After extrusion processing, certain carbohydrate sources may be more fermentable by the gut bacteria of adult dogs than others, leading to nutritional benefits for the dog. Scientists tested how heat, steam and pressure processing of barley, corn, wheat, rice and oat flours affected the fermentative digestibility of the carbohydrates they contain by Labradors Retrievers of varying age.
“We advise that food meant for medium-size breed dogs that are six months and older should be made with more potato, oat and wheat flours rather than other sources,” wrote the researchers in Veterinarni Medicina. The researchers conducted their work at Erciyes University, Kayseri, Turkey.
Digestibility of extruded barley, corn, wheat, rice and oat flour in dogs’ guts
For the study, the researchers worked with two six-month-old, two two-year-old and two eight-year-old male Labrador Retrievers in a kennel. The dogs ate commercial dry diets. The scientists collected their feces. The poop served as an inoculant to establish a colony of bacteria from the dogs' gut in laboratory glassware. The various carbohydrate sources were added to the poop soup. By measuring the fermentation of carbohydrates by gut bacteria left in the dogs’ feces, the researchers could approximate the conditions in the living dog’s intestines.
The barley, corn, wheat, rice and oat flour was purchased from a company in Kayseri. To simulate the effects of extrusion, the flours were subjected to 134 degrees Celcius and 2.1 bar pressure for 14 minutes using an autoclave. Before use, the processed barley, corn, wheat, rice and oat flour was cooled under laboratory conditions.
“We observed that the digestion levels of the dogs differed between different starch sources; the extruding process positively affected the digestion of the starch sources (barley flour, corn flour, rice flour and oat flour), which were not pre-treated before extrusion,” wrote the researchers.
