Higher-Order Calculus of Variations on Time Scales

We prove a version of the Euler-Lagrange equations for certain problems of the calculus of variations on time scales with higher-order delta derivatives.Comment: Corrected minor typo

Impact of Intake on Methane Production in Growing Steers

A study was conducted to evaluate the impact that level of intake has on methane and carbon dioxide production by growing steers. Two treatments were evaluated that included ad-libitum intake compared to limit-fed steers. The ad-libitum fed cattle had greater gains, similar feed efficiency and produced more methane and carbon dioxide per day, while the limit fed cattle produced more methane and carbon dioxide per pound of intake than the ad-libitum fed cattle

Impact of Intake on Methane Production in Growing Steers

A study was conducted to evaluate the impact that level of intake has on methane and carbon dioxide production by growing steers. Two treatments were evaluated that included ad-libitum intake compared to limit-fed steers. The ad-libitum fed cattle had greater gains, similar feed efficiency and produced more methane and carbon dioxide per day, while the limit fed cattle produced more methane and carbon dioxide per pound of intake than the ad-libitum fed cattle

Evaluation of 0 or 300 mg of Optaflexx® on Growth Performance and Carcass Characteristics of Steers Fed to Different Degrees of Finish

A feedlot study evaluated the effects of ractopamine hydrochloride (Optaflexx®) dosage (0 or 300 mg/steer daily) and days on feed (118, 139, 160, 174 DOF) as a 2 × 3 + 1 factorial (steers fed 174 d were not fed Optaflexx) on performance of big yearlings. No interaction was observed between Optaflexx and days on feed. Feeding Optaflexx improved live final BW, carcass- adjusted ADG, carcass- adjusted feed conversion, and calculated yield grade. Increasing days on feed linearly increased live final BW, carcass-adjusted feed conversion, HCW, dressing percent, and marbling score but not ADG. Furthermore, a quadratic increase in LM area, 12th rib fat, and calculated yield grade was observed with days on feed. The response in added carcass weight due to feeding Optaflexx is the same with different lengths of time cattle are fed, and for large yearlings placed on feed

Comparison of Titanium® 5 PH- M versus Titanium® 5 plus NUPLURA® PH with the Presence or Absence of Monensin on Health and Performance of Newly Received Feedlot Calves Fed RAMP®

A receiving study was conducted to evaluate the effects of RAMP® with Rumensin® concentration (0 or 25.0 g/ton) given with one of two viral vaccinations (Titanium® 5 PH- M or Titanium® 5 plus NUPLURA® PH) on steer growth performance and morbidity. There were no significant vaccine by diet interactions observed. Neither vaccine treatment nor Rumensin® level affected intake, gain, or feed conversion. Vaccine type did not affect first pull (P = 0.19) or second pull morbidity rates (P = 0.52). These findings suggest that neither vaccine type nor Rumensin® concentration had any effect on steer growth performance or morbidity rate

Evaluation of Fractionated Distillers Grains (High Protein and Bran Plus Solubles) on Performance and Carcass Characteristics in Finishing Diets

A finishing study evaluated the effect of feeding a new, high protein distillers grains along with corn bran plus condensed distillers solubles compared to traditional wet distillers grains, traditional dry distillers grains and a corn-based control. Each byproduct replaced corn at 40% of the diet dry-matter. Intake was not affected by treatment; however gain and carcass weight were greater and feed conversion improved for high protein distillers and corn bran plus solubles than either type of traditional distillers grains or corn. Based on feed efficiency, the feeding values of high protein distillers grains and corn bran plus solubles are 121% and 125% that of corn, respectively. These new byproducts appear to be viable options for producers to utilize in finishing diets

Evaluation of Corn Bran Plus Solubles on Performance and Carcass Characteristics in Finishing Diets

A finishing study was conducted to determine the effect of feeding corn bran plus solubles, a new feed resulting from a pre-fermentation fiber removal process, compared to wet distillers grains plus solubles at two levels of inclusion (20% and 40% of diet DM). Intake increased with inclusion of byproduct, and steers fed 20% wet distillers had the greatest intakes numerically. Byproduct inclusion, regardless of type, increased daily gain over the corn-based control. Feed conversions were improved with increased inclusion of both Bran + Solubles and wet distillers, and both were superior to the control. Increased inclusion of both byproducts resulted in a linear increase in carcass weight. Feeding Bran+Solubles resulted in performance and carcass characteristics similar to wet distillers at both 20% and 40% inclusion

Effect of Revalor-XR and Revalor-XH on Heifer Performance and Carcass Characteristics

A feedlot study evaluated the effects of 4 implant strategies (Revalor-XR on day 1, Revalor-XH on day 1, Revalor-200 on day 1, and Revalor-200 on day 70) on growth performance and carcass characteristics of feedlot heifers compared to non-implanted heifers fed 198 days. Intake was not impacted by treatments. Implanted cattle had greater carcass-adjusted ADG and lower F:G compared to cattle that received no implant. Implanted treatments had significantly greater HCW, dressing percentages, and lower marbling scores compared to non-implanted cattle. Heifers implanted with Revalor-XR, Revalor-XH, and Revalor-200 on day 70 had larger LM area resulting in lower calculated yield grades compared to Revalor-200 administered on day 1 and control cattle. The response in gain, feed efficiency, and yield grade suggest that Revalor-XR, Revalor-XH, and Revalor-200 implanted on day 70 respond similarly when heifers are fed to similar days

Evaluation of Reimplant Window with Revalor-200 ® on Steer Performance and Carcass Characteristics

A feedlot study utilizing 800 crossbred steers (initial BW = 727 ± 55 lb) compared 5 different terminal implant (Revalor-200) times (160, 120, 100, 80, or 40 d prior to harvest) for steers fed 180 days on performance and carcass characteristics. All steers were implanted with Revalor-IS as an initial implant at trial initiation. Carcass-adjusted final BW, ADG, and F:G responded quadratically, with cattle implanted 80 to 120 d prior to harvest being the greatest. However, there was less than a 2% difference in performance between 120 and 80 days on terminal implant. Hot carcass weight responded quadratically, with no difference in fat thickness, rib eye area, marbling score, or calculated yield grade. When solved for the first derivative, all variables were maximized at 87 to 104 days on terminal implant when steers are fed for 180-d