Trillions of bacteria inhabit the intestines but most of the time they are good bugs. They maintain intestinal health and prevent bad bugs from gaining a foothold. Unfortunately, the balance between good and bad is tenuous, and the slightest intestinal upset can tip it so that the bad bugs overgrow.
Probiotics are the tools that can help re-establish the bacterial flora. They can also be used for economic gain.
How many times have you heard the recommendation of eating yogurt after a course of antibiotics to re-establish the intestinal flora and resolve diarrhea? This is a probiotic at work. Yogurt can help, but more effective products are available.
Probiotics also benefit people with Crohn’s disease, a serious inflammatory bowel disease. They help reduce inflammation and normalize bowel function.
Probiotics are oral products containing live microbes that are non-pathogenic and don’t cause disease. The bacterial species in probiotics are chosen for their capacity to grow in the intestine and their ability to inhibit multiplication of pathogenic bacteria.
Probiotics have many promising uses in livestock. The United States Agricultural Research Service found adding bifidobacterium lactis bacteria to piglet diets enhanced innate immunity in piglet colons. In a separate study, piglets given a worm-induced infection absorbed nutrients better and had a better response to worm infections if their diets included probiotic bacteria.
In chickens, probiotics have been investigated for their role in controlling salmonella infections. Certain lactobacillus bacteria overgrow the natural lactobacilli that chickens have in their gut and then go on to inhibit salmonella growth.
Inoculating one-day-old chicks with the correct bacterial species can help control intestinal diseases. Though doing this may sound simple, the real stumbling block with mass inoculation is the probiotic itself. A lack of consistency in the organisms between batches must be overcome.
Another use of probiotics is inducing changes in body composition and boosting feed efficiency. Feeding probiotics containing bacterial species with an enhanced ability to manufacture amylase coupled with a high starch diet, which the enzyme amylase breaks down, results in increased growth and better feed in piglets.
Milk yield can be boosted by feeding dairy cattle a probiotic containing either enterococcus bacteria combined with a yeast culture or a certain lactobacillus species. Probiotics can also increase daily gain and feed efficiency in feedlot cattle and decrease the incidence of acidosis.
Lactobacillus added to cattle feed can also significantly reduce the frequency of E. coli H0157:H7
in feces, which is blamed for hamburger disease. This could help reduce the occurrence of this pathogen in fresh meat.
It’s unclear exactly how probiotics provide their benefits, but we assume they work by promoting better digestion of food and enhanced absorption of nutrients. Studies show that it is important to select the right bacterial species for the job. Once researchers identify the appropriate species, the next challenge is to dependably grow them in culture, creating a consistent commercial product.
Jeff Grognet is a veterinarian and writer practising in Qualicum Beach, B.C.