PSXII-10 The effects of different mineral supplementation strategies on feedlot performance of mineral deficient cattle

Abstract

Abstract Mineral deficient cattle that enter a feedlot have been documented to have increased morbidity and mortality rates and decreased feedlot performance. The objective of this research was to explore current practices used by feedlot producers when receiving mineral deficient cattle. To accomplish this, forty steers were blocked by weight and mineral status, then assigned to one of four treatment groups: control (Con; n = 10), industry mineral requirements (IND; n = 10) top dressed on TMR fed, 2X industry mineral requirements (2XIND; n = 10) top dressed on TMR fed, and MultiMin® injection at labeled dose (MM; n = 10). All steers received the same ration in pens equipped with GrowSafe® bunks. Standing liver biopsies were collected on day 0, 5, 10, 20, 30 and 40 and analyzed for mineral content. Steers were weighed on day 0, 14, 28, 41, 56, 70, 84, and 110. Average daily gain (ADG), dry matter intake (DMI) and feed efficiency (FE) were recorded. After the trial, steers were harvested at a commercial facility and carcass data was obtained from the plant. There were no differences (P > 0.05) in weight gain or overall ADG between treatment groups. When analyzed over time, treatment had an effect (P < 0.001) on liver copper and selenium concentrations, but no effects (P > 0.05) were observed on liver manganese and zinc concentrations. Additionally, when DMI was analyzed over time, effects (P < 0.05) of time, treatment, and treatment*time were observed, and effects (P < 0.05) of time and treatment*time were observed on FE. Treatment had no effect (P > 0.05) on carcass data. These data indicate that different mineral supplementation strategies have diverse effects on feedlot performance and liver mineral concentrations over time.