Protecting the next generation

SIOUX FALLS, S.D. — What happens in utero affects the health and longevity of the next generation.

Billy Brown, an assistant professor at Kansas State University, spoke about using dam nutrition to set calves up for success during the Central Plains Dairy Expo March 26 in Sioux Falls.

Brown presented on the effects of prenatal exposure to choline and methionine, how dam heat abatement can play a role in the life of their offspring and the effects of parent body conditioning on calves.

When there is a female in utero, her eggs are present by the time she is born. Those cells are prepped for the environment they think they are going into, Brown said. If a dam is starved and her offspring is being starved at the same time, this tells the calf to prepare for a lifetime of potential starvation, Brown said. When they have nutrients later, the animal stores them for potential future scarcity.

“We could be altering what happens to that animal later in its life as an adult by what’s happening to the dam or even the sire at conception,” Brown said.

Brown said if the mother is obese, the offspring could be obese as well into the third generation. Knowing these affects can play a role in improving cow nutrition on the farm.

Brown started his postdoctoral research at the University of Wisconsin-Madison in January 2021. At that time, he and other researchers were doing a transition cow study looking at rumen-protected choline, a dietary supplement. They were also following the calves for a certain period of time to see its effect.

The calves that had prenatal choline exposure had reduced stress levels, more ideal respiration rates, better rectal temperatures and tumor necrosis factor, which is produced by immune cells during an immune response.

“Maybe these animals … are able to fight off infection, maybe a little better than their counterparts that did not receive exposure to choline,” Brown said.

During their study, the researchers found choline affected body weight and marbling. Brown said there were areas it did not affect, such as feed efficiency, slaughter weight or carcass weight.

“This should be really exciting to the beef industry and the dairy industry,” Brown said. “We don’t really know of any way to nutritionally increase marbling other than just giving more energy to feedlot animals.”

Brown presented another study conducted at the University of Florida. This study watched calves that were exposed to rumen-protected choline prenatally.

The death loss in the control group of calves which were not exposed to choline prenatally through their dam was 23%, whereas the calves that were exposed to choline the death loss was 9%, Brown said.

Brown also presented data from studies that researched rumen-protected methionine prenatally. The studies showed it increased calf weaning weight.

There may be environmental events that are affecting cows as well. Things like heat stress and cold stress can potentially affect the offspring, Brown said.

UW researchers have been doing studies regarding heat abatement and its effect on offspring.

Based on the study Brown presented, during heat stress, calves that were cooled prenatally live longer in the herd and averaged 300 more days of life than the calves that were not cooled in utero.

“You get another lactation out of those cows,” Brown said.

A calf that is heat stressed in utero has decreased birth weight and weaning weight, Brown said.

Prenatal choline and methionine can promote early growth, potentially enhance carcass characteristics and maybe enhance milk production, Brown said. Prenatal cooling has benefits for the cow and an increase in offspring milk production, Brown said.

“Anything we do on a dairy farm, whether it’s your dairy farm or somebody you work for, we need to be considering our return on investment,” Brown said.