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Cowpeas [Vigna unguiculate (L) Walp] as a summer cover crop have the potential to provide N to a cool-season crop. The objectives of this study were to evaluate two cowpea cultivars grown as a cover crop to supply N for forage rye (Secale cereale L.) and to document cowpea N and C contributions to the soil. The 2-yr study was conducted at the Texas A&M AgriLife Research Center at Overton on a Darco loamy fine sand (loamy, siliceous, semiactive, thermic Grossarenic Paleudult) during 2014-2016. Treatments were arranged in a splitplot design with four replicates with cover crop as the main plot and N rate as subplot. Cover crop treatments included 'Combine' (COM) and 'Iron and Clay' (IAC) cowpeas and summer fallow. In late summer, cowpeas were incorporated as green manure, and four rates of fertilizer N were applied to rye. Total 2-yr cowpea biomass incorporated as green manure was similar at 4,596 kg ha-1 and 5,058 kg ha-1 for IAC and COM, respectively. Cowpeawas not effective as a green manure crop at providing N for rye biomass. Total soil N showed no difference (P ≥ .34) between cowpea entries or N rate within a soil depth. Each N rate increased rye biomass (P < .01) linearly (P < .001) in each year. Soil organic C from cowpeas increased about 6-8% over 2 yr. The extent of decomposition of cowpeas on the deep, sandy Darco soil limited nutrient transfer from cowpeas during this 2-yr period. [ABSTRACT FROM AUTHOR]

Sixteen forage cowpea [Vigna unguiculata (L.) Walp.] plant introduction (PI) lines were evaluated for agronomic traits and pest resistance in field and greenhouse experiments to enhance double cropping and cover crop rotation systems in northeast Texas and the southeastern United States. Cowpea cultivars 'Iron and Clay' and 'Combine', and one cowpea breeding line, TX-3, were included as controls. Cowpea lines were planted in a Darco loamy fine sand soil (a loamy, siliceous, semiactive, thermic Grossarenic Paleudult) in a randomized complete block design. Data collected in 2015 and 2016 included biomass, seed yield, and maturity stage. Plant introduction lines differed in biomass and seed production (P < .05) in both years. Biomass production ranked highest at 2,695 lb dry matter (DM) acre-1 for PI 175963 in 2015 and 2,582 lb DMacre-1 for PI 367863 in 2016. Seed yield ranked highest at 305 lb acre-1 for PI 175963 in 2015 and 2,071 lb acre-1 for PI 208845 in 2016. In a greenhouse study, 14 PI lines and two cowpea breeding lines, TX-505 and TX-3, were evaluated for susceptibility to the southern rootknot nematode (Meloidogyne incognita). Based on nematode reproduction and root galling, most of the PI lines were susceptible, while PI 367863 and TX-505 were resistant. Several PI lines were identified with improved biomass and seed production and one PI line and one breeding line with resistance to the southern root-knot nematode. These lines could be used in cowpea breeding programs to develop improved forage cowpea cultivars for double-cropping and crop-rotation systems in Texas and the southeastern United States. [ABSTRACT FROM AUTHOR]

The perennial forage model in the Decision Support System for Agrotechnology Transfer (DSSAT) suite is a newly developed model. Studies involving the use of the forage model for predicting biomass production for a perennial grass such as bermudagrass [Cynodon dactylon (L.) Pers.] are few. By conducting a series of simulation investigations, we examined the DSSAT forage model for simulating 'Coastal' bermudagrass biomass response to N as affected by soil and climate variability in the southern United States. The simulation results indicated that the DSSAT forage model predicted the biomass response to N reasonably well. However, the accuracy of simulations was linked primarily to the water holding capacity (WHC) of the soil used. A seemingly small difference in WHC, such as 0.03 mm mm-1, made a significant difference in the biomass response to N rate by a margin of about 3 Mg ha--1. These results indicated that providing more leverage to WHC than to the soil name, texture, or type being used for simulations could provide more accurate results. The simulations further indicated that bermudagrass production in the southern United States could be impacted by El Niño-Southern Oscillation (ENSO), with the La Niña and El Niño phases providing above-normal and below-normal production, respectively. The rate of increase in biomass with an increase in N rate was higher under La Niña than under El Niño. The impact of ENSO was greater on a soil with a coarser texture. [ABSTRACT FROM AUTHOR]

Winter wheat (Triticum aestivum L.) is an important component of pastures in the southern United States. This study examined winter wheat biomass responses to N application rate as influenced by soil type, planting date, drought, and El Niño-Southern Oscillation (ENSO) for the Pineywoods region of Texas using a new forage wheat model that had been incorporated into the Decision Support System for Agrotechnology Transfer suite of crop models. Biomass was simulated for various scenarios comprising two soils, three planting dates, seven N rates, and 74 yr of weather data. The biomass response to N rate was represented by a one-phase exponential association. Biomass generally peaked at 135 kg N ha-1 on the finer, more fertile Lilbert soil and at 269 kg N ha-1 on the coarser, less fertile Darco soil. Biomass decreased with a delay in planting date at N rates =135 kg N ha-1 for Lilbert and =202 kg N ha-1 for Darco. The effect of drought during September to October was greater for a higher N rate, the Darco soil, and an earlier planting date. The effect of drought during March to April was greatest at 135 kg N ha-1 and greater on Darco, with up to 45% reduction in biomass compared with 35% on Lilbert. Biomass reduction was up to 45% for the mid-October planting and 32% for the mid-September planting. Winter wheat biomass yield was not significantly affected by ENSO. These findings might assist winter wheat forage growers in this region in identifying soil type-, planting date-, and weather-specific N rates to optimize forage production. [ABSTRACT FROM AUTHOR]

Management of bermudagrass [Cynodon dactylon (L) Pers.] pastures on Coastal Plain soils in the southeastern United States incorporates multiple strategies for N fertilization, liming, and stocking rate (SR). This study documented longterm changes in soil pH and extractable NO3-N K, Ca, and Mg in Coastal and common bermudagrass pastures continuously stocked at different intensities for 37 yr (1969-2004). Soil fertility regimens were established in 1985 and consisted of (i) inorganic nitrogen fertilizer with overseeded annual ryegrass (Lolium multiflorum Lam.) (NRYG) and (ii) no nitrogen with overseeded clover (Trifolium spp.) (NoNCLV). Soil samples (0-120-cm depth) were collected in 1985, 1989, 1994, 1996, and 2004 and analyzed for pH and extractable NO3-N, K, Ca, and Mg levels. Fertility regimen showed significant effects on soil NO3-N concentration (0-15 cm) with greater values generally observed in the pastures receiving N (average NO3-N concentration of ~ 4 mg kg-1 in NoNCLV vs. 14.15 mg kg-1 in NRYG treatments). Differences in N fertilizer application levels throughout the study period also affected soil NO3-N concentration. Conversely, bermudagrass pastures receiving no inorganic N and overseeded with clover showed relatively constant soil NO3-N concentrations during the study period. Soil K levels increased (42 to 48%) over time and were generally greater in the NoNCLV pastures. It was concluded that overseeding clover without N fertilization onto bermudagrass pastures can be a viable, long-term management strategy to sustain adequate soil nutrient levels while achieving satisfactory forage and animal production. [ABSTRACT FROM AUTHOR]

Grazing systems research includes a wide array of component experimentation to assess plant-animal responses on pastures during short-term, seasonal, and long-term periods. pasture-animal experiments seek to assess forage growth responses to grazing and to quantify relationships between forage growth and nutritive value to gains per animal and per hectare. These experiments have used fixed and variable stocking rate management, continuous or rotational methods of stocking, and other stocking strategies to evaluate levels of production efficiencies. Stocking strategies require the integration of periodic and total forage mass, associated nutritive attributes, specific defoliation regimen responses, and incorporation of weather conditions to meet end-point objectives. The flexible integration processes includes forageanimal databases, availability of land resources, and intuitive experience to accommodate erratic weather conditions. Scientists have the opportunity to develop and validate stocking strategies through long-term, site-specific grazing systems research as well as collaborative, ecoregion research efforts. Documenting the influence of stocking density on nutrient cycling, stand maintenance, ecotype diversity, and watersheds will further define soil-forage-animal responses and impacts. Management prerequisites for application of stocking strategies includes foundational forage-animal interface relationships, land resource limitations, animal husbandry behavior awareness, initiation and termination of stocking sequences, projections and expectations for climatic changes, and biological and economic risk-reward expectations. Scientists involved in grazing system research are challenged to integrate soil, forage, and animal databases to discover and document production efficiencies and stocking strategies for implementation by scientists, students, and stakeholders. [ABSTRACT FROM AUTHOR]

Cancer of the eye in cattle with white faces occurs less frequently in cattle with pigmented eyelids. Corneoscleral pigmentation is related to eyelid pigmentation and occurrence of lesions that may precede cancer. Objectives of this study were to assess 1) variation in the proportion of eyelid and corneoscleral pigmentation in Hereford, Bos taurus, and Bos indicus crossbreds and 2) the occurrence of lesions with the presence of pigmentation in those areas. Hereford and Bos indicus crosses (Brahman or Nellore with Angus and Hereford and straightbred Brafords) and Bos taurus crosses (Angus-Hereford) were included in the study (n = 1,083). Eyelid pigmentation proportions were estimated by pixel quantification and were evaluated as total proportions and for upper and lower eyelids distinctly for each eye. Fixed effects included breed type, age categories, and sex of the animal. Lesion presence (1) or absence (0) was obtained by visual appraisal of image and was assumed to be binomially distributed. Eyelid pigmentation proportions (overall, upper, and lower eyelids) for Hereford ranged from 0.65 ± 0.03 to 0.68 ± 0.03 and were significantly lower than Bos indicus (range from 0.93 ± 0.02 to 0.95 ± 0.02) or Bos taurus (ranged from 0.88 ± 0.02 to 0.92 ± 0.02) crosses. Corneoscleral pigmentation in Hereford cows (0.17 ± 0.06) did not differ (P = 0.91) from Hereford calves and yearlings (0.16 ± 0.07). Bos indicus and Bos taurus crossbred cows had larger corneoscleral pigmentation (0.38 ± 0.05 and 0.48 ± 0.04 for left eyes and 0.37 ± 0.05 and 0.53 ± 0.04 for right eyes, respectively) than all calves (P < 0.001), and their corneoscleral pigmentations were greater than that of Hereford cows (P < 0.003). Bos indicus and Bos taurus cows had greater proportions of left eye corneoscleral pigmentation (0.38 ± 0.05 and 0.48 ± 0.04, respectively) than Hereford cows (0.17 ± 0.06) and all young animal breed types (P < 0.05). Right eye proportions differed for all cow groups (P < 0.05; 0.53 ± 0.04, 0.37 ± 0.05, and 0.17 ± 0.06). Among calves and yearlings, Hereford had a lower right eye corneoscleral pigmentation proportion (0.16 ± 0.07) than Bos taurus (P = 0.02). The lesion proportion for Hereford (0.08 ± 0.03) was significantly greater than that of either Bos indicus (0.01 ± 0.005) or Bos taurus (0.01 ± 0.003). Crossbreeding with Bos taurus or Bos indicus animals appears to increase eye pigmentation, which may help reduce the occurrence of cancer in eyes of cattle with white faces. [ABSTRACT FROM AUTHOR]

Pasture management affects soil properties, but information concerning the effects of long-term stocking and fertility regimens on soil P in pastures is limited. This study investigated changes in extractable soil P concentrations from Coastal and common bermudagrass [Cynodon dactylon (L) Pers.] pastures stocked for 37 yr at different intensities on an Ultisol. From 1969 through 2004, pastures were continuously stocked during February to September to achieve high, medium, and low herbage mass. Annual fall-applied P averaged 44 kg ha-1 from 1969 to1984 and 51 kg ha-1 from 1998 to 2004. Extractable soil P concentrations in the 0- to 15-cm depth increased (P ≤ 0.0001) from 5 mg kg-1 (very low) in 1975 to 43 mg kg-1 in 2004 (high), and deeper depths showed 14 to 36% increased P levels. Elimination of P fertilizer for 13 yr, 1985 to 1997, decreased (P ≤ 0.0001) extractable soil P in the 0- to 15-cm depth by 30 and 47% in common and Coastal bermudagrass pastures, respectively. An interaction between year and stocking rate was evident as extractable P levels increased after 20 yr at high stocking rates. After 37 yr, extractable P levels at the 0- to 120-cm soil depth followed the order high > medium ≥ low stocking rate. Despite the effect of stocking rate on soil P, 37 yr of continuous stocking showed no evidence of excessive P accumulation at levels that may pose an environmental threat. Phosphorus recycled through the soil-forage-animal system sustained adequate forage and animal productivity. [ABSTRACT FROM AUTHOR]

Field observations revealed greater retention of green leaf area and growth of 'Tifton 85' compared to common and 'Coastal' bermudagrass [Cynodon dactylon (L.) Pers.] underwaterstress.Ourobjective was to compare phenotypic and physiological responses to increased water stress between Tifton 85 and Coastal and between Tifton 85 and 'Tifway' bermudagrass under greenhouse conditions. Bermudagrass green leaf area, shoot and root dry weights, leaf C02 exchange rate (CER), H20 exchange rate (WER), and conductance were measured under well-watered and reduced watering in two experiments. Tifton 85 retained greater green leaf area than Tifway under water stress in Exp. 1. The CER, WER, and conductance were less for Tifton 85 than Tifway, but water stress over 8 d reduced each variable for Tifway only. In Exp. 2, soil water content and green leaf area declined more for Tifton 85 than for Coastal bermudagrass over 14 d after watering ended. Greater root dry weight below the 13-cm depth indicated Tifton 85 depleted water content of the finite pot volumes more rapidly than Coastal under reduced watering. After 14 d without watering during Exp. 2, mean CER of green leaves was less than well-watered pots for Tifton 85 but not for Coastal bermudagrass. Similar to phenotypic traits, leaf CER, WER, and conductance responses of Tifton 85 differed between experiments. These greenhouse experiments documented variation of responses to reduced soil water supply among bermudagrass and revealed the need to evaluate traits affecting water access and use for Tifton 85 and other bermudagrass under field conditions. [ABSTRACT FROM AUTHOR]

Forage-animal production agriculture is implementing infrastructure changes and management strategies to adjust to increased energy-related costs of fuel, feed grains, fertilizers, and seeds. The primary objectives of this position paper are to assess future research and extension scientific needs in forage utilization, financial support for the discipline, and changing status and number of scientists. A survey questionnaire returned from 25 land-grant universities in the eastern half of the United States rated the top 4 research needs as 1) pasture systems and efficiency of production; 2) interfacing with energy concerns; 3) forage cultivar evaluations and persistence; and 4) environment impacts. Plant-animal future research needs at 11 USDA-ARS regional locations are targeted at sustainable management and improved livestock performance, ecophysiology and ecology of grasslands, environment impacts, and improved technologies for nutritive value assessments. Extension scientists from 17 southern and northeastern states listed the top 3 needs as forage persistence, soil fertility and nutrient management, and pasture systems and efficiency of production. Grant funds currently provide more than 40% of land-grant university research and extension efforts in forage utilization, and scientists estimate that this support base will increase to 55 to 60% of the funding total by 2013. Reduced allocation of state and federal funding has contributed to a reduction in the number of full-time equivalent (FTE) scientists engaged in forage utilization research and extension activities. The current 25 state FTE conducting research number about 2.8 per state. This includes 10 states with >3, 11 states with <2, and 3 states with <1 FTE. Increased interest in cellulosic energy, climate change, and environmental impact may offer new opportunities for these FTE to participate in integrated cross-discipline research Extension programming, and technology transfer methods will change to accommodate reduced funding but with increasing numbers of novice, recreation-oriented landowners. [ABSTRACT FROM AUTHOR]

Background: High-yielding dairy cows are commonly fed high-grain rations. However, this can cause subacute ruminal acidosis (SARA), a metabolic disorder in dairy cows that is usually accompanied by dysbiosis of the rumen microbiome. Postbiotics that contain functional metabolites provide a competitive niche for influential members of the rumen microbiome, may stabilize and promote their populations, and, therefore, may attenuate the adverse effects of SARA. Methods: This study used a total of 32 rumen-cannulated lactating dairy cows, which were randomly assigned into four treatments: no SCFP (control), 14 g/d Original XPC (SCFPa), 19 g/d NutriTek (SCFPb-1X), and 38 g/d NutriTek (SCFPb-2X) (Diamond V, Cedar Rapids, IA) from 4 weeks before until 12 weeks after parturition. Grain-based SARA challenges were conducted during week 5 (SARA1) and week 8 (SARA2) after parturition by replacing 20% dry matter of the base total mixed ration (TMR) with pellets containing 50% ground barley and 50% ground wheat. The DNA of rumen solids digesta was extracted and subjected to V3-V4 16S rRNA gene sequencing. The characteristics of rumen solids microbiota were compared between non-SARA (Pre-SARA1, week 4; Post-SARA1, week 7; and Post-SARA2, weeks 10 and 12) and SARA stages (SARA1/1, SARA1/2, SARA2/1, SARA2/2), as well as among treatments. Results: Both SARA challenges reduced the richness and diversity of the microbiota and the relative abundances of the phylum Fibrobacteres. Supplementation with SCFP promoted the growth of several fibrolytic bacteria, including Lachnospiraceae UCG-009, Treponema, unclassified Lachnospiraceae, and unclassified Ruminococcaceae during the SARA challenges. These challenges also reduced the positive interactions and the numbers of hub taxa in the microbiota. The SCFPb treatment increased positive interactions among microbial members of the solids digesta and the number of hub taxa during the SARA and non-SARA stages. The SCFPb-2X treatment prevented changes in the network characteristics, including the number of components, clustering coefficient, modularity, positive edge percentage, and edge density of the microbiota during SARA challenges. These challenges reduced predicted carbohydrate and nitrogen metabolism in microbiota, whereas SCFP supplementation attenuated those reductions. Conclusions: Supplementation with SCFP, especially the SCFPb-2X attenuated the adverse effects of grain-based SARA on the diversity and predicted functionality of rumen solids microbiota. [ABSTRACT FROM AUTHOR]

Supplementation of cattle on pasture is a well-known viable strategy for increased performance per animal and per ha. Ethanol has been proclaimed as a sustainable alternative to fossil fuels, and the vast supply of dried distillers' grains with solubles (DDGS) generated from ethanol production provides opportunities for addition to feedlot rations and supplementation of grazing cattle. A large percent of the cattle in the United States are located in the Southeast, where bermudagrass is the primary introduced forage species. Since relatively few research studies have been conducted using DDGS as a supplementation on actively-growing warm-season pastures, this research represents a significant and critical knowledge database for the pasture-beef industry. The first objective of this research was to evaluate performance of stocker calves grazing 'Tifton 85' (TIF) bermudagrass with varying rates of DDGS supplementation. Steers (n = 112, 364 ± 3.5 kg BW) were stratified by BW and allocated randomly to each of 16 pastures (0.7 ± 0.01 ha) across 2 years (2014, 2015). The TIF pastures were allocated randomly to each of 4 rates of DDGS: 0, 0.25, 0.5, or 1% BW hd-1 d-1. Average daily gain was greatest (P < 0.05) from steers offered 1% BW (1.3 kg/d), and least from non-DDGS steers (0.8 kg/d), with 0.25 and 0.5% BW intermediate (1.1 and 1.2 kg/d, respectively). There were supplemental feed to additional gain ratios of 3.7, 6.0 and 9.0, respectively, for 0.25, 0.5 and 1% BW. The second objective was to evaluate performance of Bos indicus versus B. taurus stocker calves grazing 'Coastal' (COS) bermudagrass with varying rates of DDGS. Steers within a breed type (n = 117, 343 ± 4.5 kg BW) were stratified by BW and allocated randomly to each of 9 pastures (1.3 ± 0.17 ha) across 2 years (2014, 2015). Pastures were allocated randomly to each of 3 rates of DDGS: 0, 0.25, or 1% BW hd-1 d-1. Across breed types, ADG was greater (P < 0.05) from steers offered 1% BW (1.0 kg/d) than either from non-DDGS steers or 0.25% BW (0.7 kg/d each). There was no difference (P = 0.70) in ADG between breed types. The third objective of the study was to evaluate any carryover effects in long yearling stockers previously stocked on TIF or COS with varying rates of DDGS. Following the pasture x DDGS phase in the first 2 objectives, steers were shipped 693 km to a commercial feedlot for an approximate 140-d finishing phase. At finishing, animals were transported 59 km and harvested at a commercial abattoir. There was no effect (P ≥ 0.36) of DDGS for either TIF or COS during the feedlot phase. Likewise, there was no effect of DDGS on percent Low Choice for TIF (P = 0.74) or COS (P = 0.86). The fourth objective was to evaluate in vitro digestion kinetics and methane production potential of TIF or COS with varying rates of DDGS. Hand-plucked plant parts of TIF and COS were mixed independently with DDGS to represent the intake of cattle at various rates of DDGS (0, 0.25, 0.5 or 1% for TIF; 0, 0.25 or 1% for COS) in each of the first 2 objectives. Newly-generated laboratory samples were incubated in an in vitro anaerobic fermentation chamber. In vitro true degradation (IVTD) and in vitro NDF degradation (IVNDFD) were greater (P < 0.05) from TIF (69% IVTD, 57% IVNDFD) than from COS (62% IVTD, 44% IVNDFD). Treatment of DDGS did not differ (P > 0.05) within TIF for IVTD, but 1% DDGS was greater (P < 0.05) than 0%, with 0.25% DDGS intermediate to the 2 for COS. Concentration of CH4 was also greater (P < 0.05) TIF (14 mM) than COS (12 mM), and CH4:H2 ratio was less (P < 0.05) from TIF (3:1) than from COS (2:1). The fifth and final objective was to evaluate the ruminal in situ digestion kinetics of TIF as affected by forage seasonality and DDGS. Samples of TIF were harvested in June, August and October 2014. Ruminally-fistulated steers (n = 6) were stratified by BW to 3 pens, and pens were allocated randomly to 1 of 3 rates of DDGS: 0, 0.25, or 1% BW hd-1 d-1. Samples were incubated for 2, 4, 8, 12, 24, 72, and 96 h. A trend of decreasing degradation of DM, NDF, and ADF was observed with both increasing seasonality (P ≤ 0.01) and increasing DDGS (P ≤ 0.04). The undegraded fraction (UDG) of DM from TIF was least (P < 0.05) from June (19%), followed by August (34%), and greatest from October (41%). The UDG from TIF DM was not different (P = 0.47) based on DDGS, and averaged 31%. Low rates of DDGS may be feasible using TIF but not COS at our vegetational region. Rate of DDGS on pasture did not affect feedlot performance nor carcass characteristics. Increased rates of DDGS may increase forage digestibility and decrease CH4 production, but this was cultivar-dependent. Reduction of DM degradation was dependent upon seasonality more so than DDGS rate. Overall, DDGS represented a viable option for stocker production systems, and economic assessments for each specific operation-location will be required prior to implementation of a supplementation program.. [ABSTRACT FROM AUTHOR]

Supplementation of cattle on pasture is a well-known viable strategy for increased performance per animal and per ha. Ethanol has been proclaimed as a sustainable alternative to fossil fuels, and the vast supply of dried distillers' grains with solubles (DDGS) generated from ethanol production provides opportunities for addition to feedlot rations and supplementation of grazing cattle. A large percent of the cattle in the United States are located in the Southeast, where bermudagrass is the primary introduced forage species. Since relatively few research studies have been conducted using DDGS as a supplementation on actively-growing warm-season pastures, this research represents a significant and critical knowledge database for the pasture-beef industry. The first objective of this research was to evaluate performance of stocker calves grazing 'Tifton 85' (TIF) bermudagrass with varying rates of DDGS supplementation. Steers (n = 112, 364 ± 3.5 kg BW) were stratified by BW and allocated randomly to each of 16 pastures (0.7 ± 0.01 ha) across 2 years (2014, 2015). The TIF pastures were allocated randomly to each of 4 rates of DDGS: 0, 0.25, 0.5, or 1% BW hd-1 d-1. Average daily gain was greatest (P < 0.05) from steers offered 1% BW (1.3 kg/d), and least from non-DDGS steers (0.8 kg/d), with 0.25 and 0.5% BW intermediate (1.1 and 1.2 kg/d, respectively). There were supplemental feed to additional gain ratios of 3.7, 6.0 and 9.0, respectively, for 0.25, 0.5 and 1% BW. The second objective was to evaluate performance of Bos indicus versus B. taurus stocker calves grazing 'Coastal' (COS) bermudagrass with varying rates of DDGS. Steers within a breed type (n = 117, 343 ± 4.5 kg BW) were stratified by BW and allocated randomly to each of 9 pastures (1.3 ± 0.17 ha) across 2 years (2014, 2015). Pastures were allocated randomly to each of 3 rates of DDGS: 0, 0.25, or 1% BW hd-1 d-1. Across breed types, ADG was greater (P < 0.05) from steers offered 1% BW (1.0 kg/d) than either from non-DDGS steers or 0.25% BW (0.7 kg/d each). There was no difference (P = 0.70) in ADG between breed types. The third objective of the study was to evaluate any carryover effects in long yearling stockers previously stocked on TIF or COS with varying rates of DDGS. Following the pasture × DDGS phase in the first 2 objectives, steers were shipped 693 km to a commercial feedlot for an approximate 140-d finishing phase. At finishing, animals were transported 59 km and harvested at a commercial abattoir. There was no effect (P ≥ 0.36) of DDGS for either TIF or COS during the feedlot phase. Likewise, there was no effect of DDGS on percent Low Choice for TIF (P = 0.74) or COS (P = 0.86). The fourth objective was to evaluate in vitro digestion kinetics and methane production potential of TIF or COS with varying rates of DDGS. Hand-plucked plant parts of TIF and COS were mixed independently with DDGS to represent the intake of cattle at various rates of DDGS (0, 0.25, 0.5 or 1% for TIF; 0, 0.25 or 1% for COS) in each of the first 2 objectives. Newly-generated laboratory samples were incubated in an in vitro anaerobic fermentation chamber. In vitro true degradation (IVTD) and in vitro NDF degradation (IVNDFD) were greater (P < 0.05) from TIF (69% IVTD, 57% IVNDFD) than from COS (62% IVTD, 44% IVNDFD). Treatment of DDGS did not differ (P > 0.05) within TIF for IVTD, but 1% DDGS was greater (P < 0.05) than 0%, with 0.25% DDGS intermediate to the 2 for COS. Concentration of CH4 was also greater (P < 0.05) TIF (14 mM) than COS (12 mM), and CH4:H2 ratio was less (P < 0.05) from TIF (3:1) than from COS (2:1). The fifth and final objective was to evaluate the ruminal in situ digestion kinetics of TIF as affected by forage seasonality and DDGS. Samples of TIF were harvested in June, August and October 2014. Ruminally-fistulated steers (n = 6) were stratified by BW to 3 pens, and pens were allocated randomly to 1 of 3 rates of DDGS: 0, 0.25, or 1% BW hd-1 d-1. Samples were incubated for 2, 4, 8, 12, 24, 72, and 96 h. A trend of decreasing degradation of DM, NDF, and ADF was observed with both increasing seasonality (P ≤ 0.01) and increasing DDGS (P ≤ 0.04). The undegraded fraction (UDG) of DM from TIF was least (P < 0.05) from June (19%), followed by August (34%), and greatest from October (41%). The UDG from TIF DM was not different (P = 0.47) based on DDGS , and averaged 31%. Low rates of DDGS may be feasible using TIF but not COS at our vegetational region. Rate of DDGS on pasture did not affect feedlot performance nor carcass characteristics. Increased rates of DDGS may increase forage digestibility and decrease CH4 production, but this was cultivar-dependent. Reduction of DM degradation was dependent upon seasonality more so than DDGS rate. Overall, DDGS represented a viable option for stocker production systems, and economic assessments for each specific operation-location will be required prior to implementation of a supplementation program.. [ABSTRACT FROM AUTHOR]

Background: Selective grazing creates stable patches of contrasting sward height, thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon (SOC) stocks. We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass (BGB) and SOC stocks than occurs between pastures managed under different stocking intensities. Methods: A long‐term grazing experiment consisting of three stocking intensities was used for this study. We studied BGB, SOC, and soil total nitrogen (Ntot) stocks in the 0–15 cm soil depth. Shannon diversity of plant species, soil bulk density, soil phosphorus, potassium, and magnesium contents were considered. Results: There were no significant effects of patch or stocking intensity on BGB, SOC, and Ntot stocks. Short patches had a greater Shannon diversity than tall patches (p < 0.05) and plant‐available nutrients in soil correlated positively with sward height (p < 0.05). Conclusions: We conclude from the current results and previous studies that higher plant species diversity with lower soil nutrient contents in short‐patch areas and higher nutrient contents together with light competition in tall‐patch areas might balance each other out with respect to BGB and SOC stocks. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effect of calving season on the growth performance, carcass characteristics, and economic efficacy of Hanwoo (Korean native) steers. Three hundred and forty-four Hanwoo calves were employed. The calves were divided into the following two groups: spring-born calves (end of February to April; n = 167) and autumn-born calves (end of August to October; n = 177). The average daily gain (ADG) of the 3–6 months, fattening period(12-30 months of age) and experimental period (birth-30 months of age) tended to be higher for spring-born calves than for autumn-born calves(p < 0.01). The body conformation traits almost part was higher spring-born calves than autumn-born calves(p < 0.05). Spring-born calves also had higher carcass weight and back fat thickness than autumn-born calves (p < 0.05) and net income. Thus, based on birth weight, growth performance, carcass weight, and farmers' income, we recommend that calves should be produced in spring rather than autumn on seasonal breeding farms. [ABSTRACT FROM AUTHOR]

'Giant' (Reg. no. CV‐348, PI 701902) is a southern root‐knot nematode (Meloidgyne incognita race 3 and race 4)–resistant forage cowpea [Vigna unguiculata (L.) Walp.] developed by Texas A&M AgriLife Research at Overton, TX. Giant is intended for use as a warm‐season cover crop, a forage and hay crop, and supplemental browse for white‐tailed deer. Giant is an indeterminate, forage type cowpea that produces biomass from May through September in northeast Texas but also flowers 25 days earlier than 'Iron & Clay' cowpea, allowing seed production in northeast Texas before the first average frost date. Single nucleotide polymorphism analysis confirmed the variety mix Iron & Clay as the parental source population for Giant. Forage production of Giant at Overton, TX, in 2019 and 2020 was 5.3 and 6.0 Mg dry matter (DM) ha−1, respectively. Forage production of Giant in 2019 at Prairie and Starkville, MS, was 2.8 and 2.9 Mg DM ha−1, respectively. Protein content of Giant in 2019 at Prairie and Starkville was 21.1 and 21.2%, respectively. Forage production of Giant in 2019 at Chillicothe, TX and Lockett, TX, was 2.6 and 3.6 Mg DM ha−1, respectively. Top growth nitrogen (N) yield of Giant in 2019 at Chillicothe, TX, and Lockett, TX, was 67 and 65 kg N ha−1, respectively. Based on very low nematode reproduction, Giant is rated resistant and partially resistant to southern root‐knot nematode race 3 and race 4, respectively. Core Ideas: Improved cultivars of forage cowpea are needed.Giant forage cowpea produces seed earlier than Iron & Clay cowpea.Giant forage cowpea is resistant to southern root‐knot nematode. [ABSTRACT FROM AUTHOR]

We revisited terminology and assertions about grazing management in general, but more specifically the choice of the stocking method, and considered their merit in the context of evidence from the literature, including a chapter entitled Prescribed Grazing on Pasturelands from a National Resource Conservation Service (NRCS) literature synthesis published in 2012 (Nelson, 2012). We framed those assertions in the form of questions. Our objectives were to consider whether these often‐stated assertions about grazing management were supported, refuted, or simply not adequately assessed by the body of scientific evidence and to help focus future discussion about the topic. Core ideas: Choice of stocking method is only one element of grazing management.Grazing management is but one component of a grazing system, and these terms are not interchangeable.Often‐stated assertions about grazing management should be evaluated based on the body of scientific literature.What specific outcomes are improved in rotational versus continuous stocking, and to what extent?What are the mechanisms that explain those responses? [ABSTRACT FROM AUTHOR]

The incorporation of alfalfa (Medicago sativa L.) into bermudagrass [Cynodon dactylon (L.) Pers.] forage systems in the southern United States has increased. Stockpiling this mixture may extend the grazing season into the fall and winter months with high-quality forage. The objective of this 2-year study was to evaluate agronomic and structural responses of alfalfa–bermudagrass mixtures managed under five stockpiling periods (6, 8, 10, 12, or 14 weeks) in two locations (Shorter, AL, and Tifton, GA). Across locations, stockpiling mixtures for 8 weeks or longer (2400 lb DM ac−1, on average) resulted in greater (P = 0.001) herbage accumulation than 6 weeks (3185 lb DM ac−1). The alfalfa proportion was similar among stockpiling periods in Shorter but greater (P = 0.043) at 10 and 14 weeks than 6, 8, and 12 weeks in Tifton. A location × year × stockpiling interaction was observed for crude protein (CP, P < 0.001) and in vitro true dry matter digestibility over 48 h (IVTDMD48, P < 0.001). Crude protein concentrations were similar among stockpiling periods in 2020 in both locations. In 2019, however, CP concentrations reduced with increasing stockpiling period length in Shorter and were similar among treatments in Tifton, except for the lesser CP at 8 than at 10, 12, and 14, weeks. Forage IVTDMD48 concentrations declined with increasing stockpiling period length at both locations, with a more pronounced decline in Shorter in 2019. Results suggest that stockpiling alfalfa– bermudagrass mixtures for up to 8 weeks is a viable option to supply high nutritive value forage and lower lodging losses into the early winter months. [ABSTRACT FROM AUTHOR]

Accurately predicting responses to selection is a major goal in biology and important for successful crop breeding in changing environments. However, evolutionary responses to selection can be constrained by such factors as genetic and cross‐environment correlations, linkage, and pleiotropy, and our understanding of the extent and impact of such constraints is still developing. Here, we conducted a field experiment to investigate potential constraints to selection for drought resistance in rice (Oryza sativa) using phenotypic selection analysis and quantitative genetics. We found that traits related to drought response were heritable, and some were under selection, including selection for earlier flowering, which could allow drought escape. However, patterns of selection generally were not opposite under wet and dry conditions, and we did not find individual or closely linked genes that influenced multiple traits, indicating a lack of evidence that antagonistic pleiotropy, linkage, or cross‐environment correlations would constrain selection for drought resistance. In most cases, genetic correlations had little influence on responses to selection, with direct and indirect selection largely congruent. The exception to this was seed mass under drought, which was predicted to evolve in the opposite direction of direct selection due to correlations. Because of this indirect effect on selection on seed mass, selection for drought resistance was not accompanied by a decrease in seed mass, and yield increased with fecundity. Furthermore, breeding lines with high fitness and yield under drought also had high fitness and yield under wet conditions, indicating that there was no evidence for a yield penalty on drought resistance. We found multiple genes in which expression influenced both water use efficiency (WUE) and days to first flowering, supporting a genetic basis for the trade‐off between drought escape and avoidance strategies. Together, these results can provide helpful guidance for understanding and managing evolutionary constraints and breeding stress‐resistant crops. [ABSTRACT FROM AUTHOR]

The review summarizes the potential, distribution and origin of Lablab purpureus. Forage legume has potentials for the production and productivities of arable land by suppling nitrogen for the living organisms in the soil those allowed to obtain their own feed in the symbiotic relationships. Further the soil become fertile for the next cropping season even at the time of intercropping the yield would be improved than mono-cropping systems. It also supplies the protein requirement of livestock and human consumption as vegetable or as seed sources. It is summer growing annual trifoliate forage legume. The origin of lablab is considered to be in Africa because in large parts of tropical Africa wild type cultivated lablab exists. Then it is heavily distributed to the corner side of the continent and Southeast Asia for seed and vegetable production. Even though the origin and distribution of lablab initiated in the African continent the applicability and degree of uses of the species were not well recognized across countries in the continent. Therefore further conservation and evaluation of this dual purpose species give priority by governmental and non-governmental bodies. [ABSTRACT FROM AUTHOR]

Frost seeding is a low‐cost effective strategy to introduce legumes into existing perennial pastures; however, it has been deemed unreliable in the upper southeast USA. We evaluated frost seeding planting rate effects of clover (Trifolium spp.) during the year of establishment on productivity and nutritive value of clover‐tall fescue [Festuca arundinacea (Schreb.) Darbysh.] pastures. Ball (T. nigrescens Viv.), crimson (T. incarnatum L.), red (T. pratense L.), and white (T. repens L.) clover were frost seeded in the Piedmont and Coastal Plain for 3 yr (2017–2019). Planting rates were 0X, 0.5X, 1X, 1.5X, and 2X of the recommended rate (X) of 5.6, 13.5, 11.2, and 5.6 kg ha–1 for ball, crimson, red, and white clover, respectively. At Coastal Plain, clover accounted for ≤16%. At Piedmont, ball, crimson, red, and white clover accounted for up to 27, 48, 21, and 15%, respectively. Notwithstanding similar clover frequency early in the growing season at both locations, competition from tall fescue in a higher rainfall environment is attributed to the lower clover contribution at Coastal Plain. Increasing clover frost‐seeding rate resulted in greater crude protein (130–154 g kg–1) and total digestible nutrients (586–610 g kg–1) only at Piedmont. The results from this study support the practice of frost‐seeding ball, crimson, red, and white clover at planting rates of 5.6, 20.2, 11.2, and 5.6 kg ha–1, respectively, into tall fescue pastures in the Piedmont; however, minimal or no benefits of frost seeding clover were observed in the Coastal Plain. Core Ideas: Frost‐seeded clover increased diversity and nutritive value of tall fescue pastures at Piedmont.At Piedmont, ball, crimson, red, and white clover accounted for 13–48% of the forage.Minimal, or no benefits, of frost seeding clover were measured at Coastal Plain.At Coastal Plain, clover accounted for ≤16% of the total herbage harvested. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the influence of the different proportion of perennial ryegrass (Lolium perenne L.) in the meadow sward on its fodder value and daily weight gain of Highland cattle. The research was carried out on meadow sward with natural undergrowth that was cultivated by sowing perennial ryegrass. When preparing the sward for sowing, around 40% of it was damaged with a rotary tiller. The sowing rate for perennial ryegrass seeds was varied and amounted to 5, 10 and 15 kg ha−1. As a result, the following treatments of meadow sward were obtained and distinguished: semi-natural sward without sowing as the control, and three experimental treatments with approximately 18, 36 and 55% share of perennial ryegrass in the meadow sward. The animals were kept in a cowshed. In the nutritional part, the impact of feeding the obtained sward on the daily weight gain of Highland bulls and heifers was assessed. The obtained results showed higher gains in both bulls and heifers fed with sward from grasslands with a greater proportion of perennial ryegrass. The weight gain of the animals resulted from the nutrition, i.e. the quality of the feed obtained from the experimental objects. During the control fattening period, the bulls' average daily weight gain ranged from 649 g to 714 g, while for heifers 556 g to 598 g. Statistical significance (P≤0.05) in body weight gains in both bulls and heifers was shown already at 36% of perennial ryegrass in the meadow sward. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Interseeding alfalfa (Medicago sativa L.) into bermudagrass [Cynodon dactylon (L.) Pers.] can be an effective way to improve forage quality and reduce the need for additional supplementation when fed to livestock. The objective of this research was to compare the nutritive value and forage mass of bermudagrass with and without interseeded alfalfa when harvested as baleage. On 19 Feb. 2016, 0.2‐ha plots were assigned in a randomized complete block design to either 'Tifton 85' (T85) or T85 interseeded with 'Bulldog 805' alfalfa (T85+Alf) in an established field of Tifton 85 bermudagrass at the University of Georgia Tifton Campus, Tifton, GA. The T85 received 84 kg N ha−1 four times throughout the growing season. Plots were harvested at early bloom stage every 28–35 d throughout the growing season, baled at 40–60% moisture, and individually wrapped. At each harvest, plots were evaluated for botanical composition and forage mass, and bales were sampled prior to wrapping for nutritive value analysis. The T85+Alf plots produced additional harvests each season, leading to greater herbage accumulation than T85 plots (P <.01). The T85+Alf treatment had greater crude protein and total digestible nutrients than T85 in each of the 3 yr, suggesting this mixture will need no or less supplementation to meet the nutritional requirements of a lactating beef cow. Therefore, interseeding alfalfa into a bermudagrass system improves forage mass and nutritive value. [ABSTRACT FROM AUTHOR]

Stocking rate is a fundamental management factor that has major impacts on animal performance, profitability, and long-term sustainability of native range ecosystems. This research was conducted to determine the effects of stocking rate on performance and economics of growing steers grazing a mixed-grass prairie on a rolling upland red shale ecological site at the Marvin Klemme Range Research Station (35° 25′ N 99° 3′ W). The recommended sustainable stocking rate at this location is suggested to be 25 animal unit days (AUD)/ha. Steers [ n = 836, initial body weight (BW) ± SD = 216 ± 11.7 kg] grazed at seven stocking rates ranging from 4.13 ha/steer to 1.83 ha/steer over a 7-yr period, from 1990 to 1996, with year considered the random replication. During the experimental period, overall climatic conditions were favorable for forage production with average growing season precipitation of 118% of the long-term average over the 7-yr experiment, and only 1 yr (1994 with only 57% of the long-term average) with growing season precipitation substantially less than the long-term average. Over the entire summer grazing season, average daily gain (ADG) decreased linearly (P < 0.01) with increasing stocking rate, such that for each additional hectare available per steer ADG increased by 0.05 kg/d (R 2 = 0.88). Contrary to ADG, BW gain per hectare over the grazing season increased linearly (P < 0.01) with increasing stocking rate, as stocking rate increased from 4.13 ha/steer to 1.83 ha/steer BW gain per hectare doubled from 33.1 kg/ha to 66.8 kg/ha, respectively. With land costs included in the economic analysis, net return per hectare increased linearly (P < 0.01) from $13 [U.S. Dollars [USD]) at the 4.13 ha/steer to $52/ha at the 1.83 ha/steer. For each additional hectare per steer, net return was reduced by $15.80 (USD)/steer and $15.70 (USD)/ha. In favorable climatic conditions, such as during this 7-yr experiment, economically optimal stocking rates can be more than doubled compared with the stocking rate recommended by the United States Department of Agriculture (USDA) Soil Conservation Service. Increasing stocking rates decrease individual animal performance but maximize BW gain per hectare, which leads to the increasing economic returns observed. Research is needed to determine the long-term implications of these stocking rates during unfavorable growing conditions and setting stocking rates based on seasonal weather patterns and extended weather outlook predictions. [ABSTRACT FROM AUTHOR]

Abstract: This 2‐year grazing study carried out at Raymond, Mississippi, USA, evaluated animal performance and forage characteristics of a tetraploid (“Maximus”) vs a diploid cultivar (“Marshall”) of annual ryegrass at three stocking rates (SR; 3.5, 5.0 or 7.5 animals per ha). Angus cross‐bred heifers (Bos taurus; initial body weight [BW] = 240 kg) were continuously stocked on pastures at set stocking rates for the duration of the study. Stocking rates and cultivars were arranged in a 3 × 2 factorial design that was completely randomized with two replications. There was no cultivar effect (p = .449) on average annual herbage mass (HM). However, HM decreased linearly with increasing SR (p = .001) from 3.8 to 2.5 t ha−1 during Year 1 and 4.4 to 3.8 t ha−1 during Year 2 (p = .028). In Year 2, there was a difference in water‐soluble carbohydrates (WSC) between cultivars (p = .012; Marshall, 117.0 vs Maximus, 139.0 g/kg). There was no cultivar effect (p > .10) on average daily gain (ADG) in either year of the study. In both years, ADG decreased linearly with increasing SR (p = .001) from 1.22 to 0.98 kg/d during Year 1 and 1.31 to 1.08 kg/d during Year 2. Across years, gain ha−1 increased linearly (p < .001) with increasing SR. Our results showed no difference in animal performance and HM between the two cultivars. Producers’ choice of annual ryegrass cultivar should be based on seeding cost and agronomic traits that allow for better adaptation of the forage. [ABSTRACT FROM AUTHOR]

Leaf stage-dependent defoliation is linked to the plant's physiological status and may be a more suitable criterion than time-based intervals for harvesting forage grasses, but no reports of research with annual ryegrass ( Lolium multiflorum Lam. var. westerwoldicum) were found. To address this, a 2-year field study was carried out at Raymond, MS, on a Loring silt loam soil (fine-silty, mixed, thermic Typic Fragiudalfs). Forage production, morphological characteristics and nutritive value responses to defoliation based on leaf stage (2, 3 and 4 leaves per tiller) and two residual stubble heights ( RSH; 5 and 10 cm) of a tetraploid ('Maximus') vs. a diploid ('Marshall') cultivar of annual ryegrass were quantified. Forage harvested, in 2011, increased linearly as leaf stage increased from 7.3 to 8.8 Mg/ha, but during 2012 was least (7.0 Mg/ha) at 3-leaf stage and similar at the other two leaf stages (7.6 Mg/ha). Tiller density was less for Maximus (1,191 tillers/m2) than for Marshall (1,383 tillers/m2). Leaf blade proportion decreased with increasing leaf stage and was greater by 9% for Maximus than for Marshall. Generally, forage nutritive value became less desirable with increasing leaf stage. There was a dichotomy in forage harvested and nutritive value responses, but maximum forage productivity was achieved when annual ryegrass was defoliated at the 4-leaf stage interval. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Veterinary Science / Revista Brasileira de Ciência Veterinária is the property of Revista Brasileira de Ciencia Veterinaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nineteen biotypes of bermudagrass (Cynodon dactylon L. Pers.) collected in Louisiana from 17 fields planted to sugarcane and from two fields planted to other crops were compared for growth characteristics and genetic variability. In the spring of 2011, biotypes were planted in the field at the Central Research Station, Ben Hur Research Farm, Baton Rouge, LA. Biotypes A (St. Martinville), Q (Port Allen), and R (St. Gabriel) established rapidly with ground cover averaging 94% 74 days after planting (DAP) compared with 16% ground cover for biotypes J (Samuels), N (New Iberia), and T (St. Joseph). Average internode length ranged from 26 mm for biotype T to 78 mm for biotype Q and leaf width ranged from an average of 2.8 mm for biotypes G (Napoleonville), L (Plaquemine), and M (Bunkie) to 4.2 mm for biotype S (Alexandria). Average plant height ranged from 77 mm for biotype T to 325 mm for biotype Q. Bermudagrass aboveground dry weight in the establishment year for biotypes A, Q, and R averaged 1.6 to 12 times greater than for the other biotypes. In 2012, dry weight for biotypes A, B (Jeanerette), Q, and S averaged 2.4 times greater than for the lowest yielding biotype. Although some variation among biotypes in response to cold temperature was observed in December, all biotypes were aggressive in initiating regrowth in February and March. Genotyping of the bermudagrass biotypes was performed using random amplified polymorphic DNA (RAPD) analysis and biotypes were separated into three cluster groups using an unweighted pair group mean average (UPGMA) tree generated by Jaccard's similarity coefficient. Although biotypes within a cluster group were identified as genetically similar, this was not always reflected in growth characteristics. In cluster IA, a subgroup of cluster I, rate of establishment based on ground cover for biotypes J, N, and T averaged 5.3 times slower and plant height was 67% less compared with biotype Q. In sub-cluster IB, bermudagrass biomass production the first year for biotype R averaged 3.7 times more and plant height was 2.4 times greater compared with biotypes D, G, H, I, and P. Results support the variability in bermudagrass growth characteristics and aggressiveness observed in sugarcane in Louisiana and emphasize the importance of implementing effective fallow and in-crop bermudagrass control programs. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of prolonged transportation on adrenocorticotropic hormone (ACTH), cortisol, total and free triiodothyronine (T3, fT3) and thyroxine (T4, fT4) concentrations, and functional variables (heart rate (HR), respiratory rate (RR) and rectal temperature (RT)) in calm and temperamental Limousin young beef bulls. Exit velocity measurement was used to classify bulls' temperament as calm (group I: consisted of eight slowest bulls) and temperamental (group II: consisted of five fastest bulls). Calm subjects showed an increase of ACTH (P<0.05) and T4 (P<0.01) concentrations after transportation compared with before transportation values. Temperamental subjects showed higher ACTH (P<0.01) concentrations before transportation, and lower T4 (P<0.05) and fT4 (P<0.001) concentrations after transportation than calm subjects. Related to functional variables, temperamental young beef bulls showed a decrease of RT (P<0.05) after transportation compared with before values, higher RT (P<0.001) before transportation, and higher HR (P<0.001) and RR (P<0.01) after transportation than calm subjects. Data obtained suggest that longer periods of transportation could minimise the magnitude and duration of the endocrine and functional responses to stress of young beef bulls; such responses probably decrease or disappear during transport, in accordance with animal temperament. [ABSTRACT FROM AUTHOR]

We fertilized individual, pole-size ponderosa pine trees at two low-quality sites and pine saplings at a relatively high-quality site, with ammonium nitrate. Six to 12 months later, we measured total %N and 2,6-disubstituted piperidine alkaloids in the foliage. The N additions raised foliar %N above deficiency levels (i.e., from 1.0–1.1% to 1.4–1.6%) at the low-quality sites, but did not elevate foliar %N in saplings at the higher quality site, where it was already (1.9%) well above critical levels. In control trees with foliar N below a threshold of 1.1%, we detected no more than trace levels of alkaloids, indicating that alkaloid production is highly constrained by N deficiency. The N additions increased mean concentrations of the predominant alkaloid, pinidine, at all three sites. Mean total alkaloid concentrations for fertilized trees at the two low-quality sites were 12 and 155 μg/g dry wt higher than controls (relative increases of 12× and 4.5×, respectively). For saplings at the high-quality site, the mean total increased by 584 μg/g dry wt (1.6×) with the N additions. Allocation of foliar N to alkaloids was highest in fertilized saplings (0.81%) compared to control saplings (0.53%). These findings demonstrate that foliar alkaloid concentrations can be increased by nitrogen fertilization of forest trees growing on both low- and high-quality sites. Fertilizing for the purpose of inhibiting potential herbivores may be more successful at higher quality sites where alkaloid levels are enhanced relative to food quality (foliar %N). [ABSTRACT FROM AUTHOR]

Information about the annual meeting of the Forage and Grazinglands Division of the crop organization the Crop Science Society of America held in Long Beach, California in November 2014 is presented. The event was organized to furnish attendees with solutions to the challenges they experienced in grazing research, the importance of the said study, and the applications of the grazing study.