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 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

Environmental Effects on Growing Swine Performance

The effects of environmental conditions on performance of growing pigs (30-50 kg) were studied over a four-week period. Pigs were exposed to natural occurring diurnal temperatures and a constant 32°C ambient temperature during normally hot weather conditions and constant 21 and 10°C ambient temperature conditions during cold weather. For each temperature treatment pigs were divided into single, 9 and 18 head per pen groups. The constant 32°C ambient temperature had a significant (P\u3c0.05) effect on average daily gain and feed intake. Average daily gains were reduced from 0.72 to 0.64 kg/d and average daily feed intake was reduced from 1.53kg/d to 1.36 kg/d when comparing pig performance from the naturally occurring diurnal to constant 32°C temperature treatments. The 10°C cold weather treatment had no significant {P\u3e0.05) effects on overall pig performance. Pigs from the 10°C treatment gained at a rate of 0. 72 vs 0.74 kg/d for pigs in the 21°C treatment. Average daily feed intake was 1.61 kg/d for pigs at 10°C versus 1.64 kg/d for pigs at 21°C. The 9 and 18 pigs per pen group size had no significant effect on pig performance in any of the temperature treatments. Pen microenvironments varied considerably with each temperature treatment. Pig and floor surface temperatures were significantly affected by temperature and group size. During the cold weather tests the pigs housed in the single pigpens had significantly (P\u3c0.0001) lower surface temperatures than the pigs from the 9 and 18 pigs per pen group. The objective of the study was to determine the effects of maintained warm or cold temperatures and group size on growing swine and characterize the pen environment for each condition

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

Effects of High Protein/low Carbohydrate Swine Diets During the Final Finishing Phase on Pork Muscle Quality

Pork color and water-holding capacity defects (pale, soft and exudative, or PSE pork) are functions of muscle pH and cost of the U.S. pork industry $60 million per year (Morgan et al., 1994). Pork with a low ultimate hP (pH\u3c5.5) has a paler color and lower water-holding capacity. Lactic acid build-up is responsible for lowering pH from 7.0, at the time of death, to 5.2-6.0 at 24h postmortem. Postmortem glycolysis produces lactic acid and can only occur in the presence of the substrate glycogen. Therefore, more glycogen in the muscle at slaughter will result in more lactic acid build up and a lower ultimate pH, which will result in a paler color and a lower water-holding capacity (Ellis et al, 1997) Consumption of carbohydrates is the main source of glucose in the blood (Guyton and Hall, 1996). In human studies conducted by Snitker et al., (1997) eight adult males were given one of two isoenergetic diets: a high-carbohydrate diet (75% of energy as carbohydrate, 15% as protein, and 10% as fat), or a low-carbohydrate diet (10% of energy as carbohydrate, 15% as protein, and 75% as fat) for three days. After the three day dietary maniuplation, glycogen content in the vastus lateralis muscle was significatnly lower for the low-carbohydrate subjects; 296 vs 426 mmol glucose/kg dry muscle, respectively (P\u3c0.001) (Snitker et al., 1997). Therefore, this study was conducted to determine if feeding ultra-high protein/low carbohydrate swine diets during the final finishing phase could reduce muscle glycogen and thereby imporve pork muscle quality

Crises and collective socio-economic phenomena: simple models and challenges

Financial and economic history is strewn with bubbles and crashes, booms and busts, crises and upheavals of all sorts. Understanding the origin of these events is arguably one of the most important problems in economic theory. In this paper, we review recent efforts to include heterogeneities and interactions in models of decision. We argue that the Random Field Ising model (RFIM) indeed provides a unifying framework to account for many collective socio-economic phenomena that lead to sudden ruptures and crises. We discuss different models that can capture potentially destabilising self-referential feedback loops, induced either by herding, i.e. reference to peers, or trending, i.e. reference to the past, and account for some of the phenomenology missing in the standard models. We discuss some empirically testable predictions of these models, for example robust signatures of RFIM-like herding effects, or the logarithmic decay of spatial correlations of voting patterns. One of the most striking result, inspired by statistical physics methods, is that Adam Smith's invisible hand can badly fail at solving simple coordination problems. We also insist on the issue of time-scales, that can be extremely long in some cases, and prevent socially optimal equilibria to be reached. As a theoretical challenge, the study of so-called "detailed-balance" violating decision rules is needed to decide whether conclusions based on current models (that all assume detailed-balance) are indeed robust and generic.Comment: Review paper accepted for a special issue of J Stat Phys; several minor improvements along reviewers' comment

Measurements of the Ratios B(Ds+→ηℓ+ν)/B(Ds+→ϕℓ+ν){\cal B}(D_s^+\to \eta\ell^+\nu)/{\cal B}(D_s^+\to \phi\ell^+\nu) and B(Ds+→η′ℓ+ν)/B(Ds+→ϕℓ+ν){\cal B}(D_s^+\to \eta'\ell^+\nu)/{\cal B}(D_s^+\to \phi\ell^+\nu)

Using the CLEO~II detector we measure ${\cal B}(D_s^+\to \eta e^+\nu)/{\cal B}(D_s^+\to \phi e^+\nu) =1.24\pm0.12\pm0.15$, ${\cal B}(D_s^+\to \eta' e^+\nu)/{\cal B}(D_s^+\to \phi e^+\nu) =0.43\pm0.11\pm0.07$ and ${\cal B}(D_s^+\to \eta' e^+\nu)/{\cal B}(D_s^+\to \eta e^+\nu) =0.35\pm0.09\pm0.07$. We find the vector to pseudoscalar ratio, ${\cal B}(D_s^+\to \phi e^+\nu)/{\cal B}(D_s^+\to (\eta+\eta') e^+\nu) =0.60\pm0.06\pm0.06$, which is similar to the ratio found in non strange $D$ decays.Comment: 11 page uuencoded postscript file, postscript file also available through http://w4.lns.cornell.edu/public/CLN

DES13S2cmm: the first superluminous supernova from the Dark Energy Survey

We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 +/- 0.001 based on the host-galaxy emission lines) and likely spectral type (type I). Using this redshift, we find M_U_peak = -21.05 +0.10 -0.09 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low metallicity (sub-solar), low stellar-mass host galaxy (log(M/M_sun) = 9.3 +/- 0.3); consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to fourteen similarly well-observed SLSNe-I in the literature and find it possesses one of the slowest declining tails (beyond +30 days rest frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2-0.3 magnitudes between +25 and +30 days after peak (rest frame) depending on redshift range studied; this could be important for 'standardising' such supernovae, as is done with the more common type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I - the radioactive decay of 56Ni, and a magnetar - and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 days in the rest frame of the supernova.Comment: Accepted by MNRAS (2015 January 23), 13 pages, 6 figures, 2 table