Feedlot Nutrition in Today’s Climate Tactics For Improving Animal Health and Productivity By Zachary Smith, Ph.D. Department of Animal Science, South Dakota State University Three factors that influence the profitability of a cattle feeding enterprise include: an abundant supply of feeder cattle, readily available and economically priced feed, and a favorable production environment. For example, in South Dakota, we are fortunate to be close to an abundance of quality feeder cattle and feedstuffs. However, South Dakota must combat wintertime and summertime weather conditions which challenge even the best cattle feeders. Challenges to cattle and their caretakers in the wintertime include cold temperatures, wind, snow and freezing rain, all of which result in undesirable pen surface and cattle hide conditions. Challenges to cattle and their caretakers in the summertime include warm weather and humid conditions, coupled with very long days with limited opportunity for nighttime cooling. Mitigation of Environmental Stress in Feedlot Cattle Bedding application as a means to improve cattle comfort during wintertime has been commonplace for Northern Plains cattle producers for many years. However, the exact degree to which bedding application improves growth performance has not been well established. As such, an experiment was conducted at the Ruminant Nutrition Center in Brookings, South Dakota, from January to July of 2019. The goal of bedding application was to ensure all steers within a bedded pen had a dry spot to lay down at all times during the course of the experiment. Steers that received bedding were provided on average 4 lbs (as-is basis) of wheat straw bedding per day. The average ambient temperature and the average wind chill was 5.2°F and -0.3°F for the first 36 days on feed (January to February) and 39.8°F and 37.3°F for the cumulative feeding period that lasted from January to July. Steers from the bedded treatment had 4.2% greater body weight on day 36, 48% increased average daily gain, and were 74.4% more efficient in the first 36 days. During the entire finishing SPRING DIRECTIONS 2023
period, steers from the bedded treatment had increased average daily gain by 21%, greater dry matter intake by 5.9%, improved feed conversion by 14.6%, and required 35 fewer days on feed to reach an industry acceptable level of rib fat compared to nonbedded steers. The return on investment (ROI) for bedding after accounting for labor, equipment and material needs ranged from 2:1 to 1:1 depending upon bedding material cost. While the ROI was modest with more expensive bedding, a key point here is that one will likely incur the cost associated with bedding cattle no matter what they choose to do (i.e. the extra 35 days of yardage and feed costs for the non-bedded steers). Another factor to consider is for an integrated crop-livestock business the nutrient value of the crop residue will be returned to cropland as part of the manure, hence, reducing the net cost of the bedding. There are also less tangible, but still important, benefits to bedding that should be considered like enhanced visual appeal of cattle to be sold as backgrounded feeders and improvements in overall cattle comfort and welfare. These data indicate that enhancements of growth performance for bedded steers compared to non-bedded steers were not solely attributable to increased dry matter intake, but rather, reducing the impact of cold-stress on their maintenance energy requirement. Summer in the Northern Plains is generally quite pleasant. There are times, however, when summer feeding conditions can severely impact cattle growth performance. Typically, the worst summertime feeding conditions occur sometime during June or July. Warmer weather coupled with limited nighttime cooling and humidity create many challenges to cattle feeders. While we cannot control Mother Nature, we can work to ensure cattle comfort and productivity by altering time of feeding, providing access to additional sources of water, and not shipping or handling cattle during extreme heat events. In the summer of 2022, we had a set of black-hided steers on NATIONAL CATTLEMEN
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