Relationships Among Temperament, Acute and Chronic Cortisol and Testosterone Concentrations, and Breeding Soundness During Performance Testing of Angus Bulls
The aim of this study was to examine relationships among temperament, endocrinology, and reproductive parameters of bulls enrolled in an 84-day performance test. Bulls exhibited physiological evidence of acclimation during the test as indicated by a reduction in hair cortisol concentration. In addition, the ability of the bulls to acclimate while residing at the testing center may have contributed to little differences observed during the breeding soundness examination portion of the performance test.
Effects of Pre-weaning Feed Supplementation and Total Versus Fenceline Weaning on the Physiology and Performance of Beef Steers
The hypothesis of this experiment was that a 1-week supplementation of the cow-calf pair with the palatable diet would be sufficient time to familiarize the calf to subsequent offering following weaning, thus reducing the acute stress response experienced by the calf following two different methods of separation from its dam. However, the results of the present study suggest that providing a high fiber supplement beginning 7 days prior to weaning may reduce body weight loss and temper the steers' acute stress response when weaned using total separation from their dam.
Does Prepartum Supplemental Feed Impact Beef Cattle Profitability Through Finishing?
Little is known about the impact of a supplemental prepartum feed ration for cows on the profitability of their calves. Therefore, we investigated the impact of animal characteristics and a supplemental prepartum feed program for cows on net returns to finished steers and the probability of a steer grading Choice or higher. Data were collected for 160 Tennessee steers that were finished in a feedlot. The supplemental prepartum feeding program decreased net returns of finished steers. Several animal characteristics were found to influence net returns of finished steers and the probability of a steer grading Choice or higher.
Protective Effect of Anti-SUAM Antibodies on Streptococcus Uberis Mastitis
In the present study, the effect of anti-recombinant Streptococcus uberis adhesion molecule (SUAM) antibodies against S. uberis intramammary infections (IMI) was evaluated using a passive protection model. These findings suggest that anti-rSUAM antibodies interfered with infection of mammary gland by S. uberis which might be through preventing adherence to and internalization into mammary gland cells, thus facilitating clearance of S. uberis, reducing colonization, and causing less IMI.
Combining Marandu Grass Grazing Height and Supplementation Level to Optimize Growth and Productivity of Yearling Bulls
Two experiments were conducted to determine the effects of grazing height and supple-mentation levels of Marandu pastures on average daily gain (ADG), gain per hectare (GPH)and methane (CH4) emissions during the wet season under continuous stocking by Neloreyearling bulls.
Microbial Community Profiles of the Jejunum from Steers Differing in Feed Efficiency
Research regarding the association between the microbial community and host feed efficiency in cattle has primarily focused on the rumen. However, the various microbial populations within the gastrointestinal tract as a whole are critical to the overall well-being of the host and need to be examined when determining the interplay between host and nonhost factors affecting feed efficiency.
Relationships Among Temperament Behavior, and Growth During Performance Testing of Bulls
Excitable cattle are dangerous to personnel and have reduced individual performance. The aim of this study was to 1) identify objective criteria for evaluating bull temperament and 2) examine relationships among temperament, behavior, and performance of bulls during an 84-d performance test.
Microbial Community Profiles of the Colon from Steers Differing in Feed Efficiency
Ruminal microbial fermentation plays an essential role in host nutrition, and as a result, the rumen microbiota have been a major focus of research examining bovine feed efficiency. Microbial communities within other sections of the gastrointestinal tract may also be important with regard to feed efficiency, since it is critical to the health and nutrition of the host.
Profitability of Beef and Biomass Production from Native Warm-Season Grasses in Tennessee
Native warm-season grasses (NWSGs) have demonstrated potential to reduce summer forage variability, and furthermore, there has been growing interest in the use of NWSGs as lignocellulosic biomass crops. The objective of this research was to determine if there was a difference in net returns for full-season summer grazing beef steers on three NWSGs.
Cecum Microbial Communities From Steers Differing in Feed Efficiency
Apart from the rumen, limited knowledge exists regarding the structure and function of bacterial communities within the gastrointestinal tract
and their association with beef cattle feed efficiency. The study identified cecal microbial associations with feed efficiency, ADG, and ADFI. This study suggests an association of the cecum microbial community with bovine feed efficiency at the 16S level.
Improving Efficiency of Production in Pasture- and Range-Based Beef and Dairy Systems
Continued viability of production systems using pasture- and range-based grazing systems requires more rapid adoption of innovative management practices and selection tools that increase profitability by optimizing grazing management and increasing reproductive performance.