Analysis of the Gut Bacterial Communities in Beef Cattle and Their Association with Feed Intake, Growth, and Efficiency
This review addresses recent research regarding the bacterial communities along the gastrointestinal tract of beef cattle; their association with ADG, ADFI, and feed efficiency; and the potential implications for beef production.
Circulating Beta-hydroxybutyrate Concentration may be a Predictive Measurement for Young Cows that have a Greater Probability to Conceive at a Fixed-time Artificial Insemination
Timing of conception, which has been indicated to be negatively influenced by metabolic dysfunctions, can influence lifetime productivity within the cow herd. Therefore, our objective was to analyze the association of milk production, serum metabolites as an indicator of nutrient status, cow BW and BW change, and calf BW with timing of pregnancy in 183 spring-calving beef cows.
Rumen-protected Arginine Alters Blood Flow Parameters and Luteinizing Hormone Concentration in Cyclic Beef Cows Consuming Toxic Endophyte-infected Tall Fescue Seed
The objective of this study was to determine the effect of rumen-protected arginine on median caudal artery blood flow and LH dynamics in cows fed toxic endophyte-infected tall fescue seed. Supplementing rumen-protected Arg to cows consuming toxic endophyte- infected fescue seed has the potential to increase reproductive performance and peripheral blood flow.
High Milk Production Decreases Cow-Calf Productivity Within a Highly Available Feed Resource Environment
The beef cattle industry tends to focus on selecting production traits with the purpose of maximizing cow-calf performance. One such trait is milking ability, which is considered the primary influence on weaning weight of the calf. Therefore, the objective of this study was to determine the effect of actual milk yield on reproductive performance, circulating blood metabolites, and calf performance in beef cows in the Southeastern US.
Drivers of Grazing Livestock Efficiency: How Physiology, Metabolism, Experience and Adaptability Influence Productivity
To achieve this metabolic adaptability or flexibility, beef cows need to be suited to their environment and have the ability to acclimate to environmental changes. The purpose of this proceedings paper is to identify and describe factors that influence range cow efficiency and ultimately contributes to the sustainability (both from a productivity and economic view point) of range cows in extensive enterprises.
Probability of Receiving an Indemnity Payment from Feeder Cattle Livestock Risk Protection Insurance
Livestock risk protection (LRP) insurance is a price risk management tool available to cattle producers; however, producers have been hesitant to adopt LRP. The objective of the study was to determine the monthly feeder cattle LRP contract coverage level and length maximizing the probability of the LRP net price being greater than the CME Feeder Cattle Index (CME FCI) price. The CME FCI prices were higher than the LRP net price for the majority of the contract lengths and coverage levels. Several coverage lengths and levels provided similar price protection, and there was no consistent preferred coverage length and level.
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.