protection that limits the impact of clostridial infections. Feed ingredients that contain Bacillus, including CERTILLUS from Arm & Hammer Animal and Food Production, have been proven to limit the impact of Clostridia.

Bacillus help control clostridial populations by producing many antimicrobial compounds that limit the growth of Clostridia inside the gastrointestinal tract. In addition, research2 shows that the specific and proprietary Bacillus strains found in CERTILLUS can increase the types of proteins that tighten junctions between cells responsible for creating a barrier that prevents pathogenic bacteria, like C. perfringens, from entering the animal.

The positive impact of feeding CERTILLUS can help cows be more resilient to infection. This can create more consistent feed intakes and fewer off-feed events, which lead to a decrease in issues resulting from a compromised GI tract and, subsequently, fewer cows in the sick pen. And, as Clostridia levels decline in the presence of Bacillus, fiber-degrading bacteria are allowed to proliferate, including those that break down cellulose and hemicellulose in the GI tract.

Clostridia can have a devastating impact on the health of your herd, even at low levels. It’s important to take steps to protect your cows with products, like CERTILLUS, that can help control clostridial infections.


1 ARM & HAMMER survey of US dairies. Data on file. 2020.
2 Lillejoj, et al., 2017. USDA Beltsville


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