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Despite hay's significance as a driver of the agricultural economy and its role as a major input into the livestock sector, it has generally received less attention in marketing literature than many other commodities. This work examined sale results from a hay auction in Central Kentucky where information on hay weights and quality were made available to prospective buyers prior to sale. Utilizing this data, a hedonic analysis was employed to examine specific factors that impacted sale prices for individual lots of hay. This work built on existing literature by evaluating the price impact of large round bales compared to small square bales, hay quality measures of Total Digestible Nutrients (TDN) and Relative Feed Value (RFV), lot size, and bale weight. Hay sold in small square bales was found to net a significantly higher price than hay sold as large round bales, even when holding other factors constant. This work also confirmed the importance of hay quality measures as a price driver, even in a market environment without significant dairy influence. Finally, quantitative evidence was found to support a negative relationship between price and small square bale weight, such that price and revenue would likely decrease as small square bales become larger. This work has implications for producers and sellers of hay as they consider marketing strategies and hay buyers as they attempt to understand what drives prices of hay in their region. [ABSTRACT FROM AUTHOR]

Previous research has indicated that serotonergic and α-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+; Epichlöe coenophialia) tall fescue (Lolium arundinaceum). The objective of this experiment was to determine the period of time necessary for the vascular effects of ergot alkaloids to subside. Two experiments were conducted to investigate changes in vascular contractile response and vasoconstriction over time relative to removal from an ergot alkaloid-containing E+ tall fescue pasture. In Experiment 1, lateral saphenous vein biopsies were conducted on 21 predominantly Angus steers (357 ± 3 kg body weight) at 0 (n = 6), 7 (n = 6), 14 (n = 5), or 28 days (n = 4) after removal from grazing pasture (3.0 ha; endpoint ergovaline + ergovalinine = 1.35 mg/kg DM) for 126 days. In Experiment 2, lateral saphenous veins were biopsied from 24 Angus-cross steers (361 ± 4 kg body weight) at 0, 21, 42, and 63 days (n = 6 per time point) following removal from grazing tall fescue pastures (3.0 ha; first 88 days endpoint ergovaline + ergovalinine = 0.15 mg/kg DM; last 18 days endpoint ergovaline + ergovalinine = 0.57 mg/kg DM) for 106 total days. Six steers (370 ± 18 kg body weight) off of bermudagrass pasture for the same time interval were also biopsied on Day 0 and Day 63 (n = 3 per time point). Additionally, in Experiment 2, cross-sectional ultrasound scans of caudal artery at the fourth coccygeal vertebra were taken on Days 0, 8, 15, 21, 29, 36, 42, and 45 to determine mean artery luminal area to evaluate vasoconstriction. In both experiments, steers were removed from pasture and housed in a dry lot and fed a corn silage diet for the duration of biopsies and ultrasound scans. Biopsied vessels used to evaluate vasoactivity were cleaned, incubated in a multimyograph, and exposed to increasing concentrations of 4-Bromo-3,6-dimethoxybenzocyclobuten-1-yl) methylamine hydrobromide (TCB2; 5HT2A agonist), guanfacine (GF; α2A-adrenergic agonist), and (R)-(+)-m-nitrobiphenyline oxalate (NBP; α2C-adrenergic agonist) in both experiments and ergovaline (ERV) and ergotamine (ERT) in Experiments 1 and 2, respectively. In Experiment 1, days off pasture × agonist concentration was not significant (p > 0.1) for all four compounds tested. In Experiment 2, GF, NBP, TCB2 and ERT were significant for days off pasture × agonist concentration interaction (p < 0.02) and vasoactivity increased over time. Vasoactivity to agonists was reduced (p < 0.05) when steers were initially removed from E+ tall fescue pasture compared to bermudagrass, but did not differ by Day 63 for any variable. Luminal areas of caudal arteries in steers grazed on E+ tall fescue relaxed and were similar to steers that had grazed bermudagrass for 36 days on non-toxic diet (p = 0.15). These data demonstrate changes in peripheral vasoactivity and recovery from vasoconstriction occur beyond five weeks off toxic pasture and 5HT2A receptors appear to be more dramatically affected in the lateral saphenous vein by grazing E+ tall fescue pasture than adrenergic receptors. [ABSTRACT FROM AUTHOR]

Red clover (Trifolium pratense L.) is an important forage legume in the United States. Improving forage quality and biomass yield is an important goal of forage breeding programs. Plant development, particularly the transition from vegetative to reproductive growth, is an important factor affecting biomass accumulation and forage quality. Thus, genetic manipulation of genes that regulate the transition from the vegetative to reproductive phase can be an efficient strategy for genetic improvement of red clover. One such gene is miR156, a microRNA gene that serves as a master regulator of vegetative phase change in land plants. We report here the development of transgenic red clover plants overexpressing the maize Corngrass1 gene encoding two tandem miR156s. The transgenic plants displayed striking phenotypic changes compared with the wild-type plants, including the increased number of shoots, delayed flowering, enhanced forage yield, and improved forage quality. These results suggest that manipulating miR156 or its target genes is a potential tool for genetic improvement of forage legumes. [ABSTRACT FROM AUTHOR]