Bodybuilders pump up using a chemical that may reduce post-extrusion Salmonella contamination of pet foods. In an experiment, scientists reduced and eventually eradicated Salmonella growth on dog kibble by spraying the pet food with a naturally occurring substance, 3-hydroxy-3-methylbutyric acid (HMB).
Dietary supplement stores sell the same chemical to athletes hoping to tack on muscle mass and reduce recovery times. HMB may have dual effects as a bacteria fighter and functional ingredient in food for working and athletic dogs, according to one scientist involved in the experiment.
HMB fought Salmonella on dog kibble
In three trials of an experiment, researchers used five different concentrations of two types of HMB sprayed onto kibble after extrusion. The scientists applied free acid or calcium salt HMB in solutions with concentrations of 0.1, 0.3, 0.5, 0.9, and 1.5 percent HMB in water.
After spraying, the scientists inoculated the kibble with a strain of Salmonella bacteria. As a control, some kibble received no HMB, but was contaminated with Salmonella. The experimenters measured the presence of the bacteria on the kibble at intervals for two weeks.
Both types of HMB seemed to reduce Salmonella growth compared to the control. Indeed, after two weeks, HMB treatments eliminated detectable Salmonella contamination, while the controls still harbored the dangerous pathogen. The results were published in the Journal of Food Protection.
Although these results seem promising, one study author noted that HMB needs more testing before it can be used for commercial-level control of Salmonella.
“As with any scientific hypothesis, it generally takes repeated studies to have widely accepted support for the hypothesis,” John Fuller, Jr., PhD of Metabolic Technologies, told Petfood Industry. “We are confident in the data we have generated as this was generated in two independent laboratory settings. Thus, this could provide the basis for commercial use; however, these results should be repeated in an actual commercial setting.”
Salmonella control and benefits for working and athletic dogs
HMB can be found on the shelves of dietary supplement stores, where is marketed as a means to build lean muscle and speed healing after hard weightlifting sessions. Also, physiologists and biologists have found empirically evidence to back up those marketing claims. Fuller noted that HMB may have similar benefits for working and athletic dogs, along with fighting Salmonella.
“The intended use would be as an anti-microbial when added to or coated on the food, but yes it could have a physiological effect as well similar to the effect seen in humans,” he said. “While numerous studies have demonstrated that HMB helps human (and equine athletes) recover from strenuous exercise and train and work harder, there are no published studies showing this in dogs. We did conduct some pilot studies and the data from these indicated a distinct benefit for racing and working dogs.”
Pet food formulators need to be aware of human used for novel pet food ingredients, noted consultant Ryan Yamka during his presentation at Petfood Forum 2017. Human competition for ingredient can reduce its availability for pet food and increase its price. However, Fuller doesn’t foresee this as a problem for HMB.
“No, while this could be a large market for HMB, the market supply for HMB should be able to keep up with the established human use as well as the developing animal market for HMB,” he said.
Fuller’s employer, Metabolic Technologies, produces HMB, along with other dietary supplements. The lead author of the study, Ann Rigdon-Huss, PhD, is a postdoctoral researcher in Kansas State University’s Department of Grain Science and Industry. Eurofins Microbiology Laboratories researchers were also involved.
