University of Nebraska looks at ways to better manage grazing distributionWritten by Gayle Smith
What if producers could sit down, talk to their cattle and ask what pushes them to overgraze certain areas and not graze others at all? Since cows can’t talk to us, the University of Nebraska-Lincoln (UNL) has developed another way to find out this information.
Research is underway at UNL looking at ways to better manage cattle grazing behavior. According to Mitch Stephenson, forage specialist with UNL, scientists used to spend a lot of time observing cows and following them around to obtain data on grazing patterns.
Now, with the help of GPS units, research can take place behind an office desk.
Current research on three separate herds in the Nebraska Sandhills and one at the Gudmundsen research facility is looking at grazing patterns and attempting to determine if genetic markers exist that will determine if a cow is a hill climber or a bottom dweller.
These cows have been fitted with collars that transmit their grazing patterns through GPS.
The goal of this project is to link genotype to grazing locations. In past studies, Stephenson says they have found specific genetic markers that were significantly associated with specific chromosomes of the cow.
“Initial research shows grazing decisions may be a heritable trait that can be passed on through genetic selection of certain bulls and cows. The next step is to develop a SNP (single nucleotide polymorphism) panel that detects favorable genotypes for grazing distribution,” Stephenson explains.
This genetic test may cost an estimated $25 to $30 a head, but eventually, it may be worked into a genetic expected progeny different (EPD) panel.
Stephenson sees this potential development as important for the future management of grazing areas with cattle.
“If we can develop these genomic EPDs, producers will be able to select cows that will either be hill climbers or bottom dwellers. By being able to select cattle based on how they graze, cattle may better fit into a producer’s program,” he says. “Producers may be able to select cattle that will move away from the water source in the heat of the day to graze.”
Previously, Stephenson has participated in research attempting to modify cattle behavior.
“In modifying animal behavior, we are focusing our grazing for a specific purpose,” he says. “Ultimately, we are trying to influence the decisions that animal makes. Like dogs, specific breeds of cattle have specific purposes.”
“If we look at the breeds and the individual genetics, we can select animals to target graze for our purposes,” he explains.
Other grazing techniques
Currently, the placement of water sources, cross-fencing, the use of supplements and low stress cattle handling are the most effective ways to control grazing distribution, Stephenson says.
“Adding new water sources and cross-fencing pastures can help with rotating cattle so they graze more in underutilized areas,” he explains. “The problem is, it is costly to put in fencing and water. In some areas, fencing may be too expensive and not feasible. Some producers utilize electric fence to save costs, but in some cases, electric fence won’t work.”
When areas are underutilized, Stephenson says harvest efficiency and production per acre declines.
“It leaves forage out there that could have been grazed,” he says. “Usually, these are the areas further from water or on steeper slopes.”
“Cattle seem to prefer the riparian, lush areas of the pasture and avoid upland areas. Consequently, some of these riparian areas may become degraded and constantly overgrazed for years if producers can’t find a way to fix the grazing distribution,” Stephenson adds.
Stephenson shared a story about a riparian area in central Wyoming that had a very shallow and wide stream channel and poor fish quality. Nearly 25 years ago, the Bureau of Land Management and the rancher using this land for grazing made a decision to cross fence the area and change the management.
“They now use this area during weaning and preg checking,” Stephenson says. “By switching the timing of grazing, the stream channel has narrowed, and now we can walk up and down the bank of this creek. There are also more brook trout flowing through it. It has helped the grazing distribution because during the dormant season, the quality of vegetation is more uniform.”
This instance shows producers that if they have distribution problems in their pastures, a simple change of the time of grazing may help relieve some of the pressure it gets late in the growing season, Stephenson notes.
Fencing and supplements
It is common practice to fence out ecological areas.
In the Sandhills, producers may use cross-fencing to graze meadows and upland areas separately. Although this works, Stephenson cautions producers about cattle walking up and down the cross-fenced area, causing blowouts to develop.
Using supplements to attract cattle to less utilized areas has also been used successfully, Stephenson continues.
“When feeding supplements, take advantage of the supplement and put it in an area that has little grazing use,” he says. “Protein and low-moisture block supplements have had good success in pulling animals into these underutilized areas. If the supplement is self-limiting, it helps keep them in an area.”
However, the range specialist adds that while these blocks or tubs can be moved around to lure the cattle into underutilized areas, cattle will have a limit to how far they are willing to travel.
“We have found supplements to be most successful in moderate terrain, but it is a good challenge to see how far we can get them to travel,” he adds.