324 research outputs found
Preweaning and Postweaning Performance of Crossbred Calves--0, 1 or 2 Ralgro Implants
The preweaning performance of 221 steer and heifer calves given differing numbers of Ralgro implants was evaluated. The steer and heifer calves given one implant had an additional 23 and 33 lb weaning weight compared to those receiving no implant. No additional response was shown by steer calves receiving a second implant 100 days after the first was given. Average daily gains during the 105-day growing period were not significantly faster than those receiving two implants during the 103-day finishing phase. This work supports other studies indicating that implanting calves at weaning time is an economical management practice. The work further indicates to feeders that calfhood implants have little or no effect on subsequent performance in the feedlot
Feeding Value of Pro-Sil Treated High-Moisture Ground Ear Corn with Two Groups of Crossbred Heifers
Pro-Sil, an ammonia-molasses-mineral suspension, has been shown to be a highly effective commercial additive for corn silage in studies at SDSU and other midwest universities. When added to corn silage at the time of ensiling, this product stimulates beneficial fermentation and increases the crude protein content of the silage, thereby reducing or eliminating the need for protein supplementation at the time of feeding. While Pro-Sil has been thoroughly tested with whole plant corn silage, no research has been conducted with ensiled high-moisture ear corn (HMEC). Since the crude protein content of HMEC is low compared to the needs of feedlot cattle, research is needed to evaluate economical methods of boosting the level of this critical nutrient. Thus, the major objective of this initial study was to compare the feedlot performance of cattle fed Pro-Sil treated HMEC or regular HMEC mixed with either a control or a urea-based protein supplement at the time of feeding. Both types of HMEC were ensiled in a plastic Silopress bag to examine the effectiveness of this storage method with HMEC. The relative performance of exotic and British crossbred yearling heifers was also studied in this trial
Effect of Length of Feeding Period on Performance of British and Exotic Crossbred Yearling Heifers
Seventy-two heifers were fed for 47, 61 and 75 days to determine the optimum feeding period for exotic cross and black baldy heifers. Average daily gains and feed conversions of the heifers were similar among treatments. Carcass weight, quality grade and yield grade increased with time on feed. Fat thickness, quality grade and yield grade increased faster for the black baldy heifers. Cost per pound of gain was similar for all treatments. The optimum weight at which to slaughter the black baldy yearling heifers appeared to be between 1000 and 1050 lb., both from a quality and economic view point. The optimum weight for slaughtering the exotic cross heifers was apparently not reached, as the last slaughter group was still gaining rapidly and efficiently with little increase in condition. The limited research conducted in this study indicates that a producer with mixed lots of cattle needs to be aware of the weight at which different types of cattle reach optimum condition. The feeder has greater flexibility in marketing the larger framed exotic cross type cattle as compared to the relatively smaller framed English breeds
Feedlot Performance of Growing Steer Calves on a High Roughage Ration Supplemented with a High Bypass or an All Natural Protein Supplement
This study was undertaken to compare a urea-based protein supplement containing meat and bone meal and dehydrated alfalfa as the primary by-pass protein source to a protein supplement containing soybean meal and sunflower meal as the protein sources
Effect of Length of Feeding Period of Performance of British and Exotic Crossbred Yearling Heifers
Producers very often question the additional length of time they should feed exotic-cross cattle as opposed to the feeding period required for the traditional British breeds of cattle. Also implied in this question in this question is the additional amount of feed needed for the exotic-cross animal to attain an optimum weight and an acceptable grade. This trial was conducted in an attempt to help answer these basic questions
Correlation entropy of synaptic input-output dynamics
The responses of synapses in the neocortex show highly stochastic and
nonlinear behavior. The microscopic dynamics underlying this behavior, and its
computational consequences during natural patterns of synaptic input, are not
explained by conventional macroscopic models of deterministic ensemble mean
dynamics. Here, we introduce the correlation entropy of the synaptic
input-output map as a measure of synaptic reliability which explicitly includes
the microscopic dynamics. Applying this to experimental data, we find that
cortical synapses show a low-dimensional chaos driven by the natural input
pattern.Comment: 7 pages, 6 Figures (7 figure files
Durable Advanced Flexible Reusable Surface Insulation
An improved flexible blanket includes a nickel-based alloy foil layer brazed to a nickel-based alloy fabric layer. The fabric layer is stitched to an underlying ceramic insulation layer
Fidelity for Multimode Thermal Squeezed States
In the theory of quantum transmission of information the concept of fidelity
plays a fundamental role. An important class of channels, which can be
experimentally realized in quantum optics, is that of Gaussian quantum
channels. In this work we present a general formula for fidelity in the case of
two arbitrary Gaussian states. From this formula one can get a previous result
(H. Scutaru, J. Phys. A: Mat. Gen {\bf 31}, 3659 (1998)), for the case of a
single mode; or, one can apply it to obtain a closed compact expression for
multimode thermal states.Comment: 5 pages, RevTex, submitted to Phys. Rev.
Quantifying impacts of short-term plasticity on neuronal information transfer
Short-term changes in efficacy have been postulated to enhance the ability of
synapses to transmit information between neurons, and within neuronal networks.
Even at the level of connections between single neurons, direct confirmation of
this simple conjecture has proven elusive. By combining paired-cell recordings,
realistic synaptic modelling and information theory, we provide evidence that
short-term plasticity can not only improve, but also reduce information
transfer between neurons. We focus on a concrete example in rat neocortex, but
our results may generalise to other systems. When information is contained in
the timings of individual spikes, we find that facilitation, depression and
recovery affect information transmission in proportion to their impacts upon
the probability of neurotransmitter release. When information is instead
conveyed by mean spike rate only, the influences of short-term plasticity
critically depend on the range of spike frequencies that the target network can
distinguish (its effective dynamic range). Our results suggest that to
efficiently transmit information, the brain must match synaptic type, coding
strategy and network connectivity during development and behaviour.Comment: Accepted for publication in Phys Rev E. 42 pages in referee format, 9
figure
Experimental determination of heat capacities and their correlation with quantum predictions
This article demonstrates an undergraduate experiment for the determination
of specific heat capacities of various solids based on a calorimetric approach,
where the solid vaporizes a measurable mass of liquid nitrogen. We demonstrate
our technique for the metals copper and aluminum, the semi-metal graphite and
also present the data in relation with Einstein's model of independent harmonic
oscillators and the more accurate Debye model based on vibrational modes of a
continuous crystal. Furthermore, we elucidate an interesting material property,
the Verwey transition in magnetite occurring around 120-140 K. We also
demonstrate that the use of computer based data acquisition and subsequent
statistical averaging helps reduce measurement uncertainties.Comment: 16 pages, 8 figures. Partially accepted in American Journal of
Physics (2011
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