Understanding Fetal Programming in Cattle

Understanding Fetal Programming in Cattle

Fetal programming has been heavily researched and discussed over the last 20 years in the beef industry. Yet, many still feel like the concept is complex and confusing.

Here’s a simple breakdown of the theory, the outcomes and how to nutritionally meet your cows’ needs in gestation for successful fetal programming.

What is fetal programming?

At its most basic definition, fetal programming is the concept that cow nutrition and management during gestation can have lasting effects on calf performance. Essentially, it’s the theory that you can program a calf for how it will perform for the rest of its life.

North Carolina State University defines fetal programming as an insult during critical times of fetal development, which can have long-term effects on offspring. In this case, insult is defined as times of nutrient restriction to the cow.

What causes poor fetal programming?

Periods of drought, poor grass quality and cold stress are all examples of nutrient restriction that could cause poor fetal programming during critical developmental times.

Over 75% of the fetus develops in the last two months of gestation. During this time, the calf is drawing a vast amount of nutrients from the cow as it develops muscle, fat, organs and carcass characteristics. If nutrient restriction occurs during this critical developmental time, the cow will eventually restrict nutrients to the fetus.

Short-term and long-term results of poor fetal programming

The short-term impact of poor fetal programming is often low-birthweight calves or chronically ill calves with underdeveloped immune systems. Chronically ill calves, or chronics as they’re often called, can severely impact the profitability of an operation.

The long-term impact of poor fetal programming can result in calves with poor fertility, meat quality, metabolic functions and immune system strength. Unfortunately, these undesirable traits can be passed on to subsequent offspring and prolong issues in a herd. Still, more research needs to be conducted to determine the generational impact of fetal programming.

How to improve fetal programming

Research studies from the University of Nebraska evaluated the effects of providing protein supplementation during late gestation. Cows either received or didn’t receive 1 lb. per day of a protein supplement (42% crude protein) during late gestation. Results showed that steers born to cows that received the protein supplement were heavier than male offspring born to non-supplemented cows.

In addition, one study showed greater percentages of carcasses grading Choice and greater marbling scores for steers from cows supplemented with protein during late gestation.

Learn more about fetal programming in this webinar presented by Dr. Jennifer Young, Ralco Ruminant Nutritionist.

What are the nutritional requirements of a cow late in gestation?

Late gestation cow energy requirements ramp up by 25% and protein requirements by 10%. In addition, mineral requirements of the cow also increase.

The cow’s demand for macronutrients such as calcium and phosphorus increases because of fetal growth. Furthermore, cows require higher levels of copper, selenium, zinc and vitamins A and D for proper fetal body and immune system development.

According to Dr. Jeff Hill, Ruminant Nutritionist for Ralco, it’s best to use a breeder mineral during late gestation to meet the cow’s needs. A better name for a breeder mineral is a calving mineral.

“A high-quality breeder mineral should be fed at least 60-90 days prior to breeding, and that’s late gestation,” said Dr. Hill. “This will ensure the cow has high-quality colostrum, a healthy calf and a successful breeding season.”

How Ralco can help with fetal programming

Let Ralco help you get your cows ready for calving with high-quality mineral and protein supplementation.

Get started with a free mineral consultation to evaluate the needs of your herd during late gestation.


  1. Moriel, Philipe. “Fetal Programming: Cow Nutrition and Its Effects on Calf Performance: NC State Extension Publications.” NC State State Extension Publications, NC State, 26 Feb. 2016

  2. Stalker, L. A., D. C. Adams, T. J. Klopfenstein, D. M. Feuz, and R. N. Funston. 2006. Effects of Pre- and Postpartum Nutrition on Reproduction in Spring Calving Cows and Calf Feedlot Performance. J. Anim. Sci. 84:2582–2589.

  3. Stalker, L. A., D. C. Adams, T. J. Klopfenstein, D. M. Feuz, and R. N. Funston. 2006. Effects of Pre- and Postpartum Nutrition on Reproduction in Spring Calving Cows and Calf Feedlot Performance. J. Anim. Sci. 84:2582–2589.

  4. Larson, D. M., J. L. Martin, D. C. Adams, and R. N. Funston. 2009. Winter Grazing System and Supplementation during late Gestation Influence Performance of Beef Cows and Steer Progeny. J. Anim. Sci. 87:1147–1155.

  5. Hall, John B. “Management in Late Gestation Is Important to Two Calf Crops.” Extension Beef Cattle University of Idaho, University of Idaho,15 Jan. 2006.