Angus steers (n = 96; 321 ± 29 kg BW) were used to determine how previous exposure to increased dietary S would affect ruminal hydrogen sulfide concentrations ([H(2)S]) in the feedlot, to investigate the effects of dietary S on ruminal [H(2)S] during transition and finishing, and to determine if dietary S affects the glutathione status of finishing cattle. Steers were strip-grazed on smooth bro...

M any natural landscapes have undergone dramatic permanent alterations as a result of human activities, including conversion to cultural landscapes; such changes are readily observed and understood. However, extensive ecological change can also occur in regional landscapes that are maintained in a seminatural state, changes that go largely unrecognized because the regional landscape retains an ...

Throughout the western United States, the invasive annual grass, medusahead (Taeniatherum caputmedusae L. Nevski), is rapidly invading grasslands once dominated by native perennial grasses, such as bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) A). It is also invading grasslands dominated by less undesirable invasive annual grasses, especially cheatgrass (Bromus tectorum L.). Understandi...

historical records of cheatgrass Bromus tectorum invasion in North American sagebrush-steppe Sumanta Bagchi*, David D. Briske, Brandon T. Bestelmeyer and X. Ben Wu Department of Ecosystem Science and Management, Texas A&M University, 2138 TAMU, College Station, TX 77843, USA; USDA-ARS, Jornada Experimental Range and Jornada Basin LTER, New Mexico State University, MSC 3JER, Box 30003, Las Cruce...

Intake of animals grazing grass pasture is in part infl uenced by canopy density. Our objective was to determine the vertical distribution of dry matter and neutral detergent fi ber (NDF) within temperate perennial grass swards. The study was conducted in 2004 and 2005 on a Plano silt loam (fi ne-silty, mixed, superactive, mesic Typic Argiudolls). When leaf height of each grass reached 25 cm in...

Reproductive performance was evaluated in beef heifers born over a 2-yr period to determine the effects of target breeding weight (TBW) and development system (SYS) on growth and subsequent reproductive efficiency. Spring-born Angus heifers (253 ± 0.7 kg) were randomly allocated over 2 consecutive yr (yr 1, n = 80; yr 2, n = 96) to be developed to either 55% (350 kg) of mature BW (moderate gain...