Using a mixture of cottonseed hulls and cottonseed meal to replace alfalfa hay in diets for stressed feeder calves

One 28-day receiving experiment was conducted using 625 exotic × British cross heifers to evaluate growth performance and morbidity on receiving diets that contained either alfalfa hay or a pellet composed of 65% cottonseed hulls and 35% cottonseed meal as the roughage source. Heifers fed the cotton byproduct pellet consumed more feed (P<0.01) but tended to be less efficient than those fed alfalfa hay. Daily gain was comparable between diets (P>0.05), and the percentages of heifers diagnosed, treated, or retreated for respiratory disease were similar

Evaluation of Ralgro® on pasture and subsequent feedlot performance and carcass merit of mexican crossbred steers

A pasture/feedlot field study was conducted to evaluate the effects of a single Ralgro® implant during the stocker phase on steer grazing performance and subsequent feedlot performance and carcass merit. A total of 2,764 steers of Mexican origin averaging 449 lb were assembled in Texas and shipped to Kansas, where they grazed on three intensively-early-stocked Flint Hills pastures. At initial processing, the steers were individually weighed and randomly assigned to either a non-implanted control group or a Ralgro implant group. Ralgro steers gained more (23 lb; P<0.01) than controls during the 82- to 93-day grazing phase. Following the grazing phase, all steers were shipped to a commercial feedlot in southwestern Kansas where steers from each pasture were individually weighed and given a single Component E-S® implant. Immediately after processing, steers from each pasture were sorted into either a light- or heavy-weight pen, regardless of pasture implant treatment, resulting in six feedlot pens. Days on feed ranged from 127 to 197. Control steers gained faster (P<0.01) during the feedlot phase; however, Ralgro steers had higher cumulative weight gains across the combined pasture and feedlot phases (P<0.01) and averaged three fewer days on feed (P<0.05). There were no significant differences for marbling, fat thickness, ribeye area, KPH fat, or yield grade. Ralgro steers had lower (P<0.05) quality grades because of a higher incidence (P<0.001) of steers with B and C carcass maturities

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

A ubiquitous biological material, keratin represents a group of insoluble, usually high-sulfur content and filament-forming proteins, constituting the bulk of epidermal appendages such as hair, nails, claws, turtle scutes, horns, whale baleen, beaks, and feathers. These keratinous materials are formed by cells filled with keratin and are considered 'dead tissues'. Nevertheless, they are among the toughest biological materials, serving as a wide variety of interesting functions, e.g. scales to armor body, horns to combat aggressors, hagfish slime as defense against predators, nails and claws to increase prehension, hair and fur to protect against the environment. The vivid inspiring examples can offer useful solutions to design new structural and functional materials. Keratins can be classified as α- and β-types. Both show a characteristic filament-matrix structure: 7 nm diameter intermediate filaments for α-keratin, and 3 nm diameter filaments for β-keratin. Both are embedded in an amorphous keratin matrix. The molecular unit of intermediate filaments is a coiled-coil heterodimer and that of β-keratin filament is a pleated sheet. The mechanical response of α-keratin has been extensively studied and shows linear Hookean, yield and post-yield regions, and in some cases, a high reversible elastic deformation. Thus, they can be also be considered 'biopolymers'. On the other hand, β-keratin has not been investigated as comprehensively. Keratinous materials are strain-rate sensitive, and the effect of hydration is significant. Keratinous materials exhibit a complex hierarchical structure: polypeptide chains and filament-matrix structures at the nanoscale, organization of keratinized cells into lamellar, tubular-intertubular, fiber or layered structures at the microscale, and solid, compact sheaths over porous core, sandwich or threads at the macroscale. These produce a wide range of mechanical properties: the Young's modulus ranges from 10 MPa in stratum corneum to about 2.5 GPa in feathers, and the tensile strength varies from 2 MPa in stratum corneum to 530 MPa in dry hagfish slime threads. Therefore, they are able to serve various functions including diffusion barrier, buffering external attack, energy-absorption, impact-resistance, piercing opponents, withstanding repeated stress and aerodynamic forces, and resisting buckling and penetration. A fascinating part of the new frontier of materials study is the development of bioinspired materials and designs. A comprehensive understanding of the biochemistry, structure and mechanical properties of keratins and keratinous materials is of great importance for keratin-based bioinspired materials and designs. Current bioinspired efforts including the manufacturing of quill-inspired aluminum composites, animal horn-inspired SiC composites, and feather-inspired interlayered composites are presented and novel avenues for research are discussed. The first inroads into molecular-based biomimicry are being currently made, and it is hoped that this approach will yield novel biopolymers through recombinant DNA and self-assembly. We also identify areas of research where knowledge development is still needed to elucidate structures and deformation/failure mechanisms

Research to practice : integrating reading and writing in a kindergarten curriculum

Portions of paper presented at the Conference on Reading and Writing Connections sponsored by the Center for the Study of Writing at Berkeley and the Center for the Study of Reading at the University of Illinois in Urbana-Champaign, Oct. 19-21, 1986.Includes bibliographical references (leaves 12-13)Funded by the United States Department of Education through grant no. OERI-G-86-0004 awarded to the University of Californi

Rethinking School Readiness

In the United States, for typically developing children, age has historically been the most common factor determining when a child starts formal schooling. Re-cently, there has been increased emphasis on other indicators of being ready for school. Beginning with Head Start in 1965 and mushrooming into state-funded prekindergarten programs in most U.S. states, preschool has been viewed as an intervention to facilitate school readiness for children from low-income families. In 1986 in the United States, an amendment to Public Law 94-142 extended pre-school intervention services to children with disabilities. Confusion still abounds, however, about what the concept of school readiness means and how it would translate into classroom practices and school policies that would help children be more school ready. This paper will focus on alternative definitions of school readiness, the measurement of readiness skills, and implications for new practices and policies

Predicting success on high-stakes math tests from preschool math measures among children from low-income homes.

State-mandated tests have taken center stage for assessing student learning and for holding teachers and students accountable for achieving adequate progress. What types of early knowledge predict performance on these tests, especially among low-income children who are at risk for poor performance? We report on a longitudinal study of 519 low-income American children ages 5–12, with a focus on mathematics performance. We found that nonsymbolic quantity knowledge and repeating pattern knowledge at the end of preschool were reliable predictors of performance on standards-based high-stakes tests across three different grade levels (4th–6th grade), over and above other math and academic skills. Further, these effects of preschool math knowledge were partially mediated through symbolic mapping and calculation knowledge at the end of 1st grade. These findings suggest that nonsymbolic quantity knowledge and repeating pattern knowledge prior to formal schooling are valuable indicators of low-income children’s performance on high-stakes state math tests in the middle grades

Evaluation of performance in receiving heifers fed different sources of dietary lipid

Two 35-day receiving experiments were conducted using 668 highly stressed crossbred beef heifers to evaluate differences in growth performance, morbidity, and mortality when fed diets containing differing sources of dietary lipid. Heifers received diets containing beef tallow, tallow enriched with a microalgae product containing a high proportion of docosahexaenoic acid (an omega-3 fatty acid), full-fat soybeans, or ground flaxseed. All diets contained approximately 60% concentrate and 40% roughage (alfalfa hay). Feed intake, daily gain, and feed efficiency were poorer (P<0.05) for cattle fed full-fat soybeans than for those fed the other treatments. Feed intake tended to be reduced when micro-algae was top-dressed to the diet, but gain was not negatively impacted. In Trial 2, feed efficiency was improved by the micro-algae. No notable differences among treatments were evident in the percentage of cattle treated for bovine respiratory disease, but cattle fed flaxseed tended to respond better to therapeutic treatments, requiring fewer retreatments