Browsing by Author "McCann, Mark A."

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    Assessing the reliability of plant-wax markers to delineate diet choice and feed efficiency in beef heifers
    Vargas Jurado, Napoleon (Virginia Tech, 2012-07-24)
    Estimating feed efficiency in grazing environments is challenging due to difficulties in quantifying food intakes and diet choices in free-grazing animals. The plant-wax marker technique may be a useful tool to redress this problem. However, its reliability needs to be validated before its wider application. This study was designed to assess the reliability of plant-wax markers for estimating botanical composition of test diets, and diet choices in beef cattle, and provided opportunities to evaluate efficiency in growing heifers. To test estimation of botanical composition, samples of red clover and fescue hay were mixed to form test diets containing 0-100% of either forage. To test estimation of diet choices, 24 heifers from large and moderate frame size lines were evaluated at two instances. Cubed red clover and fescue hays were offered ad libitum. After an acclimation period, feed intakes and body weights were collected for 10 days; fecal samples were collected for the final 5 days. Hydrocarbons and alcohols were quantified with gas chromatography. Estimates were based on least squares. Operator expertise affected measured concentrations of shorter-chained n-alkanes (P<0.041) and long-chain alcohols (P<0.02). Still, overall reliability of the technique was unaffected. Large and moderate framed animals did not differ in efficiency (P>0.05), although large framed animals had increased red clover intakes (P<0.01). Once corrected for fecal losses of n-alkanes, diet choices were estimated accurately. Plant-wax markers provided reliable estimates of botanical composition of diets, and diet choices of animals, suggesting it is a valuable tool to assess efficiencies of grazing cattle.
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    Economic Pasture-Based Cow-Calf Systems for Appalachia
    Emenheiser, Joseph Carl (Virginia Tech, 2014-01-06)
    Pasture-based beef production is well-suited for the Appalachian region of the United States. This research investigated pasture, beef cattle, and economics components within the cow-calf sector of pasture beef production, and presents implications of their interplay for the vitality of the whole system. Samples of forage DM mass and CP, ADF, NDF, and ash contents in each paddock of a rotational stocking system were collected monthly for 4 grazing seasons. Effects of month, stockpiling, hay feeding, temperature, precipitation, and durations of paddock grazing and rest on forage mass and quality measurements were investigated. The system was complex and dynamic; precipitation and rest days in particular showed clear interactions with both month and stockpiling when predicting forage mass and quality. Available DM, TDN, and CP were compared to nutrient density requirements for beef cows to conclude that the system met or exceeded requirements. Six years of production data from a spring-calving cow-calf enterprise that utilized rotational stocking and fall stockpiling were analyzed. Comparisons among 2 cow frame size and 2 calf creep system treatments for production efficiency (total weaning weight per land area), and net returns to the enterprise, were made. Pastures with medium frame cows and designated creep systems had the greatest production efficiency, but also had the highest costs and netted the least returns. Greatest net returns were achieved in large frame, forward creep systems, which had the lowest production efficiency but also the lowest costs. Provided the quality of calves produced is suitable for other phases of the production stream, we conclude that minimizing costs rather than maximizing productive outputs is a better focus for cow-calf enterprises faced with similar decisions among frame size and creep system treatments.
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    Effect Of A Cidr Insert And Flunixin Meglumine Administered At The Time Of Embryo Transfer On Pregnancy Rate And Resynchronization Of Estrus In Beef Cattle
    Purcell, Scott Hudson (Virginia Tech, 2004-06-23)
    The objectives of this study were to evaluate the effects of flunixin meglumine (FM), an inhibitor of PGF2a synthesis, administered at the time of embryo transfer (ET) and insertion of an intravaginal progesterone-releasing device (CIDR) at the time of ET on pregnancy rates (PR) and the resynchronization of estrus. Beef cows (n = 796) and heifers (n = 108) at three locations were assigned randomly within age to one of four groups in a 2 x 2 factorial arrangement of treatments with injection of FM (500 mg i.m.; Phoenix Scientific, St. Joseph, MO) 2 to 12 min prior to ET and insertion of a CIDR (1.38 g progesterone; Pfizer, New York, NY) for 13 d immediately following ET as main effects. Fresh or frozen embryos (Stage = 4 or 5; Grade = 1 or 2) were randomly assigned to be transferred to recipients on d 6 to 9 of the estrous cycle. At Location 2 a subset of fresh embryos were split and transferred as fresh half embryos (n = 192). Recipients at Location 2 only (n = 493) were observed for signs of return to estrus beginning 9 d after ET. Recipients that returned to estrus at Location 2 were either bred by AI 12 h after estrus or received an embryo 7 d after estrus. Pregnancy was diagnosed by ultrasonography. Pregnancy rates were analyzed using the LOGISTIC procedure of SAS. Pregnancy rates of split embryo recipients were analyzed separately using the same statistical procedure. Variation in the timing of the return to estrus was determined by an F-test for heterogeneity of variances. Following the initial ET, pregnancy rates of recipients receiving whole embryos were not affected by CIDR administration (P > 0.05; 65% with CIDR, 70% without CIDR), however, there was a significant FM x location interaction on PR (Location 1, 89 vs. 57%; Location 2, 69 vs. 64%; Location 3, 64 vs. 67% for FM vs. no FM, respectively). There was a significant CIDR x FM interaction on PR of recipients receiving split embryos. Pregnancy rates of split embryo recipients receiving CIDR treatment (54%) or FM treatment alone (41%) were less than controls (64%). However, recipients receiving both CIDR and FM had PR similar to controls (60%). The timing of the return to estrus was more synchronous (P < 0.01) for recipients fitted with a CIDR, but PR of recipients bred following a return to estrus did not differ in cows receiving or not receiving a CIDR (P > 0.13; 68 and 62%, respectively). Effects of FM on PR were location dependent and CIDR insertion at ET improved synchrony of the return to estrus.
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    Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose
    Wettathperuma Arachchige, Deepthi Nayananjalie (Virginia Tech, 2012-12-12)
    The aims of the first study were to determine the effects of early weaning followed by a period of high-grain feeding on signaling protein phosphorylation in muscle and on acetate clearance in growing steers.  Twelve Angus X Simmental steers were used in the study.  Six steers were weaned early (EW) and fed a high-gain diet for 148 d and the remainder were weaned at the normal age (NW).  Longissimus muscle tissue biopsies were collected to determine total and phosphorylated forms of AMP kinase and downstream proteins of the mTOR signaling pathway.   Of the 12, 8 steers were used to assess acetate clearance at different age points.  During early grain feeding, phosphorylated:total ratios of rpS6 and S6K1 were greater in EW steers and they had lower acetate clearance rates and greater synthesis rates.   The objectives of second study were to assess the effects of early grain feeding on acetate and glucose turnover rates, palmitate synthesis, and on acetate and glucose preference by subcutaneous, intramuscular and visceral adipose tissues in finishing steers.  Sixteen Angus x Simmental steers were infused continuously with [2H3] acetate (n = 8) or [U-13C6] glucose (n = 8), over a 12 h period immediately prior to harvest.  Plasma acetate and glucose enrichment, and palmitate enrichment in different adipose tissue locations were determined.  There were no treatment effects on acetate or glucose turnover rates or palmitate fractional synthesis rates (FSR).  Acetate turnover and palmitate FSR from acetate were greater than the corresponding rates from glucose.  There were no differences in preference for acetate or glucose among the fat depots. In conclusion, phosphorylation ratios of signaling proteins were not affected treatment.  Acetate clearance increased when steers were heavier and older.  Thus older calves are able to clear more acetate per unit of time and body mass than younger calves reflective of an enhanced ability to utilize the substrate.  There were no differences in preference for acetate and glucose among the major fat depots.  Thus diets leading to high glucose supply will not preferentially direct energy storage to intramuscular stores.
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    The Effect of Three Fescue Types and Lakota Prairie Grass on Copper Status, Dry Matter Intake, and Alkaloid Appearance of Beef Steers
    Stewart, Robert Lawton Jr. (Virginia Tech, 2006-10-27)
    Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] is an important forage crop in the United States and covers over 14 million ha. The presence of Neotyphodium coenophialum, an endophytic fungus in tall fescue, is associated with several disorders in grazing livestock, but also increased persistence of tall fescue. These disorders, commonly called fescue toxicosis, are responsible for large economic losses in the beef cattle industry each year. This research examined the effect of three fescue types [endophyte-infected Kentucky 31 tall fescue (E+), endophyte-free Kentucky 31 tall fescue (E-), non-ergot alkaloid-producing endophyte Q4508-AR542 tall fescue (Q)], and Lakota prairie grass (L; Bromus catharticus Vahl.) on animal response, alkaloid appearance, DMI, and copper status. Ergovaline (EV) is the most abundant ergot alkaloid in tall fescue and has previously been considered the causative toxin in fescue toxicosis. More recently it is simpler ergot alkaloids, such as lysergic acid amide (LSA) have been implicated. The objective of the first project was to evaluate animal performance and alkaloid (EV and LSA) appearance in forage and ruminal fluid of steers grazing E-, Q, E+, and L. Average daily gains were greater (P < 0.05) on E-, Q and L compared to E+, and there was a trend (P = 0.11) for gains on E- to be higher than with Q. The seasonal appearance of LSA in ruminal fluid was similar to the seasonal pattern of alkaloids in E+ forage. Ergovaline was not detectable in ruminal fluid of steers grazing E+. Alkaloids were not detectable in forage or ruminal fluid of steers grazing E-, Q, or L. The appearance of LSA in ruminal fluid of steers grazing E+ suggests that this alkaloid may contribute to fescue toxicosis. Low DMI of animals grazing E+ tall fescue is considered a key factor in decreased animal performance compared to other fescue types. The objective of the second project was to evaluate DMI of steers grazing E-, E+, Q, and L pastures using the alkane technique. Dry matter intake of steers grazing E- was greater (P < 0.001) than Q, E+, and L and DMI of steers grazing Q and E+ were similar (P > 0.10) in 2004. In 2005, DMI did not differ (P = 0.23) among fescue types. These results suggest that decreased DMI effects ADG of steers grazing E+ compared to those grazing E-, and lower DMI of Q suggests that the fescue variety Q4508 may not be the optimal variety for the incorporation on non-ergot alkaloid-producing endophytes. Reactive oxygen metabolites such as superoxide (O₂⁻) are produced by both endogenous and exogenous sources and an accumulation of these compounds can result in oxidative stress. Copper/zinc superoxide dismutase (SOD) is a Cu-based antioxidant metalloprotein that acts as a defense against oxidative stress by the scavenging of O₂⁻. Neotyphodium-infected tall fescue is typically lower in Cu which could potentially increase oxidative stress of animals grazing this forage. Therefore the objective of the third project was to investigate the Cu and SOD status of steers grazing E-, E+, Q, and L forages. Copper levels of all forages were below the dietary requirement (10μg Cu/g DM) of growing cattle. In 2004, steers grazing E+ exhibited lower (P <0.05) liver Cu compared to E- and Cu intake was lower (P < 0.001). Cu/Zn SOD enzymatic activity and mRNA relative expression did not differ (P > 0.10) among treatments. Copper intake of steers grazing E+ tall fescue was sufficient to maintain, but not replenish liver Cu, and SOD status did not appear compromised by grazing E+ at these Cu levels.
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    Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers
    Smith, Jason Kaleb (Virginia Tech, 2015-09-03)
    Beef cattle producers continuously search for nutritional management options that provide flexibility to production scenarios. Due to its positive effects on maternal productivity, early weaning is one such alternative strategy that has received considerable interest. To better understand the effects of early weaning on calf productivity, an extensive literature review and three experiments were conducted to evaluate the effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. In experiment I, which included 90 Angus-sired steers from four calving seasons, early weaning followed by a short ad libitum concentrate-feeding and pasture-backgrounding phase reduced finishing residual feed intake (RFI) by 7 % (P < 0.0001) and increased carcass marbling score (MS) by 10 % (P < 0.01) when compared to conventionally weaned (CW) contemporaries. Similar effects were observed in experiment II, which included 28 Angus and Simmental-sired steers, as early weaning reduced RFI (P < 0.01) and increased carcass MS (P < 0.01). Lung mass of early weaned (EW) steers was greater than their CW contemporaries (P < 0.05), and was inversely related to RFI (R2 = 0.17; P < 0.05). Finishing treatments in this experiment included a high corn ration and an alternative low corn ration that iso-calorically replaced 50 % of the DM from corn with dried corn gluten feed. Iso-caloric replacement of corn reduced lung mass (P < 0.01), and when combined with the observed increase of EW steers suggests that lung development is affected by dietary energy type at various stages of growth. In experiment III, objective analyses of ribeye steaks obtained from steers included in experiment two revealed that early weaning increased cross-sectional muscle fiber area by 28 % (P < 0.001) and tended to increase (P = 0.08) Warner-Bratzler shear force by 36 %. Nonetheless, these effects were not great enough to alter un-trained consumer perception of texture (P ≥ 0.65), juiciness (P ≥ 0.55), flavor (P ≥ 0.25) or overall acceptability (P ≥ 0.34). Collectively, these results indicate that early weaning enhances finishing feed efficiency and carcass marbling without affecting un-trained consumer sensory perception.
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    Effects of Phosphorus Supplementation on Grazing Beef Cattle
    Neil, Scott Joseph (Virginia Tech, 2015-11-04)
    Phosphorus (P) losses due to overfeeding of the mineral to livestock can contribute to surface water degradation. The objective of this study was to examine the impact to supplementing various levels of mineral P to grazing beef cattle. A producer survey and a research trial were conducted to examine the effects of supplementing mineral phosphorus (P) to grazing cattle. In the first study, mineral tags, producer surveys, and fecal, forage, and soil samples were collected from beef cattle operations in Virginia's Chesapeake Bay watershed. Samples (n=166) were collected from 120 producers in 11 counties. Soil test P results were based on Virginia Cooperative Extension soil test guidelines characterized as low (12 %), medium (37 %), high (35 %), and very high (16 %). Pasture grab samples contained 0.34 ± 0.12% P and forage P concentration increased (P < 0.01) across soil P categories going from low to very high. Fecal total phosphorus (TP) was lowly correlated (R2 = 0.18, P < 0.01) to forage P concentration. Mineral supplements were categorized as nil (<1.0% P), low (1.0-<3.0% P), medium (3.0-<6.0% P), and high (>6.0% P). Fecal TP and inorganic phosphorus (Pi) concentration increased (P < 0.01) with mineral P levels. Fecal TP and Pi were lower (P < 0.01) when nil and low P mineral were supplemented as compared to medium and high P mineral. Soluble P (defined as fecal Pi/fecal TP*100) also increased (P < 0.01) with increasing mineral P content going from nil to high. All farms surveyed required little or no P supplementation in regard to beef cattle P requirements. The majority (82%) of producers were receptive to modifying mineral P supplementation practices based on forage P levels. A 56-d study was also conducted with eight yearling Hereford steers (261±30 kg) grazing cool-season grass fall re-growth to determine the effects of varying levels of P supplementation on fecal P excretion. Treatments consisted of dicalcium phosphate supplemented at 0 (D1), 10.0 (D2), 20.0 (D3), or 30.0 (D4) g/d in a randomized 4x4 replicated Latin square design. These treatments provided an additional 0, 1.9, 3.7, and 5.6 g/d of P respectively. Two esophageally cannulated steers were used to collect forage samples for nutrient analysis. Forage P content was analyzed from hand collected samples. Forage P concentrations averaged 0.49% of dry matter (DM) across all periods. Chromic oxide (Cr2O3) was administered twice daily via gelatin capsule at 0630 and 1830 to serve as an external marker for determination of fecal dry matter excretion (DME). Indigestible NDF (iNDF) was used as an internal marker to determine dry matter intake (DMI). Due to the high forage P content, average P intake was in excess of National Research Council (NRC) requirements for all diets (D1 = 281%; D2 = 297%; D3 = 323%; D4 =348%). Orthogonal contrasts were performed to assess the relationship between treatment and P excretion. A linear response (P < 0.01) in daily inorganic P (Pi) excretion (0.054, 0.052, 0.062 and 0.063 g/kg of BW ± 0.003 for D1, D2, D3 and D4, respectively) was observed across treatments. Daily total P (TP) excretion increased linearly (P < 0.01) across treatments (0.080, 0.079, 0.092 and 0.093 g/kg of BW ± 0.003 for D1, D2, D3 and D4, respectively. When forage P content is sufficient to meet the requirement of grazing cattle, increasing P supplementation results in greater P excretion without additional benefits to growth or nutrient digestibility.
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    Estimating forage mass of tall fescue pastures and dry matter intake and digestibility of fescue forage by beef steers
    Lopez-Guerrero, Isaias (Virginia Tech, 2005-01-13)
    A series of three experiments were conducted to evaluate different methods of estimating forage mass of tall fescue pastures, and dry matter intake and digestibility in beef steers under indoor and grazing conditions. Forage mass was estimated with the herbage cutting method (HCM) and three indirect methods; the pasture capacitance meter (PCM), the plate meter (PPM), and the visual estimation (VE). The coefficients of determination from the calibration equations were 0.686, 0.751, and 0.862 for the PCM, PPM, and VE, respectively. There were differences in forage mass estimates due to sampling method, sampling date, and their interaction. The second experiment was a digestion trial conducted with confined animals to determine the recovery rate of chromic oxide and alkanes from controlled release capsules and to evaluate the accuracy of the concurrent estimations of intake and digestibility. No difference was found in the recovery rate of either alkanes or chromic oxide during the 7 d of the collection period. Likewise, actual fecal output, dry matter intake, and digestibility were not different from the estimated values. However, estimated values had to be adjusted for the respective recovery rate. The third experiment was conducted under grazing conditions to evaluate the chromic oxide controlled release capsule technique in estimating intake and digestibilty. In this trial, although the recovery rate of the marker was extremely high (avg. = 1.89), the actual and estimated values of dry matter fecal output, intake, and digestibility were not different. Again the recovery rate had to be used as a correction factor.
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    Fecal Phosphorus Characteristics of Forage-Fed Beef Cattle
    Riley, Elizabeth (Virginia Tech, 2013-06-14)
    Phosphorus loads in waterways are a focus of environmental concern. Animal agriculture\'s contribution to this problem has been documented and efforts are focused on mitigating the issue. The effect of increasing amounts of mineral P supplementation on fecal P characteristics was studied in forage fed beef steers. Eight Hereford steers were fitted with total fecal collection bags and fed four diets with a low P grass hay and supplemented with increasing amounts of a mineral source of P, dicalcium phosphate. Dietary DM P concentrations were 0.10 (no P supplementation), 0.23, 0.34, and 0.45% P. Manure was sampled and dried, followed by analysis for total P and inorganic P (Pi). Blood was collected via jugular venipuncture following each collection period and plasma Pi was quantified. Total fecal P increased linearly with increasing dietary P concentration: 6.44, 10.6, 16.1, and 18.8 g/d (P < 0.0001). Fecal Pi increased linearly with increasing dietary P concentration: 1.58, 2.43, 2.74, and 3.84 g/d (P = 0.0119) Manure P solubility, however, did not increase with increasing dietary P concentration: 23.6, 22.3, 17.3, and 20.2% (P = 0.3646). Plasma Pi increased linearly with increasing dietary P (P = 0.0047). ADG and G:F were not affected by increasing dietary P content. Reducing or eliminating mineral P supplementation to forage fed beef animals is possible, if forage base proves to be adequate in P. Reducing dietary P reduces fecal P excretion and the pollution potential in ecologically sensitive areas like the Chesapeake Bay watershed.
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    Forage Utilization and Nitrogen Management of Tall Fescue Stockpiled for Winter Grazing
    Shireman, Nathan Todd (Virginia Tech, 2015-06-30)
    The Southeastern United States offers a beneficial environment for stocker and cow-calf production. Abundant tall fescue grass offers a feed source that has been underutilized. These studies evaluated how nitrogen rate and source can affect yield and nutritional quality of fall stockpiled tall fescue, and how grazing methods impact weight gains, forage utilization, and forage nutritive value. The first study evaluated the impact of N rate and source on the yield tall fescue stockpiled for winter grazing. In mid-September, seven N sources (ammonium sulfate (AS), ammonium nitrate (AN), urea + Agrotain @ 2.1 l/Mg (AG2), urea + Agrotain @ 4.2 l/Mg (AG4), urea + Agrotain @ 6.3 l/Mg (AG6), Nutrisphere (NuS), and urea) were applied at 0, 45, 90, and 135 kg N/ha. Ammonium sulfate produced the highest nutritive values of all N sources. Only yield in 2012 was found to be influenced by N volatilization inhibitors; said products had no effect on nutritive value. The second study evaluated how grazing methods impact nutritive value, ADG, and utilization of tall fescue stockpiled for winter grazing. Three treatments (continuous grazing, moved once per week, and moved twice per week) were used. In year one, cattle moved once and twice per week showed significantly higher ADG (P < 0.05) than the continuous treatment. In year two, cattle that continuously grazed had higher ADG (P <0.05), than cattle moved once and twice per week. Cattle moved once and twice per week showed greater forage utilization (P < 0.05) than cattle that continuously grazed.
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    Livestock Update. April 2010
    Greiner, Scott P.; McCann, Mark A.; Currin, John F.; Whittier, W. Dee (Virginia Cooperative Extension, 2010-03-29)
    Includes articles on April beef management, cow herd performance and profitability, fall calf options, polio associated with feeding corn gluten, effect of winter on cow pregnancy rates, and foot care and treatment in sheep.
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    Livestock Update. April 2014
    Greiner, Scott P.; McCann, Mark A.; Saville, Joi (Virginia Cooperative Extension, 2014-04-18)
    Includes articles on beef herd management, several award recipients, the 2014 southwest bull test, management for fall lambing success, and a sheep update.
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    Livestock Update. August 2010
    Greiner, Scott P.; McCann, Mark A.; Kuehn, Larry Alexander; Thallman, Mark (Virginia Cooperative Extension, 2010-08-01)
    Includes articles on August beef management, summer pasture shortage, 2010 across-breed EPD table, upcoming stocker conference, upcoming Virginia Simmetal field day, sheep update, lamb management, and coping with drought for the sheep flock.
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    Livestock Update. August 2012
    Greiner, Scott P.; McCann, Mark A.; Porr, C. A. Shea (Virginia Cooperative Extension, 2012-08-16)
    Includes articles on August beef management, evaluating nutritional needs for winter, Goat Day 2012, large animal emergency response training, Sheep Field Day, sheep sales, and sheep breeding tips.
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    Livestock Update. August 2013
    Greiner, Scott P.; McCann, Mark A.; Neil, Scott J.; Harmon, Deidre D.; Whittier, W. Dee (Virginia Cooperative Extension, 2013-08-09)
    Includes articles on August herd management, phosphorus supplementation of beef cattle, 2013 across-breed EPD table, Applied Reproduction in Beef Cattle event, sheep breeding season tips, and a sheep update.
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    Livestock Update. August 2014
    Greiner, Scott P.; McCann, Mark A.; Saville, Joi; Neil, Scott J.; Harmon, Deidre D.; Callan, Peter L.; Estienne, Mark J.; Wiegert, Jeffrey; Clark-Deener, Sherrie (Virginia Cooperative Extension, 2014-09-15)
    This LIVESTOCK UPDATE contains timely subject matter on beef cattle, horses, poultry, sheep, swine, and related junior work. This issue includes: Dates to Remember; August Herd Management Advisor; Weaning Nutrition and Management; Breeding Season Management - Ewes and Rams; 2014 Small Ruminant Field Day; Heat Stress and Small-Scale and Niche Market Pork Production in Virginia,
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    Livestock Update. December 2009
    Greiner, Scott P.; McCann, Mark A.; Currin, John F.; Eversole, Dan Edward (Virginia Cooperative Extension, 2009-12-03)
    Includes articles on December beef management, crossbreeding cattle, upcoming beef webinar, winter feeding of beef herds, and 2009 Hokie Harvest sale results
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    Livestock Update. December 2011
    Greiner, Scott P.; McCann, Mark A.; Whittier, W. Dee (Virginia Cooperative Extension, 2011-12-12)
    Contains articles on December beef management, an upcoming beef webinar, Johne's disease, a shepherds' symposium and a sheep update
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    Livestock Update. December 2012
    Greiner, Scott P.; McCann, Mark A. (Virginia Cooperative Extension, 2012-12-20)
    Includes the December and January beef management calendars, announcement of an upcoming webinar and symposium, 2012 Culpeper bull sale results, summary of the national beef quality audit, and winter sheep management tips.
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    Livestock Update. February 2010
    Greiner, Scott P.; McCann, Mark A.; Wahlberg, Mark L.; Estienne, Mark J.; Harper, Allen F. (Virginia Cooperative Extension, 2010-02-02)
    Includes articles on February beef management, upcoming beef convention and webinar, including clover in forage plans, crossbreeding cattle, buying bulls, bull test and bred heifer sale, ewe nutrition and management, newborn lamb management, and swine welfare