Kittens: Their microbiomes are what they eat

Oct 22, 2012

For animals as well as people, diet affects what grows in the gut. The gut microbial colonies, also known as the gut microbiome, begin to form at birth. Their composition affects how the immune system develops and is linked to the later onset of metabolic diseases such as obesity.

Common wisdom is that cats, by nature carnivorous, are healthiest when fed high-protein diets. Researchers at the University of Illinois wanted to find out if this is true.

"There are a lot of diets now, all natural, that have high protein and fat and not much or carbohydrates," said researcher Kelly Swanson. He and his team examined the effect of :carbohydrate ratio on the gut microbiomes of growing .

One month before mating, eight domestic shorthair female cats were randomly assigned to one of two dry diets: high-protein, low-carbohydrate (HPLC) or moderate-protein, moderate-carbohydrate (MPMC). When the kittens were born, they were housed with their mothers until they were 8 weeks old, weaned, and then fed the same diets as their mothers.

After weaning, the 30+ kittens were twin- and triple-housed within the dietary-group cages. They were allowed to go into a common area furnished with toys and scratching posts to play with people and each other.

"It became quite a party right away," said Swanson. "It was a bit chaotic but fun as well."

Twelve of the kittens became part of the study. The researchers took at weaning and 4 and 8 weeks after weaning. They extracted and used bioinformatics techniques to estimate total .

"This was one of the first studies in cats to use sequencing to really lay out what is in the gut in regards to microbiota and apply it to nutrition," Swanson said.

The researchers found important differences between the two groups in microbiome composition. As they had expected, levels of proteolytic bacteria (which break down protein) were higher for kittens on the HPLC diet and levels of saccharolytic bacteria (which break down carbohydrates) were higher for kittens on the MPMC diet.

They also looked at relationships between the diets and physiology. The kittens fed the MPMC diet had high levels of bifidobacteria, which was linked to higher blood ghrelin levels. Ghrelin is a hormone that stimulates appetite and thus may be linked to weight gain.

At the same time, the bifidobacteria may promote better gastrointestinal health. Low levels in humans have been linked to inflammatory bowel disease.

Other bacteria found at higher levels in the MPMC kittens, including lactobacilli, are also linked to gut health. The researchers found a positive relationship between lactobacilli, blood cholesterol, and blood leptin levels. Leptin is the signal that tells the body to stop eating. Hence, lactobacilli may be linked to cholesterol metabolism, appetite, and body weight regulation.

Although kittens fed the HPLC diet had lower levels of some health-promoting bacteria, including Bifidobacterium, Lactobacillus, and Megasphaera, all the animals were healthy throughout the study.

Swanson hopes to use the associations found in this study as a basis for further research. "There were some interesting observations that could have applications for disease or the practical side of owning a pet," he said.

"The cat is fairly unique metabolically," he added, "But when it comes to gut microbes, there are a lot of similarities to other species. If you feed the bacteria in a cat, dog, or human colon the same substrate, there are probably going to be similar outcomes."

The research has been published online in British Journal of Nutrition.

Explore further: Boy moms more social in chimpanzees

add to favorites email to friend print save as pdf

Related Stories

No link between gut bugs and obesity

Nov 05, 2008

(PhysOrg.com) -- The types of bacterial bugs found in our guts are not a major cause of obesity, according to latest findings from Aberdeen researchers.

Healthy gut flora could prevent obesity

May 25, 2011

Poor gut flora is believed to trigger obesity. In the same way, healthy gut flora could reduce the risk. This has shown to be the case in tests on rats.

Changing pigs' diets alters the gut microbiota

Jun 21, 2012

Including chicory in cereal-based diets of pigs results in profound changes in gut micro-environment, morphology, and microbial population of pigs, according to a study in the June 2012 Applied and Environmental Microbiology. Some o ...

Recommended for you

Boy moms more social in chimpanzees

Nov 24, 2014

Nearly four decades of observations of Tanzanian chimpanzees has revealed that the mothers of sons are about 25 percent more social than the mothers of daughters. Boy moms were found to spend about two hours ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.