Spore forming vs non-Spore forming bacteria in Probiotic Products

Probiotics for Dogs/Cats: What's the difference among products?

Two broad categories of bacteria are used in probiotics, spore forming, such as the genus of Bacillus and vegetative such as the non-spore forming genera of Lactobacillus, Bifidobacterium and Enterococcus. Which ones are used in probiotics makes a big difference in its efficacy. While some yeast and fungi that are also used as probiotics, this blog is about the two broad categories of bacterial species. 

Spore forming bacteria:

Spores are meant for survival in stressful conditions and therefore, spore forming ones are extremely durable and can be very difficult to destroy even under extreme temperatures. They can survive drought, extreme temperatures, and low pH, including that of the upper digestive tract (or stomach).  Once favorable conditions return, like when they reach the lower digestive tract, the protective proteins dissolve the spore coating and the bacteria can then resume their normal functions. 

Compared to the widely used vegetative bacteria of Lactobacillus, Enterococcus or Bifidobacterium genera, bacterial spores of Bacillus genus offer the advantage of a higher survival rate during the acidic stomach passage and better stability during the processing and storage of the food product. Furthermore, studies have shown that spore itself exerts an immunostimulatory effect which serves to exclude the colonization of the gut by harmful pathogens. This makes them a much better fit for fortification as probiotics in the pet food products. 

Non-Spore forming or Vegetative bacteria:

On the other hand, non-spore forming ones used in probiotics are common vegetative bacteria. They are much more susceptible to environmental stresses like heat, air, and desiccation as well as manufacturing conditions, such as extrusion, heating, drying, or even changing storage and environmental conditions. More importantly, their cells tend to be sensitive to the extremes of acid and alkaline conditions, as found in the stomach and small bowel. Studies have shown that most are quickly killed off in the harsh, acidic environment of the stomach and therefore, your pets may not be able to get the full benefit no matter how many different types or numbers they may be present in the product. 

These non-spore forming vegetative bacteria are much more commonly used in probiotics than their spore forming counterparts, primarily because of cost. Probably >90% of probiotics sold in the pet food industry are multi-strain, Lactobacillus, Bifidobacterium or Enterococcus based formulas.

So, how to separate the chaff from the real, good?

It's actually quite simple if you just pay a little attention to the label. Only spore forming strains begin with the word "Bacillus." If a strain listed on a label begins with anything else, it is one of the non-spore forming, more fragile bacteria. Most likely they are Lactobacillus or Bifidobacterium or Enterococcus or their blends.

What's in Science4Pets:

Unlike the industry common vegetative types that are used in a vast majority of the probiotic products, Science4Pets (www.science4pets.com) uses the two most effective spore forming species, Bacillus coagulens and Bacillus subtilis. Many of our competitors even try to confuse regular customers by providing the number of species from Lactobacillus, Enterococcus, and Bifidobacterium genera, whereas others mention the relatively high cfu count of the same species as if that makes up for the defective product.

For further info on probiotics, please check these scientific peer reviewed journal publications:

Casula and Cutting (2002): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC127533/pdf/1491.pdf

Bader et al (2012). https://www.wageningenacademic.com/doi/10.3920/BM2011.0039

Hong et al. (2005): https://academic.oup.com/femsre/article/29/4/813/493366