The effect of farming system on dairy cow cleanliness in the UK and implications to udder health

The cleanliness of dairy cows was assessed using a 20 point hygiene score system at different times in the year on 14 organic and 14 conventional farms in the UK. Overall, cows were dirtier during winter housing compared to summer grazing. Farming system had no effect on cow cleanliness when cows were at grass, but when housed in the winter, organic cows were more likely to be cleaner. There was a link between cow hygiene scores and milk hygiene, with herds having lower bulk tank somatic cell counts (BTSCC) tending to have cleaner cows. This relationship was strongest for the organic herds. There was no significant link between hygiene score and Bactoscan (BS) count or mastitis incidence

Lactobacillus fermentum (PCC®) supplementation and gastrointestinal and respiratory-tract illness symptoms: a randomised control trial in athletes

BACKGROUND Probiotics purportedly reduce symptoms of gastrointestinal and upper respiratory-tract illness by modulating commensal microflora. Preventing and reducing symptoms of respiratory and gastrointestinal illness are the primary reason that dietary supplementation with probiotics are becoming increasingly popular with healthy active individuals. There is a paucity of data regarding the effectiveness of probiotics in this cohort. The aim of this study was to evaluate the effectiveness of a probiotic on faecal microbiology, self-reported illness symptoms and immunity in healthy well trained individuals. METHODS Competitive cyclists (64 males and 35 females; age 35 ± 9 and 36 ± 9 y, VO2max 56 ± 6 and 52 ± 6 ml.kg-1.min-1, mean ± SD) were randomised to either probiotic (minimum 1 × 109 Lactobacillus fermentum (PCC®) per day) or placebo treatment for 11 weeks in a double-blind, randomised, controlled trial. The outcome measures were faecal L. fermentum counts, self-reported symptoms of illness and serum cytokines. RESULTS Lactobacillus numbers increased 7.7-fold (90% confidence limits 2.1- to 28-fold) more in males on the probiotic, while there was an unclear 2.2-fold (0.2- to 18-fold) increase in females taking the probiotic. The number and duration of mild gastrointestinal symptoms were ~2-fold greater in the probiotic group. However, there was a substantial 0.7 (0.2 to 1.2) of a scale step reduction in the severity of gastrointestinal illness at the mean training load in males, which became more pronounced as training load increased. The load (duration×severity) of lower respiratory illness symptoms was less by a factor of 0.31 (99%CI; 0.07 to 0.96) in males taking the probiotic compared with placebo but increased by a factor of 2.2 (0.41 to 27) in females. Differences in use of cold and flu medication mirrored these symptoms. The observed effects on URTI had too much uncertainty for a decisive outcome. There were clear reductions in the magnitude of acute exercise-induced changes in some cytokines. CONCLUSION L. fermentum may be a useful nutritional adjunct for healthy exercising males. However, uncertainty in the effects of supplementation on URTI and on symptoms in females needs to be resolved. TRIAL REGISTRATION The trial was registered in the Australia and New Zealand Clinical Trials Registry (ACTRN12611000006943).The study was funded by Christian Hansen A/S, Probiomics and the Australian Institute of Sport

Epithelial Cell Coculture Models for Studying Infectious Diseases: Benefits and Limitations

Countless in vitro cell culture models based on the use of epithelial cell types of single lineages have been characterized and have provided insight into the mechanisms of infection for various microbial pathogens. Diverse culture models based on disease-relevant mucosal epithelial cell types derived from gastrointestinal, genitourinary, and pulmonary organ systems have delineated many key host-pathogen interactions that underlie viral, parasitic, and bacterial disease pathogenesis. An alternative to single lineage epithelial cell monoculture, which offers more flexibility and can overcome some of the limitations of epithelial cell culture models based on only single cell types, is coculture of epithelial cells with other host cell types. Various coculture models have been described, which incorporate epithelial cell types in culture combination with a wide range of other cell types including neutrophils, eosinophils, monocytes, and lymphocytes. This paper will summarize current models of epithelial cell coculture and will discuss the benefits and limitations of epithelial cell coculture for studying host-pathogen dynamics in infectious diseases

Mucosal Immunization with the Moraxella Catarrhalis Porin M35 Induces Enhanced Bacterial Clearance from the Lung: A Possible Role for Opsonophagocytosis

Moraxella catarrhalis is a significant cause of respiratory tract infection against which a vaccine is sought. Several outer membrane proteins are currently under investigation as potential vaccine antigens, including the porin M35. We have previously shown that the third external loop of M35 was immunodominant over the remainder of the protein for antibody produced in mice against the refolded recombinant protein. However, as this loop is predicted to fold inside the porin channel we also predicted that it would not be accessible to these antibodies when M35 is expressed on the surface of the bacteria in its native conformation. This study investigated the functional activity of antibodies against M35 and those specific for the loop 3 region of M35 in vitro and in vivo. Antisera from mice immunized with M35 or the loop 3-deletion, M35loop3−, recombinant proteins were not bactericidal but did have enhanced opsonic activity, whereas antibodies raised against the loop 3 peptide were not opsoniszing indicating that the immunodominant loop 3 of M35 was not accessible to antibody as we had previously predicted. Mucosal immunization with M35, M35 that had an antigenically altered loop 3 [M35(ID78)] and M35loop3− enhanced the clearance of M. catarrhalis from the lungs of mice challenged with live M. catarrhalis. The in vivo clearance of bacteria in the mice with the M35-derived protein constructs correlated significantly (p < 0.001) with the opsonic activity assessed an in vitro opsonophagocytosis assay. This study has demonstrated that the immunodominant B-cell epitope to loop 3 of the M. catarrhalis outer membrane protein M35 is not associated with immune protection and that M35-specific antibodies are not bactericidal but are opsoniszing. The opsoniszing activity correlated with in vivo clearance of the bacteria suggesting that opsoniszing antibody may be a good correlate of immune protection

The effect of exercise on innate mucosal immunity

METHODS The authors conducted a prospective observational study comparing salivary lactoferrin and lysozyme concentration over 5 months (chronic changes) in elite rowers (n=17, mean age 24.3+/-4.0 years) with sedentary individuals (controls) (n=18, mean age=27.2+/-7.1 years) and a graded exercise test to exhaustion (acute changes) with a cohort of elite rowers (n=11, mean age 24.7+/-4.1). RESULTS Magnitudes of differences and changes were interpreted as a standardised (Cohen's) effect size (ES). Lactoferrin concentration in the observational study was approximately 60% lower in rowers than control subjects at baseline (7.9+/-1.2 microg/ml mean+/-SEM, 19.4+/-5.6 microg/ml, p=0.05, ES=0.68, 'moderate') and at the midpoint of the season (6.4+/-1.4 microg/ml mean +/- SEM, 21.5+/-4.2 microg/ml, p=0.001, ES=0.89, 'moderate'). The concentration of lactoferrin at the end of the study was not statistically significant (p=0.1) between the groups. There was no significant difference between rowers and control subjects in lysozyme concentration during the study. There was a 50% increase in the concentration of lactoferrin (p=0.05, ES=1.04, 'moderate') and a 55% increase in lysozyme (p=0.01, ES=3.0, 'very large') from pre-exercise to exhaustion in the graded exercise session. CONCLUSION Lower concentrations of these proteins may be indicative of an impairment of innate protection of the upper respiratory tract. Increased salivary lactoferrin and lysozyme concentration following exhaustive exercise may be due to a transient activation response that increases protection in the immediate postexercise period

Towards a modeling of the time dependence of contact area between solid bodies

I present a simple model of the time dependence of the contact area between solid bodies, assuming either a totally uncorrelated surface topography, or a self affine surface roughness. The existence of relaxation effects (that I incorporate using a recently proposed model) produces the time increase of the contact area $A(t)$ towards an asymptotic value that can be much smaller than the nominal contact area. For an uncorrelated surface topography, the time evolution of $A(t)$ is numerically found to be well fitted by expressions of the form [$A(\infty)-A(t)]\sim (t+t_0)^{-q}$, where the exponent $q$ depends on the normal load $F_N$ as $q\sim F_N^{\beta}$, with $\beta$ close to 0.5. In particular, when the contact area is much lower than the nominal area I obtain $A(t)/A(0) \sim 1+C\ln(t/t_0+1)$, i.e., a logarithmic time increase of the contact area, in accordance with experimental observations. The logarithmic increase for low loads is also obtained analytically in this case. For the more realistic case of self affine surfaces, the results are qualitatively similar.Comment: 18 pages, 9 figure

Some recent radio talks.

Myxomatosis is losing its punch - By A. R. TOMLINSON, Chief Vermin Control Officer The results of the testing of field strains of myxomatosis just released by the Australian National University are of vital importance to every farmer in Western Australia. They show clearly that the predicted decline in the effectiveness of myxomatosis has occurred. Worse still, they reveal that the decline has been more rapid in some areas than observers anticipated. The importance of good seed in vegetable production. - By T. WACHTEL, Vegetable Adviser, Horticultural Division The seed is the foundation of the crop that eventually is to be harvested. As an American textbook on vegetable vegetable growing puts it: Within the seed coat may be locked up the key to future success or failure. A vegetable crop can be much poorer than the seed, but it cannot be better. Water conservation on the farm - By J. W. LEWIS, Irrigation Adviser, Bunbury Water conservation on the farm is becoming increasingly important in this State, and on most properties in the South-West water can be conserved easily and economically. Coupled with the use of modern spray irrigation systems, this trend may well revolutionise farming methods in years to come and lead the way to greater agricultural prosperity. Itch mite in sheep - By C. R. TOOP, Chief Veterinary Surgeon During the past 12 months there has been a sharp rise in the incidence of itch mite and many cases have been reported both from sheep markets and individual properties. The symptoms of itch mite infestation are very similar to those produced by hce but, unlike the sheep louse, the itch mite is invisible to the naked eye and the microscopic examination of scrapings taken from the skin after the wool has been closely clipped is necessary for its detection. Orchard irrigation - By J. CRIPPS, Horticultural Adviser There are no fruits grown in Western Australia which do not give larger crops if irrigated, although the majority of fruit growers do not have irrigation installations. Powdery mildew diseases in the home garden - By OLGA M. GOSS, B.Sc. Hons., Plant Pathologist Most of you will be only too familiar with the powdery mildew diseases which occur so frequently during the warmer months in your gardens. The most common plants badly affected by these diseases are grape vines, roses, hydrangeas, delphinium, Iagerstroemia and melons of various types. Cat Flu - A matter of serious concern - By J. SHILKIN, B.V.Sc, Veterinary Surgeon The importance of cats in the community is not generally realised by the public, yet severe epidemics among the feline population should be a matter of considerable concern. The presence of a reasonably large cat population in our cities is most important in keeping rat and mice numbers down to a low level, and their importance on farming properties is too well known to need any comment. Rat-borne diseases do occur m man in Australia and rats are always a potential danger as carriers and spreaders of some extremely serious diseases of man. Even good farmers can cause erosion. - By BRIAN MARSH, B.Sc. (Agric), Soil Conservation Adviser The particular aspects of soil conservation I am to discuss has not been publicised before, and the suggestions contained in this talk may be of use to you during seeding operations this year. It is often asked, Will the use of clover really prevent erosion

Symmetric equilibria in double auctions with markdown buyers and markup sellers

Zhan and Friedman (2007) study double auctions where buyers and sellers are constrained to using simple markdown and markup rules. In spite of the alleged symmetry in roles and assumptions, buyers are shown to have the upper hand both in the call market and in the continuous double auction. We replicate the study and show that their formulation of the sellers’ markup strategies, while seemingly natural, exhibits a hidden asymmetry.We introduce a symmetric set of markup strategies for the sellers and show how it explains away the paradox of buyers’ advantage in three different double-sided market protocols

Effects of cortisol and dexamethasone on insulin signalling pathways in skeletal muscle of the ovine fetus during late gestation.

Before birth, glucocorticoids retard growth, although the extent to which this is mediated by changes in insulin signalling pathways in the skeletal muscle of the fetus is unknown. The current study determined the effects of endogenous and synthetic glucocorticoid exposure on insulin signalling proteins in skeletal muscle of fetal sheep during late gestation. Experimental manipulation of fetal plasma glucocorticoid concentration was achieved by fetal cortisol infusion and maternal dexamethasone treatment. Cortisol infusion significantly increased muscle protein levels of Akt2 and phosphorylated Akt at Ser473, and decreased protein levels of phosphorylated forms of mTOR at Ser2448 and S6K at Thr389. Muscle GLUT4 protein expression was significantly higher in fetuses whose mothers were treated with dexamethasone compared to those treated with saline. There were no significant effects of glucocorticoid exposure on muscle protein abundance of IR-β, IGF-1R, PKCζ, Akt1, calpastatin or muscle glycogen content. The present study demonstrated that components of the insulin signalling pathway in skeletal muscle of the ovine fetus are influenced differentially by naturally occurring and synthetic glucocorticoids. These findings may provide a mechanism by which elevated concentrations of endogenous glucocorticoids retard fetal growth

The LAGUNA design study- towards giant liquid based underground detectors for neutrino physics and astrophysics and proton decay searches

The feasibility of a next generation neutrino observatory in Europe is being considered within the LAGUNA design study. To accommodate giant neutrino detectors and shield them from cosmic rays, a new very large underground infrastructure is required. Seven potential candidate sites in different parts of Europe and at several distances from CERN are being studied: Boulby (UK), Canfranc (Spain), Fr\'ejus (France/Italy), Pyh\"asalmi (Finland), Polkowice-Sieroszowice (Poland), Slanic (Romania) and Umbria (Italy). The design study aims at the comprehensive and coordinated technical assessment of each site, at a coherent cost estimation, and at a prioritization of the sites within the summer 2010.Comment: 5 pages, contribution to the Workshop "European Strategy for Future Neutrino Physics", CERN, Oct. 200