By Karla H. Jenkins
UNL Cow/Calf, Range Management Specialist
The following article is a summary of a 2015 Nebraska Beef Report ( http://go.unl.edu/df7x ). Beef cattle producers grazing cattle on improved or native pastures are often looking for inexpensive ways to increase gains and forage utilization efficiency. Ionophores have been shown to improve gains and efficiency in beef cattle. However, delivering them to grazing cattle can be challenging and expensive. If a grain or by-product is chosen as a carrier, the supplement has to be routinely delivered to the cattle. Cattle producers with integrated operations are also farming during the growing season and may not have time to supplement cattle daily. In addition to the cost of the carrier, producers incur costs associated with time, labor, and equipment. Therefore, a grazing study was conducted to determine if providing Bovatec® in a trace mineralized salt block would improve cattle performance over cattle provided a trace mineralized salt block without an ionophore while maintaining block consumption below 2 oz/hd/d.
Average daily block intake was 1.40 and 1.25 oz/d for the Bovatec® and control cattle, respectively (Table 1 http://go.unl.edu/w9cz). Lasalocid consumption was 193 mg/hd/d. An increase in supplement disappearance for both treatments occurred during the 5th week of the grazing study. There was a rain event during this time, and some loss could have occurred due to rain. However, visual observations indicated that the blocks were largely unaffected by the event. Just prior to the rain event the temperature was over 100 degrees F for 3 days in a row with one day reaching 106 degrees F. It is more likely the spike is true consumption due to cattle standing around the water tanks, more so than a loss from rain. The fact that intake decreased to the lowest intake later that week for both treatments supports this.
Although cattle consuming the Bovatec® block gained 5% more than the control cattle, this was not significant (1.75 vs 1.67 lb/d, respectively). Supplying an ionophore through a self-feeding block may not improve gain compared to supplying mineral alone in a self-feeding block (Table 1). The conclusion of the study was that providing an ionophore through a self-feeding mineral block resulted in less than the targeted 2 ounces/hd/d intake of supplement, and did not statistically improve gain compared to the control mineral block which did not include an ionophore.
Source:unl.edu