Animal Behavior Helps Grass Production

By Kurt Lawton, Contributing Editor

The adage of home-field advantage in sports combines the synergy of being in a familiar place with the energy boost from the home team crowd.

In the animal behavior and grazing world, herbivores like cattle, sheep, and goats gain home-pasture advantage by learning to nourish and self-medicate from a familiar plant landscape thanks to their home-raised mom. This home-field advantage is passed along from generation to generation.

Fred Provenza, professor emeritus of Behavioral Ecology at Utah State University, said the mother plays a crucial role as a model and transgenerational link for her offspring.

HOME-PASTURE ADVANTAGE

"The flavors of what she eats in the pasture are transferred through amniotic fluid to her babies during the last trimester of gestation. Animals born with local adaptation to their mom's pastures perform much better than animals brought into unfamiliar pastures," he says.

In a recent Soil Health Labs podcast (No. 71 on https://www.growingresiliencesd.com/…), Provenza discussed his decades of research on understanding animal behavior and ecology as interconnected systems. He cited a mentor he worked for in his youth, rancher Henry DeLuca, who taught him the value of keeping your heifers as replacements.

"Henry, born in 1900, had a lifetime of working with his hands on the (Rocky Mountains of central Colorado) landscape, and being intimately involved in knowing his cattle," Provenza said. "His stories of bringing in replacement heifers on an unfamiliar high-elevation range stuck with me because Henry could easily find the animals he raised, but not the replacements."

Not only were the replacement animals challenging to locate and move to different pastures (between 8,000 and 11,000-foot elevation), but their conditioning and pregnancy rates were greatly reduced when brought back to the ranch in the fall. Animals spent too much time walking along perimeter fencing seeking ways to escape and find their home.

POWER OF OBSERVATION

"Henry gained all this home rangeland knowledge without the benefit of classrooms or reading books. It came to his brain through his hands when he observed how different subgroups of animals (extended families) used various plants and locations in a landscape," Provenza said.

DeLuca's shepherding insights are similar to the results of research studies showing how genes are expressed epigenetically in particular environments to influence form, function, and behaviors including food and habitat selection.

For example, cattle placed on the same summer range pastures in Oregon and Idaho were separated into subgroups that showed fidelity to particular areas within pastures. As adults, they grew up preferring to live in the locations they learned from their mothers.

Another example Provenza wrote about in his book, "Nourishment: What Animals Can Teach Us About Rediscovering Our Nutritional Wisdom," is how livestock offspring learn from mother and remember for years what and what not to eat and where and where not to go.

"By eating the same foods that a mother ewe eats and cautiously sampling novel foods the mother avoids, young lambs are unlikely to eat poisonous plants to the extent it can be fatal. If it samples a plant that its mother avoided and then becomes sick, the lamb strongly avoids the food thereafter," Provenza wrote. That can't happen when animals are put into unfamiliar environments, which is why they are more likely to get ill and die from over-ingesting poisonous plants.

MOM SAYS EAT MORE GRAIN

Mothers also impact offspring consumption. Six-week-old lambs fed whole-grain wheat with their mothers for as little as one hour per day for five days ate more wheat than lambs exposed to wheat without their mothers. Three years later, with no exposure to wheat beyond those five hours early in life, wheat intake was nearly ten times higher for the mother-led sheep than those exposed to wheat without their mothers.

Provenza said research shows offspring memory is also true for cattle, as calves can remember foods for at least five years. A similar memory pattern exists when calves or lambs learn what poisonous plants to avoid on their home turf from their mother.

During Provenza's second Soil Health Labs podcast (posted 12/11/24 on https://www.growingresiliencesd.com/…), he talked about the grazing ability of cattle, sheep, and goats to consume specific amounts of a wide variety of plant species.

"We did a lot of studies that showed incredible sophistication of animals to limit intake of plants containing secondary biochemical compounds or phytonutrients," Provenza said.

It turned out that these plants were not secondary at all. The phytochemical compounds (i.e., phenolics, terpenes, and alkaloids) interact with primary biochemical compounds and with cells and organ systems in herbivore bodies to influence their grazing choices and their health.

Provenza's research group carried out hundreds of studies that proved how animal likes and dislikes for plant flavors were not caused simply by taste or feedback from the stomach after eating. It emanated as well from cells, organ systems, and gut microbes, telling animals via likes and dislikes for plants what they need to eat to optimize their nutrition and health.

LANDSCAPE BIODIVERSITY IS CRITICAL

"We've come to realize that there is no facet of plant behavior that these compounds are not involved with -- everything from sunscreen and antioxidants to interactions with other plants, to drouth tolerance, and of course to interactions with herbivores," Provenza said.

When animals know their landscape and can eat a variety of different forages that offer varied secondary compounds, they can change the amounts consumed daily. For example, cattle recognize when they reach a toxic alkaloid threshold when eating potentially toxic plants like larkspur, so they'll avoid it for a few days until their body detoxifies it.

They also learn to use appetizers to help the main course go down. For example, an appetizer of tannin-containing plants like sainfoin, birdsfoot trefoil, or serecia can help both cattle and sheep to eat more endophyte-infected tall fescue and shrubs like sagebrush. Finally, secondary compounds bolster health through their antioxidant, anti-parasitic and immune-boosting properties.

Diverse plant communities are thus nutrition centers and pharmacies that enable health prophylactically and therapeutically. Animals foraging on phytochemically diverse pastures require less anthelmintics and antibiotics than animals foraging on monoculture pastures or in feedlots. Overuse of antibiotics in feedlots adds to antibiotic resistance, a global health challenge.

Throughout these two podcasts, Provenza talks in greater detail about how animal behavior and ecology are interconnected systems.

Animals' grazing wisdom reflects an intimate knowledge of the "home field" where they are born and reared. His holistic and insightful views of animal nutrition encourage a reevaluation of conventional agricultural practices through a deeper appreciation for the instincts of animal and landscape well-being.

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