Location: Livestock Issues Research2012 Annual Report
1a. Objectives (from AD-416):
Our primary objective associated with this subordinate project is to determine if live yeast or yeast cell wall supplementation improves the overall health and performance of cattle during the early phases of the feedlot period.
1b. Approach (from AD-416):
Twenty-four recently weaned calves weighing approximately 500 pounds will be transported to our research facility. Upon arrival, all calves will be weighed and placed into one of three treatment groups in a manner that balances the body weights across treatments. The three treatment groups will consist of: 1) Control group, n = 8 calves, fed a standard receiving diet; 2) Live Yeast group, n = 8 calves, fed the Control diet containing live yeast; and 3) Yeast Cell Wall group, n = 8 calves, fed Control diet containing a yeast cell wall product. Calves will be fed their respective diets for 21 days. On day 22, all calves will be fitted with indwelling jugular catheters and probes to measure rectal temperature. On day 23, all calves will be subjected to an immune challenge to determine their innate immune response. Serum samples collected during the study will be analyzed within the Livestock Issues Research Unit for hormones and proinflammatory cytokines associated with the stress and immune response. Additionally, performance data will be collected to determine if the yeast supplements alter performance prior to and after the immune challenge.
3. Progress Report:
The overall focus and objective for this project is to determine if live yeast or yeast cell wall supplementation improves the overall health and performance of cattle during the early phases of the feedlot period. Alternative methodologies that enhance immunity and subsequent health of calves entering a feedlot have the potential to decrease costs associated with medication usage and the loss of gain associated with illness, and are consequently in high demand. Recent research at the Livestock Issues Research Unit in Lubbock, Texas, has focused on the potential of yeast products as a non-antibiotic alternative feed supplement that can improve productivity during several periods of cattle production, specifically by enhancing immune function and improving overall health. During this past year, a collaborative study was conducted with scientists from Texas Tech University and Lesaffre Feed Additives to determine the effect of yeast supplementation on performance during a period of heat stress. Results indicated that supplementing yeast products during a period of heat stress improved feed intake and gain without jeopardizing the health of the cattle. Additionally, yeast supplementation appeared to enhance the overall health status of the cattle, which resulted in a reduced immune response when cattle were exposed to endotoxin. This study suggests that yeast products may be a viable feed supplement for cattle entering the feedlot in order to reduce the negative effects of illness on productivity while at the feedlot. Results from this collaborative study were presented at a scientific meeting during this fiscal year, and a manuscript is being prepared for submission to a peer-reviewed scientific journal.