Influence of Hempseed Meal on Fresh Goat Meat Characteristics Stored in Vacuum Packaging

The objective of this study was to determine the influence of hempseed meal (HSM) on goat meat characteristics. Goats (N = 10/treatment) were allocated to a diet concentration (0, 10, 20, or 30%) of HSM, fed for 60 days, and harvested. Carcass measurements were collected after chilling, and subsequently fabricated into wholesale subprimals. From the subprimals of the shoulder and leg, steaks were cut 2.54 cm thick, vacuum packaged, and assigned to laboratory methods: cook yield, instrumental color, lipid oxidation, microbial spoilage, and instrumental tenderness. HSM did not alter (p > 0.05) carcass characteristics, microbial spoilage, cook loss, or the thiobarbituric acid reactive substance (TBARS). However, a decrease in objective tenderness measurements (p < 0.05) was observed with greater concentrations of HSM supplementation in the diet. Instrumental surface color values for lightness (L*) indicated that steaks became lighter and less red (a*) as storage time increased (p < 0.05). Results suggest that HSM and storage time do not alter some goat meat traits, but HSM or storage time separately may influence goat meat quality. HSM may be an effective feed ingredient that does not alter carcass quality or meat yield.

174 Forage Production and Nutritive Value of Alfalfa-bermudagrass Mixtures Managed Under Contrasting Defoliation Strategies in the Southeast US

Incorporation of alfalfa (Medicago sativa) into bermudagrass pastures improves forage quality and decreases the reliance on synthetic nitrogen fertilizer. The objective of this study was to determine forage mass (FM), nutritive value (NV), and botanical composition of ‘Bulldog 805’ alfalfa and ‘Tifton 85’ bermudagrass (T85; Cynodon dactylon) mixtures managed under three defoliation strategies: 1) hay production (H), 2) grazing (G) or 3) dual-purpose (DP) use. The study was conducted in two locations (Headland, AL and Tifton, GA) using a randomized complete block design with two replicates. In spring 2020, grazed plots were divided in four strips and every 7-d, animals were rotated to a new strip and stocking rate was adjusted. Under DP, plots were grazed until mid-July, then forage was harvested in late August. For H plots, forage was harvested every 28 to 35-d. Forage samples were collected prior defoliation to determine FM and on grazed periods, pre- and post-grazing samples and disk meter measurements were collected. Nutritive value responses were determined using near-infrared spectroscopy. There was no effect of defoliation strategy on FM (P = 0.604; mean 3471 kg DM/ha). Greater FM (P = 0.002) was observed in July and August than June (3531 and 3976 vs 2905 kg DM ha-1, SE= 263). This response was associated with an up to 40% increase of T85 proportion in the mixture (P = 0.001). Alfalfa percentage was 78% greater for DP than G (P = 0.029). There were no differences among treatments for NV responses (P &gt; 0.05). Among defoliation periods, crude protein, neutral detergent fiber and acid detergent fiber concentrations ranged from 14 to 22%, 45 to 58% and 28 to 35%, respectively. These preliminary results demonstrate multi-use options for this mixture in the region while aiming for increased forage nutritive value, and extended growing season, and sustainability of forage-livestock systems.

173 Grazing Cover Crops: Effects of Cattle Removal Date on Forage Production and Cattle Performance

Use of cool-season annual cover crops through grazing has been shown to be a potential tool in extending the grazing season, while still mitigating environmental risks associated with warm-season row crop production. Although data describing the effects of grazing on soil health are not novel, effects of grazing length on animal performance and cover crop production are limited. The objective was to determine cattle performance and forage production when grazing a cool-season annual cover-crop. Twelve, 1.2-ha pastures were established in a four species forage mix and randomly allocated to be grazed through either mid-February (FEB), mid-March (MAR), or mid-April (APR) with a non-grazed control (CON). Three tester steers were randomly placed in each paddock and a 1:1 forage allowance was maintained in each paddock using put-and-take steers. Animals were weighed every 30 d for determination of average daily gain (ADG). Forage was harvested bi-weekly and analyzed for forage production, neutral detergent fiber (NDF), and acid detergent fiber (ADF). Fiber fractions were measured using an ANKOM fiber analyzer (ANKOM Tech, Macedon, NY). All data were analyzed using MIXED procedure of SAS version 9.4 (SAS Inst., Cary, NC). Differences in forage mass were detected between CON and FEB (3,694.75 vs. 2,539.68 kg/ha; P &lt; 0.003), CON and MAR (3,694.75 vs. 1,823.45 kg/ha; P &lt; 0.001), and CON and APR (3,694.75 vs. 1,976.23 kg/ha; P &lt; 0.001). Differences in total gain/acre were detected between APR and MAR (212.24 vs. 101.74 kg/ha; P &lt; 0.0001), APR and FEB (212.24 vs 52.65 kg/ha; P &lt; 0.0001), and FEB and MAR (101.74 vs. 52.65 kg/ha; P &lt; 0.003). No differences were detected for tester ADG (1.23 kg/day, P = 0.56), NDF (44.9%, P = 0.99), or ADF (27.2%, P = 0.92) among treatments. These results indicate that cattle removal date effected forage yield and total gain/hectare.

Evaluation of nitrogen-delivery methods for stocker cattle grazing annual ryegrass

A 2-yr grazing experiment was conducted to evaluate efficacy of nitrogen (N) fertilization, interseeded legumes, and protein supplementation for N delivery to stocker cattle grazing annual ryegrass (Lolium multiflorum). Each year, 90 steers (initial BW, 241 ± 13 kg) were assigned to the following N-delivery methods, with or without monensin fed in a free-choice mineral supplement as a 5 × 2 factorial arrangement of treatments: ryegrass fertilized with 112 kg N/ha (NFERT); ryegrass interseeded with crimson clover (CC, Trifolium incarnatum); ryegrass interseeded with arrowleaf clover (AC, Trifolium vesiculosum); ryegrass plus distillers dried grains with solubles (DDGS) supplemented at 0.65% BW daily; and ryegrass plus whole cottonseed (WCS) supplemented at 0.65% BW daily. Pastures within the interseeded-clover and protein-supplementation treatments were fertilized with 56 kg N/ha at time of establishment. Steers were weighed every 28 d, and forage mass (FM, kg DM/ha) was measured concurrently using the destructive harvest/disk meter double-sampling method. Each of 30 0.81-ha paddocks was stocked initially with 3 “tester” steers, and stocking density (steers/ha) was adjusted using “put-and-take steers” based on changes in FM and steer BW in order to maintain a uniform forage allowance (FA) of 1 kg DM/kg steer BW. Grazing was discontinued on May 11, 2016 in Yr 1 and May 10, 2017 in Yr 2 following 140 and 84 d of grazing, respectively. Data were analyzed as a completely randomized design with repeated measures for which pasture (n = 3) was the experimental unit. Ionophore inclusion did not affect (P > 0.10) any variable measured. Mean FM differed (P < 0.0001) between years and among N-delivery methods (P < 0.10), and mean FA differed (P = 0.005) among N-delivery methods. Steer ADG differed among N-delivery methods (P = 0.02) and between years (P < 0.001), whereas total gain/ha differed (P < 0.0008) among N-delivery methods, but not between years (P = 0.78). Stocking density differed among N-delivery methods (P = 0.02) and between years (P < 0.0001), and grazing-days/ha differed between years (P < 0.0001) and among N-delivery methods (P = 0.001). Results indicate that supplementation with a high-protein by-product feed for cattle grazing annual ryegrass maintained ADG, total gain/ha and grazing-days/ha compared with N-fertilized annual ryegrass, and increased ADG, total gain/ha, and grazing-days over interseeded legumes.

187 Utilizing Working Groups to Provide Hands-On Learning Opportunities for Experienced Beef Cattle Producers

The Systems 360° Working Group program was created for experienced beef cattle producers who desired to learn more about timely topics related to beef cattle production than could be covered in a single night meeting. To aid in developing these working groups, the Alabama Extension Animal Science and Forages Team developed curriculum regarding grazing management, watering systems, marketing, handling facilities, and animal management. Regional animal science and forages agents then coordinated planned visits to producer farms and Auburn University research centers that highlighted specific management practices surrounding these topics, and facilitated group discussion at those sites to encourage peer-to-peer learning experiences. A working group consisted of beef cattle producers (n = 10–25 participants per group) sharing a common interest in learning more in-depth about strategies to improve their respective operations. Four working groups were organized in different regions of Alabama and met five times throughout 2018–2019. The closing survey (n = 50 responses) for the working groups indicated that 100% of participants felt this program met expectations, and given the opportunity they would join another working group. Overall, 94% of respondents indicated that they planned to adopt one of more of the management practices discussed in the group in the next 12 months. Top practices that producers planned to implement included improved winter grazing strategies, rotational stocking, water resource management and testing, and facilities design/animal handling. Producers indicated that they learned the most from farm-visits and speakers/discussion leaders as part of the program. Participants reported that knowledge gained from this program could potentially lead to a total farm economic impact averaging $6,095 per operation. These data indicate that Systems Working Groups are an effective means to disseminate knowledge, engage producers in peer-based learning opportunities and improve herd profitability among experienced beef cattle producers.

64 Effects of grazing cool-season cover crops on forage and animal performance

Utilization of cool-season cover crops has been shown to increase soil health and cash crop performance in minimum tillage cash crop systems. Though evidence that grazing of cover crops can be viable is limited. Our objective was to determine animal and forage performance when grazing a cool-season annual cover-crop. Twelve 1.2 ha pastures were established in a forage mix consisting of black oats (Avena strigose), cereal rye (Secale cereal), crimson clover (Trifolium incarnatum), and T-raptor (Brassica napus × B. rapa) and randomly allocated to be grazed either 0, 30, 60, or 90 days. Three tester steers were randomly placed in each paddock with the exception of control paddocks and allowed ad libitum grazing. Animals were weighed every 30 d for determination ADG and total gain (TG). Forage was harvested bi-weekly and analyzed for NDF and ADF using an ANKOM fiber analyzer (ANKOM Tech, Macedon, NY). All data were analyzed using MIXED procedure of SAS version 9.4 (SAS Inst., Cary, NC). Differences were found in ADG between 90 and 60 days grazed (4.2 ± 0.12 vs. 2.8 ± 0.12 kg/d; P &lt; 0.01) and 90 and 30 days grazed (4.2 ± 0.12 vs 2.7 ± 0.12 kg/d; P &lt; 0.01). Differences in TG were detected between 90 and 60 days grazed (819 ± 13.35 vs. 386.67 ± 13.35 kg; P &lt; 0.01), between 90 and 30 days grazed (819 ± 13.35 vs 261.33 ± 13.35 kg; P &lt; 0.01), and between 60 and 30 days grazed (386.67 ± 13.35 vs 261.33 ± 13.35 kg, P &lt; 0.01). No differences in NDF (44.86%, P = 0.99) or ADF (27.20%, P = 0.92) were detected between treatments. These results indicate that different grazing periods could influence cattle growth and performance without negatively impacting forage quality and production.

27 Defining Grazing Recommendations for Alfalfa-Bermudagrass Mixtures in the Southeastern U.S

Recently there has been growing interest in interseeding high-quality legumes, like alfalfa, into existing bermudagrass stands as a step towards improving forage, animal, and ecosystem sustainability in the Southeast. Current work evaluating these mixtures has focused on management and production of stored forages, and limited work has evaluated the use of alfalfa-bermudagrass mixtures under grazing conditions. It is known that both grazing intensity and frequency impact overall alfalfa stand production over time. The objective of this research is to evaluate the effect of harvest height and frequency on alfalfa interseeded into bermudagrass to develop grazing management recommendations. In 2018 thirty-six alfalfa-bermudagrass plots were established at 4 locations across Alabama and Georgia in a randomized complete block design with four replications at each location. Alfalfa varieties utilized were selected for suitability to location and were either ‘Bulldog 505’ or ‘Bulldog 805’ interseeded into existing hybrid bermudagrass sods. Treatments included combinations of harvest frequency (2, 4, or 6 weeks) and harvest height (5, 10, 15 cm) and plots were evaluated to determine the optimum interval in relation to sward yield, alfalfa persistence, stand density, botanical composition, nutritive value, and change over time. Forage yield was affected by the interaction of location with harvest frequency and height (P &lt; 0.05). At three of the four locations, overall seasonal yield from the 5cm cutting height was greatest; however, alfalfa persistence declined in these treatments throughout the season and was less than 10% at the northern locations when 2019 data collection began. Additionally, crude protein (CP) and in-vitro digestibility (IVDMD) declined throughout the season as the alfalfa presence decreased. This study is supported by funding from the USDA-NIFA-Alfalfa Forage Research Program (2017).

7 Assessment of beef cattle record keeping utilization and application: a collaboration of the Alabama Beef Cattle Improvement Association and the Alabama Cooperative Extension System

Beef cattle producers engaged in the Alabama Beef Cattle Improvement Association (BCIA) Commercial Record Keeping Program were surveyed to assess application of record keeping to operational management. In 2014, the specialized record-keeping system utilized by Alabama BCIA transitioned from software-based, centralized processing to an internet-based system to allow for hands-on use. The application of this new system and hands-on use was evaluated. A brief, online survey of 14 multiple-choice questions was developed. Question topics included basic demographics, value level, length of use, frequency of use, devices used, record areas, management decisions and meeting needs. The Qualtrics®XM web-based survey tool was used to evaluate results. A response rate of 44.64% was reached. Respondents represented cattlemen in business for 30+ years 44%, 20+ years 32%, 10+ years 12%, 5 to 10 years 4%, 3 to 5 years 4% and less than 3 years 4%. Cow inventory reflected 50 to 100 cows 24%, 100 to 200 cows 24%, 20 to 50 cows 20%, 200 to 300 cows 16%, 300 to 400 cows 8% and 500+ cows 8%. Longevity of BCIA record keeping reached 20 to 30 years 24%, 1 to 5 years 24%, 5 to 10 years 20%, 10 to 15 years 16%, 15 to 20 years 12% and beginning 4%. Value of performance records rated extremely valuable 72.0%, and hands-on access rated very valuable 92.0%. A majority indicated accessing the system weekly 40.0%, monthly 16.0% or daily 8.0%. The most common device was combination of computer and smartphone 36.0%. The most active record keeping areas were calving records 21.57%, weaning data 19.64% and culling cows based on performance 17.86%. Planned expansion was yearling data for replacement heifers 22.58% and collecting mature cow weights at calf weaning 20.97%. Overall, responding cattle producers indicated the internet-based system was definitely meeting their needs 88.0%.

89 Fermentation Kinetics of Different Cool-Season Annual Mixtures With or Without Silage Inoculant

High moisture feeds such as baleage are becoming a more practiced feed storage method in the Southeast due to the ability for more timely harvests and consistent forage quality compared with dry hay. The objective of this study was to determine the nutritive quality and fermentation kinetics of three different cool-season annual mixtures stored as baleage. The forage treatments were wheat (Triticum aestivum) + T-Raptor (Brassica rapa × napus; WT), wheat + crimson clover (Trifolium incarnatum; WC), and annual ryegrass (Lolium multiflorum Lam.) + oats (Avena sativa) + crimson clover (ROC) which were planted at the E.V. Smith Research Center in Shorter, AL, as a 3 × 2 × 8 factorial design (n = 3). Forage was either inoculated (I) or not inoculated (N) with a cereal/grass silage inoculant to determine its efficacy in promoting proper fermentation. Samples were taken at 8 different days after ensiling to determine fermentation kinetics and quality. Crude protein of WC was greater (P ≤ 0.005) than all other forage treatments (17.1%) and wheat + crimson clover-I was greater (P = 0.024) than WC-N (17.7 and 16.4%, respectively). However, ROC–N had greater (P = 0.033) CP than ROC–I (16.5 and 15.0%, respectively). Wheat + T-raptor ensiled with the lowest (P ≤ 0.003) pH while ROC had the greatest (P ≤ 0.001; 4.5 and 5.4, respectively). Forage treatments WC and WT did not differ (P = 0.140) in lactic acid concentration (3.7%); however, both were greater (P ≤ 0.001) than ROC (0.9%). There were no differences (P ≥ 0.128) in acetic acid concentration among all forage treatments (3.5%). The results of this study indicate that WC had the greatest nutrient quality, but do not indicate that silage inoculants offer benefits to baleage fermentation kinetics.

191 Yield and nutritive quality of summer annual forage mixtures

Summer annual forage mixtures are both high yielding and contain a high nutritive quality. They provide a summer forage option for maintaining stockers, forage-finished beef, and replacement heifers on with little to no external inputs needed. Recently, sugarcane aphid infestations have limited production of sorghum × sudangrass (Sorghum bicolor var. bicolor*bicolor var. sudanese; S). This study investigated mono-, bi-, and tri- cultures of S, cowpea (Vigna unguiculata; C), and crabgrass (Digitaria ciliaris; R). Forage yield, CP, NDF, ADF, ADL, and sugarcane aphid counts were determined for each treatment. Sugarcane aphid counts were conducted on a weekly basis during the study and forage samples were harvested twice during each season. A forage subsample was taken for determination of CP, NDF, ADF, and ADL using wet chemistry. Data were analyzed using Proc Glimmix of SAS 9.4 (SAS inst., Cary, NC). During Year 1, the only difference in yield among treatments was observed in R, which was lower than other plots (949 and 1,259 kg/ha, respectively; P &lt; 0.05). Neutral detergent fiber was greatest (P &lt; 0.0001) in treatments containing S, whereas C and C+R had the least NDF (64.6%, 55.1%, and 56.6%, respectively; P &lt; 0.02). Sugarcane aphids were greater (P &lt; 0.0001) in S+C compared to S+R and SI on July 12 (33.5, 21.1, and 22.4 aphid days/ two leaf sample, respectively). During Year 2, there were no differences in yield among plots (996 kg/ ha, P &gt; 0.9); NDF was greatest in S and lowest in plots containing C and C+R (63%, 46%, and 45.6%, P &lt; 0.0001). While there appeared to be no reduction in sugarcane aphid pressure in the mono- and mixed- cultures of S, C+R showed promise as a summer annual mixture with similar yield and higher quality to that of S and S mixtures.

9 Backgrounding system diet effects on performance of beef calves during transportation and feedyard adaptation

Nutritional management during the backgrounding phase may influence beef calf performance and ease-of-transition into the feedyard. The objective of this study was to evaluate effects of various diets on performance of calves during backgrounding, transportation, and arrival at a feedyard. In June 2019, 119 fall-born steers (n = 79, 266 ± 34 kg BW) and heifers (n = 40, 236 ± 26 kg BW) at E.V. Smith Research Center (Shorter, AL) were weaned and randomly assigned to one of four diets (3 pens per dietary treatment, 10 calves per pen): cool-season baleage (oats, annual ryegrass, and crimson clover; B), cool-season baleage and 1% BW of a commercial, high-energy grower supplement (BC), cool-season baleage and 1% BW dried distiller’s grains with solubles (DDGS; BD), or ‘Tifton 85’ bermudagrass hay and 1% BW DDGS (HD). After a 10-d acclimation period, calves began a 60-d backgrounding trial and were weighed at d 0, d 30, and d 60. There was a diet × period interaction (P = 0.0017) such that ADG decreased from 0.38 to 0.19 kg/d for calves on B, while in treatments with supplementation, calves maintained gains of 0.67 kg/d or greater into the second, 30-d period. After the end of the backgrounding trial, calves were transported to Hy-Plains Feedyard in Montezuma, KS. Calves were weighed prior to transport, immediately after transport, after 24 h rest, and 7 d on feed. Immediately after tranport, B calves had the greatest shrink (12.8%, P &lt; 0.001) compared to calves that had received supplemental feed (10.1%). After 7 d, B calves regained the lowest percentage of pre-shipping BW (93.5% weight, P &lt; 0.01) compared to calves that had received supplemental feed (96.3% weight). These data suggest that supplementing forage-based diets may provide a performance advantage during the preconditioning phase and better prepare calves for transportation and the transition into the feedyard.

68 Effects of Plant Growth-Promoting Rhizobacteria on Fall-Stockpiled Bermudagrass

Forage production practices have been greatly affected by the increasing cost of N fertilization. Therefore, supplemental and alternative N sources are needed to ensure the economic viability of these systems. A 2-yr, small plot study was designed to evaluate plant growth-promoting rhizobacteria (PGPR) as an alternative form of N fertilizer for fall-stockpiled bermudagrass (Cynodon dactylon). Eighteen 1-m2 ‘Coastal’ bermudagrass plots were treated with a synthetic N fertilizer, DH44 (PGPR strain), DH44+fertilizer, Blend 20 (PGPR blend), Blend 20+fertilizer, and a control, then stockpiled through the fall. Two PGPR applications were applied in late-August and again 30 d later. Fertilizer and PGPR+fertilizer plots received (NH4)2SO4, at a rate of 56 kg N/ha. One-third of each plot was clipped to 2.5 cm in November, December, and January, respectively. Forage DM yield, CP, NDF, ADF, and ADL were determined via wet chemistry at the Auburn University Ruminant Nutrition Laboratory (Auburn, AL). Data were analyzed using PROC MIXED (SAS 9.4, SAS Inst., Cary, NC) as a completely randomized design. Yield was greatest (P ≤ 0.0318) for Blend 20+fertilizer, but it was not different (P = 0.2552) from that of the synthetic fertilizer (1,914 kg ha-1, 1,768 kg ha-1, respectively). Concentration of CP was least (P ≤ 0.0437) for DH44 and Blend 20 treatments (90 g kg-1 and 92 g kg-1, respectively). Concentrations of NDF for the control were different (P ≤ 0.0045) for all treatments except synthetic fertilizer (P = 0.1092). Concentrations of ADF were not different (P ≥ 0.1613) excluding the control (P ≤ 0.0525; 342.8 g kg-1and 358.0 g kg-1, respectively). In vitro true digestibility (IVTD) was not different (P = 0.0947) among all treatments (463.1 g kg-1). All yield and nutritive value parameters were greater (P ≤ 0.0246) in Year 2. These results indicate that PGPR is a viable option for biofertilization of fall-stockpiled bermudagrass; however, further investigation into the effects of PGPR inoculants at a field scale are needed.

115 Nitrogen fertilizer effects on above ground sward characteristics and beef heifer performance from native warm-season grass blends

A 2-yr study was conducted at Black Belt Research and Extension Center in Marion Junction, AL, to evaluate the effect of nitrogen (N) fertilizer application rate on forage production characteristics, nutritive value, and animal performance of beef heifers grazing a mixture of native warm-season grasses (NWSG) including big bluestem, little bluestem, and indiangrass. Six, two-hectare plots were randomly assigned to one of two treatments (0 or 67 kg N ha-1 applied in early April; n = 3 replications per treatment). Paddocks were continuously stocked with four weaned Angus × Simmental beef heifers (initial BW 288 ± 7 kg) from late May/early June through mid-to-late August during 2018 (73 grazing d) and 2019 (70 grazing d), respectively. Put-and-take cattle were used to manage forage to a target of 38 cm. Forage mass and canopy heights were collected every two weeks during the trial. Visual ground cover ratings, canopy light interception, and botanical composition were measured at the beginning and end of the trial in each year. Hand-plucked samples were collected every two weeks during the grazing trial to determine forage nutritional value. Data were analyzed using the PROC MIXED procedure in SAS 9.4, and differences were declared significant when P ≤ 0.05. Nitrogen fertilized NWSG had greater crude protein (P &lt; 0.0001), sward heights (P = 0.0003), and canopy light interception at the beginning of the season (P = 0.0049) compared to non-fertilized paddocks. However, there were no differences (P ≥ 0.05) among N-fertility treatments for mean forage mass, heifer ADG, or BCS across the 2-yr study. Botanical composition data indicated that indiangrass decreased from 64% to 61% (P = 0.0022) and weed pressure increased from 11% to 15% (P = 0.0064) across the summer grazing season. Canopy light interception decreased by 51% from early June to August in fertilized NWSG and 26% in unfertilized paddocks, respectively. These data illustrate that NWSG systems may provide a viable grazing system in the summer months under reduced N inputs.

65 Effects of grazing cool-season cover crops on forage and animal performance

Utilization of cool-season cover crops has been shown to increase soil health and cash crop performance in minimum tillage cash crop systems. Though evidence that grazing of cover crops can be viable is limited. Our objective was to determine animal and forage performance when grazing a cool-season annual cover-crop. Twelve 1.2 ha pastures were established in a forage mix consisting of black oats (Avena strigose), cereal rye (Secale cereal), crimson clover (Trifolium incarnatum), and T-raptor (Brassica napus × B. rapa) and randomly allocated to be grazed either 0, 30, 60, or 90 days. Three tester steers were randomly placed in each paddock with the exception of control paddocks and allowed ad libitum grazing. Animals were weighed every 30 d for determination ADG and total gain (TG). Forage was harvested bi-weekly and analyzed for NDF and ADF using an ANKOM fiber analyzer (ANKOM Tech, Macedon, NY). All data was analyzed using MIXED procedure of SAS version 9.4 (SAS Inst., Cary, NC). Differences were found in ADG between 90 and 60 days grazed (4.2 ± 0.12 vs. 2.8 ± 0.12 kg/d; P &lt; 0.01) and 90 and 30 days grazed (4.2 ± 0.12 vs 2.7 ± 0.12 kg/d; P &lt; 0.01). Differences in TG were detected between 90 and 60 days grazed (819 ± 13.35 vs. 386.67 ± 13.35 kg; P &lt; 0.01), between 90 and 30 days grazed (819 ± 13.35 vs 261.33 ± 13.35 kg; P &lt; 0.01), and between 60 and 30 days grazed (386.67 ± 13.35 vs 261.33 ± 13.35 kg, P &lt; 0.01). No differences in NDF (44.86%, P = 0.99) or ADF (27.20%, P = 0.92) were detected between treatments. These results indicate that different grazing periods could influence cattle growth and performance without negatively impacting forage quality and production.

Cow-calf performance, forage utilization, and economics of warm-season annual baleage in beef cattle winter feeding systems

A 52-d winter feeding trial was conducted to determine animal performance, utilization, and economics of pearl millet (PM) baleage, sorghum × sudangrass (SS) baleage, and "Tifton 85" bermudagrass (B) hay for lactating beef cow-calf pairs. Cone (C) and open-shaped (O) rings were evaluated for potential to minimize forage wastage. The experiment was a completely randomized design with a 3 × 2 factorial arrangement of treatments for each forage type × hay ring (3 cow-calf pairs per treatment; 2 replications per treatment). Animal response measures included cow body weight (BW) change and body condition score (BCS) over the 52-d trial, initial and final calf BW, and cow milk production at the midpoint and end of the study. Forage nutritive value parameters evaluated for each forage type included ash, crude protein (CP), in vitro true digestibility (IVTD), neutral detergent fiber (NDF), acid detergent fiber, and acid detergent lignin (ADL). Forage wastage was estimated for each forage × ring treatment as the percentage of the bale weight remaining in feeding rings at the time of bale replacement. An economic evaluation of the relative costs associated with production and utilization of each forage type was calculated. There were no differences (P ≥ 0.10) in cow BW change or BCS change among forage types, between ring shapes, or an interaction observed for these response variables. Proportion of waste from PM and SS baleage was greater (P < 0.10) than for B hay, although there was no forage type × hay ring interaction or differences between O and C hay ring treatments for forage waste (P ≥ 0.10, respectively). Cow milk production and calf BW gain did not differ among forage type (P ≥ 0.10, respectively); however, beef calves in pens containing the O ring feeder weighed 6 kg more (P ≤ 0.05) than calves whose dams were fed using C rings. The economic analysis implies that it is more costly to feed warm-season annual forage baleage to cow-calf pairs than dry hay, largely due to greater costs of production, lack of difference in animal performance responses, and less utilization of baleage compared with feeding bermudagrass hay in this trial.

61 2018 Southern Section Extension Forum: Collaborating to meet the needs of clientele

A two-day forum was held at the University of Tennessee (UT) Middle Tennessee Research and Education Center to foster collaborative efforts between Extension specialists and county or area agents across the southern United States. The forum was attended by 28 specialists and 18 county or regional agents from across the Southern Section of ASAS. The forum began with a tour of the UT Heifer Development Center. The forum was split into three sessions and included: 1. Transfer of knowledge (Demonstration research), 2. Developing formal education for Extension agents, and 3. Collaborating across state lines to develop Extension Programs. Within each section, a brief presentation was given, followed by break-out sessions to discuss success stories from each state and potential programs to implement. From the break-out session, areas of need identified primarily focused on the development of support resources for Extension agents. Needed outputs identified included a resource guide for conducting on-farm research and demonstration projects with county and regional Extension agents, defining a regional process to provide formal distance education for agents, and development of online coursework and training tools for agents for continuing education. Assessment data indicate that participants had completed an average of 8.4 (± 6.65, range 0.5 to 24) years of service. Agents were asked to rank their level of confidence, using a 5-point Likert scale, with three tasks. Averages (SEM) of that self-assessment are indicated in Table 1. The 2018 Southern Section Extension Forum was a successful effort to bring together collaborators to identify needs and propose programs to improve the impact of Extension.

Collapse

156 Effect of shipping stress on complete blood counts of backgrounded beef steers

The objective of this study was to quantify the effect of shipping to feedyards in western Kansas from the Southeast on the immune response of beef steers using complete blood counts. Angus- and Hereford-sired steers (n = 24, BW = 266.3±24.9 kg) from E.V. Smith Research Center in Shorter, AL, were weaned on June 14, 2018. The following day, blood was collected for analysis. These calves were a subset from a larger project involving grazing. As such, calves were then maintained in drylots for 14 d until grazing was available. Once grazing was initiated, these calves were placed in drylot pens with a diet consisting of dry hay with supplemented with 1% of BW of dried distiller’s grains with solubles. After 80 d, half of the calves were shipped (n = 12, SC) to Hy-Plains Feedyard, LLC. in Montezuma, KS. Immediately prior to shipment, immediately post-shipment, and after 24-hr rest, blood was collected. Blood was also collected from the unshipped calves (UC) at similar time points. Whole blood collected at each time point was analyzed for complete blood counts. The data was analyzed using the Mixed Procedure in SAS. No significant differences (P > 0.05) were detected post-weaning or pre-shipping. Immediately post-shipment, white blood cell, and neutrophil counts were greater in SC while lymphocytes counts were less (P < 0.05) than UC; however, these were not different after 24-hr rest (P > 0.05). Hematocrit and monocyte count were elevated in SC both immediately post-shipping and after 24 hr of rest (P <0.05), while reticulocyte count was lower in SC at those same time points (P < 0.05). Basophil counts were lower in SC at the 24-hr rest time point (P = 0.03). Results of this study indicate that SC did not completely rehydrate after 24 hr of rest and complete blood counts show differences in immune response due to shipping

110 Effect of different backgrounding diets for weaning beef calves on complete blood counts pre and post shipping

The objective of this study was to evaluate if diet during the background phase has an effect on complete blood counts as an indicator of the stress response and immune function of calves shipped to feedyards in western Kansas from the Southeast. One hundred twenty (n = 120) Angus- and Hereford-sired steers (n = 60, 237.9±21.6 kg BW) and heifers (n = 60, 227.6±17.9 kg BW) from the E.V. Smith Research Center in Shorter, AL, were weaned on June 14, 2018. The following day, calves were weighed and blood was collected for analysis. Calves were then held in drylots for 14 d until forages reached an adequate height to begin grazing. Calves were then stratified by weight and randomly assigned to four dietary treatments, with three pens per treatment: Grazing (G), Grazing with supplement (GS), dry hay with supplement (HS), or baleage with supplement (BS). Dried distiller’s grains with solubles fed at 1% of BW was used in each diet including supplementation. After 80 d on treatment diets, calves were shipped to Hy-Plains Feedyard, LLC. in Montezuma, KS. Immediately prior to shipment, immediately post-shipment, and after 24 hr rest, blood was collected for analysis. Whole blood collected at each of the four times points was analyzed for complete blood counts using a ProCyte Dx Hematology Analyzer. The data were analyzed using the Mixed Procedure in SAS. While no significant differences (P > 0.05) were detected post-weaning and prior to initiation of dietary treatments, differences across diets were seen in red blood cell count, hemoglobin, hematocrit, reticulocyte count, platelet count, white blood cell count, neutrophil count, lymphocyte count, neutrophil to lymphocyte ratio, and basophil counts (P < 0.05). Results of this study show that post-weaning backgrounding diets can have an effect on immune response to shipping stress

97 Nutritive value and fermentation characteristics of cool-season annual baleage

Baleage production is gaining popularity in the Southeast due to the ability for more timely harvests and more consistent forage quality compared with hay. The objective of this study was to determine the feasibility of cool-season mixtures for baleage production. Wheat (Triticum aestivum) with T-Raptor (Brassica rapa × napus; WT) or crimson clover (Trifolium incarnatum; WC) were planted at the E.V. Smith Research Center in Shorter, AL as a 2 × 2 factorial design (n = 3). Forage was treated or un-treated with silage inoculant to determine its efficacy in promoting proper fermentation. Samples were taken at 7 different time intervals to determine fermentation characteristics and quality. There was no difference (P ≥ 0.15) in ADF concentration among treatments, but day 120 after ensiling was greater (P ≤ 0.002) than all other sampling dates. There was no difference (P ≥ 0.11) in NDF between forages, silage inoculants, or among days and averaged 50.75%. The CP of the WC treatment was greater (P ≤ 0.0001) than WT by 3.6 units. Inoculated forage was greater (P ≤ 0.0001) than non-inoculated by 1.06 units. Crude protein was greater (P = 0.005) on day 120 than day 0. Inoculated WT had greater (P < 0.0001) total acid content than non-inoculated (8.35 vs. 6.19%, respectively). Wheat+clover had 1.5 units more total acid than WT. Inoculated forage had greater (P ≤ 0.0006) total acid present than non-inoculated forage. Butyric acid concentration increased (P ≤ 0.0001) with increasing days after ensiling. Butyric acid tended to be greater (P = 0.05) in WC than WT, likely due to increased pH in clover treatments as a result of legume buffering capacity. The results indicate that silage inoculants offer minimal benefits to baleage fermentation when using cool-season annual mixtures

67 2018 Alfalfa in the South Workshop Series: A review of regional Extension efforts

Alfalfa research in the Southeast has steadily increased over the past ten years. Researchers have a renewed interest in this perennial legume as new varieties have been released that are better suited to the challenging climate and use in the Southeast. Extensive effort has been put forth in establishing programs promoting the use of alfalfa as a viable high-quality forage option in the south. In 2018, the “Alfalfa in the South” workshop series was designed to provide in-depth extension education, circulate new research findings, and engage in discussions with producers as related to the use of alfalfa in the southeast. The series consisted of 4 one-day workshops, organized by University of Georgia Extension in conjunction with America’s Alfalfa, and included Extension specialists, faculty, and graduate students from both the University of Georgia and Auburn University. Topics were broken into five classroom learning modules: 1) site selection and establishment, 2) improving animal performance with alfalfa, 3) managing alfalfa for persistence, 4) alfalfa breeding programs, and 5) graduate student research updates. Each workshop concluded with an on-farm demonstration where attendees engaged in discussion with producers utilizing alfalfa in their operation. Postworkshop evaluation results determined that, on a scale of 1 to 5, where “1” was “no change” and “5” indicated “greatly improved,” producers rated their change in interest using alfalfa as a 4.73 and their confidence in using alfalfa management skills as 4.36. Additionally, the producer discussion and field tour section rated the highest, 4.67 (1 being “poor” and 5 being “excellent”); however, all topics rated 4.12 or higher, indicating that attendees found this workshop to be very good to excellent. Of the 60 participants, 68% indicated that they would make some major changes and 32% plan to try to make minor management changes following the workshops.

146 Evaluation of plant growth promoting rhizobacteria on stockpiled bermudagrass

Plant growth-promoting rhizobacteria (PGPR) are non-pathogenic, soil-inhabiting, beneficial bacteria that colonize the roots of plants. Some PGPR strains are reported to increase nutrient uptake and fix atmospheric N, which suggests that biofertilization with PGPR may provide an alternative to N fertilization for forage production. In mid-August 2017, a study was initiated to evaluate PGPR as an alternative form of N fertilization for fall-stockpiled bermudagrass. Eighteen 1-m2plots were mowed to a 2.5-cm stubble height prior to stockpiling. Two strains of PGPR (Blend 20 and DH44) were selected for evaluation based on performance in greenhouse trials. Treatments included: control, fertilizer, DH44, DH44+fertilizer, Blend 20, and Blend 20+fertilizer (n = 3).Two applications of PGPR were applied at the beginning of the stockpiling season and 30 d later. Ammonium sulfate was applied at 56 kg/ha during the first PGPR application. Plots were clipped to a height of 2.5 cm in mid-November, December, and January to determine yield and nutritive value. Data were analyzed using PROC MIXED (SAS 9.4) as a completely randomized design.Yield was greater (P ≤ 0.007) for Blend 20+fertilizer, DH44, and Blend 20 (695, 673, and 664 kg DM/ha, respectively) than the control (598 kg DM/ha). Forage DM yield differed among harvest dates, with Blend 20+Fertilizer having the highest yield in January (835 kg DM/ha). Blend 20+fertilizer, control, and fertilizer treatments had the greatest effect on CP concentration (9.1, 9.5, and 10.1%, respectively). Concentrations of NDF and ADF were greatest (P ≤ 0.01) for Blend 20, Blend 20+fertilizer, DH44, and fertilizer. Percentage IVTD decreased with the later harvests (46.1, 33.8, and 39.0% in November, December, and January, respectively); however, CP was unchanged across all harvests (P3 0.12). Overall, PGPR increased DM yield of stockpiled bermudagrass while maintaining forage nutritive value similar to commercial fertilizer.

202 In vitro digestibility of various browse species selected by goats over the growing season

Goats naturally prefer to consume browse species given the choice. Browsing away from the ground may help avoid internal parasites; however, goats cannot consume more than 50% of their diet as browse due to the prevalence of toxins in the browse species. The objective of this project was to determine in vitro true digestibility (IVTD) of preferred browse species consumed by goats at Tuskegee University browsing demonstration site over the growing season. Three samples were collected from each of the 35 different browse species in April and July 2018. Samples consisted of leaves and edible twigs. Browse IVTD was determined according to the Van Soest et al. (1991) modification of the Tilley and Terry (1963) procedure using the Ankom Daisy II incubator system. Data were analyzed for the months of April and July utilizing the two-sample T-test of SYSTAT, Version 13. Browse IVTD values differed (Pteridium aquilinum (Brakenfern) to 94.7% in Phytolacca americana (pokeweed) while the July values ranged from 33.59% in Pteridium aquilinum to 88.5% for Morus rubra (Mulberry). Significant differences were also observed among browse species with regards to dry matter content. Dry matter content values ranged from 10.5 (Albizia julibrissin; White mimosa) to 81% (Prunus americana; American Plum) in April and 12.5 Phytolacca americana to 89% Pinus taeda (Loblolly Pine) in July. Results showed natural variability in IVTD of various browse species throughout the growing season. Future experiments will analyze additional nutritive value parameters such as ADF, NDF, total digestible nutrients, and lignin values over three collection times (April, July, and October). The experiment will be continued for two additional years to provide meaningful results.

139 Evaluation of cool-season annuals or reduced labor supplementation systems for wintering cowcalf pairs

Cattle producers typically feed hay and supplement for a 90- to 120-d window to maintain cows during the winter in Alabama. Relying on stored feeds can increase management system costs and labor needs. The objective of this demonstration project was to compare alternative, reduced labor management systems commonly used by producers in the region for diet quality and animal performance responses. A 75-day trial evaluated the use of three systems (n = 3 replications per system): 1) rotationally grazed-winter annuals (GWA) on a 14-day rotation, 2) free-choice whole cottonseed (WCS) and bermudagrass hay, or 3) 50% soybean hulls and 50% corn gluten feed (SH:CGF) fed on alternate days at up to 1% BW daily and free-choice bermudagrass hay. GWA had the greatest diet digestibility (P < 0.0001), and SH:CGF and WCS were not different from one another (88.7%, 64.3%, and 64.6%, respectively). Diet CP values differed (P < 0.0001) for WGA (21.5%), SH:CGF (13.1%), and WCS (11.2%), respectively. Initial and final cow BCS was not different among treatments (P = 0.1558). Cow ADG was greater (P = 0.0370) on GWA than SH:CGF and WCS (0.9, 0.2, and 0.2 kg, respectively), and calf ADG followed a similar pattern (1.5, 1.2, and 1.1 kg/day for GWA, WCS, and SH:CGF, respectively). This project demonstrates that winter annuals provided 75 days of high-quality winter grazing and resulted in greater animal performance than the other diets. However, all diets provided reduced labor options to maintain cows throughout the winter.

99 Managing alfalfa-bermudagrass mixtures in the Southeastern U.S. to establish livestock grazing recommendations

Recently there has been interest in interseeding high-quality legumes, like alfalfa, into existing bermudagrass stands as a step towards improving forage, animal, and ecosystem stability in the Southeast. Current work evaluating these mixtures has been focused on management and production of stored forages (i.e. dry hay/baleage), and limited work has evaluated the use of alfalfa-bermudagrass mixtures under grazing conditions. It has been noted that both grazing intensity and frequency impact overall stand production over time. The objective of this research is to evaluate the effect of harvest height and frequency of newly established alfalfa interseeded into an existing bermudagrass stand, and begin to develop grazing recommendations for management of these mixtures. In 2018, 36 alfalfa-bermudagrass plots were established at 4 locations across Alabama (Crossville, Shorter) and Georgia (Watkinsville, Tifton), using a randomized complete block design with four replications at each location. Alfalfa varieties were selected for suitability to location and were either ‘Bulldog 505’ or ‘Bulldog 805’ interseeded into existing hybrid bermudagrass sods. Treatments included combinations of harvest frequency (2, 4, or 6 wk) and harvest height (2, 4, 6 inches), and plots were evaluated for their influence on sward yield, persistence, stand density, botanical composition, nutritive value, and change over time. In Georgia, the ‘Bulldog 805’ treatment harvested every 6 weeks at 6 inches had the greatest yield on average (2,453 kg/ha), while ‘Bulldog 505’ treatment harvested every 2 weeks at 6 inches had the lowest yield on average (382 kg/ha) during the 2018 growing season. Additionally, botanical compositions showed that the 6 week, 4-inch had the greatest proportion of alfalfa throughout the growing season, while alfalfa proportions decreased across the growing season in the 2 week, 2-inch harvest treatment. This study is supported by funding from the USDANIFA-Alfalfa Forage Research Program (2017)

5 Nutritive value and fermentation characteristics of cool-season annual baleage

Baleage production is gaining popularity in the Southeast due to the ability for more timely harvests and more consistent forage quality compared with hay. The objective of this study was to determine the feasibility of cool-season mixtures for baleage production. Wheat (Triticum aestivum) with T-Raptor (Brassica rapa × napus; WT) or crimson clover (Trifolium incarnatum; WC) were planted at the E.V. Smith Research Center in Shorter, AL, as a 2 × 2 factorial design (n = 3). Forage was treated or un-treated with silage inoculant to determine its efficacy in promoting proper fermentation. Samples were taken at 7 different time intervals to determine fermentation characteristics and quality. There was no difference (P ≥ 0.15) in ADF concentration among treatments, but day 120 after ensiling was greater (P ≤ 0.002) than all other sampling dates. There was no difference (P ≥ 0.11) in NDF between forages, silage inoculants, or among days and averaged 50.75 %. The CP of the WC treatment was greater (P ≤ 0.0001) than WT by 3.6 units. Inoculated forage was greater (P ≤ 0.0001) than non-inoculated by 1.06 units. Crude protein was greater (P = 0.005) on day 120 than day 0. Inoculated WT had greater (P < 0.0001) total acid content than non-inoculated (8.35 vs. 6.19 %, respectively). Wheat+clover had 1.5 units more total acid than WT. Inoculated forage had greater (P ≤ 0.0006) total acid present than non-inoculated forage. Butyric acid concentration increased (P ≤ 0.0001) with increasing days after ensiling. Butyric acid tended to be greater (P = 0.05) in WC than WT, likely due to increased pH in clover treatments as a result of legume buffering capacity. The results indicate that silage inoculants offer minimal benefits to baleage fermentation when using cool-season annual mixtures

Fiber digestion kinetics and protein degradability characteristics of stockpiled Tifton 85 bermudagrass

A 2-yr study was conducted to determine effects of N fertilization level on fiber digestion kinetics and protein degradability characteristics of stockpiled Tifton 85 bermudagrass (T85). Six 0.76-ha pastures of stockpiled T85 were cut to a 10-cm stubble height on August 1 of each yr and fertilized with 56 (56N), 112 (112N), or 168 (168N) kg N/ha (2 pastures/treatment). Fiber digestion kinetics included the 72-hr potential extent of NDF digestion (PED), rate of NDF digestion, and lag time. In yr 1 and 2, PED decreased over the stockpile season. Rates of NDF digestion did not differ ( > 0.05) among N fertilization treatments in either yr. In yr 1, rate of NDF digestion was greatest ( < 0.05) in October/November, and decreased beginning in December. In yr 2, rate of NDF digestion decreased ( < 0.05) in January compared with November, but digestion rates were similar for November and January 21 sampling dates. Lag time was greater ( < 0.05) for the 112N than 56N and 168N treatments, and increased ( < 0.05) across sampling dates in yr 1. In yr 2, lag time increased ( < 0.05) from 9.0 to 17.7 h across the season. In yr 1 and 2, a negative correlation ( < 0.05) between forage lignin concentration and both PED ( = -0.91 and -0.87 in yr 1 and 2, respectively) and rate of NDF digestion ( = -0.60 and -0.25 in yr 1 and 2, respectively) was observed. There was a trend ( = 0.06) for lignin concentration to be positively correlated with lag time ( = 0.39) in yr 1, and a strong relationship was observed in yr 2 ( = 0.91; < 0.05). The RDP fraction as a % of CP was ≥ 90% throughout both years. Concentration of RDP (% of total DM) decreased across the stockpiling season through January in yr 1 and 2. Results suggest that kinetic parameters of NDF digestion in stockpiled T85 were influenced more by temporal changes over the stockpile season than by N fertilization level. Supplement formulations based on kinetic parameters of fiber digestion may require periodic adjustment to insure that energy-yielding components of NDF are sufficient to meet animal requirements throughout the stockpile season. The CP fraction in stockpiled T85 contains sufficient RDP to support fibrolytic activity and growth of ruminal microorganisms throughout the stockpile season. Toward the latter end of the season, supplementation with sources of digestible fiber and RDP could be expected to increase MP supply to the host animal.

Stockpiled Tifton 85 bermudagrass for backgrounding stocker cattle

A 2-yr grazing trial was conducted to evaluate the use of conserved forage type, stockpiled Tifton 85 bermudagrass ( L.; T85) or T85 hay, and supplement type for stocker cattle during the fall forage deficit in the southeastern United States. The study site consisted of six 0.75-ha paddocks of stockpiled T85 for grazing and six 0.20-ha drylot paddocks for feeding T85 hay. Steers ( = 5 per paddock; mean initial BW for both yr, 263 ± 30 kg) were randomly assigned to paddocks on November 11, 2014 and October 28, 2015 in yr 1 and yr 2, respectively. Treatments included T85 hay or stockpile (control), T85 hay or stockpile plus 0.2 kg cottonseed meal and 0.7 kg soybean hulls∙steer∙d (SUPPL1), or 0.45 kg cottonseed meal and 0.45 kg soybean hulls∙steer∙d (SUPPL2). Polytape fencing was used for frontal grazing stockpiled T85 paddocks to allocate a 3- to 4-d allotment of forage DM for the animals based on available forage mass and steer DMI requirements. There were no differences among treatments ( > 0.10) in mean pregrazing forage mass across sampling dates (5,099 kg DM/ha and 7,998 kg DM/ha in yr 1 and yr 2, respectively), forage allowance (1.9 kg DM/kg steer BW and 3.0 kg DM/kg steer BW in yr 1 and yr 2, respectively) and forage utilization (84% and 88% in yr 1 and yr 2, respectively). No differences ( > 0.10) were detected for nutritive value parameters CP, ADF, NDF, and TDN among stockpiled T85 treatments in both yr. However, there were differences across sampling dates ( < 0.0001) for stockpiled T85 such that forage quality generally declined as the grazing season progressed in both yr. Steers fed T85 hay had greater final BW and ADG ( = 0.018) than those grazing stockpiled T85. Mean final BW and ADG of steers grazing T85 stockpile or fed hay with no supplementation was less ( = 0.020) than those receiving supplementation. Steers grazing stockpiled T85 had decreased ADG in the second half of the grazing season in both yr of the study, which is a result of declining forage nutritive value as the stockpiling season progressed. Results indicate that stockpiled T85 supplemented with CP and energy can support stocker cattle at a maintenance level, but to achieve a target gain of 0.9 kg/day would require a greater level of supplementation to overcome decreasing forage nutritive value dynamics.