T. L. Mader

Evaluation of Dry Distillers Grains Plus Solubles Inclusion on Performance and Economics of Finishing Beef Steers1

A 167-d feedlot study was conducted to evaluate feeding increasing levels of dry distillers grains plus solubles (DDGS) to finishing cattle and the impact on performance and profitability. Crossbred steer calves (n = 240, BW = 306 ± 24.5 kg) were used in 30 pens with dietary treatments of 0, 10, 20, 30, and 40% DDGS dietary inclusion (DM basis). Quadratic relationships (P 0.15) by DDGS level, but G:F tended to be quadratic (P = 0.10) as 20% DM inclusion had the greatest value, although steers fed all levels of DDGS had numerically greater G:F compared with steers fed no DDGS. Carcass characteristics, other than hot carcass weight, were not affected by DDGS treatment. Energy value of DDGS at 10 to 40% dietary inclusion resulted in a quadratic trend (P = 0.10) and remained above corn, with the highest values at 10 and 20% inclusion averaging 127% of corn. When DDGS was priced equally to corn, all levels of DDGS from 10 to 40% inclusion resulted in higher profits compared with a dry-rolled corn based diet regardless of corn price. The greatest returns were observed when cattle were fed 20% DDGS. These data indicate that DDGS can be fed up to 40% DM to improve cattle performance and result in economic profits, with optimum levels at 20 to 30% diet DM.

Case Study: Tympanic Temperature and Behavior Associated with Moving Feedlot Cattle1

Body temperature is often used as an indicator of animal health status. In a series of handling experiments, tympanic temperatures (TT) were obtained in unrestrained feedlot cattle. In a January experiment (BW = 531 ± 54 kg), TT were increased (P<0.05) 0.65°C and 0.58°C by moving cattle 600 m in morning and afternoon, respectively. Moving cattle (BW = 456 ± 67 kg) 150 and 600 m in August elevated TT by 0.30°C and 0.67°C, respectively. Moving cattle (BW = 415 ± 62 kg) 900 m in June elevated (P<0.05) TT by 0.78°C. Recovery TT was determined to be the time peak TT declined to levels equal to or below control (non-moved cattle) TT. Recovery times averaged 3.5 h in the winter, but ranged from <1 h to approximately 2 h in the spring and summer experiments. Moving cattle decreased (P<0.05) feed intake by approximately 1 kg/d for up to 48 h after moving was completed. Moving cattle in the morning also decreased (P<0.05) the number of animals resting in the afternoon (1400 h; Experiment 3) and increased (P<0.05) the number of animals panting throughout the day (1100 and 1400 h; Experiment 4). Effects of cattle movement on body temperature may need to be taken into account when evaluating animal health status. Conclusions based on these data would be most applicable for feedlot cattle exposed to warm and thermoneutral environmental conditions.

Heat load management for feedlot cattle

Altering the microclimate by providing protection from the environment is one of the most useful tools helping animals cope with climatic conditions. For most feedlot cattle, facilities and management programs do not need to eliminate environmental stress completely, but rather minimize the severity of the environmental challenge and aid the animal in adapting to it. In addition to facility changes, dietary manipulation may also be beneficial for feedlot cattle challenged by environmental conditions. Studies conducted at the University of Nebraska demonstrate that programmed feeding systems significantly lower body temperatures during periods of heat stress. Programmed feeding systems involve management of feed intake pattern so as to eliminate or minimize simultaneous occurrence of peak metabolic and climatic heat loads. Tympanic temperatures were measured via thermistors placed in the ear canal and attached to data loggers. Cattle managed on programmed feeding systems for three to six weeks, maintained equal or lower tympanic temperature when compared with cattle fed ad libitum. The reduced tympanic temperature is likely due to a reduction in metabolic rate and a concurrent reduction in metabolic heat load. Greater long-term reductions in tympanic temperature likely occur if the cattle are on the programs for 1 to 2 weeks prior to the heat wave. Utilizing programmed feeding systems from late-June to early-August would appear to be sufficient to cover most heat waves.

Limit-Fed High-Energy Growing Programs for Feedlot Steers1

Abstract In two feeding trials, steers limit-fed high-energy growing diets were found to be more ( P P P P P P P