The Effects of Oral Antibiotic Therapy on Productivity and Immune Function Following Challenge with E. coli and Rotavirus

Early weaning programs have been aimed at the control and elimination of respiratory infections in the young pig. Segregation from their dams at less than 21 days, batch rearing with all-in and all-out by room, building, or site, and proper biosecurity (cleaning, disinfecting, and quarantine) are mandatory to implement early weaning programs1. Early weaning with all its components gives a tremendous economic advantage to those who use this technology. This technology however does not come without a cost. This requires necessary building sites, scheduling and a high level of management. Enteric infections such as neonatal coccidiosis and post weaning diarrhea problems have not been prevented by early wean programs. Although the Pork Quality Assurance Program has been developed to achieve the highly desirable goal of reduced antibiotic use, there are feed and water medication is needed for prevention and control of enteric infections. We are interested in the effects of low levels of conventional water and feed grade antibiotic treatments on performance and immunological parameters of the young pig infected with the common enteric pathogens, E. coli and rotavirus. Previously, we had tested this treatment at both a research facility and a commercial operation and had shown increased production and decreased immunological response in the treated animals23. We have established that the use of such a program would be a benefit to those producers who do not have the production facilities that would allow early weaning (7-10 days) and/or multi-site production. However the effect of these oral treatments on minimizing production losses and activation of the immune system following infection with enteric infections has not been established. The purpose of this study was to measure production and immunological parameters in orally medicated and control animals following a post weaning E. coli and rotavirus challenge

The State-of-Art of Underwater Vehicles - Theories and Applications

An autonomous underwater vehicle (AUV) is an underwater system that contains its own power and is controlled by an onboard computer. Although many names are given to these vehicles, such as remotely operated vehicles (ROVs), unmanned underwater vehicles (UUVs), submersible devices, or remote controlled submarines, to name just a few, the fundamental task for these devices is fairly well defined: The vehicle is able to follow a predefined trajectory. AUVs offer many advantages for performing difficult tasks submerged in water. The main advantage of an AUV is that is does not need a human operator. Therefore it is less expensive than a human operated vehicle and is capable of doing operations that are too dangerous for a person. They operate in conditions and perform task that humans are not able to do efficiently, or at all (Smallwood & Whitcomb, 2004; Horgan & Toal, 2006; Caccia, 2006)

Thermal Environmental Effects and Group Size on Growing Swine Immune Status

The effects of environmental conditions on the immune system of growing pigs (30-50 kg) were studied using T and B cell proliferation counts. Pigs were exposed to a constant 32°C ambient temperature versus a naturally occurring diurnal temperature variation during hot weather and a constant 10°C vs 21°C ambient temperature during cold weather. In addition, T and B cell proliferation counts were compared for pigs in single, 9 and 18 pigs/pen group sizes. Concancavalin A (ConA), Phytohemagglutinin (PHA) and Staphylococcal enterotoxin B (SEB) mitogens were used to determine T cell activation over time. Pokeweed (PWM), Lipopolysaccharide (LPS) and Salmonella typhimurium mitogen (STM) mitogens were used to determine B cell proliferation over time. ConA tests revealed significant (P\u3c0.01) increases in T cell proliferation over time for both temperature treatments during hot weather. No significant differences in B cell proliferation were noted during the hot weather trials. A general decline in T cell activation over time was noted in both temperature treatments during cold weather. Significant (P\u3c0.01) reductions in B cell activation were noted for all pigs in the cold weather trials. T and B cell proliferation comparisons for group size at all temperature treatments were non-significant. The objective of this experiment was to find what effects temperature and group size have on the capacity and function of a growing pig\u27s immune system

The Effect of Diet and Oral Antibiotic Therapy on Immune Function and Productivity in Young Pigs

Medicated early weaning programs have been shown to be an excellent method to control disease incidence in the young pig. Additional research by Dritz, et al1, showed that early weaning at 7-10 days without medication resulted in significant weight gains over conventional weaning at 14-17 days. We were interested in the effects of low levels of conventional water and feed grade antibiotic tratments on performance and immunological parameters of the young pig in a commercial operation. Previously, we had tested this treatment at a research facility and had shown increased production and a decreased polyclonal immunological response in the reated animals23. The use of such a program would be a benefit to producers who do not have the production facilities that allowing for early weaning (7-10 days) and/or multisite production. A study was conducted to determine the effect of AureomycinTM and Aureo-SulmetTM on production. The study was a 2X2 factorial experiment to determine the effect of weaning treatment and nutrition level on immune response

Efficacy of High Oil Corn in Reducing the Severity of a PRRSV Challenge in Growing Pigs

The objectives of this experiment were to determine the effects of high oil corn (HOC) on the aerosol transmission of the porcine reproductive and respiratory synrome virus (PRRSV), and the effects of HOC on PRRSV seroconversion in growing pigs. One hundred PRRSV negative gilts (25 kg) were housed in 1 of 2 mirror imaged rooms. Both rooms contained 10 pens with 5 pigs/pen, and each room had its own separate ventilation and maure handling systems. The study was arranged in a 2 x 2 factorial arrangement. The main effects consisted of a dietary energy source, (#2 yellow corn (CON) and HOC), and with or without a virus challenge (VC). A three-phase feeding prgram was used, and in each phase the CON nd HOC diets contained the same lysine:calorie ratios. Animals were allowed to acclimate ot their respective diets for two weeks before the VC was administered At day 14, fifty pigs (pigs from 5 pens in each room) were inculated with a tissue culture infectious does (TCID) 50 of PRRS virus 2367 (1 x 104) intranasally. Blood was collected twice weely from day 7 to day 64 post-inculation (PI) and analyzed for serum PRRSV concentrations via ELISA PRRSV serum antibody titers peaked for all treatments at day 50, and then declined thereafter Serum antibody titers remained lower (P=.05) for animals fed HOC diet compared to those fed the CON diet. Animals fed the HOC diet experienced a delay (P=03) in measurable PRRSV serum antibody titers compared to those fed the CON diet. Also, it took longer for the PRRSV negative pigs fed HOC to seroconvert than the PRRSV negative pigs fed the CON diet. This dely may be attributed to effects of HOC on dust reduction affecting the aerosol transmission of PRRSV, and/or the biological effect HOC has on PRRSV, and/or the biological effect HOC has on PRRSV challenged pigs. The data from this study indicates that HOC delays the seroconversion of PRRSV challenged pigs, and may reduce the onse of PRRSV in growing pigs

General Static Solutions of 2-dimensional Einstein-Dilaton-Maxwell-Scalar Theories

General static solutions of effectively 2-dimensional Einstein-Dilaton-Maxwell-Scalar theories are obtained. Our model action includes a class of 2-d dilaton gravity theories coupled with a $U(1)$ gauge field and a massless scalar field. Therefore it also describes the spherically symmetric reduction of $d$-dimensional Einstein-Scalar-Maxwell theories. The properties of the analytic solutions are briefly discussed.Comment: 16 pages, Latex fil

Backward pion-nucleon scattering

A global analysis of the world data on differential cross sections and polarization asymmetries of backward pion-nucleon scattering for invariant collision energies above 3 GeV is performed in a Regge model. Including the $N_\alpha$, $N_\gamma$, $\Delta_\delta$ and $\Delta_\beta$ trajectories, we reproduce both angular distributions and polarization data for small values of the Mandelstam variable $u$, in contrast to previous analyses. The model amplitude is used to obtain evidence for baryon resonances with mass below 3 GeV. Our analysis suggests a $G_{39}$ resonance with a mass of 2.83 GeV as member of the $\Delta_{\beta}$ trajectory from the corresponding Chew-Frautschi plot.Comment: 12 pages, 16 figure

Test-retest Reliability Of Cerebral Blood Flow In Healthy Individuals Using Arterial Spin Labeling: Findings From The Embarc Study

Introduction—Previous investigations of test-retest reliability of cerebral blood flow (CBF) at rest measured with pseudo-continuous Arterial Spin Labeling (pCASL) demonstrated good reliability, but are limited by the use of similar scanner platforms. In the present study we examined test-retest reliability of CBF in regions implicated in emotion and the default mode network