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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 (P> 0.05) among N fertilization treatments in either yr. In yr 1, rate of NDF digestion was greatest (P< 0.05) in October/November, and decreased beginning in December. In yr 2, rate of NDF digestion decreased (P< 0.05) in January compared with November, but digestion rates were similar for November and January 21 sampling dates. Lag time was greater (P< 0.05) for the 112N than 56N and 168N treatments, and increased (P< 0.05) across sampling dates in yr 1. In yr 2, lag time increased (P< 0.05) from 9.0 to 17.7 h across the season. In yr 1 and 2, a negative correlation (P< 0.05) between forage lignin concentration and both PED (r= -0.91 and -0.87 in yr 1 and 2, respectively) and rate of NDF digestion (r= -0.60 and -0.25 in yr 1 and 2, respectively) was observed. There was a trend (P= 0.06) for lignin concentration to be positively correlated with lag time (r= 0.39) in yr 1, and a strong relationship was observed in yr 2 (r= 0.91; P< 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.

In novel, low-speed sedimentation assays, highly purified, sonicated Dictyostelium discoideum plasma membrane fragments bind to F-actin beads (fluorescein-labeled F-actin on antifluorescein IgG-Sephacryl S-1000 beads). Binding was found to be (a) specific, since beads containing bound fluorescein-labeled ovalbumin or beads without bound fluorescein-labeled protein do not bind membranes, (b) saturable at approximately 0.6 microgram of membrane protein per microgram of bead-bound F-actin, (c) rapid with a t1/2 of 4-20 min, and (d) apparently of reasonable affinity since the off rate is too slow to be measured by present techniques. Using low-speed sedimentation assays, we found that sonicated plasma membrane fragments, after extraction with chaotropes, still bind F-actin beads. Heat-denatured membranes, proteolyzed membranes, and D. discoideum lipid vesicles did not bind F-actin beads. These results indicate that integral membrane proteins are responsible for the binding between sonicated membrane fragments and F-actin on beads. This finding agrees with the previous observation that integral proteins mediate interactions between D. discoideum plasma membranes and F-actin in solution (Luna, E.J., V. M. Fowler, J. Swanson, D. Branton, and D. L. Taylor, 1981, J. Cell Biol., 88:396-409). We conclude that low-speed sedimentation assays using F-actin beads are a reliable method for monitoring the associations between F-actin and membranes. Since these assays are relatively quantitative and require only micrograms of membranes and F-actin, they are a significant improvement over other existing techniques for exploring the biochemical details of F-actin-membrane interactions. Using F-actin beads as an affinity column for actin-binding proteins, we show that at least 12 integral polypeptides in D. discoideum plasma membranes bind to F-actin directly or indirectly. At least four of these polypeptides appear to span the membrane and are thus candidates for direct transmembrane links between the cytoskeleton and the cell surface.

The binding between sonicated Dictyostelium discoideum plasma membrane fragments and F-actin on Sephacryl S-1000 beads was found to be competitively inhibited by myosin subfragment-1. This inhibition is MgATP-sensitive, exhibits a Ki of approximately 5 X 10(-8) M, and is reciprocal, since membranes inhibit the binding of 125I-heavy meromyosin to F-actin on beads. These experiments demonstrate that membrane binding and S-1 binding to F-actin on beads are mutually exclusive and, therefore, that the membrane fragments bind predominantly to the sides, rather than to the ends, of the actin filaments. This conclusion is supported by electron micrographs that show many lateral associations between membrane fragments and bead-associated actin filaments. Such lateral associations could play an important role in the organization and lateral movement of membrane proteins by the cytomusculature.

Regions of plasma membrane involved in Dictyostelium discoideum intercellular adhesion resist solubilization with the nonionic detergent Triton X-100. Electron microscopy shows that these regions of the plasma membrane adhere to each other, forming many bi- and multilamellar structures. NaDodSO4/polyacrylamide gels of these regions contain major polypeptides at 225 kDa (residual myosin), 105 kDa, 88 kDa, 84 kDa, 47 kDa (residual actin), and 34 kDa. These membranes contain a subset of the total plasma membrane proteins, as analyzed by labeling of electrophoretically fractionated and blotted membrane proteins with radioiodinated Con A and by electrophoresis of membrane proteins from surface-labeled cells. Antibodies specific for gp80, a glycoprotein implicated in intercellular adhesion, intensely stain the 88-kDa and 84-kDa bands. Since these membrane regions resist Triton extraction, they appear to be stabilized by protein-protein interactions. Such stabilizing interactions may involve multivalent linkages with adjacent cells, or associations with intracellular actin and myosin, or both. Since these membranes appear to represent regions of intercellular contact, we call them "contact regions."

The Southeast Women’s Cattle Handling program was designed to promote self-confidence for women by providing hands-on educational opportunities and cattle handling skills implementing Beef Quality Assurance methods and promoting farm safety. The two-day, hands-on workshop was conducted by Alabama Cooperative Extension educators, local veterinarians, and producers. Participation was limited to 20 females in order to allow time for participants to practice the techniques taught by instructors. Applicants were asked to indicate the reason they would like to attend the workshop via an electronic questionnaire. Of the 26 applicants, 20 responded and indicated that they had either found themselves involved in the family farm through marriage (15%) or as the sole operator through inheritance (20%), the death of a spouse (20%), or chose to purchase their own operation (45%). Topics included 1) keeping reproductive/vaccination records, 2) vaccination techniques, 3) truck & trailer safety/hauling, 4) BQA certification training, 5) tractor & equipment safety, 6) forage species, 7) forage analysis & interpretation, 8) forage pests & management, 9) reproduction & dystocia, and 10) supplementing the cow herd. A pre and post-test was administered to participants (n =19) in order to compare participants’ knowledge before and after the workshop. Comparison of answers using paired t-test showed an increase (P< 0.01) from pre-test (63.5%) to post-test (88.5%) knowledge. A BQA certification pre and post-test was administered to participants (n = 19), which showed an increase (P< 0.01) in passing scores from pre-test (83.2%) to post-test (93.7%). Participants completed an impact evaluation at the conclusion of the workshop where they indicated the probability of implementing the following concepts learned (mean values ± standard deviation) as a result of this program (1 = no; 2 = maybe; 3 = yes; 4 = already doing): keep vaccination/reproductive records (3.6 ± 0.51), use proper vaccination techniques (3.6 ± 0.51), assess truck and trailer before hauling (3.2 ± 0.94), apply low stress handling techniques (3.4 ± 0.51), maintain BQA certification (2.8 ± 0.55), manage forage for quality & pests (3.2 ± 0.43), assess your cow herd using 7 quality checks (3.1 ± 0.24), and forage test (2.9 ± 0.58). The total number of hectares of pasture owned and total number of cattle owned was 1014.5 ha and 1128 hd, respectively. In total, 100% of the participants stated the workshop met their expectations and would recommend this workshop to others.

The Southern Section Extension Forum was held in Ardmore, OK in August 2015. The objective of this two-day conference was for state and regional area Extension specialists to network with industry and producers to discuss current issues related to the development and delivery of forage-livestock programming within the southeastern region. This Forum was well attended by 49 total participants from Alabama, Arkansas, Florida, Georgia, Kentucky, Mississippi, North Carolina, Oklahoma, South Carolina, and Texas. Topics included preparedness when working with news reporters, marketing programs, program evaluation, and quantifying program impact. There were also a series of panel discussions focused on new agent training, industry perspectives on Extension programming, and funding challenges/opportunities. With all 24 survey responses indicating yes or maybe, participants felt the information presented would be useful in Extension programming. Participants were asked to rate topics and speakers on a Likert-type scale, where 1= poor and 5 = excellent. Participants rated the talks on interviews with media and marketing programs and services with highest topic scores, both at 4.38 ± 0.72. The lowest score of all topics was 3.52. Participants indicated that the program length of 2 half-day sessions with an optional tour was ideal for the program (19 of 24 responses), and that the program should be repeated every 2 or 3 years (11 and 10 responses, respectively). Presentations were the preferred format for content delivery, and ranked first by 10 out of 23 responses; however open response indicated a desire for more panel and open discussion. Program attendee demographics indicated that those in attendance were primarily focused on beef cattle (19), followed by forage (8), small ruminants (4), equine (3), dairy (2), and swine (1). The majority of attendees (58%) focused on general management and nutrition. The time in current position for attendees ranged from 2 months to 30 years, with an average of 8 years, which helped facilitate high-quality group discussion across varying levels of experience. Attendees indicated a planned adoption or increased adoption of social media in Extension programs. Overall the forum was well received and considered a success by attendees.