General health
In young commercial livestock, such as turkey poults and piglets, body weight and growth rate are good indicators of the health of the animal. Animals raised in the dirty, crowded environments of commercial farms are generally less healthy (and therefore weigh less) than their counterparts born and bred in cleaner homes. In turkeys, for example, this phenomenon is known as "poult growth depression", or PGD.[48]
Supplementing the diets of these young farm animals with L. reuteri helps them to largely overcome the stresses imposed by their unhealthy habitats. Commercial turkeys fed L. reuteri from birth had nearly a 10% higher adult body weight than their peers raised in the same conditions.[49] A similar study on piglets showed L. reuteri is at least as effective as synthetic antibiotics in improving body weight under crowded conditions.[50]
The mechanism by which L. reuteri is able to support the healthy growth of these animals is not entirely understood. It possibly serves to protect livestock against illness caused by Salmonella typhimurium and other pathogens (see above), which are much more common in crowded commercial farms. However, other studies have revealed it can also help when the growth depression is caused entirely by a lack of dietary protein, and not by contagious disease.[51] This raises the possibility that L. reuteri somehow improves the intestines' ability to absorb and process nutrients.[12]
