On public lands grazing allotments in the western US sagebrush steppe, cattle are generally excluded from burned pastures for 2 yr post fire. If only a portion of pasture burns, area may be fenced, allowing to resume unburned portion. However, traditional wire-based fencing is often not an option due expense, conflicts with wildlife management objectives, and extensive procedural logistics. We evaluated use "virtual fence" (VF) excluding areas within small steppe southeast Oregon. VF...

Two studies were conducted to determine the influence of CP degradability and supplementation frequency (SF) on ruminant performance N efficiency. Treatments included an unsupplemented control (CON) degradable intake protein (DIP; 82% CP) or undegradable (UIP; 60% provided daily, every 3 d, 6 d. Seven wethers (36+/-1 kg BW) used in digestibility study with DIP UIP treatments formulated meet requirements. Eighty-four Angus x Hereford cows (512+/-42 last third gestation for study. The...

The objective of this study was to compare the effects 24-h road transport or feed and water deprivation on acute-phase performance responses feeder cattle. Angus × Hereford steers (n = 30) heifers 15) were ranked by gender BW (217 ± 3 kg initial BW; 185 2 d age) randomly assigned 15 pens -12 experiment (3 animals/pen; 1 heifer). Cattle fed alfalfa-grass hay ad libitum 2.3 kg/animal daily (DM basis) a corn-based concentrate throughout (d 28). On 0, treatments: 1) for 24 h in livestock...

Two experiments evaluated the effects of temperament and acclimation to handling on reproductive performance Bos taurus beef females. In Exp. 1, 433 multiparous, lactating Angus × Hereford cows were sampled for blood before breeding season. Cow was assessed by chute score exit velocity. Chute a 5-point scale according behavioral responses during restraining. Exit calculated dividing velocity into quintiles assigning with from 1 5 (1 = slowest, fastest cows). Temperament averaging scores....

A 2-yr study utilizing 120 mature, crossbred (Angus × Herford) cows/year, evaluated the influence of cow BCS and dried distillers grains with solubles (DDGS) supplementation during late gestation on performance productivity subsequent offspring. Treatments were arranged as a 2×2 factorial in randomized complete block design 2 or without DDGS supplementation. Cows nutritionally managed to enter last trimester approximately 4 (LBCS) 6 (HBCS) thereafter single herd (initial 4.4 5.7 for LBCS...

Eighty-four multiparous, nonlactating, pregnant Angus × Hereford cows were ranked by pregnancy type (56 AI and 28 natural service), BW, BCS allocated to 21 drylot pens at the end of their second trimester gestation (d 0). Pens assigned receive forage-based diets containing 1) sulfate sources Cu, Co, Mn, Zn (INR); 2) an organic complexed source (AAC; Availa 4; Zinpro Corporation, Eden Prairie, MN); or 3) no supplemental (CON). Diets offered from d 0 until calving formulated meet requirements...

The objective of this study was to compare performance, physiological, and reproductive responses beef heifers consuming forages differing in nutritional quality offered a low-starch energy supplement at 2 different frequencies. Forty-eight Brahman × British (initial age = 294 ± 3 d) were allocated into 1 16 drylot pens (3 heifers/pen) which randomly assigned receive, factorial arrangement treatments: 1) low-quality hay [LQ; stargrass (Cynodon nlemfuensis) with 8% CP 81% NDF, DM basis] daily...

The objective of this study was to evaluate plasma concentrations cortisol, acute-phase proteins, and proinflammatory cytokines in beef steers after an intravenous corticotrophin-release hormone (CRH) infusion. Six weaned, halter-trained Angus (BW = 163 ± 7.0 kg; age 203 5.8 d) were fitted with indwelling jugular catheters on d -1 the assigned receive intravenously 0.1 μg bovine CRH/kg BW 0 study. Blood samples collected every hour via from 8 h, 6 h venipuncture 12 72 relative CRH infusion...

Angus×Hereford steers (n = 42) and heifers 21) were ranked by gender BW on d 0 of the experiment randomly assigned to 1 3 treatments: 1) no transport full access feed water (CON); 2) continuous road for 1,290 km (TRANS), or 3) km, with rest stops every 430 (STOP; total 2 stops). Treatments applied from experiment. Cattle TRANS STOP treatments transported in separate commercial livestock trailers, within a single 2.1×7.2 m compartment, but through exact same route. During each stop, cattle...

An in situ study (Exp. 1) using 4 ruminally cannulated steers (343 ± 11 kg of BW) a completely randomized design was used to compare ruminal degradation characteristics low-quality cool-season (C3; Kentucky bluegrass straw; Poa pratensis; 6.3% CP; DM basis) and warm-season (C4; tallgrass prairie; 5.7% forage. Four (252 8 BW; Exp. 2) wethers (38 1 3) were two 2 × factorial arrangements treatments determine the influence supplemental CP (CPSupp; soybean meal; 0.09 0.19% BW, basis, for lambs,...

Two experiments were conducted to compare ruminal, physiological, and performance responses of forage-fed cattle consuming grain-based supplements without (NF) or with the inclusion (10%; DM basis) a rumen-protected PUFA (PF) SFA source (SF). Supplements offered consumed at 0.6% BW/animal daily (DM basis). In Exp. 1, DMI ruminal in situ forage degradability evaluated 3 Angus × Hereford cows fitted cannulas allocated Latin square design. Within each experimental period, hay was amounts ensure...

Two experiments evaluated the effects of temperament and acclimation to handling on performance Angus × Hereford feeder cattle reared in extensive rangeland systems until weaning. In Exp. 1, 200 calves (n = 97 for yr 1; n 103 2) were at weaning (average age ± SE 152 1 d) by chute score exit velocity. Chute was assessed a 5-point scale according behavior during restraining. Exit calculated dividing velocity into quintiles assigning from (slowest) 5 (fastest). A each calf averaging scores....

This experiment evaluated the effects of temperament on physiological, productive, and reproductive responses in Bos indicus beef cows. A total 953 lactating, multiparous, non-pregnant Nelore cows (age = 99 ± 2 mo; days post-partum 51.4 0.3 d; BCS 5.34 0.04; BW 430 kg) were allocated into 8 groups approximately 120 each. Groups assigned to an estrus synchronization + timed-AI protocol at beginning breeding season. Concurrently with AI, blood samples collected, hair clipped from tail switch,...

This experiment evaluated the influence of supplement composition on performance, reproductive, and metabolic responses Angus × Hereford heifers consuming a low-quality cool-season forage (8.7% CP 57% TDN). Sixty (initial age = 226 ± 3 d) were allocated into 15 drylot pens (4 heifers/pen 5 pens/treatment) assigned to 1) supplementation with soybean meal (PROT), 2) mixture cracked corn, meal, urea (68:22:10 ratio, DM basis; ENER), or 3) no (CON). Heifers offered meadow foxtail (Alopecurus...

Seven cannulated (rumen and duodenal) Angus × Hereford steers (264 ± 8 kg BW) consuming low-quality forage (5% CP; 61% NDF; 31% ADF) were used to determine the influence of CP degradability supplementation frequency (SF) on DMI nutrient digestion. Treatments included an unsupplemented control degradable intake protein (DIP) or undegradable (UIP) provided daily, every 3 d, 6 d. The DIP treatments (18% UIP) calculated provide 100% requirement, while UIP (60% isonitrogenous basis compared with...

The objectives of this research were to determine the influence protein supplementation frequency on cow performance, grazing time, distance traveled, maximum from water, distribution, DMI, DM digestibility, harvest efficiency, percentage events frequented, and CV for supplement intake cows low-quality forage. One hundred twenty pregnant (60 ± 45 d) Angus × Hereford (467 4 kg BW) used in a 3 Latin square design one 84-d period each three consecutive years. Cows stratified by age, BCS, BW...

The objective was to compare the acute-phase response of steers receiving different doses bovine corticotropin-releasing hormone (CRH). Fourteen weaned Angus (BW = 191 ± 2.1 kg, age 167 4.7 d) fitted with an indwelling jugular catheter and a rectal temperature (RT) monitoring device were assigned receive 1 3 treatments (intravenous infusion): 1) 0.1 μg CRH/kg BW (CRH1; n 5), 2) 0.5 (CRH5; 3) 10 mL saline (0.9%; 4). Blood samples collected via catheters, relative treatment infusion (0 h),...

The objective of this study was to evaluate intake, metabolic, inflammatory, and acute-phase responses in beef heifers vaccinated against pathogens that cause bovine respiratory disease (BRD). Eighteen weaned Angus (initial BW 257 ± 3 kg; initial age 245 2 d) were ranked by allocated groups, which assigned experiments 7 d the following treatments on 1 each experiment: 1) revaccinated infectious rhinotracheitis virus, parainfluenza-3 syncytial viral diarrhea Types viruses, (VAC; mL [s.c.]) 2)...

In all, 60 Angus×Hereford heifers were ranked by age and BW (210±2 days 220±2 kg) on day 0, assigned to: (a) one of three drylot pens (10×14 m pens; 10 heifers/pen) resulting in a stocking density 14 m2/heifer (HIDENS; n=3), or (b) pastures (25 ha pastures; heifers/pasture), 25 000 (LOWDENS; n=3). Pastures harvested for hay before the beginning this experiment, negligible forage was available grazing to LOWDENS during experiment (days 0 182). All received same limited-fed diet, which...