New concepts in breeding barn design

Many existing swine breeding facilities have been designed to control the environment, provide continuous boar-sow contact for stimulating recently weaned sows to cycle, reduce the distance a weaned sow or boar has to be moved for mating, and reduce construction costs by not constructing breeding pens to be used only for mating. Pork producers operating these types of facilities have had problems with efficiency and accuracy of estrous detection, low percentage (70%) of sows bred twice, slick breeding floors, and excessive labor requirements. A breeding facility should be arranged so the work routines, such as estrous detection; moving, mating, and feeding animals; and recording breeding information arc easily, quickly, and safely performed. Remember, tasks that are difficult to do may never be done.; Swine Day, Manhattan, KS, November 16, 198

Effect of Type of Birth, Breed of Sire and Postweaning Nutrition on Growth of Ewe Lambs. I. Growth Parameters

A research project was initiated in the fall of 1970 to evaluate the effect of breed of sire, level of postweaning nutrition, age at first breeding and type of birth on subsequent reproductive performance of the ewe. Data from the growth phase of lambs produced in this study from 1971 through 1975 are presented in this report

Effect of Breed of Sire, Level of Postweaning Nutrition and Type of Birth on Ewe Growth and Lambing Performance at 12, 24 and 36 Months of Age

A research project was designed and initiated in the fall of 1970 to evaluate the effect of breed of sire, level of pre- and postweaning nutrition, age at first breeding and type of birth on subsequent reproductive performance of the eww. The growth of the ewe, wool production and lambing performance data of the ewes at 12, 24, and 36 months of age will be reported in this paper

Effect of Type of Birth, Breed of Sire and Postweaning Nutrition on Ewe Lambs. II. Production at 12 Months Age

The practice of breeding ewes to lamb at 12 months of age has not been widely accepted by commercial operators, even though previous research has indicated that it can be done successfully in some management systems. One reason for this might be that long-term effects on lifetime productivity have not been evaluated. This paper summarizes production performance during the first year of a lifetime study currently in progress. Data from 382 Suffolk Targhee and Targhee ewes born in 1971-1975 and developed under two different nutritional levels are included in this report. Subsequent lifetime production for these ewes will be reported when available

Induction of Parturition in Beef Cattle With Dexamethasone

In recent years many reports have shown that synthetic glucocorticoids such as dexamethasone (DXMS) and flumethasone will induce parturition in cattle when injected intramuscularly during various stages of gestation. A study was conducted at South Dakota State University to determine, under field conditions, the effectiveness of DXMS coupled with estradiol on the precision of parturition induction, the incidence of retained placentas and subsequent reproductive performance of beef cows

Picosecond ionization dynamics in femtosecond filaments at high pressures

We investigate the plasma dynamics inside a femtosecond-pulse-induced filament generated in an argon gas for a wide range of pressures up to 60 bar. At higher pressures, we observe ionization immediately following a pulse, with up to a threefold increase in the electron density within 30 ps after the filamentary propagation of a femtosecond pulse. Our study suggests that this picosecond evolution can be attributed to collisional ionization including Penning and associative ionizations and electron-impact ionization of excited atoms generated during the pulse. The dominance of excited atoms over ionized atoms at the end of the pulse also indicates an intrapulse inhibition of avalanche ionization. This delayed ionization dynamics provides evidence for diagnosing atomic and molecular excitation and ionization in intense laser interaction with high-pressure gases

Hantavirus infection in children in Argentina.

Clinical hantavirus infection was diagnosed in five Argentine children ages 5 to 11 years by immunoglobulin M (IgM)- capture enzyme-linked immunosorbent assay using Sin Nombre virus (SNV) antigens. Death in three of the children was associated with absence of detectable IgG to SNV antigens. An additional two cases in healthy children were studied: one, a breast-fed 15-month-old whose mother died of suspected hantavirus pulmonary syndrome (HPS) 8 months previously, had hantavirus IgG (> 1:6400); a second, whose mother survived HPS during month three of pregnancy, apparently had maternal antibodies no longer detectable 1 year after birth

Beable trajectories for revealing quantum control mechanisms

The dynamics induced while controlling quantum systems by optimally shaped laser pulses have often been difficult to understand in detail. A method is presented for quantifying the importance of specific sequences of quantum transitions involved in the control process. The method is based on a ``beable'' formulation of quantum mechanics due to John Bell that rigorously maps the quantum evolution onto an ensemble of stochastic trajectories over a classical state space. Detailed mechanism identification is illustrated with a model 7-level system. A general procedure is presented to extract mechanism information directly from closed-loop control experiments. Application to simulated experimental data for the model system proves robust with up to 25% noise.Comment: Latex, 20 pages, 13 figure

Dynamics and hysteresis in square lattice artificial spin-ice

Dynamical effects under geometrical frustration are considered in a model for artificial spin ice on a square lattice in two dimensions. Each island of the spin ice has a three-component Heisenberg-like dipole moment subject to shape anisotropies that influence its direction. The model has real dynamics, including rotation of the magnetic degrees of freedom, going beyond the Ising-type models of spin ice. The dynamics is studied using a Langevin equation solved via a second order Heun algorithm. Thermodynamic properties such as the specific heat are presented for different couplings. A peak in specific heat is related to a type of melting-like phase transition present in the model. Hysteresis in an applied magnetic field is calculated for model parameters where the system is able to reach thermodynamic equilibrium.Comment: Revised versio