Current Progressive Cattle digital edition

What World War II taught us about feeding cattle

Vaughn Holder for Progressive Cattleman Published on 23 July 2018
Dr. Vaughn Holder (right) at a feedlot

Nutrigenomics is scientific study of the interaction of nutrition and genes or, alternatively, the effect of nutrition on the expression of genes.

One of the earliest observations of nutrigenomic changes dates back to the end of World War II, when the food embargo in the Netherlands resulted in a famine that reduced average caloric intake of its people to 400 to 800 kilocalories per day. (2,000 to 2,500 kilocalories is considered the requirement.)

Women who were pregnant during this time of nutrient restriction had children who were more likely to become obese during early adulthood, and those children were also more likely to develop late-onset diabetes. Two generations later, children of those children were more likely to be obese by the age of 50. What has this taught us? Even a relatively short-term nutritional intervention can have a long-term effect on successive generations of offspring.

Rather than the traditional concept of changing gene sequences by either breeding or artificial means, programmed nutrition is a program that stems from an evaluation of the effects of nutrition on the expression of genes without changing the gene sequences.

In this case, instead of the nutrigenomics effects being negative, as they were in World War II, the science of nutrigenomics seeks to use this information to improve the long-term health and productivity of animals.

The power to evaluate the effect of a nutritional intervention on the expression of every gene simultaneously provides a powerful tool. Feeding programs can be customized to fulfill specific goals, such as improving immune function, improving production parameters or even modifying meat quality.

You are what your mother ate: Heritable changes in gene expression that span generations

The programmed nutrition concept seeks to take advantage of these nutritional fetal programming effects to bring positive changes to livestock production systems.

For example, in a 2017 study, total replacement of inorganic trace minerals with proteinated trace minerals and selenium yeast in the diet of beef cows resulted in heifer calves out of those cows having confirmed puberty nine days earlier and confirmed pregnancy eight days earlier than their inorganic trace mineral-fed counterparts.

Even more powerful, though, was: Calves born to those heifer calves that remained on the organic mineral program had confirmed puberty 41 days earlier and were confirmed pregnant 18 days earlier than their inorganic mineral counterparts.

In addition, 160 calves from each treatment were fed out in a feedyard under common management and nutrition conditions. Animals coming from the organic mineral-supplemented cow herd had 18 pounds greater carcass weight and a 0.93 percent increase in dressing percent (63.04 percent versus 63.97 percent).

Therefore, we can see these epigenetic fetal imprinting effects can become more and more powerful over time and can be persistent even once the nutritional interventions are removed. This emphasizes the need to look at a long-term nutritional strategy with all nutrients when considering changes in the supplementation strategies of your herd.

You are what you eat: Persistent changes in gene expression within a single generation

Much of the attention in the field of epigenetics is focused on the ability to cause heritable changes in gene expression, like fetal imprinting effects. However, there is plenty of evidence for persistent changes in gene expression within a single generation, driven by a specific nutritional intervention.

This is particularly important in the beef industry, where the segmented nature of the industry may prevent us from fully exploiting the fetal imprinting effects at the feedlot level.

There is significant pressure on the beef industry to eliminate or reduce the use of antibiotics. However, producers and industry stakeholders must balance those pressures with protecting both animal welfare and the sustainability of the beef business. So does the concept of programmed nutrition offer a solution?

Two successive trials with a major cattle feeder evaluated the ability of a nutritional program, developed through nutrigenomics, to be able to raise feedlot cattle in a traditional system without the use of a common antimicrobial agent. A standard feedlot ration was compared to the programmed nutrition ration, which contained no monensin or tylosin.

In the first study, carcass weight of the programmed cattle was higher by an average of 14 pounds (P=0.015); however, dead and rejected cattle numbers tended to be higher, and liver abscesses were significantly higher in the programmed nutrition treatment (13.6 percent versus 26.5 percent, P less than 0.001).

In the following study, the program was refined, resulting again in superior hot carcass weight (927 pounds versus 935 pounds, P=0.03) but with equivalent deads, removals and digestive death rates as the antibiotic-containing control ration. Liver abscesses were also very much improved in the second trial, being statistically equivalent to the control.

This is a simple example of the process by which new technologies can be brought to the marketplace rapidly through the understanding nutrigenomics information gives us.

Rethinking the process of taking beef products to the marketplace

It seems clear we’re not going to be able to change the process of how beef products are taken into the marketplace. The pressure from consumers to remove hormones and antibiotics from beef rations gets stronger every day.

There can be a financial incentive for producers to make some of these consumer-demanded changes. Still, we need to find ways to incorporate some of these changes without sacrificing the welfare of the animals and our industry.

Consumers may demand for antibiotics to be removed from animal rations but, if an animal gets sick, you need to treat that animal with antibiotics. The same would happen if your child got sick, as you would go to the doctor and give them antibiotics to get better.

With the power to select a diet blueprint for an animal through nutrigenomics, we can feed an animal for a specific outcome, whether that is maximizing production or feeding them in a system that does not contain antibiotics.

Is programmed nutrition the key to meeting demand in the future?

Learning from the past is key to preparing for the future. As we learned from World War II, generations to come can be affected by maternal nutrition.

Beef will remain an important protein source, and we must continue to use the tools available – such as programmed nutrition through nutrigenomics – to increase the efficiency of resources, whether that be at the cow-calf or the feedyard stage.   end mark

PHOTO: Dr. Vaughn Holder (right) at a feedlot in Kansas. Photo courtesy of Alltech. 

Vaughn Holder
  • Vaughn Holder

  • Ruminant Research Director
  • Alltech
  • Email Vaughn Holder