Tom: Jill Larson is a nutritionist with CRYSTALYX® Brand Supplements. I'm Tom Martin, and Jill is here to discuss fetal or developmental programming. Thanks for joining us, Jill.
JILL: Thank you.
Tom: And first, what is fetal programming?
JILL: Fetal programming, also known as “developmental programming,” is the concept that the maternal environment during gestation has lasting impacts on the offspring. By “environment,” we are talking about environmental factors that could include maternal stimulus or an insult that could be nutrition-related, weather-related stress, toxins, disease or other distress factors in general.
The impact on the calf could affect how prepared the calf is to live in the world outside of the dam, including things like overall development and health of the calf at the time of birth, and throughout its life as well, including poor growth, productivity and negative efficiency traits later on, including carcass traits and reproductive performance.
So, essentially, a poor maternal environment, such as nutrient restriction during pregnancy, may negatively impact that calf throughout its life and may not allow that calf to reach its genetic potential.
Related article: Take care of your cows and they will take care of you
Tom: Talk to us about the origins of the concept of fetal programming.
JILL: The fetal programming concept came from the human health side during the Dutch “Hunger Winter” of 1944–45. It showed that the nutrient restriction to pregnant mothers impacted the child's health, depending on the different stages of trimester of pregnancy the mother was in. Dr. David Barker actually originated the term “fetal programming” in the U.K. and Europe when studying birth records of humans. What he found was that heart disease, diabetes and cardiovascular disease risk were all the more common to people who were born with lower birth weights due to fetal under-nutrition during this time, or other maternal stressors.
This, in turn, happens similarly in livestock-production settings, like in periods of drought conditions or when they're not provided their nutrient requirements during pregnancy and lose weight and body condition as a result.
Tom: Why is it important to remind cattlemen to pay closer attention to their calves out in the pasture during the extremes of summer or winter weather?
JILL: It's important to make sure cattlemen are looking at their cows in terms of body condition, as that's an indicator of the nutrients they are receiving. Most cattlemen often think about supplementing their calves toward the end of pregnancy, and that's because nearly two-thirds of fetal growth is occurring during that last one-third of gestation. But along with this, there's also organ maturation occurring, which is why cattlemen ultimately think about supplementing during that time.
Tom: What's happening with the development of the calf during early pregnancy, and why is it important at this early stage to pay attention to the cow’s intake of nutrients?
JILL: In order to get to that point of exponential growth during late gestation, early pregnancy needs to be set up so that the right pieces are in place. Although fetal nutrient requirements during early-to-mid gestation are minimal — really only making up nearly 12 percent of the cow’s total requirements from a production standpoint — nutrient intake is crucial during early gestation, when the cow is reaching her greatest nutrient requirements to produce milk for the calf. She must also have enough nutrients to rebreed in a timely fashion, in addition to her individual nutrient requirements for maintenance.
Tom: When is it especially necessary to supplement cows with additional nutrients?
JILL: It's especially important to supplement during early pregnancy as this is the time when fetal organs are developing. It’s important that there are enough nutrients for the essential organs — such as the liver, lungs, brain, kidneys and other organs that are essential for survival — are set up early in pregnancy. But then, during late gestation, it's just as important for those organs to fully develop and for the birth weight to be high enough for calf survival once it is born.
Tom: Is there a time during pregnancy when the fetus may be less vulnerable to nutrient restriction?
JILL: That's really a hard question to answer across the board for every type of production system, as nutrient availability through pasture conditions or feed is different across the country. But, in general, if you think about a time during gestation when you could pull back, it would be during mid-gestation, considering that the pasture conditions are at least good after the calves are weaned.
Prior to late gestation, the cow’s nutrient requirements are at the lowest in her production cycle. Additionally, studies have shown that cattle are better at compensating for poor nutrition toward the beginning of pregnancy compared to other species, and it won't have as negative an impact on the calves down the road.
Tom: What are some consequences of poor maternal nutrition during pregnancy and the impact on the calf?
JILL: There’s been a variety of studies done on an assortment of diets and nutritional plans. During late gestation, if cows are nutrient-restricted, research has shown that calves may be slow-growing, have problems at weaning, and there are negative impacts on productivity.
Some research measuring the effect of late gestation as far as nutrient restriction has resulted in calves having a decrease in birth weight, compared to calves that are born to cows that were fed to meet their nutrient requirements. This decrease in birth weight could indicate smaller and potentially less-mature organs and reduce their ability to get up to feed — especially in cold conditions — and get colostrum.
Tom: Jill, how would you recommend cattlemen provide the nutrients to their cows to program the fetal development of their calves?
JILL: There is a variety of ways to get the nutrients to the cows during gestation through supplementation — and to the cows who aren’t pastured during gestation and year-round. Cows can be fed a supplement depending on their condition, whether it is to increase energy or protein during late gestation and through the winter months or to provide minerals during the springtime or fly control over the summer.
Really, the easiest way that will save you time and labor is providing a CRYSTALYX Brand Supplement. By putting out a self-fed CRYSTALYX barrel, it will give you peace of mind that the cows are being offered those essential nutrients — thats energy needed for pregnancy, even when you're not on the pasture with them.
Tom: Is fetal programming a commonly accepted idea among cattle farmers?
JILL: It really is. I’ve been to a number of meetings in which it’s discussed as not necessarily a new concept, but it's something that a lot of cattlemen are really interested in. There are more and more research and findings as far as what nutrients [to offer] and the timing of nutrients that are being offered to the cows, and how that impacts the calf’s productivity down the road.
Tom: And what would you say is the potential impact of successful fetal programming on the farm or even on the industry?
JILL: It's really in both. As far as other studies in late gestation, some have measured performance of heifer calves from cows that were supplemented or were programmed correctly during gestation. Those calves had heavier weaning weights and pre-breeding weights going into that breeding season. In turn, they had greater pregnancy rates overall. In particular, more heifers that calved in the first 21 days being programmed during that fetal development phase had positive impacts.
Their counterparts in the feedlot side, those calves were treated less while in the feedlot when they were born to supplemented cows during gestation. The majority of illness and death in the feedlot segment is from bovine respiratory disease, or BRD. It’s possible that those dams’ nutrient requirements during gestation were met, and that could decrease the risk of respiratory diseases later in life, potentially from improper organ development and, in this case, lung function.
Tom: Jill Larson is a nutritionist with CRYSTALYX Brand Supplements. Thank you for joining us, Jill.
JILL: Thank you.