Interpretive Summary: Effects of including Sweet Bran or modified distillers grains in the diet of feedlot steers and sorting at terminal implant on growth performance, feeding behavior, and liver abscess occurrence
By: Katie J Heiderscheit, Aubree M Beenken, Erin L Deters, Katherine G Hochmuth, Trey D Jackson, Elizabeth M Messersmith, Allison J VanDerWal, Katherine R VanValin, Joshua M Peschel, Stephanie L Hansen
Sweet Bran, a branded wet corn gluten feed (Cargill Corn Milling, Blair, NE) has been shown to improve performance of feedlot steers and might affect feeding behavior (Parsons et al., 2007). RAMP (a complete starter ration produced by Cargill with high inclusion of Sweet Bran and low inclusion of forage) increased feed efficiency when fed to newly received steers during the growing period when compared to steers fed a traditional receiving diet containing hay, Sweet Bran, and dry-rolled corn (Schneider et al., 2013b). Including Sweet Bran in the diet of feedlot steers during adaptation to finishing diets increased dry matter intake (DMI) as well as meal size (Sarturi et al., 2011). Steers consuming RAMP before abruptly changing to a finishing diet containing Sweet Bran displayed no negative performance effects (Schneider et al., 2014) suggesting Sweet Bran might help buffer the rumen as dietary grain inclusion increases.
Cattle housed together will compete to gain access to a resource. A competitive environment can be triggered by over-stocking pens or disrupting the group hierarchy through sorting of cattle to new pens. Feeding behavior can change when cattle are housed in a competitive environment. For instance, subordinate cows prefer to eat a low-palatability feed alone rather than stand next to a dominate cow and have access to a high-palatability feed (Rioja-Lang et al., 2012). Additionally, competition increases feeding rates (Collings et al., 2011), and greater rates of feed consumption might decrease saliva production in ruminants (Beauchemin et al., 2008). Saliva is critical for preventing ruminal acidosis (González et al., 2012). Ruminal acidosis can damage the ruminal epithelium and allow microbes which populate the rumen to escape into the portal blood, make their way to the liver, and form a pocket of infection (an abscess; Jensen et al., 1954). As such, increasing competition might lead to greater occurrences of liver abscesses (LAs) through decreased ruminal pH.
The objectives of this study were to 1) assess inclusion of Sweet Bran in diets of feedlot steers on performance and feeding behavior and 2) examine the effects of sorting animals at terminal implant on performance, feeding behavior, and LA occurrence. We hypothesized that 1) Sweet Bran-fed steers would have greater performance and slower feed consumption rates and 2) sorted steers would have lesser growth performance and greater LA occurrence.
Read the full article in Translational Animal Science.