Feed for Thought
By Lynn Petrak,
special-projects editor

Nutrients added to feed affect safety, quality and, ultimately, profitability for protein producers.
If you are what you eat, then the diet of your food source is important as well. From a farm-to-plate perspective, livestock feed does have an effect on consumable proteins.
“People who raise animals obviously want them healthy. Feed conversion can be bad if you don’t have healthy animals, too,” notes Dean Cliver, professor in the population health and reproduction department at the University of California-Davis.
Kristjan Bregendahl, assistant professor of animal science and poultry nutrition at Iowa State University, agrees it is largely understood by producers that nutrients are the fuel that powers the food supply, whether in flocks or herds.
“The No. 1 goal with diet is to meet all the nutrient needs of birds — that is where different minerals and vitamins come into play,” he says of his work in poultry feed.
While stewardship of the land and humane treatment of animals have long been deemed inherently beneficial by those in the business of raising livestock, there are some nutritional nuances that have emerged in recent times.
“What has really come to light in the last 10 years in research work, by a lot of people, is that if we want to optimize an animal’s performance and meat quality, then we try to never let him have bad day — we don’t let him lose weight, run a fever, get sick or contract a disease,” says Bill Mies, a retired professor at Texas A&M University who consults with the global beef group at the Elanco Animal Health, a division of Eli Lilly and Co.
According to Mies, the link between animal health and product quality is becoming more apparent, and documented.
“Three to five days of illness is enough to change the eventual quality of that product somewhere down the road. We can pick them out in the tenderness studies,” he reports.
To guard against diseases, viruses and other conditions that may impact meat and poultry quality — not to mention spur concerns over food safety and integrity — producers, university scientists, feed companies, animal-health companies and industry organizations have spearheaded many efforts related to the nutritional composition of feed and its impact on animal health. Ultimately, there is payback for preventing problems before they start.
“That combination of nutrition and animal-health programs has saved us untold millions of dollars of losses that were inherent for years. Animals were sick, they were downers, it took labor to doctor them, a certain percentage would not respond and would die, and some didn’t catch up. And then you go back to the tenderness in that the meat was comprised,” says Mies of some of the changes that have taken place in just the past several years.
Addition formulas
Certainly, there are many examples of nutrients added to basic feed or, more rarely, water, that are designed to optimize the health of the animal. Supplements can include traditional vitamins and minerals as well as amino acids and other substances.
One recent area of improvement is akin to the drive to enhance human health by boosting immunity via nutrient intake. Mies, for example, cites findings on the ways in which livestock are weaned and raised.
“It used to be that we expected them to adapt and go on to the pasture or feed yard. Now, we find if we feed the calf good vitamins and mineral supplements along with their feed and give him a vaccine, he’s more likely to respond to it and be immune, and then able to withstand stress. He’s also less likely to lose weight and get sick,” he says.
Other discoveries over the past few years are tied to the role of nutrients in certain species, which can also vary on a regional basis.
“That is key in having the immune system work correctly. We’ve found, for example, that in many areas of the country they had copper deficiencies,” says Mies of cattle production, adding that he and others continue to study the effects of other vitamins and minerals on certain animals in particular regions.
In addition to vitamins and minerals, other types of enhancements are being mixed into feed. Bregendahl underscores the use of enzymes in some forms of poultry feed. “Enzymes help birds utilize the nutrients in various feed. It contributes to better absorption,” he explains. Recently, additional substances have garnered attention, also mirroring trends in human diets.
“Probiotics are being promoted for animals as well as humans, where they are specially developed cultures that are supposed to colonize innards and protect us,” says Cliver, who is also quick to note that probiotics must be taken regularly to have such effects.
Feed can be altered in other ways with the goal of preventing health problems among animals. A recent European study, for instance, showed that controlling carbohydrate fractions in swine diets may help control certain enteric bacterial diseases in pigs.
A natural evolution
One movement that has put a wrinkle of sorts in the addition of nutrients in feed is the surging growth of the natural and organic market for meat and poultry. The use of antibiotics is not allowed in many natural and organic proteins, and there are limits on some types of other additives as well.
Mies, for his part, says that an animal’s health is even more important if it is bound for the natural or organic segment of the global food chain.
“There is no treatment alternative, so the animal can’t get sick in the program,” he says. “That’s why it’s even more important that we have the nutritional status of the animal at 100 percent before they make the trip to the feed yard, because in a natural program, there is less or no opportunity to treat them and keep them in the programs.”
Some replacements for antibiotics, or additives that help prevent any conditions that would otherwise require antibiotics, fall into the nutrient category as well. Bregendahl, for instance, reports that work is being done to replace antibiotics and growth hormones with nutrients that improve health and potentially treat problems.
“Some of that research has been done with probiotics, with the idea that ‘good’ bacteria outcompete ‘bad’ bacteria,” he explains, adding that prebiotics have been applied as well for various functions.
Meanwhile, another issue tied to the composition of feed is safety. The scare over melamine in pet food that made headlines last year also spilled over into the livestock feed market, after some chicken and pig feed was said to be mixed with melamine to make it appear as if it had higher protein levels. To help prevent such problem in the future, Chinese and U.S. officials in December signed an agreement designed to enhance the quality of feed and food shipped here from China, resulting in a legally binding series of commitments from China.
Another safety-related issue, this one linked to fears over the spread of bovine spongiform encephalopathy (BSE), is the possible use of ruminant tissue in feed for ruminants. Although ruminant-to-ruminant feed bans were enacted years ago here and in other countries around the world, reports still circulate periodically in media outlets and other channels about possible animal protein found in feed, resurrecting the issue among consumers and other groups.
Future feed
With higher feed costs and concerns about quality and safety not abating anytime soon, nutrient additives in feed will likely remain a prominent subject among producers and, further down the line, those that pay for livestock and raw material for processing. That, in turn, means more research and applications on animal nutrition.
“Looking ahead, I think there are a lot of opportunities,” agrees Mies, who uses changes in corn breeding as an example. “We are seeing real specialization now. Before, we would use corn, because it was corn and we would all use corn. But now we are growing it for a bunch of different opportunities.”
Such genetic-based work can be applicable to other feed components as well, and forage breeding also has been the subject of work in university and company laboratories, he adds. Even now, there are more feed mixes that are, if not individually customized, then at least increasingly tailored for certain species, regions and other attributes.
“Mineral companies do a huge number of custom blends, because the mineral content of grasses and water are so different in many locations around the country,” Mies says.
Still, day-to-day realities on the farm and ranch may mean that the realm of the possible may not be the realm of the probable. Cliver observes that it can be difficult to ensure that ruminants are germ-free animals.
“It’s a matter of commitment, and it’s also a question of how much you are willing to pay,” he explains.
Mies, too, says that there is always more work to be done to optimize animal nutrition, on the way to animal health.
“I think everyone in the business would like a day when we put needles away, but we can’t yet,” he says.