Impact of luteal blood perfusion and expression of estrus on pregnancy rates of Bos taurus embryo recipients exposed to fixed-time embryo transfer.

This study evaluated the impact of luteal blood perfusion (BP) and expression of estrus on pregnancy rates of Bos taurus embryo recipients exposed to fixed-timed embryo transfer (FTET) using a gonadotropin-releasing hormone (GnRH)- and progesterone-based ovulation synchronization protocol. Postpartum beef cows (n = 746) were exposed to a GnRH/progesterone-based ovulation synchronization protocol. Luteal morphometry and BP were assessed using color Doppler ultrasonography 9 days after CIDR removal concurrently with FTET.

Effects of maternal Cu, Mn, and Zn supplementation from different sources on physiological and productive responses of cows and their offspring.

Seventy-two nonlactating, pregnant Angus cows (initial body weight [BW] = 637 ± 13 kg; body condition score [BCS] = 5.5 ± 0.07 yr; and age = 6.

Replacing sulfate with hydroxychloride sources of trace minerals modulated the growth performance and plasma indicators of inflammation and energy metabolism in beef heifers during periods of feed restriction and adaptation to a high-starch diet.

This study evaluated the effects of different sources (sulfate vs. hydroxychloride) of Cu, Mn, and Zn during feed restriction and a high-starch diet on heifer growth performance. On day 0, Nelore heifers (n = 40) were stratified by body weight (BW = 238 ± 38 kg) and age (21 ± 1 mo), and individually allocated into 1 of the 40 drylot pens.

Administering the maternal bovine appeasing substance improves overall productivity and health in high-risk cattle during a 60-d feedlot receiving period.

This experiment evaluated health, physiological, and performance responses of high-risk cattle administered the maternal bovine appeasing substance (mBAS) during feedlot receiving. Angus-influenced, newly weaned male calves (n = 120) were purchased from an auction facility. Calves arrived at the research feedyard on day -1 and body weight (BW) was recorded upon arrival (199 ± 1 kg).

Supplementing a Bacillus-based probiotic to high-risk stocker cattle.

This experiment evaluated the performance, health, and physiological responses of high-risk steers receiving a Bacillus-based probiotic during a 90-d grazing period. A total of 240 Angus-influenced steers were used in this experiment that was replicated over 2 yr (120 steers/year). Each year, steers were obtained from an auction yard and transported to the experimental facility (120 km).

Influence of differing levels of concentrate on circulating cytokine concentrations in beef heifers.

Components of the immune system (e.g., cytokines and chemokines) can influence reproductive efficiency.

Effects of a moderate exercise regimen on development and puberty attainment of beef heifers reared in drylots at a high stocking density.

This experiment evaluated growth, physiological responses, and puberty attainment in beef heifers reared in drylots with a high stocking density, and provided or not with a moderate exercise regimen. A total of 180 heifers (75% Angus × 25% Brahman) were used in this experiment replicated over 2 yr. Each year, 90 heifers were ranked by age (264 ± 1 d) and body weight (BW on day -3; 200 ± 2 kg) on day 0, and assigned to a) one of six drylot pens (10 × 14 m pens; 10 heifers per pen) with a stocking density of 14 m2/heifer (DENS), or b) one of three pastures (2-ha pastures; 10 heifers per pasture) with a stocking density of 2,000 m2/heifer (CON).

Supplementing narasin or monensin to control coccidiosis in naturally infected calves.

This experiment compared narasin and monensin as anticoccidials for calves naturally infected with spp. Twenty-four weaned, non-castrated male calves ( ×  cross) were assigned to this experiment (days -8 to 42). All calves were infected by spp.

Comparison of physiological markers, behavior monitoring, and clinical illness scoring as indicators of an inflammatory response in beef cattle.

Clinical illness (CI) scoring using visual observation is the most widely applied method of detecting respiratory disease in cattle but has limited effectiveness in practice. In contrast, body-mounted sensor technology effectively facilitates disease detection. To evaluate whether a combination of movement behavior and CI scoring is effective for disease detection, cattle were vaccinated to induce a temporary inflammatory immune response.

Dogs' ability to detect an inflammatory immune response in cattle via olfaction.

Introduction: Canine olfaction is a potential means for detection of respiratory disease in beef cattle. In a prior study, two dogs were trained to discriminate between nasal swabs from healthy cattle and cattle that developed Bovine Respiratory Disease. Dogs had some ability to identify samples from BRD-affected cattle, but results were ambiguous.

Maternal pre- and postpartum supplementation of a Bacillus-based DFM enhanced cow and calf performance.

This study evaluated the effects of maternal supplementation of a Bacillus-based direct-fed microbial (DFM) on the physiology and growth performance of Bos indicus-influenced cow-calf pairs. On day 0 (~139 d before expected calving date), 72 fall-calving, Brangus crossbred beef heifers (20 to 22 mo of age) pregnant with first offspring were stratified by their initial body weight (BW; 431 ± 31 kg) and body condition score (BCS; 6.0 ± 0.

Administering the maternal appeasing substance before slaughter to improve carcass characteristics of finishing cattle.

Two experiments evaluated carcass characteristics of finishing steers administered the maternal bovine appeasing substance () prior to slaughter. In Exp. 1, 954 Angus-influenced finishing steers housed in 6 original pens were used.

Effects of supplementing direct-fed microbials on health and growth of preweaning Gyr × Holstein dairy calves.

This study aimed to evaluate the effects of direct-fed microbials (DFM) on health and growth responses of preweaning Bos indicus × Bos taurus (Gyr × Holstein) crossbred calves. Ninety newborn heifer calves (initial BW of 35 ± 4.0 kg) were used.

An updated meta-analysis of the anti-methanogenic effects of monensin in beef cattle.

Meta-analyses were performed to quantitatively summarize the effects of monensin on in vivo methane (CH4) production in beef cattle, and differentiate these outcomes according to dietary management, dose of monensin, and length of monensin supplementation. Data from 11 manuscripts describing 20 individual studies were used, and CH4 was converted to g/d when required. Studies were classified according to dose of monensin (mg/kg of diet dry matter), length of monensin supplementation prior to the last CH4 measurement, feeding management (ad libitum vs.

Consider the Source: The Impact of Social Mixing on Drylot Housed Steer Behavior and Productivity.

Cattle are a social species in which social mixing can induce physical and psychosocial stress; however, the impact of social mixing on cattle welfare is unknown. Two different sources of genetically similar Angus crossbred steers were transported to the same feedlot and assigned to a pen where they were either socially mixed or housed with individuals from their source herds. Social mixing did not impact average daily gains in pens, feed intake, or feed efficiency; pens of socially mixed steers were more active.

Impacts of learning experiences within an online extension initiative on application of research-based principles by beef stakeholders.

The objective of this study was to evaluate, characterize and quantify the learning experiences and subsequent application of research-based technologies by beef producers upon conclusion of an online extension certification program (44 Farms International Beef Cattle Academy, IBCA). Upon conclusion of the program, paricipants were invited to complete a structured interview. Interview transcripts ( = 19) were coded, categorized, and merged into four overarching themes: , , , and .

Bakery waste supplementation to late gestating Bos indicus-influenced beef cows successfully impacted offspring postnatal performance.

This study evaluated the growth and immune function of beef calves born to cows supplemented with bakery waste containing two concentrations of crude fat. On day 0 (~90 d before calving), 108 multiparous Brangus crossbred cows were stratified by body weight (BW; 551 ± 65 kg) and body condition score (BCS, 5.5 ± 0.

Inclusion of extract into finishing diets: impacts on ruminal, physiological, and productive responses of feedlot cattle.

This experiment compared ruminal, physiological, and productive responses of feedlot cattle receiving extract to replace or fed in conjunction with monensin + tylosin. Angus-influenced steers ( = 120) were ranked by body weight (; 315 ± 3 kg) and allocated to 4 groups of 30 steers each. Groups were housed in 1 of 4 drylot pens (30 × 12 m) equipped with GrowSafe feeding systems (4 bunks/pen) during the experiment (day -14 to slaughter).

Short communication: Analysis of the nasal microbiota in newly received feedlot heifers according to subsequent incidence of bovine respiratory disease.

This study compared the relative abundance of bacteria in the nasal cavity of high-risk beef heifers at feedlot arrival according to subsequent incidence of bovine respiratory disease (BRD). Angus-influenced heifers (n = 76) were transported for 1,100 km (11 h) to the feedlot (day -1). At feedlot arrival (day 0), heifers were weighed [shrunk body weight (BW) = 234 ± 15 kg] and a nasal cavity swab collected for microbiota analysis.

Effects of supplementing narasin to heifers during late-gestation and lactation on development of the offspring.

This experiment evaluated the effects of supplementing narasin during late-gestation and lactation on productive and physiological responses of beef heifers and their offspring. Pregnant, nulliparous Nelore heifers ( = 88) that conceived under the same fixed-time artificial insemination protocol and to the same sire were used. Heifers were ranked by maternal ability genomic score, body weight () and body condition score () and allocated to 44 drylot pens (2 heifers per pen; 10 × 25 m).

Effect of Cow-Calf Supplementation on Gene Expression, Processes, and Pathways Related to Adipogenesis and Lipogenesis in Muscle of F1 Angus × Nellore Cattle at Weaning.

The aim of this study was to identify differentially expressed genes, biological processes, and metabolic pathways related to adipogenesis and lipogenesis in calves receiving different diets during the cow-calf phase. Forty-eight uncastrated F1 Angus × Nellore males were randomly assigned to two treatments from thirty days of age to weaning: no creep feeding (G1) or creep feeding (G2). The creep feed offered contained ground corn (44.

Productive and physiological responses of feedlot cattle receiving different sources of Ca salts of fatty acids in the finishing diet.

This study evaluated productive and physiological responses in feedlot cattle receiving a finishing diet that included Ca salts of palm oil (CSPALM), or a blend of Ca salts of palm, cottonseed, and soybean oils (CSMIX). Ninety yearling steers were housed in 15 pens equipped with Calan-gate feeders (6 steers/pen). Steers within each pen were stratified by shrunk body weight (BW; 410 ± 3.

Roughage level and supplemental fat for newly received finishing calves: effects on growth performance, health, and physiological responses.

This experiment evaluated the effects of roughage levels and supplemental fat on intake, growth performance, health, and physiological responses of newly received finishing cattle during 58-d receiving period. A total of 72 crossbred steers (initial body weight [BW] = 200 ± 13 kg) were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments, consisting of two roughage levels (wheat hay at 30% [R30] or 60% [R60]; dry matter [DM] basis) and two levels of supplemental fat (yellow grease at 0% [-FAT; no additional fat] or 3.5% [+FAT]; DM basis).

Effects of temperament on reproductive performance of heifers enrolled in the 7-day CO-Synch + controlled internal drug release protocol.

Cattle temperament significantly impacts production traits such as reproduction. The objective of this study was to assess the effects of temperament on pregnancy rates to fixed-timed artificial insemination (TAI) in beef heifers. A total of 297 Angus influenced heifers from 3 different locations were evaluated for temperament based on chute score and exit velocity on the first day of the estrus synchronization protocol (d-9) and classified by temperament type based on temperament score (calm ≤ 3 < excitable).