A new technical bulletin from Chr. Hansen explains how its ruminant direct-fed microbials (DFMs) — Probios® Complete and Probios® Precise — work in dairy cattle to deliver a number of important benefits.
According to Dr. Keith A. Bryan and Steve Schwager, who authored the bulletin, there is growing interest in learning how microbial communities within an organism — known as microbiomes — affect the physiological processes of the host.
For example, gut microbiomes in genetically obese mice have been shown to have a higher proportion of certain bacteria than genetically thin mice.
When gut bacteria from obese mice were transferred to the guts of lean mice, the lean mice gained body fat.
Newborn ruminants begin to establish their individual microbiome soon after birth with the introduction of bacteria from the dam, Bryan and Schwager state. Research has demonstrated that a diverse microbial population in the gut positively influences the development of the rumen wall and subsequent digestive function.
Supplementing the dairy cow’s natural microbiome
Inspired by these mouse studies, researchers in Israel have found that the relative proportions of two specific bacteria in the rumens of lactating dairy cows were strongly correlated with daily milk-fat yield. These results suggest that DFMs have tremendous potential to supplement natural microbiomes and improve the physiological outcomes of the target host animal.
Because so much of the dairy cow’s digestion and metabolism is dependent on the work of microbes, manipulating the bacterial population in the rumen and lower GI tract can significantly impact the dairy cow’s physiological processes.
Chr. Hansen has developed several microbial feed supplements with proven benefits for dairy cows. Containing three distinct strains of Enterococcus faecium, Probios® Precise and Probios® Complete have been shown to improve ruminant gut health by regulating pH, scavenging oxygen, binding toxins, and inhibiting pathogenic bacteria. These modes of action can result in an improvement in starch and fiber digestibility and decrease the incidence of sub-acute rumen acidosis (SARA), while field trials have demonstrated a 3- to 4-pound increase in energy-corrected milk.
In precise, but clear terms, the technical bulletin goes on to explain the various ways in which the Probios® products optimize digestive function and support overall health in dairy cows, including:
- Bacteriocin production. Certain lactic acid bacteria, including E. faecium, produce antagonistic substances called bacteriocins and can compete with pathogens for the same nutrients. By inhibiting the growth of these pathogens, these strains help boost the cow’s immune system, decrease fecal shedding and, consequently, reduce the overall pathogen load in the environment. Additionally, a 2012 study showed that ruminants fed an E. faecium probiotic had more immune cells in the small intestine than unsupplemented control animals.
- Synergy of E. faecium and yeast. Live-cell yeasts are also considered direct-fed microbials, even though they are fungi and not bacteria. Research indicates that in addition to consuming oxygen and increasing rumen pH, certain live yeasts can bind pathogens. In studies, the live yeast used in Probios® products was found to significantly reduce the adherence of E. coli and Salmonella to the gut.
- Competitive exclusion. Probiotics may also help prevent the colonization of the gut by harmful bacteria through competitive exclusion. Also known as Gause’s Law, competitive exclusion is based on the premise that two species that compete for the same resources cannot coexist in stable populations. While beneficial, non-pathogenic bacteria are a normal part of a dairy cow’s microbiome, supplementing additional beneficial bacteria in the form of probiotics will increase the protection against pathogenic bacteria, reduce infections and strengthen her immune system.
Based on these proven benefits, Bryan and Schwager conclude that DFM use in dairy cows will increase as producers realize the economic benefits of this technology. To learn more about the benefits of Probios® Complete and Probios® Precise and how they work in dairy cows, download the free technical bulletin here.