Swath grazing - It isn't just cow feed.

Driving around rural Alberta in the winter, it's not unusual to see cows grazing in a swathed forage crop; it would be quite unusual to see younger classes of cattle in that same grazing environment. Dr. Obioha Durunna at Lakeland College is conducting a three-year field study that may change some producers' perspectives, especially those looking to add growth and frame to yearlings over the winter.

This project aims to evaluate a cereal mono-culture crop (oats) against a diverse forage mixture (sometimes called a cocktail crop or cover crop) and determine the production costs and profitability of the mono vs. diverse crop mixtures. With feed accounting for 60+ per cent of the variable costs of most cattle operations, finding ways to reduce these costs puts money back in the producers' pockets. The results of this project will provide producers with data to make more informed decisions about the species of plants to use in a swath grazing situation and how to make it suit their operation's objectives.

For this three-year study, Lakeland College has provided a 30-acre site for Dr. Durunna's project. The site was divided into six 5-acre paddocks. He seeded the areas with either SO1 oats or a commercial forage blend from Union Forage that consisted of oats, turnips, rapeseed, and forage peas. The project started in 2021 and is now in its second year.

In the first year of the project in 2021, all crops were planted in early June, with swathing done on all plots on Aug. 16, 2021. The exception was 30 ft strips in the forage treatments to provide insight into the potential for additional growth from potential late rains with the forage blends. A month later, the remaining crop was swathed.

In the fall of 2021, the paddocks were set up with electric fencing dividing the field into six long paddocks. Forty-two 600-weight crossbred steers (seven per paddock) were randomly assigned to each of the paddocks and, over the course of the study, were provided fresh swath with the fence moved 40ft every 2-3 days. Windbreaks and free-choice minerals were available in all paddocks.

Throughout the study, body weights were collected every two weeks to determine the gain of the animals. At the start of the trial, a rumen pH/temperature bolus was inserted in the rumen of two steers in each paddock for further data capture. Steers went on trial on Nov. 3, 2021 and finished on Jan. 26, 2022.

Results from the 2021-22 winter swath grazing season showed no difference in average daily gain between the steers in both treatments. The forage blend had better overall feed quality than the oats monoculture, which suggests that the adoption of a diverse forage mixture may provide more benefits in the long from more nutritive feed and reduced production risk resulting from unpredictable weather conditions. The diverse diet may also reduce the need for supplemental protein and other nutrients for yearling cattle which would, in turn, reduce the input costs through the costly winter months.

In the second year of the trial, paddocks were seeded in June 2022 with the same treatment as the first year, and swathing took place on Sept. 2, 2022. As in the first year, a 30 ft area was left to grow and was swathed a month later on Oct. 5, 2022.

Since the 2022 growing season was more productive, more animals were added for the 2022-23 grazing season, with 60 600-weight steers separated into six groups of 10 steers per paddock. Recently half of the animals in each paddock were fitted with NoFence collars to learn more about how the technology works in cold weather and how it could be used to manage animal movement during swath grazing. The other five steers in the paddock received a rumen bolus to monitor pH and temperature. Steers went on trial Nov. 15, 2022.

An important aspect of swath grazing is limiting animal access to the windrows, which requires additional time to move the fence every few days. If the animals had full access to the entire paddock from the start, they would selectively graze all the grain and fines from the swaths, leaving courser leaves and stems for later. While it may seem easier to turn the cattle out and let them fend for themselves, the nutritional consequences are too great. In addition, snow plays a role in feed accessibility and can impact intake.