THE EFFECTS OF GROUND FLAXSEED FEEDING DURING THE RECEIVEING PERIOD ON MORBIDITY, MORTALITY, PERFORMANCE, AND CARCASS CHARACTERISTICS

M. J. Quinn, E. S. Moore, D. U. Thomson, B. E. Depenbusch,

M. L. May, J. J. Higgins, and J. S. Drouillard

Kansas State University, Manhattan, KS 66506-1600

Summary

            Two trials were conducted to evaluate the effects of feeding low levels of ground flaxseed (0, 2, 4, or 6% of diet dry matter) during the 56-day post-arrival period on health, performance, and carcass characteristics of crossbred beef calves.  Heifers were purchased from a sale barn in Edmonton, Kentucky (Trial 1, n=363, 472 lb initial bodyweight; Trial 2, n=377, 490 lb initial bodyweight) and transported to the Kansas State University Beef Cattle Research Center in January (Trial 1) and April (Trial 2), 2006.  Calves were processed on arrival, and randomly allocated to each of 24 feedlot pens (48 pens total).  Starting approximately 24 hours after arrival in the feedlot, calves were fed diets consisting of 60% concentrate with 0, 2, 4, or 6% ground flaxseed for 56 days, and then were transitioned to a common feedlot diet and fed until harvest.  Morbidity, mortality, growth performance, and carcass characteristics were measured for each pen of cattle.  Feeding flaxseed improved performance and health of calves during the 56-day post-arrival period in Trial 1.  Feed intake, daily gain, and efficiency all were greater in cattle fed flaxseed compared to cattle fed the control diet.  More importantly, improvement in gain during the 56-day post-arrival period resulted in heavier carcass weights at harvest.  Yield or quality grade were not influenced by prior feeding of flaxseed.  In Trial 2, health and performance were not affected by diet.  Heifers in Trial 2 had low mortality rates, possibly indicating that they were not severely challenged with respiratory disease.  In conclusion, the impact of feeding flaxseed is very favorable in cattle that are immunologically challenged.