J. J. Wagner

Evaluation of Saccharomyces cerevisiae fermentation product as an alternative to monensin on growth performance, cost of gain, and carcass characteristics of heavy-weight yearling beef steers

Two hundred fifty-two cross-bred yearling steers (406 ± 24 kg BW) were used in a completely randomized block design with a 2 × 2 factorial arrangement of treatments (7 pens/treatment) to evaluate the effects of dietary Saccharomyces cerevisiae fermentation product (SFP) and monensin (MON) on growth performance and carcass characteristics. Dietary treatments arranged as a 2 × 2 factorial were 1) with or without SFP and 2) with or without MON. Finishing diets contained 19.7% of DM as dried distillers grains with solubles. Both SFP and MON were added in the total mixed ration in place of an equal amount of cornmeal (DM basis; target intake = 2.8 g of SFP and 33 mg of MON/kg of dietary DM). Each treatment group was offered ad libitum access to a transition ration from d 1 to 8 and then to the finishing ration from d 9 to 125. Body weights were collected on d 0, 28, 56, 84, 110, and 125. Initial and final BW was an average of 2-d weights (d -1 and 0 and d 124 and 125, respectively). Steers were shipped for harvest on d 125. Overall ADG was decreased (P = 0.03) in steers supplemented with SFP, but final BW was similar among treatments. Feeding SFP was associated with lighter (P < 0.01) HCW and a greater (P = 0.01) number of carcasses grading USDA Choice. Twelfth rib fat thickness was not affected by SFP (P = 0.82) or MON (P = 0.35), but numerical decreases in 12th rib fat thickness among cattle receiving SFP or MON alone contributed to a tendency (P = 0.07) for greater 12 rib fat thickness when SFP and MON were provided. There was no effect of treatment on cost of gain (P ≥ 0.21). The effects of SFP in the current study may have been limited in heavy yearling steers due to consumption of a finishing diet containing 19.7% dried distillers grains with solubles.

A Meta-Analysis Evaluation of Feeding Melengestrol Acetate to Feedlot Heifers Implanted with Estradiol, Trenbolone Acetate, or the Combination of Estradiol and Trenbolone Acetate

Abstract Mixed models were used to study feeding melengestrol acetate (MGA) to feedlot heifers implanted with an estrogenic compound (EST), trenbolone acetate (TBA), or the combination of EST and TBA. One hundred one treatment means from 18 research trials were included in the analyses. Estrogenic implants increased DMI (p

The Effects of Trace Mineral Source on Performance and Health of Newly Received Steers and the Impact of Cobalt Concentration on Performance and Lipid Metabolism During the Finishing Phase123

Two hundred sixteen Angus crossbred steers (230 kg ± 3.6) purchased from sale barns were utilized to determine the impact of trace mineral source and concentration on performance, tissue metabolites, and lipid metabolism. Treatments during the 27-d receiving phase consisted of 1) inorganic trace mineral (125 mg CuSO4/d per head, 360 mg ZnSO4/d per head, 200 mg MnSO4/d per head, and 12.5 mg CoCO3/d per head) or 2) organic trace mineral (iso-amounts of Cu, Zn, Mn amino acid complexes, and Co glucoheptonate). On d 0 and 27, blood samples were collected from 3 steers per pen (pen = experimental unit). On d 28, steers were transitioned to a high concentrate finishing diet containing different concentrations of Co. Treatments during the finishing phase consisted of 1) control (no supplemental Co); 2) 0.10 mg Co/kg DM from cobalt glucoheptonate; and 3) 1.0 mg Co/kg DM from cobalt glucoheptonate. The same 3 steers per pen were bled on d 84 and 224 of the finishing phase. During the receiving phase, red blood cell superoxide dismutase activity was greater (P < 0.03) for organic- vs. inorganic-supplemented steers. During the finishing phase, overall ADG tended (P < 0.06) to be greater for steers receiving 1.0 mg Co/kg DM. Steers receiving 1.0 mg Co/kg DM had greater YG (P < 0.04) and back fat thickness (P < 0.04) than steers receiving 0.10 mg Co/kg DM. Serum, liver, and LM B12 concentrations increased (P < 0.04) as dietary Co concentration increased.

Predicting water intake by yearling feedlot steers

Data from 4 separate beef cattle feedlot experiments, which were conducted at the Southeast Colorado Research Center (SECRC) in Lamar, CO, in 2001, 2003, 2004, and 2007, were utilized in a retrospective longitudinal study investigating possible relationships between daily water consumption (WC), DMI, and weather variables. The data set consisted of 8,209 records from 2001, 2003, 2004, and 2007, with pen based daily WC (L•animal(-1)) and DMI measurements and calculated daily steer BW from April to October in each year. Daily weather data were obtained from the weather station located at Lamar Municipal Airport located approximately 1.9 km from SECRC. Data collected consisted of daily high, low, and mean temperature; high, low, and mean humidity; high, low, and mean sea level pressure; mean wind speed; total precipitation; and average daily wind direction (cosine of radians from due north). Univariate analysis demonstrated that the continuous variables of BW, humidity, and sea level pressure were negatively related (P < 0.0001), whereas DMI, temperature the previous day, daily temperature, change in temperature from the previous day, average wind speed, and the temperature-humidity index (THI) were positively related (P < 0.001) to daily WC. There was a trend (P < 0.06) for the cosine of wind direction (1 = due north and -1 = due south) to be negatively related to WC. The multivariate, parsimonious model predicting average daily WC included (P < 0.05) average humidity, average humidity squared, high temperature squared, high humidity squared, low temperature, low temperature squared, low humidity, average sea level pressure, average wind speed, average daily BW, high sea level pressure, low sea level pressure, high humidity, and low humidity. The generalized R(2) of the parsimonious multivariate model was 0.32. These results indicate that BW and numerous weather factors are related to WC by yearling feedlot steers. Dry matter intake had minimal impact on WC for yearling feedlot steers consuming steam-flaked corn-based high concentrate diets from mid-spring to early fall.

The Effects of ZinMet Brand Liquid Zinc Methionine on Feedlot Performance and Carcass Merit in Crossbred Yearling Steers1,2,3

The use of liquid zinc methionine for yearling steers was evaluated. In Exp. 1, a control (CON) treatment provided 15, 40, and 100 mg/kg (DM basis) of Cu, Mn, and Zn from inorganic sources, and an organic trace mineral (ORG) treatment provided 10, 20, and 40 mg/kg (DM basis) of Cu, Mn, and Zn from Cu betaine, Mn methionine, and Zn methionine, respectively. Finished BW, ADG, DMI, and feed efficiency were similar (P > 0.30) for CON and ORG treatments. In Exp. 2, a CON treatment provided 100 mg/kg DM supplemental Zn from Zn sulfate and an ORG treatment provided 40 mg/kg DM supplemental Zn from Zn methionine and 60 mg/kg DM supplemental Zn from Zn sulfate. Body weight was increased (P 0.58) for CON and ORG treatments. Average daily gain from d 1 through 34 was improved (P < 0.05) for the ORG treatment as compared with the CON treatment (1.70 vs. 1.55 kg/d per head, respectively). Carcass weight, dressing percentage, YG, QG, and liver abscess rate were similar for CON and ORG treatments for both experiments. These data indicate that overall feedlot performance and carcass merit were similar for yearling steers fed CON and ORG trace mineral sources.

Temperament can be an indicator of feedlot performance and carcass merit in beef cattle

Introduction Cattle producers historically have selected for docile temperaments simply for management convenience because calmer animals are conducive to safe environments for their peers as well as their handlers. As many producers would acknowledge, however, there seems to be a relationship between temperament and cattle health, and calmer cattle tend to frequent the working chute for treatment of disease less often.

Case Study: The Effects of Severe Winter Weather on Net Energy for Maintenance Required by Yearling Steers

Severe winter storms in southeast Colorado in December of 2006 and January 2007 resulted in severe economic losses for the cattle feeding industry. Two hundred fourteen steers were weighed on December 26, 2006, and average BW (minus 4% pencil shrink) was 558 kg ± 21.7. Over the following 58-d period there was a 7.0% death loss and ADG was −0.13 kg ± 0.21. Average steer BW (minus 4% pencil shrink) was 550 kg ±18.7 on February 22, 2007. Total DM delivered was 53,436.7 kg and average NEm concentration in the diet was 2.263 Mcal/kg DM. Daily DMI averaged 9.67 kg/d per head. Average shrunk BW (SBW) was 554.1 kg and average empty body weight (497.7 kg), empty body gain (−0.00686 kg/d), and retained energy (−0.0283 Mcal/d) were calculated from NRC (2000) equations. The required NEm was 21.9176 Mcal/d per head or 0.1919 Mcal/kg of SBW0.75 These data indicate that NEm required during and in the aftermath of a major winter weather event may be 2.5 fold higher than NEm required (0.077 × SBW0.75) under thermal neutral conditions. Calculations of lower critical temperature and external insulation indicate that the insulation value of the hair coat may have been destroyed by the moisture, mud, and snow following the storm.

Genetic parameters estimated at receiving for circulating cortisol, immunoglobulin G, interleukin 8, and incidence of bovine respiratory disease in feedlot beef steers.

ABSTRACT Bovine respiratory disease complex (i.e., shipping fever and bacterial bronchopneumonia) is a multifaceted respiratory illness influenced by numerous environmental factors and microorganisms. Bovine respiratory disease (BRD) is just one component of BRD complex. Because BRD is moderately heritable, it may be possible to reduce the incidence of BRD through genetic selection. The objectives of this study were to determine the heritability and associative genetic relationships among immune system traits (i.e., cortisol, total IgG, IgG isotypes, and IL-8) in cattle monitored for BRD incidence. At an average of 83 d after weaning (219 d age and mean = 221.7 kg [SD 4.34]), crossbred Bos taurus steer calves (n = 2,869) were received at a commercial feedlot in southeastern Colorado over a 2-yr period. At receiving, jugular blood samples were collected at 212 (yr 1) and 226 d (yr 2) of age for immune trait analyses. The BRD phenotype was defined as a binomial variable (0 = no and 1 = yes) and compared with immune system traits measured at receiving (prior to illness onset). An animal identified as BRD positive exhibited ≥ 2 clinical signs (i.e., eye or nasal discharge, cough, lethargy, rapid breathing, acute interstitial pneumonia, or acute upper respiratory syndrome and/or a rectal temperature > 39.7°C). Heritability and genetic correlation estimates for categorical variable BRD, cortisol, IgG, IgG1, IgG2, and IL-8 were estimated from a sire model using ASREML. Heritability estimates were low to moderate for BRD (0.17 ± 0.08), cortisol (0.13 ± 0.05), IgG (0.15 ± 0.05), IgG1 (0.11 ± 0.05), IgG2 (0.24 ± 0.06), and IL-8 (0.30 ± 0.06). A moderate negative genetic correlation was determined between BRD and cortisol (rg = −0.19 ± 0.32). Moderate positive correlations were found between BRD with IgG (0.42 ± 0.28), IgG1 (0.36 ± 0.32), and IL-8 (rg = 0.26 ± 0.26). Variation in the BRD phenotype and immune system traits suggested herd health improvement may be achieved through genetic selection.

High-dose anabolic implants are not all the same for growth and carcass traits of feedlot steers: a meta-analysis.

A meta-analysis of studies evaluating feedlot steer implant programs was conducted to evaluate the differential effects of anabolic implant dosage on feedlot performance and carcass traits. The effect sizes of the implant dosage of interest vs. negative controls and vs. other implant dosages on various dependent variables (ADG, F:G, DMI, dressing percentage [DP], HCW, yield grade, percentage Choice or higher, and marbling score) were calculated. Treatments used for comparisons included no implant, EST (20 mg estradiol benzoate + 200 mg progesterone, 36 mg zeranol, or 72 mg zeranol), ET120 (24 mg estradiol 17β + 120 mg trenbolone acetate [TBA]), and ET200 (28 mg estradiol benzoate + 200 mg TBA or 20 mg estradiol-17β + 200 mg TBA). In the first analysis, the 3 implant dosages were compared to negative control. A second analysis was conducted to compare ET120 vs. ET200 using only studies that included a direct comparison of these 2 dosages. The number of studies included in the analysis for each implant dosage and response variable ranged from 34 to 7. A mixed model was used to evaluate individual implant treatments; implant dosage was a fixed effect, and individual study was included as a random effect. All dosages had greater ADG, DMI, and HCW and lower F:G, percentage Choice, and marbling score vs. negative controls (P < 0.05) In the second direct comparison analysis, ET200 tended to have greater ADG (P = 0.10) and HCW (P = 0.07) and had lower F:G (P < 0.01) and percentage of carcasses grading Choice or greater (P < 0.01) vs. ET120. Differences in HCW between ET120 and ET200 diminished numerically with increasing days of implant activity (P < 0.01). All dosages of implants evaluated herein increased performance and decreased quality grade vs. negative controls. Combination implants containing estrogen (E) and 200 mg TBA have greater potency for growth promotion than implants containing E+120 mg TBA resulting in slightly greater performance.

The Impact of Trace Mineral Source, Water Quality, and Short-Term Choline Supplementation on Performance and Carcass Characteristics of Finishing Steers12

ABSTRACT A total of 288 yearling steers (315.2xa0±xa03.7xa0kg) were used to determine the effects of trace mineral source, water quality, and short-term choline supplementation on feedlot performance and carcass characteristics. Trace mineral treatments consisted of 1) a control, namely, 15xa0mg Cu/kg DM, 20xa0mg Mn/kg DM, and 45xa0mg Zn/kg DM supplemental trace minerals in inorganic form; and 2) organic (proteinate form) iso-concentrations to the inorganic trace minerals composed of 50% organic and 50% inorganic trace minerals. Water treatments consisted of 1) a blend of reverse-osmosis (RO) water and well water (1,072.4xa0mg sulfate/L) and 2) well water (2,377.5xa0mg sulfate/L). At 29 d before slaughter, 4 pens of steers per trace mineralxa0×xa0water treatment combination were supplemented with choline at a rate of 20xa0g of rumen-protected choline/steer daily, and the remaining 4 pens served as the controls (no supplemental rumenprotected choline). There were no effects of trace mineral source, water quality, or interactions with feeding period for BW, ADG, DMI, or G:F. Initial and final BW, ADG, DMI, and G:F were similar across trace mineral and water treatments. Choline supplementation for only the last 29 d on feed did not affect performance. Morbidity, mortality, and percentage of retreated cattle were similar across trace mineral and water treatments. There was a trace mineralxa0×xa0water quality interaction (P