Westway Trading Corp. Research Report
SUSPENSION SUPPLEMENTS BENEFIT RATION CONSISTENCY!!!!!!
Joseph M. Harris, Ph.D.

Liquid supplements have long been thought to provide nutrients contained with more consistency than comparable dry supplement forms, but direct scientific data is lacking. Furthermore, in many situations dietary adequacy is predicted on the basis of single bunk samples most often obtained just after mixing and placement. This method may detect some mixing errors but can't account for possible interactions between the ration and the animals themselves (sorting in the feedbunk). If this is indeed a factor it is possible that all animals are not exposed to the same dietary nutrient and additive concentrations.

Previous efforts by Pritchard'95 (SDSU Beef Cattle Research Report pg. 48) compared the impact of supplement form on performance of for finishing steers. Some 200 steers(initial weight circa 800 lb.) were fed a 90% concentrate finishing diet for 105 days. The study included four diets in which liquid supplement provided supplemental vitamins, minerals and monensin and comparisons were made to a control diet in which these components were provided in a pelleted form. Final rations were approximately 73% dry matter in all cases due to the inclusion of small grain silage and high moisture corn. Steers fed the liquid supplement containing diets outperformed steers fed the dry supplements with higher average daily gains(4.2 vs. 3.9 lb./d P =.05) and dry matter intake 23.4 vs. 22.4 lb./d P< .05). At the conclusion the animals fed the liquid supplements were an average of 32 pounds heavier and had consumed 105 pounds dry matter basis more feed. Feed efficiency was not significantly affected. If one were to assume a value of $0.60 per pound for the animal weight and ration value of $0.06 per pound, animals fed the liquid supplements provided an increased net revenue of $11.70 per head. The author suggested that improve performance may have increased uniformity of the diet and feed additive consumption and thereby enhanced animal performance.

 Our research desired to compare supplement form (pelleted Vs suspension) affects on diet homogeneity from day to day as well as the possible effects that time after feeding (animal sorting) might have on component composition. We were concerned that data may be challenged on the basis of possible interaction with over-all dietary moisture concentration so a diet containing significant silage concentration was desired.. For the study the cooperation of a large commercial feedyard planing to switch from a pelleted supplement form to a suspension supplement was obtained. Yard was feeding a diet containing silage and pelleted supplement. Just prior to change of supplement source 5 samples were obtained from each of two separately fed pens at times of feeding, two hours latter and four hours later. Sampling was repeated on 3 consecutive days. Diets were then changed to include a suspension supplement and the sampling procedure as described above was repeated. Dietary concentration of calcium ( dry basis) was chosen as the most reliable indicator of supplement concentration. Some 180 independent measurements were made.

Statistical analysis of the data was done within pens because it was possible that the animals within the pens could impact the results of the measurements. (DATA IS SHOWN IN GRAPHICAL REPRESENTATION BELOW) In both pens significant (P < .04) variation in the day to day average calcium concentration did occur. Suspension usage resulted in a reduction in the amount of variation observed. Comparison of the effects of time post-feeding had on calcium concentration are perhaps the most interesting results of this study. In both pens, time of sampling had significant effects (P < .014 and .1 for pens 1 and 2 respectively) when dry supplements were included in the diet. These affects were not observed when a suspension supplement was utilized. With this observation one might conclude that observed day to day variation was solely attributable to rate of inclusion variation in the mill. IN THIS STUDY SUSPENSION SUPPLEMENTS REDUCED DAY TO DAY VARIATION IN CONSTITUENT DENSITY AND ELIMINATED THE IMPACT OF PREVIOUS ANIMAL SELECTION.