T.L. Stanton

Effects of Trace Mineral Supplementation on Cow-Calf Performance, Reproduction, and Immune Function

Abstract Three-hundred Angus cows were used in a randomized design to evaluate trace mineral supplementation over a 209-d trial on cow and calf performance, liver trace mineral content, and immune function. Treatments included the following supplemental trace minerals: 1) inorganic trace minerals—low level; 2) inorganic trace minerals—high level; and 3) organic trace minerals—high level. Cows fed the high level of inorganic trace minerals lost more weight (P

Effect of Source and Amount of Zinc, Copper, Manganese, and Cobalt Fed to Stressed Heifers on Feedlot Performance and Immune Function

One hundred and five crossbred heifer calves (208.6 kg ± 2.46) were used in two randomized block design studies to evaluate the effect of source and amount of Zn, Mn, Cu, and Co fed following weaning and transport stress on performance and immune response. Cattle were fed a basal diet that was supplemented with either: 1) inorganic trace minerals consisting of 106 ppm Zn from ZnO, 58 ppm Mn from MnO, 37 ppm Cu from CuSO4, and 7 ppm Co from CoCO3 (1× amount), or 2) organic element complexes fed isoelemental to inorganic trace element amounts (1×), providing Zn from Zn methionine (ZnMet), Mn from Mn methionine (MnMet), Cu from Cu lysine (CuLys), and Co from Co glucoheptonate (CoGlu), or 3) organic element complexes supplemented at 3× for the first 14 d posttransport; 318 ppm Zn from ZnMet, 174 ppm Mn from MnMet, 111 ppm Cu from CuLys, and 21 ppm Co from CoGlu, then reduced to the 1× supplement amount for the remaining period of the 42-d experiment (3×/1×). No differences were observed among treatments in calf DMI, ADG, or FE over the 42 d trial. There were, however, increases (P<0.01) in calf secondary PI-3 antibody titer response at 14 and 28 d postvaccination. Skin swelling response at 21 d posttransport and at 12, 24, and 48 h postinjection to intradermal PHA was better with feeding organic trace elements at the 3×/1× concentration than either the organic 1× or the inorganic 1× treatments. Feeding calves 1× organic trace elements improved antibody titer response to IBRV vaccination at 14 (P<0.01) and 28 (P<0.05) d compared to the calves receiving the 1× inorganic treatment. The calves fed organic 3×/1× had a 17.2% reduction (P<0.05) in incidence of respiratory disease when compared to the other treatments. In this trial, the feeding elevated organic minerals showed significant improvements in primary and secondary humoral, and cell-mediated immunity compared to the feeding of inorganic sources.

Effects of Lifetime Copper, Zinc, and Manganese Supplementation and Source on Performance, Mineral Status, Immunity, and Carcass Characteristics of Feedlot Cattle12

Two calf crops (n = 140, yr 1; n = 130, yr 2) from the same cowherd were used to evaluate the effects of lifetime Cu, Zn, and Mn supplementation and source on performance, status, immunity, and carcass traits of feedlot cattle. Dams were supplemented with trace mineral treatments from approximately 80 d pre-calving through 120 d post-calving. Treatments included 1) control (no supplemental Cu, Zn, or Mn), 2) organic (ORG; 50% organic and 50% inorganic Cu, Zn, and Mn), or 3) inorganic (ING; 100% inorganic CuSO4, ZnSO4, and MnSO4) trace minerals. In the feedlot, calves were maintained on the same treatments, except that ORG contained 33% organic and 67% inorganic Cu, Zn, and Mn. Cattle received a growing diet for 56 d and a finishing diet for 140 d (yr 1) and 145 or 181 d (yr 2) prior to harvest. There was a tendency for a growing-phase year × treatment interaction (P=0.10), and a finishing-phase year × treatment interaction was present (P<0.04) for BW gain to feed ratio (G:F). In yr 1, G:F was greater (P<0.05) in ORG cattle than in ING cattle during both feeding phases; non-supplemented controls had a greater (P<0.01) finishing phase G:F than did supplemented cattle. Supplemented cattle had greater (P<0.01) liver Cu concentrations than non-supplemented controls throughout both feeding phases, and liver Mn concentrations were greater (P<0.02) in supplemented cattle than in non-supplemented controls at the end of the finishing phase.

Effects of Concentration and Source of Trace Minerals on Performance, Immunity, Mineral and Lipid Metabolism, and Carcass Characteristics of Beef Steers

Abstract Two hundred seventy-nine steers were blocked by initial BW, stratified by estimated breed, and randomly assigned to pens and treatments within weight replication. Mineral treatments administered during the receiving phase consisted of Cu, Zn, Mn, and Co administered at the following levels: 1) two times the NRC (1996) recommendation from amino acid complex Availa-4® (Zinpro, Eden Prairie, MN); 2) at the NRC recommendation from Availa-4®, 3) three times the NRC recommendation from inorganic minerals, or 4) six times the NRC recommendation from inorganic minerals. Steers were gradually switched from a moderate to high concentrate corn-alfalfa diet. Finishing phase mineral treatments consisted of 1) mineral treatment from Availa-4® fed at NRC recommendations, 2) mineral treatment from Availa-4® fed at one and one-half times the NRC recommendation, 3) minerals from inorganic sulfate sources fed at one and one-half times the NRC recommendation, or 4) minerals from inorganic sulfate sources fed at three times the NRC recommendation. Eight pens from each treatment were harvested after being fed for a period of 198 or 230 d. Average daily feed intake was reduced (P IBR ) was not different (P>0.05) between treatments. Steers on the organic mineral treatment at one and one-half times the NRC recommendation had greater (P

Trace Mineral Supplementation in the Presence of Antagonists on Growth Performance, Health, and Carcass Characteristics of Transport-Stressed Calves

Crossbred steer calves (n = 64) were used in a 2 × 2 factorial arrangement to evaluate two levels of organic trace minerals and two levels of inorganic trace minerals. Calves were fed 28 d on the ranch in two pens of eight head per treatment before a simulated transport stress. After being loaded, hauled 129 km, unloaded with an overnight stand without feed and water, and reloaded, they were shipped to the Colorado State University (CSU) research feedyard in Fort Collins and placed in 64 individual pens. Calves fed the organic low level and inorganic high level trace minerals gained better (P<0.05) the first 28 d than did calves fed the organic high level or inorganic low level trace minerals. Overall growth performance was not influenced by trace mineral types or levels. Longissimus area was greater (P<0.05) for calves fed the low level organic trace minerals compared with that for calves fed the low level inorganic trace minerals. Eosinophils (d 28) were higher (P<0.05) for calves fed the organic high level trace minerals compared with calves fed inorganic low level trace minerals. Infectious bovine rhinotracheitis (IBR) and parainfluenza (PI3) titers were not influenced by trace minerals. Red blood cells and packed cell volume were higher (P<0.05) for calves fed low level trace minerals regardless of trace mineral type. Liver Co was increased (P<0.05) at the 28-d sampling when inorganic trace minerals were fed. Liver Co was highest (P<0.05) at the 168- d sampling for calves fed low level inorganic trace minerals followed by calves fed organic high level trace minerals. Liver Fe was lower (P<0.05) in calves at the d-168 sampling when organic trace minerals were fed. Liver Zn was elevated (P<0.05) by d 28 by feeding the inorganic low level trace minerals, and by d-168, liver Zn was higher (P<0.05) for calves fed the low levels of trace minerals. Initial growth performance was maintained by either supplementing organic trace minerals or elevating dietary inorganic trace minerals when confronted with high dietary Fe, S, or Mo.

Effect of Roughage Source in Whole Shelled Corn Diets on Feedlot Performance and Digesta Kinetics of Cattle

Two trials (feedlot and metabolism) were conducted to evaluate the effects of roughage source in whole shelled corn (WSC)-based diets fed to beef steers. In the feedlot trial, 296 mixed-breed steers (avg. BW 317 kg) were fed diets consisting of either 6% alfalfa hay (AH), wheat straw (WS), or ammoniated wheat straw (AWS) and 8% corn silage (CS) of diet DM as the roughage source; the remaining portions were WSC and a pelleted protein supplement. Roughage source had little effect (P>0.30) on ADG and feed efficiency over the 134-d feeding period. Feed consumption, however, was lower (P<0.05) for steers fed the WS diet than for the other three diets. Four ruminally and duodenally cannulated beef steers (avg. BW 469 kg) were used in a 4 × 4 Latin square metabolism trial. Ruminal pH was similar for steers fed the CS, WS, and AWS diets, but was higher (P<0.10) for steers fed the AH diet. Total VFA concentration was highly correlated with ruminal (pHR=−0.87) and was lower (P<0.05) in steers fed the AH diet than in those fed the other three diets. Ruminal and total tract digestion of OM, starch, and N, estimated using chromic oxide as a marker, were not affected by roughage source. Results suggest that WS and AWS can replace AH or CS as a roughage source in WSC finishing diets without adversely affecting feedlot performance and (or) site, extent and kinetics of whole corn digestion.

Phosphorus and Vitamin D in Beef Finishing Diets

Abstract Two hundred eighty-three steer calves (mean BW = 290 ± 6 kg) were used to evaluate the effects of feeding two levels each of phosphorus and vitamin D on growth performance and carcass characteristics. The experimental design was a 2 × 2 factorial arrangement of a randomized block design with approximately 71 steers per treatment. Steers were randomly assigned to one of four treatment groups. Each group consisted of six pens of 11 or 12 steers each. The four treatments were 1) Low P:low vitamin D (0.24% and 0 IU/kg, respectively) 2) Low P:high vitamin D (0.24% and 5,364 IU/ kg, respectively) 3) High P:low vitamin D (0.35% and 0 IU/kg, respectively) and 4) High P:high vitamin D (0.35% and 5,364 IU/kg, respectively). Starting diets contained 65% whole corn and increased to a final 89.9% whole corn finishing diet over a 4r-wk period. Overall DMI, ADG, and feed efficiency were not affected by supplementing with phosphorus and/or vitamin D in finishing diets. Off-test BW and hot carcass weight were numerically heavier for cattle supplemented with P and vitamin D. Supplementing P and/ or vitamin D to finishing calves had no significant benefit on growth performance or carcass characteristics.

Effect of Pre- and Post-Shipment Trace Mineral Type and Level on Subsequent Feedyard Performance and Immune Function

Abstract Sixty-nine Angus steers were used in a randomized block design to evaluate three treatments 28 d prior to and through 56 d post-shipment. Treatments included 1) control: low level of supplemental trace minerals; 2) inorganic: supplemental trace minerals from Zn sulfate, Mn sulfate, Cu sulfate, and Co carbonate at isomineral levels to treatment 3; and 3) organic: supplemental trace minerals were provided by Zn, Cu, and Mn amino acid complexes. The Zn, Cu, Mn, and Co dietary levels were below 1996 NRC requirements for treatment 1 and exceeded those levels for treatments 2 and 3. Feeding organic trace minerals tended to improve feed efficiency pre-shipment while on the ranch. Post-shipment feed intake and average daily gain were not affected by treatment. However, feeding the high level of inorganic trace minerals improved ( P P P P >0.05) with higher levels of supplemental trace minerals.

Effects of Copper and Zinc Source on Performance, Carcass Characteristics, and Lipid Metabolism in Finishing Steers123

An experiment was conducted to determine the effects of Cu and Zn source on performance, trace mineral status, lipid metabolism, and carcass quality of finishing steers. In the study, 195 steers were blocked by origin, stratified by BW, and sorted into 24 pens. Pens within blocks were then randomly assigned to treatments in a 2 × 2 factorial arrangement. Factors were 10 mg of Cu/kg of dietary DM from CuSO4 or 10 mg of Cu/kg of dietary DM from organic Cu and 90 mg of Zn/kg of dietary DM from ZnSO4 or 36 mg of Zn/kg of dietary DM from organic Zn with 54 mg of Zn/kg of DM from ZnSO4. Steers were fed a high concentrate finishing diet until they reached an approximate BW of 580 kg. Diets were fed once daily in the morning to allow ad libitum access to feed throughout the day. Daily feed offerings were recorded and feed refusal was measured every 28 d. Body weights were recorded for each steer and blood samples were collected from 3 steers per pen every 28 d. Three weeks prior to slaughter, subcutaneous adipose tissue biopsies were taken from 1 steer per pen. Postharvest longissimus dorsi muscle samples were collected and evaluated for fatty acid composition. There were no Cu or Zn main effects or Cu × Zn interactions for ADG, DMI, or feed efficiency. The effect of Cu or Zn source was similar across treatments for hot carcass weight, dressing percent, rib eye area, subcutaneous fat thickness, kidney, pelvic, and heart fat, and marbling score. There was a Zn effect for calculated yield grade. Steers receiving organic Zn had a lesser (P = 0.03) calculated yield grade than steers receiving inorganic Zn. Serum cholesterol, plasma Cu and Zn concentrations, fatty acid composition of longissimus muscle and subcutaneous fatty acid synthase activity were similar across treatments. Results from this study indicate that trace mineral source had little influence on performance, carcass characteristics, and lipid metabolism.

Effects of Salt Level on Growth Performance, Carcass Characteristics, and Manure Salinity of Finishing Beef Steers

Abstract Two hundred ninety-six British and Charolais crossbred beef steers (average BW = 305 ± 20.4 kg) were fed for 163 d at the Eastern Colorado Research Center in a randomized block design to evaluate effects of four dietary levels of salt (NaCl) on growth performance, cost of gain, morbidity/mortality, carcass characteristics and manure nutrient content. Calves were stratified by breed, randomized by BW, and assigned to one of four supplemental NaCl treatments (6 pens per treatment; containing of 11 to 13 head/ pen): 0.0, 0.125, 0.25% or block salt. Average daily feed intake, ADG, feed efficiency, and feed cost of BW gain were not affected (P>0.05) by dietary salt level. Neither mortality nor morbidity was influenced by dietary salt level. Dressing percent and hot carcass weight tended to decrease (P=0.08) linearly as salt supplementation increased. As dietary NaCl increased, concentrations of Na and Mg increased linearly (P