Groundbreaking research could help ranchers optimize free-range grazing
A group of cows, heifers and calves heads out to pasture. The cows and heifers have been outfitted with pedometers and GPS collars so U of A researchers can study their grazing habits. (Photo courtesy Carolyn Fitzsimmons)
A new University of Alberta research project could help ranchers customize their cattle to the type of pastures they have, creating economic and environmental benefits along the way.
Launched this past summer, the research involves tracking the movements and feeding habits of grazing cattle, looking to identify genetic traits that could lead to breeding more efficient livestock.
The project opens up a sweeping, multi-dimensional approach to precision ranching, said lead investigator Edward Bork, a professor of rangeland ecology and management in the Faculty of Agricultural, Life & Environmental Sciences (ALES).
“This is pioneering work. No one has ever at this scale linked together the productivity and associated economics, genetics and environmental outcomes of free-range grazing.”
Unlike other livestock-based industries where producers can create precise feeding and activity environments to maximize efficiency and minimize operational waste, cattle ranchers face the challenge of managing animals that roam and feed as they please in huge pastures, Bork noted.
“These animals are out in natural landscapes and continually make decisions on where to go, how far to travel and what to eat. Those decisions can affect some factors of ultimate productivity.
“We want to try to identify animals that are going to select the right habitat, the right forage species to optimize their weight and productivity, while at the same time not overgrazing pasture resources.”
“This is pioneering work. No one has ever at this scale linked together the productivity and associated economics, genetics and environmental outcomes of free-range grazing.”
Testing existing technology from around the world, such as GPS ear tags and pedometers, Bork and a team of 10 other scientists are tracking grazing cattle at the U of A’s Roy Berg Kinsella Research Ranch to learn more about their individual behaviour. They’re also using previously banked genetic data from the herds to aid their work.
The findings from the three-year research program will give insight into the choices the animals make in terms of habitat and food preferences, Bork noted.
“Questions to be addressed include, for example, what habitats do cattle select in a given landscape? Are they willing to walk to the top of a hill to preferentially graze? Do they select forest, grassland or shrub plant species while meeting their optimal nutritional requirements? What individual plant species are they more willing to consume given that there are hundreds of species to choose from, and how does this affect their weight gain and environmental footprint?
“Ultimately, we’re trying to understand the decisions cattle make as they make a living in these complex landscapes.”
Watching what cattle eat — and where they find it
How much energy cattle expend in their search for food is also an important question, he noted.
“Animals have time allocation budgets just like we do. They allocate their time between searching for food and actual feeding. Some animals may spend a lot of time searching and less time eating; their attention spans are low and they’re restless, always moving and never happy with what they’re feeding on.
“That’s a potential concern because those cattle are wasting energy, making less energy available for growth and lactation.”
Genetics of a given animal under grazing conditions also need to be more closely explored, said co-researcher Carolyn Fitzsimmons, an Agriculture and Agri-Food Canada beef genetics and genomics scientist in ALES.
“We’ve been measuring feed efficiently in the feedlot for quite some time, but we aren’t certain how that efficiency translates to the grazing animal. We need to relate feedlot setting performance to grazing performance, or quantify grazing performance on its own. That will provide information and tools to Alberta’s cow-calf producers to help them select feed-efficient, productive, healthy grazing cattle.”
By monitoring the animals’ movements as they graze, researchers can link that activity to the existing information they have about the genetics of the cattle.
“We can look for markers that associate with the behaviour of the animal, and those markers would become really powerful,” said Bork.
A marker for browsing, for example, could allow livestock breeders in northern Alberta to select for a cow that prefers to graze on bush pasture. Or ranchers with overgrazed types of pasture could select for cows that will instead eat another available type of plant.
“A rancher might be able to mix and match the genetics to align their forage demand with what is available. In doing so they could customize their herd to the feeding grounds they have.”
Less methane, less stress on rangelands
The project also has advantages for the environment, Bork said.
“We are measuring methane production from cattle while grazing on pastures to assess whether there’s a link between the plants being eaten and increasing or reducing methane production; then we can look for genetic markers in the cattle that tell us whether that animal may be efficient or inefficient at producing methane, and also link that information to levels of production in the cow-calf unit.”
Selecting cattle that prefer to graze a particular type of pasture could also result in less stress on rangeland plants, he suggested.
“Once pasture conditions improve, that provides other environmental goods and services such as carbon storage and more wildlife habitat and diversity, while also boosting plant production and subsequent grazing opportunities.”
Bork and his team are also testing an emerging trend in precision ranching: virtual fences, using wireless technologies and sensors to control the location of livestock. The technology could potentially eliminate the need for building and maintaining physical fencing.
“It means with one stroke on a keyboard, producers could build a boundary for their herds. And if they wanted to move it, it could be done from their pickup truck. It provides a form of highly flexible on-the-go management to change where, when, how long and how intensely their animals graze.”
In addition, for the first time, the team will use a non-invasive technique of quantifying dietary composition of free-ranging animals by examining manure samples and using DNA markers to compare what’s in them to a plant reference library.
It will allow for a rapid test of hundreds of animals to discover exactly what they’re eating.
“It’s a new approach of plant-fingerprinting in fecal samples, which has never been done in the context of animal science studies,” Bork noted.
The project includes several graduate students and a post-doctoral researcher, which helps build needed expertise in the science of precision ranching, he added.
“This work will serve as a significant demonstration showcase as to what these technologies we are testing can do. There’s lots of interest out there among existing producers.”
Collaborators on the project include U of A Faculty of Science professor James Cahill, and researchers from Agriculture and Agri-Food Canada, the University of Saskatchewan and Thompson Rivers University.
The project is funded by Alberta Beef Producers through the Canadian Agricultural Partnership, and by Results Driven Agriculture Research as well as Alberta Innovates.