“We can hope that people eat two fatty fish meals per week to get their omega-3, as health professionals suggest, but the truth is, they’re not," says Dr. Mary McNiven.
"We need to find another way to get those fatty acids into their diets. The only source of the healthy omega-3 is from animal products, so I think the answer is to enrich something with omega-3 that they’re already eating, and that’s beef.”
Dr. McNiven is a professor of animal science in the health management department of UPEI’s Atlantic Veterinary College. She is investigating how we might make beef healthier by adjusting the feed of cattle.
“If we were talking about pork, the job would be easier,” says Dr. McNiven. “Increase the amount of omega-3 in the pig’s diet, and it goes into the meat. Unfortunately, it also makes the meat oily, fishy and unappealing.”
Cows have a more complicated digestive system to get around. Cattle are ruminant animals, which means that feed must first pass through an organ called the rumen before entering the true stomach.
“The rumen is a large vat that houses a network of bacteria that begins the process of breaking feed down into smaller, more usable pieces,” she says. “We can only feed a small amount of free oil in the diet because higher amounts will harm the bacteria.”
The elaborate digestive system allows cattle to extract as much nutrient as possible from feeds.
“But it is also why you can’t just increase the omega-3 in the meat by feeding a cow something like fish oil. The bacteria can’t handle it, and the cow just ends up becoming sick.”
One other way to get oil into cattle diets is to protect the oil from breakdown by feeding an oilseed that has been heat treated. Dr. McNiven feeds her cattle mixtures of flax, canola and soybean which contain the building blocks for the healthy omega-3 fats. She is looking at the enzyme systems in various muscles of cattle that convert the building blocks into the omega-3 fats to see if she can increase the production of omega-3 in the meat.
Dr. McNiven’s lab is also experimenting with roasting and extruding the mixtures of oilseeds in order to denature the protein to protect the omega-3 building blocks from conversion in the rumen.
Dr. Mary McNiven
“We’re trying to find the balance of how much to roast the oilseeds,” she says. “Roast them too little, and the bacteria convert the building blocks from omega-3. Roast them too much, and the nutrients are damaged so that the animal can’t use them.”
Dr. McNiven has also developed an in-lab method of assessing the different grades of roasted oilseed feeds to narrow down samples to be used in later testing. It’s a promising bit of research that will improve our intake of nutrients, without changing our eating habits.