Investigation of the Impact of Mineral Status and Use of an Injectable Mineral on Beef Cattle Performance

Adequate trace mineral status of feedlot cattle decreases losses during shipping and improves marbling score (MS). Utilizing an injectable trace mineral, at the start of the finishing period, improved average daily gain (ADG), body weight (BW) and hot carcass weight (HCW). Trace mineral supplementation is important to beef cattle performance, and improves response to stress. Injectable minerals improve recovery after a stressful event, and enhance performance

Trace mineral supplementation in feedlot cattle: implications for the inflammatory response, growth, and carcass characteristics

Trace minerals are important components of many biological functions, including growth and development, and the immune response. Trace minerals are often supplemented to cattle, but interactions within the rumen and poor bioavailability can lead to decreased trace mineral status. Additionally, stressors such as transit and disease challenges, and perhaps growth-promoting technologies, may alter trace mineral needs, although this relationship has not been investigated. This research was designed to: 1) examine the effect of trace mineral source and concentration on ruminal dry matter digestibility and mineral solubility, 2) determine the effect of trace mineral status on the response to a trace mineral injection in feedlot steers, 3) determine the effect of a trace mineral injection prior to transit, on beef cattle response to transit and growth and carcass characteristics, and 4) investigate the interaction between the β- agonist ractopamine hydrochloride and a supplemental Zn-amino acid complex in growth performance of feedlot cattle. It was hypothesized that improvements to trace mineral status through supplementation would improve cattle health and growth performance. After completion of our first objective, it was determined that inorganic (sulfates) trace mineral supplementation decreased ruminal dry matter digestibility, but hydroxylated trace mineral supplementation had no impact on dry matter digestibility, relative to no trace mineral supplementation. Additionally, Mn and Cu from hydroxy sources were less soluble in the rumen, and Cu from hydroxy sources was equally soluble in the abomasum when compared with the sulfate source. Hydroxy trace mineral sources are less soluble in the rumen, which can prevent negative trace mineral and dietary component interactions within the rumen. After completion of our second objective, we determined that steers with mildly deficient trace mineral status experienced greater body weight loss in response to transit. Additionally, trace mineral injection can increase liver Cu and Se for up to 30 d post-injection, and can improve marbling score and ribeye area regardless of previous trace mineral supplementation. After completion of our third objective, it was determined that a trace mineral injection 28 d prior to transit, or feed and water restriction did not change the physiological response to transit or feed and water restriction, but did cause a decrease in growth performance for the 14 d period post-transit. However, there was no overall effect on growth performance or carcass characteristics when the entire feeding period was evaluated. Trace mineral injection is an effective way to rapidly increase trace mineral status, but may be most effective in improving growth performance and immune function in cattle with less than adequate trace mineral status. Finally, after completion of our fourth objective, it was determined that increasing supplementation of a Zn amino acid complex (30, 60, and 90 mg Zn/kg diet DM) to a diet that already contained 88 mg Zn/kg diet DM led to a linear improvement in average daily gain, feed efficiency, final body weight, and tended to increase hot carcass weight in steers that were also supplemented with ractopamine hydrochloride. The Zn requirements of cattle supplemented with a β-agonist may be greater than previously estimated, as demonstrated by the improved growth response to Zn supplementation in ractopamine hydrochloride supplemented cattle. Overall, this research suggests that trace mineral supplementation to feedlot cattle above documented requirements may be most beneficial in cattle with inadequate trace mineral status, or cattle experiencing rapid growth in response to a growth-promoting technolog

Comparison of Trace Mineral Repletion Strategies in Beef Cattle to Overcome a High Antagonist Diet

It was observed that diets with high sulfur and molybdenum decreased markers of copper, selenium, and manganese after 90 d. In a 62-d trace mineral repletion period, steers receiving an injection of Multimin90 had the most rapid improvement of copper and selenium status by d 14, while it took 28 d and 42 d for copper and selenium status to improve in steers supplemented with 150% of national recommended concentrations from either an inorganic and organic blend, or only inorganic trace minerals. Further research is needed to understand the optimal trace mineral supplementation strategy to overcome dietary antagonisms without creating economic loss for producers

The Influence of Supplemental Zinc and Ractopamine Hydrochloride on Mineral and Nitrogen Retention of Beef Steers

The objective of this study was to ascertain how ractopamine hydrochloride supplementation and Zn supplementation affects N retention and Zn absorption in beef steers. No interaction was detected between ractopamine hydrochloride supplementation and Zn supplementation (MIN x BA strategies). There was no effect of ractopamine hydrochloride inclusion on Zn absorption. However, there was an increase of Zn retention with increasing concentrations of supplemental Zn. Additionally, N retention was increased by supranutritional Zn supplementation and also by ractopamine supplementation. Increased N retention may help explain previously noted improvements in cattle performance when fed ractopamine hydrochloride and supranutritional concentrations of Zn

Effect of Varying Trace Mineral Supplementation of Steers with or without Hormone Implants on Growth and Carcass Characteristics

The utilization of hormone implants and the supplementation of trace minerals have become well adopted management strategies in the feedlot industry. When hormone implants increase rates of growth in feedlot cattle, this could increase the demand for trace minerals to support those rapid rates of growth. In this study, an aggressive implant strategy dramatically increased growth rates and HCW, without having negative effects on marbling score. It was also observed, regardless of hormone implant, trace mineral supplementation tended to increase overall ADG and steers supplemented at industry consultants recommended concentrations had a 33 lb increase in HCW compared to cattle that received no trace mineral supplementation. This would suggest that hormone implants remain a good return on investment and the current national trace mineral recommendations may not be adequate to support the optimum growth finishing beef steers

Effects of Original XPC on Newly Weaned Beef Steer Growth Performance and Antioxidant Defense

The objective of this study was to determine the effects of increasing inclusions of Diamond V Original XPC, a yeast fermentation product, on newly weaned beef steer performance and antioxidant defense. There was no effect of Original XPC on growth performance in the current study; however, blood measures indicated greater antioxidant capacity and lesser oxidative stress for steers fed XPC at 14 g/d. Further research is needed to better understand how oxidative stress impacts animal performance and health as well as the optimum supplementation dose of XPC for newly received beef cattle

Effects of Original XPC on Newly Weaned Beef Steer Nutrient Digestibility and Response to a Vaccination Challenge

The study was designed to determine the effects of Diamond V Original XPC, a yeast fermentation product, in the diets of newly weaned beef steers on nutrient digestibility and response to a vaccination challenge. Although no overall performance benefit was noted, XPC improved total tract CP digestibility. Steers fed XPC at 14 g/d exhibited lesser concentrations of APP, greater DMI, and more efficient rumination post-vaccination. Further research is needed to determine the optimal supplementation rate of XPC to newly received beef cattle

Zinc supplementation and ractopamine hydrochloride impact gene expression of zinc transporters in finishing beef steers

Zinc is a trace mineral of interest for optimizing growth in feedlot cattle due to its roles in many physiological functions, including growth. Twenty-four Angus-cross steers (467 ± 13 kg) were used to assess the effects of supplemental Zn and ractopamine hydrochloride (RAC) on trace mineral concentrations and muscle gene expression. Four GrowSafe-equipped pens were randomly assigned to treatments (1 pen of six steers/treatment): 0 (CON), 60 (LOW), 120 (MED) or 180 (HI) mg supplemental Zn/kg DM (Availa-Zn, Zinpro). Dietary Zn treatments were initiated on d 0 and RAC supplementation (300 mg·steer·-1·d-1; Actogain45, Zoetis) began on d 53. Blood, liver and muscle (longissimus thoracis) samples were collected from all steers on d -4, 48, and 67. The LOW treatment was removed from gene expression analyses due to < 3 steers being represented for 14 of 22 genes. Data were analyzed using ProcMixed of SAS with the fixed effect of treatment and steer as the experimental unit; orthogonal linear and quadratic contrast statements were used to compare treatments. On d 48 and 67, there were linear and quadratic trends for plasma Zn to be greater in Zn-supplemented steers than CON (P ≤ 0.10). On d 48, there was a tendency for a quadratic decrease on the expression of SLC30A4 (P ≤ 0.07) but no other differences due to treatment. On d 67, several genes involved in Zn transport and storage (MTA1, SLC39A7, SLC39A8, SLC39A9, SLC39A10, SLC39A13) were decreased (P ≤ 0.08), suggesting increased growth influences intracellular Zn trafficking and demands