@article{coffey_coblentz_hellwig_popp_smith_hubbell_scarbrough_humphry_turner_johnson_et al._2008, title={Weaning and post-weaning performance by fall-born calves weaned on different dates from endophyte-infected tall fescue pastures managed with two different rotation frequencies}, volume={118}, ISSN={["1878-0490"]}, DOI={10.1016/j.livsci.2008.01.019}, abstractNote={A number of studies have reported performance by spring-calving cows grazing Neotyphodium-infected fescue [E+, Lolium arundinaceum (Schreb.) Darbysh.], but post-weaning calf performance from the majority of those studies is limited. Furthermore, both pre- and post-weaning information pertaining to fall-calving cows and their calves grazing E+ is particularly limited. A 3-year study was initiated in April 2000 near Batesville, AR (USA) to investigate the impact of rotational management (twice monthly vs. twice weekly) program and weaning date [mid-April (EARLY) vs. early June (LATE)] on production of fall-calving cow-calf pairs grazing E+ overseeded with ladino (Trifolium repens L.), and red clover (Trifolium pretense L), lespedeza (Lespedeza stipulacea Maxim.), and crabgrass (Digitaria sanguinalis (L.) Scop.). A secondary objective of the study was to evaluate calf performance both at weaning and after weaning until either breeding of the heifers or slaughter of the steers. Calves weaned later had greater (P < 0.05) actual weaning weights, but weaning date × year interactions were detected (P < 0.05) for most measurements at weaning. Weight loss during a simulated transport and sale, as well as the days required to regain the lost weight were lower (P < 0.05) by EARLY than by LATE in 2 of 3 years, and intake (kg DM/100 kg BW) was higher by EARLY than by LATE in 2 of 3 years. Antibody titers to infectious bovine rhinotracheitis and bovine virus diarrhea measured prior to vaccination and at weaning were greater (P < 0.05) from EARLY than from LATE. Heifer weight at breeding was greater (P < 0.05) from LATE than from EARLY in 1 year and numerically greater (P ≥ 0.11) from LATE in the other 2 years. Initial and final feedlot BW and gain did not differ (P ≥ 0.16) among previous treatments in 2 of 3 years. Therefore, carryover effects of weaning date or rotational grazing on calves previously grazing E+ tall fescue may be mitigated during a subsequent backgrounding period such that impacts on subsequent breeding or feedlot performance is minimized.}, number={3}, journal={LIVESTOCK SCIENCE}, author={Coffey, K. P. and Coblentz, W. K. and Hellwig, D. H. and Popp, M. P. and Smith, T. F. and Hubbell, D. S., III and Scarbrough, D. A. and Humphry, J. B. and Turner, J. E. and Johnson, Z. B. and et al.}, year={2008}, month={Nov}, pages={183–194} }
 @article{scarbrough_coblentz_coffey_hubbell_smith_humphry_jennings_ogden_turner_2006, title={Effects of forage management on the nutritive value of stockpiled bermudagrass}, volume={98}, ISSN={["0002-1962"]}, DOI={10.2134/agronj2006.0012}, abstractNote={‘Common’ and ‘Tifton 44’ bermudagrass [Cynodon dactylon (L.) Pers.] located near Fayetteville and Batesville, AR, respectively, were chosen to evaluate the effects of stockpiling initiation date (August or September), and N fertilization rate (0, 37, 74, or 111 kg N ha−1) on the nutritive value of fall‐stockpiled bermudagrass. At the Fayetteville location, there were initiation × harvest date interactions for acid detergent fiber (ADF, P = 0.003), hemicellulose (P = 0.003), cellulose (P = 0.0003), lignin (P = 0.007), and crude protein (CP, P = 0.008) in 2000, and strong interactions (P ≤ 0.001) for all response variables in 2001. Generally, neutral detergent fiber (NDF), ADF, cellulose, and lignin increased over harvest dates for both initiation dates in 2000, although increases for lignin were only numerical (P > 0.05) for the September initiation date. Similar responses were observed for the August initiation date in 2001, but fiber components for the September 2001 initiation date declined over time because of contamination by other winter‐annual species. For August initiation dates in 2000 and 2001, in vitro organic matter disappearance (IVOMD) declined linearly (P ≤ 0.002) over harvest dates, reaching respective minima of 330 and 361 g kg−1. At the Batesville site, an N fertilization effect (P ≤ 0.017) was observed for NDF, ADF, and CP in both 2000 and 2001. A similar effect was observed for lignin (P = 0.001) and IVOMD (P < 0.0001) in 2000, and for cellulose (P = 0.0004) during 2001. Fertilization with N at the initiation of stockpiling generally reduced fiber components, and increased CP; however, IVOMD was increased for 2000 only. As observed for the Fayetteville site, most fiber components increased over harvest dates, while IVOMD declined concomitantly. Generally, the nutritive value of stockpiled bermudagrass declines between mid‐October and mid‐December, and spring‐calving beef cows in the Upper South may need to be supplemented with energy to maintain body condition in the late fall or early winter.}, number={5}, journal={AGRONOMY JOURNAL}, author={Scarbrough, D. A. and Coblentz, W. K. and Coffey, K. R. and Hubbell, D. S., III and Smith, I. E. and Humphry, J. B. and Jennings, J. A. and Ogden, R. K. and Turner, J. E.}, year={2006}, pages={1280–1289} }
 @article{scarbrough_coblentz_ogden_turner_humphry_coffey_daniel_sauer_jennings_kellogg_2006, title={Nitrogen partitioning and estimates of degradable intake protein in wilting orchardgrass and bermudagrass hays damaged by simulated rainfall}, volume={98}, ISSN={["1435-0645"]}, DOI={10.2134/agronj2005.0091}, abstractNote={This study investigated the effects of simulated rainfall on N partitioning and concentrations of degradable (DIP) or undegradable (UIP) intake protein for wilting orchardgrass (Dactylis glomerata L.) and bermudagrass [Cynodon dactylon (L.) Pers.] hays. Orchardgrass forage was wilted to 674, 153, or 41 g kg−1 of moisture (WET‐O, IDEAL‐O, and DRY‐O, respectively) in the field before applying the simulated rainfall (0, 13, 25, 38, 51, 64, or 76 mm). For WET‐O, DIP (g kg−1 crude protein [CP]) increased cubically (P = 0.020) with simulated rainfall, but the overall range of response was small (653–673 g kg−1 CP). Estimates of DIP (g kg−1 CP) for IDEAL‐O and DRY‐O decreased by 46 and 25 g kg−1 CP, respectively, between the 0‐ and 76‐mm rainfall increments; for IDEAL‐O, these decreases occurred in a linear (P < 0.0001) pattern, whereas quadratic (P = 0.009) and linear (P = 0.029) effects were observed for DRY‐O. Bermudagrass forage was field wilted to 761, 400, or 130 g kg−1 of moisture (WET‐B, MID‐B, and IDEAL‐B, respectively) and evaluated similarly. For WET‐B and MID‐B, DIP (g kg−1 CP) was not affected (P > 0.05) by simulated rainfall. In contrast, quartic (P = 0.019) and linear (P = 0.002) effects were observed for IDEAL‐B, but these responses were confined primarily to changes between the undamaged (0‐mm) control and the initial 13‐mm rainfall increment. On a practical basis, concentrations of DIP were, at most, altered only moderately in response to simulated rainfall and relatively little when forages were still too wet to bale.}, number={1}, journal={AGRONOMY JOURNAL}, author={Scarbrough, DA and Coblentz, WK and Ogden, RK and Turner, JE and Humphry, JB and Coffey, KP and Daniel, TC and Sauer, TJ and Jennings, JA and Kellogg, DW}, year={2006}, pages={85–93} }
 @article{coblentz_coffey_smith_hubbell_scarbrough_humphry_mcginley_turner_jennings_west_et al._2006, title={Using orchardgrass and endophyte-free fescue versus endophyte-infected fescue overseeded on bermudagrass for cow herds: I. Four-year summary of forage characteristics}, volume={46}, ISSN={["0011-183X"]}, DOI={10.2135/cropsci2005.11-0442}, abstractNote={A systems trial was designed to evaluate forage characteristics within mixed‐species pastures consisting of (i) endophyte‐infected tall fescue (Festuca arundinacea Schreb.; E+) mixed with common bermudagrass [Cynodon dactylon (L.) Pers.] and other forages; (ii) endophyte‐free tall fescue (E−) overseeded into dormant common bermudagrass; and (iii) orchardgrass (OG; Dactylis glomerata L.) established under the same conditions as E−. The E− and OG pastures were grazed with either twice weekly (2W) or twice monthly (2M) rotation schedules, but E+ was grazed only as 2M. Across 41 sampling dates (2000 through 2003) the mean forage mass across all forage systems was 3809 kg ha−1, and there was an interaction of forage system and sampling date (P = 0.001). In vitro dry matter disappearance (IVDMD) and crude protein (CP) varied (P < 0.0001) with sampling date in seasonal patterns that were generally predictable. Frequencies of tall fescue in E− and E+ pastures increased (P < 0.10) over years, reaching numerical maxima (61 to 72%) at the end of the trial. For OG, frequencies reached numerical maxima of 52 and 42% in 2W and 2M pastures, respectively, but then declined (P < 0.10) over time, ending at 39 and 24%, respectively. At the end of the trial, reinfection of OG pastures by rogue E+ plants reached a numerical maximum frequency of only 10%, and concentrations of total ergot alkaloids in tall fescue plants from E− pastures were only about 25% of those for E+ pastures, thereby suggesting that pasture toxicity can be reduced substantially for at least 5 yr using these alternative forage systems.}, number={5}, journal={CROP SCIENCE}, author={Coblentz, W. K. and Coffey, K. P. and Smith, T. F. and Hubbell, D. S., III and Scarbrough, D. A. and Humphry, J. B. and McGinley, B. C. and Turner, J. E. and Jennings, J. A. and West, C. P. and et al.}, year={2006}, pages={1919–1928} }
 @article{coblentz_coffey_smith_hubbell_scarbrough_humphry_mcginley_turner_jennings_west_et al._2006, title={Using orchardgrass and endophyte-free fescue versus endophyte-infected fescue overseeded on bermudagrass for cow herds: II. Four-year summary of cow-calf performance}, volume={46}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2005.11-0443}, abstractNote={A 4‐yr trial was initiated in January 2000 to evaluate cow‐calf performance on mixed‐species pasture systems consisting of (i) endophyte‐infected tall fescue (E+; Festuca arundinacea Schreb.) diluted by approximately 50% with common bermudagrass [Cynodon dactylon (L.) Pers.] and other forages; (ii) endophyte‐free tall fescue (E−) overseeded into dormant common bermudagrass; and (iii) orchardgrass (OG; Dactylis glomerata L.) established under the same conditions as E−. The E− and OG pastures were grazed with either twice weekly (2W) or twice monthly (2M) rotation schedules, while pastures with E+ were grazed with 2M only. Actual weaning weights tended to be greater (P = 0.096), and age‐adjusted 205‐d weaning weights and average daily gain from birth to weaning were greater (P ≤ 0.035) for calves raised on low‐toxicity (E− or OG) pastures compared to those raised on E+. Over 4 yr, calves raised on low‐toxicity pastures exhibited 22‐ and 24‐kg advantages in actual and 205‐d adjusted weaning weights, respectively, compared to those raised on E+. Cows grazing OG and E− pastures exhibited greater (P ≤ 0.021) body weights and body condition scores (BCS) at calving than cows grazing E+ pastures. Furthermore, reductions in body weight and BCS between calving and weaning tended to be greater (P ≤ 0.088) for cows grazing E+ pastures. Calf performance was improved consistently by these low‐toxicity pasture systems, but management requirements may limit adaptation by producers.}, number={5}, journal={CROP SCIENCE}, author={Coblentz, W. K. and Coffey, K. P. and Smith, T. F. and Hubbell, D. S., III and Scarbrough, D. A. and Humphry, J. B. and McGinley, B. C. and Turner, J. E. and Jennings, J. A. and West, C. P. and et al.}, year={2006}, pages={1929–1938} }
 @article{scarbrough_coblentz_humphry_coffey_daniel_sauer_jennings_turner_kellogg_2005, title={Evaluation of dry matter loss, nutritive value, and in situ dry matter disappearance for wilting orchardgrass and bermudagrass forages damaged by simulated rainfall}, volume={97}, ISSN={["1435-0645"]}, DOI={10.2134/agronj2005.0604}, abstractNote={Throughout much of the southeastern USA, hay harvest can be complicated by a high probability of rainfall events that may cause damage to the resultant hay crop. The objectives of this study were to investigate the effects of simulated rainfall and two postrainfall drying methods on losses of dry matter (DM) and changes in nutritive value for wilting orchardgrass (Dactylis glomerata L.) and bermudagrass [Cynodon dactylon (L.) Pers.] forages. Orchardgrass was wilted to moisture concentrations of 674 (WET), 153 (IDEAL), and 41 (DRY) g kg−1 and subjected to 0, 12, 25, 38, 51, 64, or 76 mm of simulated rainfall from a custom‐built rainfall simulator. For IDEAL orchardgrass, DM loss reached a maximum of 88 g kg−1 when 76 mm of simulated rainfall was applied. Dry matter loss, total N, and all fiber components except hemicellulose increased with rainfall amount, exhibiting single or multiple polynomial effects (P ≤ 0.048) in each case; however, responses were not consistent across these response variables. A second study was conducted with bermudagrass using similar techniques, except that the forage contained 761 (WET), 400 (MID), and 130 (IDEAL) g kg−1 of moisture when simulated rainfall was applied. For IDEAL bermudagrass forage, DM losses increased in linear (P = 0.001) and quadratic (P = 0.003) relationships with simulated rainfall, but the maximum DM loss was only 21 g kg−1. For both forages, DM loss and deleterious changes in nutritive value generally increased with rainfall amount, but these responses appeared to be much greater for orchardgrass.}, number={2}, journal={AGRONOMY JOURNAL}, author={Scarbrough, DA and Coblentz, WK and Humphry, JB and Coffey, KP and Daniel, TC and Sauer, TJ and Jennings, JA and Turner, JE and Kellogg, DW}, year={2005}, pages={604–614} }
 @article{turner_coblentz_coffey_rhein_mcginley_galdamez-cabrera_rosenkrans_johnson_kellogg_skinner_2004, title={Effects of natural rainfall and spontaneous heating on voluntary intake, digestibility, in situ disappearance kinetics, passage kinetics, and ruminal fermentation characteristics of tall fescue hay fed to growing steers}, volume={116}, ISSN={["1873-2216"]}, DOI={10.1016/j.anifeedsci.2004.05.004}, abstractNote={Relatively little is known about the combined effects of spontaneous heating and natural rainfall on the feeding value of ‘Kentucky 31’ tall fescue (Festuca arundinacea Schrieb.) hay infested with the fungal endophyte Neotyphodium coenophialum (Morgan-Jones & Glenn, Bacon, and Hamlin comb. nov.). A digestion trial utilizing a 4 × 4 Latin square design was initiated to determine the effects of both natural rainfall before baling and spontaneous heating during storage on the voluntary intake, digestibility, in situ disappearance kinetics, and ruminal fermentation characteristics of tall fescue hay consumed by four 227 ± 20.5 kg steers. The four tall fescue hays utilized in this experiment were baled at 99 (low, L), and 225 g/kg (high, H) moisture prior to rainfall, and at 246 g/kg moisture after a 23 mm rainfall event (H–R) and at 93 g/kg moisture after a total accumulation of 72 mm of rain (L–R). Daily voluntary intake of the total diet, and dry matter (DM) and organic matter (OM) intakes of hay (g/kg body weight) were greater (P ≤ 0.032) for steers consuming hays baled without rainfall prior to baling than for those receiving rainfall during the wilting period. However, hays altered by rain had greater (P ≤ 0.033) apparent digestibilities of DM, OM, NDF, and ADF than did hays baled without rainfall. Effective in situ disappearance of DM and N was poorer (P ≤ 0.033) for hays altered by rainfall, spontaneous heating, or both (H, H–R, and L–R) than for L hay, but effective NDF disappearance was not affected by treatment (P ≥ 0.361). Ruminal fermentation characteristics and passage kinetics varied little between the four diets. Although hay receiving no rainfall had slightly better characteristics of nutritive value and in situ degradation than hays altered by rainfall, apparent total tract digestibilities were higher for hays altered by rainfall. While depressed total tract digestibilities in hay baled without rainfall were clearly associated with higher voluntary intakes, statistically significant decreases in ruminal or total tract retention times could not be established clearly.}, number={1-2}, journal={ANIMAL FEED SCIENCE AND TECHNOLOGY}, author={Turner, JE and Coblentz, WK and Coffey, KP and Rhein, RT and McGinley, BC and Galdamez-Cabrera, NW and Rosenkrans, CF and Johnson, ZB and Kellogg, DW and Skinner, JV}, year={2004}, month={Sep}, pages={15–33} }