DALYs, dollars and dogs: how best to analyse the economics of controlling zoonoses.

Decision-makers increasingly require comprehensive economic metrics summarising and comparing the benefits and costs of controlling zoonotic diseases. The impact of disease in people is conventionally quantified in non-monetary terms, usually a disability-adjusted life year (DALY), whereas the losses due to disease in animals, particularly livestock, are quantified in monetary terms. The potential for the development of a non-monetary metric for ill health in animals, based on life years lost and disability, is discussed and rejected. Within and across animal species and livestock production systems, maximising life spans is not a consistent goal and morbidity/disabilities have very different weights and often lead to culling. By relating livestock losses to a measure of national income forgone, the recently developed alternative of converting monetary losses due to livestock illness into an animal loss equivalent (ALE) provides a viable solution. Based on this, the literature on the economics of controlling zoonoses is revisited and four options for quantifying and comparing benefits and costs are examined and illustrated using numerical examples. These are i) the simplistic grouping of all monetary elements and their comparison to DALYs averted (described as the aggregate net cost method), ii) the separable costs method, iii) the use of ALEs to convert all benefits to a non-monetary equivalent, termed the zoonotic DALY (zDALY), or iv) the use of a full monetary cost-benefit analysis, based on converting DALYs to a monetary equivalent. The strengths and weaknesses of each are discussed. For effective prioritisation and decision-making, it is vital that an analytical approach is widely adopted which yields consistent results and which supports the control of zoonoses.

Les décideurs politiques sont de plus en plus dépendants de méthodes exhaustives de mesure économique permettant de synthétiser et de comparer les avantages et les coûts de la lutte contre les zoonoses. Par convention, l'impact des maladies humaines est quantifié en des termes non monétaires, à savoir, le plus souvent, en « années de vie corrigées de l'incapacité ¼ (DALY), tandis que les pertes dues aux maladies animales, en particulier celles affectant les animaux d'élevage, sont quantifiées en termes monétaires. Dans cet article, les auteurs envisagent (et réfutent) la possibilité de mettre en oeuvre un système de mesure non monétaire des problèmes sanitaires chez les animaux qui soit basé sur les années de vie perdues ou d'incapacité. La longévité n'est pas un objectif uniformément recherché dans tous les systèmes de production, ni pour toutes les espèces animales, voire pour tous les individus au sein d'une même espèce, et la morbidité et l'incapacité représentent des fardeaux très variables, conduisant souvent à l'abattage. Parce qu'elle relie les pertes animales à une mesure de la réduction du revenu intérieur entraînée, la récente proposition de convertir les pertes monétaires dues aux maladies du bétail en un « équivalent pertes animales ¼ (indicateur ALE : animal loss equivalent) constitue une solution viable. À partir de ces considérations, les auteurs examinent la littérature dédiée aux aspects économiques de la lutte contre les zoonoses en détaillant quatre méthodes possibles pour en quantifier et comparer les avantages et les coûts, avec des exemples chiffrés. Ces possibilités sont : i) le simple regroupement de tous les éléments monétaires et leur comparaison en termes de DALY évitées (méthode dite de la présentation agrégée des coûts nets) ; ii) la méthode des coûts séparables ; iii) l'utilisation d'un indicateur ALE pour convertir l'ensemble des bénéfices en leur équivalent non monétaire, désigné sous le terme de DALY zoonotique (zDALY) ; iv) le recours à une analyse monétaire coûts-avantages exhaustive, après avoir converti les DALY en leur équivalent monétaire. Les auteurs font ressortir les atouts et les faiblesses de chacune de ces méthodes. La priorisation et la prise de décisions gagneront en efficacité si les décideurs adoptent et appliquent largement une approche analytique permettant d'obtenir des résultats cohérents et de renforcer la lutte contre les zoonoses.

Cada vez más, las instancias decisorias necesitan parámetros econométricos integrales, que sirvan para sintetizar y comparar los costos y beneficios de la lucha contra enfermedades zoonóticas. Convencionalmente, los efectos de una enfermedad en las personas se cuantifican en términos no monetarios, por lo general en forma de «años de vida ajustados en función de la discapacidad¼ (AVAD), mientras que las pérdidas inducidas por las enfermedades en animales, en particular el ganado, se cuantifican en valores monetarios. Los autores examinan y descartan la posible definición de parámetros no monetarios, basados en los años de vida perdidos y en la discapacidad, para cuantificar problemas zoosanitarios. Con independencia de la especie animal o el sistema de producción ganadera de que se trate, el de lograr una longevidad máxima no es un objetivo habitual, y los niveles de morbilidad o discapacidad, que suelen desembocar en el sacrificio sanitario, tienen un peso muy variable. En fechas recientes ha aparecido una alternativa que, al establecer una relación entre las pérdidas de ganado y una medida de la renta nacional prevista, ofrece una solución viable: se trata de convertir las pérdidas monetarias causadas por enfermedades del ganado en un «equivalente a las pérdidas animales¼ (animal loss equivalent: ALE). Partiendo de esta idea, los autores repasan la bibliografía sobre la economía de la lucha contra las zoonosis y examinan cuatro opciones para cuantificar y comparar beneficios y costos, ilustrándolas con ejemplos numéricos. Se trata de las siguientes: i) el simplificador procedimiento de agrupar todos los elementos monetarios y compararlos con los AVAD evitados (método que describen como del «costo agregado neto¼); ii) el método de los costos específicos; iii) el uso de «equivalentes a las pérdidas animales¼ para convertir todos los beneficios en un equivalente no monetario que denominan AVAD por zoonosis; y iv) el uso de un análisis monetario completo de la relación entre beneficios y costos, basado en la conversión de los AVAD en un equivalente monetario. A continuación examinan los puntos fuertes y débiles de cada uno de esos métodos, y concluyen que para fijar prioridades y adoptar decisiones con eficacia es vital aplicar de forma generalizada un mismo planteamiento analítico, que arroje resultados coherentes y ayude así a combatir las zoonosis.

High-energy anomaly in the angle-resolved photoemission spectra of Nd(2-x)Ce(x)CuO4: evidence for a matrix element effect.

We use polarization-dependent angle-resolved photoemission spectroscopy (ARPES) to study the high-energy anomaly (HEA) in the dispersion of Nd(2-x)Ce(x)CuO4, x=0.123. We find that at particular photon energies the anomalous, waterfall-like dispersion gives way to a broad, continuous band. This suggests that the HEA is a matrix element effect: it arises due to a suppression of the intensity of the broadened quasiparticle band in a narrow momentum range. We confirm this interpretation experimentally, by showing that the HEA appears when the matrix element is suppressed deliberately by changing the light polarization. Calculations of the matrix element using atomic wave functions and simulation of the ARPES intensity with one-step model calculations provide further evidence for this scenario. The possibility to detect the full quasiparticle dispersion further allows us to extract the high-energy self-energy function near the center and at the edge of the Brillouin zone.

Probing the complex ion structure in liquid carbon at 100 GPa.

We present the first direct experimental test of the complex ion structure in liquid carbon at pressures around 100 GPa, using spectrally resolved x-ray scattering from shock-compressed graphite samples. Our results confirm the structure predicted by ab initio quantum simulations and demonstrate the importance of chemical bonds at extreme conditions similar to those found in the interiors of giant planets. The evidence presented here thus provides a firmer ground for modeling the evolution and current structure of carbon-bearing icy giants like Neptune, Uranus, and a number of extrasolar planets.

Persistence of brucellosis in pastoral systems.

Regarded as a highly contagious, zoonotic disease with worldwide distribution, brucellosis is endemic in many countries and settings and is responsible for a considerable economic and health-related burden. Limited information is available on the persistence and prevalence of brucellosis in pastoral communities, due to the difficulty in gathering information and to their mobility. However, since these communities are economically and culturally dependent on livestock, it is important to further determine the cause of persistent disease and develop possible methods for its management. The two main objectives of this paper are to review the literature, identifying various epidemiological and social factors that affect the persistence of brucellosis in pastoral ecosystems, and determine prevalence estimates within these communities. The general trend of the summarised studies indicates low-level, relatively stable transmission of brucellosis in pastoral areas, when compared to transmission in intensive and semi-intensive peri-urban production systems. A formal mathematical analysis can be undertaken using matrix models or coupled differential equations. This allows an examination of the various conditions under which the number of diseased, infected or exposed animals remains stable. The authors examined an existing mathematical differential equation model for brucellosis in Mongolia for its equilibrium conditions and found it reasonably robust, though clearly more data are needed to estimate threshold densities for brucellosis transmission in other regions of the world. However, the results indicate the importance of livestock demographic determinants for brucellosis persistence. The paper concludes that brucellosis remains largely persistent in pastoral areas of the world, despite (varying) control efforts. Plans to control brucellosis in pastoral settings should include ecological considerations, such as sustaining ecosystem services in pastoral areas. This approach would include placing limitations on livestock stocking density, land reform, improved governance and integrated social and economic development.

Peripheral nerve regeneration in rats using nerve graft in a vein conduit pre-filled with platelet-rich fibrin (PRF).

Treatment of peripheral nerve injury is not always satisfactory. To improve results, specific adjuvant methods have been used, such as platelet-rich fibrin (PRF) and vein conduits. The goal of this study was to assess whether use of PRF and vein conduits after nerve suture improves nerve regeneration as measured by a functional score and histomorphometry analysis. Ten isogenic spontaneously hypertensive rats were randomly assigned to 4 experimental procedures: 1) Sham group (n = 10); 2) Nerve graft (NG) group (n = 10); 3) Nerve graft covered with a vein conduit (NGVC) (n = 10); and 4) Nerve graft covered with a vein conduit pre-filled with PRF (NGVCP) (n = 10). Nerve repair results were evaluated on: sciatic functional index (SFI) at 0, 30, 60 and 90 days; morphometric and morphologic analysis of the distal nerve; and histological analysis of Fluoro-Gold® stained motor neurons in the anterior horn of the spinal cord. Compared to the Sham control group, the NGVC and NGVCP groups exhibited lower SFI on all measures. The NGVC group showed improvement in SFI at day 90, which was significant compared to the NG group. Fiber and axon diameters were comparable in the NGVC and NGVCP groups, which were both significantly lower than in the Sham and NG groups. Significant improvement was expected with PRF, but in fact the release of factors from this substance was not as effective as hoped.

Electronic states and the influence of oxygen addition on the optical absorption behaviour of manganese phthalocyanine.

The effects of electronic states and air exposure on the spectroscopic properties of manganese phthalocyanine (MnPc) have been examined. The observed features of the Q-band in the absorption spectra can be explained by intrinsic electronic properties of MnPc, i.e., the formation of singly charged molecules by charge transfer excitations. However, the reaction of MnPc with atmospheric molecular oxygen leads to deviations in peak intensities but does not change the fundamental characteristics of the spectra. Nevertheless, the reaction with oxygen changes the spin state from S = 3/2 to S = 1/2. X-ray diffraction measurements also indicate a slow diffusion process of the oxygen into the MnPc crystal. We discuss both influences to explain the behaviour of MnPc in various spectroscopic methods (EELS, ellipsometry, PES). Furthermore, we support the experimental investigations by detailed ab-initio calculations of spectroscopic properties using methods of the density functional theory framework.

Transmission dynamics and economics of rabies control in dogs and humans in an African city.

Human rabies in developing countries can be prevented through interventions directed at dogs. Potential cost-savings for the public health sector of interventions aimed at animal-host reservoirs should be assessed. Available deterministic models of rabies transmission between dogs were extended to include dog-to-human rabies transmission. Model parameters were fitted to routine weekly rabid-dog and exposed-human cases reported in N'Djaména, the capital of Chad. The estimated transmission rates between dogs (beta(d)) were 0.0807 km2/(dogs x week) and between dogs and humans (beta(dh)) 0.0002 km2/(dogs x week). The effective reproductive ratio (R(e)) at the onset of our observations was estimated at 1.01, indicating low-level endemic stability of rabies transmission. Human rabies incidence depended critically on dog-related transmission parameters. We simulated the effects of mass dog vaccination and the culling of a percentage of the dog population on human rabies incidence. A single parenteral dog rabies-mass vaccination campaign achieving a coverage of least 70% appears to be sufficient to interrupt transmission of rabies to humans for at least 6 years. The cost-effectiveness of mass dog vaccination was compared to postexposure prophylaxis (PEP), which is the current practice in Chad. PEP does not reduce future human exposure. Its cost-effectiveness is estimated at US $46 per disability adjusted life-years averted. Cost-effectiveness for PEP, together with a dog-vaccination campaign, breaks even with cost-effectiveness of PEP alone after almost 5 years. Beyond a time-frame of 7 years, it appears to be more cost-effective to combine parenteral dog-vaccination campaigns with human PEP compared to human PEP alone.

[Transmission dynamics and cost-effectiveness of rabies control in dogs and humans in an African city]. / Dynamique de transmission et coût de la lutte contre la rage chez les chiens et les hommes dans une ville Africaine.

Control of human rabies in developing countries depends on prevention in dogs. The purpose of this study was to evaluate the cost-saving potential for the public health sector of intervention to control rabies in animal-host reservoirs. An existing deterministic model was adapted to allow study of dog-to-human rabies transmission. Model parameters were fitted to data from routine weekly reports on the number of rabid dogs and human rabies exposures in N'Djamena, Chad. At the onset of study, the estimated effective reproductive ratio (Re) was 1.01 indicating stable low-level endemic rabies transmission. Simulations were performed to determine what effects mass vaccination and culling of dogs would have on the incidence of human rabies. Findings showed that a mass campaign allowing single parenteral vaccination of at least 70% of the canine population would be sufficient to interrupt transmission of rabies to humans for at least 6 years. The cost-effectiveness of mass dog vaccination was compared to that of "postexposure prophylaxis" (PEP) which would not reduce future human exposure. Results showed that a sustained 5-year PEP program together with a dog-vaccination campaign would be as cost-effective as PEP alone. Beyond a time-frame of 7 years, combining parenteral dog vaccination campaigns with human PEP appeared to be more cost-effective than human PEP alone.

Progressive secondary exo-focal dopaminergic neurodegeneration occurs in not directly connected midbrain nuclei after pure motor-cortical stroke.

Transsynaptic anterograde and retrograde degeneration of neurons and neural fibers are assumed to trigger local excitotoxicity and inflammatory processes. These processes in turn are thought to drive exo-focal neurodegeneration in remote areas connected to the infarcted tissue after ischemic stroke. In the case of middle cerebral artery occlusion (MCAO), in which striato-nigral connections are affected, the hypothesis of inflammation-induced remote neurodegeneration is based on the temporal dynamics of an early appearance of inflammatory markers in midbrain followed by dopaminergic neuronal loss. To test the hypothesis of a direct transsynaptic mediation of secondary exo-focal post-ischemic neurodegeneration, we used a photochemical induction of a stroke (PTS) in Sprague-Dawley rats restricted to motor cortex (MC), thereby sparing the striatal connections to dopaminergic midbrain nuclei. To dissect the temporal dynamics of post-ischemic neurodegeneration, we analyzed brain sections harvested at day 7 and 14 post stroke. Here, an unexpectedly pronounced and widespread loss of dopaminergic neurons occurred 14 days after stroke also affecting dopaminergic nuclei that are not directly coupled to MC. Since the pattern of neurodegeneration in case of a pure motor stroke is similar to a major stroke including the striatum, it is unlikely that direct synaptic coupling is a prerequisite for delayed secondary exo-focal post ischemic neurodegeneration. Furthermore, dopaminergic neurodegeneration was already detected by Fluoro-Jade C staining at day 7, coinciding with a solely slight inflammatory response. Thus, inflammation cannot be assumed to be the primary driver of exo-focal post-ischemic cell death. Moreover, nigral substance P (SP) expression indicated intact striato-nigral innervation after PTS, whereas opposing effects on SP expression after striatal infarcts argue against a critical role of SP in neurodegenerative or inflammatory processes during exo-focal neurodegeneration.

The role of seagrass vegetation and local environmental conditions in shaping benthic bacterial and macroinvertebrate communities in a tropical coastal lagoon.

We investigated the influence of seagrass canopies on the benthic biodiversity of bacteria and macroinvertebrates in a Red Sea tropical lagoon. Changes in abundance, number of taxa and assemblage structure were analyzed in response to seagrass densities (low, SLD; high, SHD; seagrasses with algae, SA), and compared with unvegetated sediments. Biological and environmental variables were examined in these four habitats (hereafter called treatments), both in the underlaying sediments and overlaying waters, at three randomly picked locations in March 2017. Differences between treatments were more apparent in the benthic habitat than in the overlaying waters. The presence of vegetation (more than its cover) and changes in sedimentary features (grain size and metals) at local scales influenced the observed biological patterns, particularly for macroinvertebrates. Of note, the highest percentage of exclusive macroinvertebrate taxa (18% of the gamma diversity) was observed in the SHD treatment peaking in the SA for bacteria. Benthic macroinvertebrates and bacteria shared a generally low number of taxa across treatments and locations; approximately, 25% of the gamma diversity was shared among all treatments and locations for macrofauna, dropping to 11% for bacteria. Given the low overlap in the species distribution across the lagoon, sustaining the connectivity among heterogeneous soft sediment habitats appears to be essential for maintaining regional biodiversity. This study addresses a current scientific gap related to the relative contributions of vegetated and unvegetated habitats to biodiversity in tropical regions.

Electronic properties of potassium doped FePc from electron energy-loss spectroscopy.

We have studied the electronic structure of potassium doped iron phthalocyanine (FePc) phases using electron energy-loss spectroscopy. The electronic excitation spectrum of FePc is rather complex and comprises both pi-pi( *) transitions of the phthalocyanine ligand and transitions that involve the Fe 3d orbitals. This allows deeper insight into the orbital occupation in FePc. Potassium doping, i.e., the addition of electrons to the FePc molecules causes significant changes in the electronic excitations, which signal filling of pi( *) as well as Fe 3d orbitals.

Investigations on iron bioavailability of different sources and supply levels in piglets.

Two experiments were conducted to investigate the iron bioavailability of different sources and supply levels in piglets. In experiment 1, the influence of feeding an iron deficient basal diet or the basal diet supplemented with 28 ppm Fe either in form of Fe-chelate, crystalline Fe-glycinate, or Fe-sulphate on apparent iron digestibility and on blood parameters was determined. In experiment 2, a dose-response approach was used to determine the effects of supplementing an iron-deficient basal diet with 30, 60, or 90 ppm of Fe either in form of crystalline Fe-glycinate or Fe-sulphate on digestibility of Fe, growth and blood parameters. In experiment 1, comparison of iron sources revealed a tendency (0.05 < p < 0.1) for a higher Fe digestibility from Fe-glycinate (40.9%) compared with Fe-chelate (30.8%) or Fe-sulphate (30.7%). Fe-balance was higher (p < 0.05) for Fe-glycinate compared with Fe-sulphate but iron balance was similar for iron sulphate and iron chelate. Those results, however, were not reflected in data of blood parameters. In experiment 2, iron digestibility, blood parameters and performance were significantly (p < 0.05) influenced by iron supply. Effects of iron source on digestibility of iron were lower than observed in the first experiment.

Coral reef degradation affects the potential for reef recovery after disturbance.

The loss of coral cover is often accompanied by an increase of benthic algae, a decline in biodiversity and habitat complexity. However, it remains unclear how surrounding communities influence the trajectories of re-colonization between pulse disturbance events. Over a 12-month field experiment in the central Red Sea, we examined how healthy (hard-coral dominated) and degraded (algae-dominated) reef areas influence recruitment and succession patterns of benthic reef foundation communities on bare substrates. Crustose coralline algae and other calcifiers were important colonizers in the healthy reef area, promoting the accumulation of inorganic carbon. Contrary, substrates in the degraded area were predominantly colonized by turf algae, lowering the accumulation of inorganic carbon by 178%. While coral larvae settlement similarly occurred in both habitats, degraded areas showed 50% fewer recruits. Our findings suggest that in degraded reefs the replenishment of adult coral populations is reduced due to recruitment inhibition through limited habitat complexity and grazing pressure, thereby restraining reef recovery.

Transverse resonance island buckets for synchrotron-radiation based electron time-of-flight spectroscopy.

At the Metrology Light Source (MLS), the compact electron storage ring of the Physikalisch-Technische Bundesanstalt (PTB) with a circumference of 48 m, a specific operation mode with two stable closed orbits for stored electrons was realized by transverse resonance island buckets. One of these orbits is closing only after three turns. In combination with single-bunch operation, the new mode was applied for electron time-of-flight spectroscopy with an interval of the synchrotron radiation pulses which is three times the revolution period at the MLS of 160 ns. The achievement is of significant importance for PTB's future programs of angular-resolved electron spectroscopy with synchrotron radiation and similar projects at other compact electron storage rings. The scheme applied here for selecting the photons originating from a particular orbit by optical imaging has been used before in fs slicing applications and may be relevant for the BESSY VSR project of the Helmholtz-Zentrum Berlin.

Finding DNA regulatory motifs within unaligned noncoding sequences clustered by whole-genome mRNA quantitation.

Whole-genome mRNA quantitation can be used to identify the genes that are most responsive to environmental or genotypic change. By searching for mutually similar DNA elements among the upstream non-coding DNA sequences of these genes, we can identify candidate regulatory motifs and corresponding candidate sets of coregulated genes. We have tested this strategy by applying it to three extensively studied regulatory systems in the yeast Saccharomyces cerevisiae: galactose response, heat shock, and mating type. Galactose-response data yielded the known binding site of Gal4, and six of nine genes known to be induced by galactose. Heat shock data yielded the cell-cycle activation motif, which is known to mediate cell-cycle dependent activation, and a set of genes coding for all four nucleosomal proteins. Mating type alpha and a data yielded all of the four relevant DNA motifs and most of the known a- and alpha-specific genes.

Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil).

Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ(13)Corg and δ(15)N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

Lower limits of fluorescein and indocyanine green dye for digital cSLO fluorescence angiography.

BACKGROUND: With the advent of digital confocal scanning laser ophthalmoscopy it is possible to detect low levels of fluorescence. Here we used a novel confocal scanning laser ophthalmoscope (cSLO) to determine lower limits of dye required for fluorescein (FL) and indocyanine green (ICG) angiography. METHODS: A cSLO (Heidelberg retina angiograph 2, Heidelberg Engineering, Dossenheim, Germany) with an optically pumped solid state laser (488 nm) for FL and a diode laser (790 nm) for ICG angiography (FL/ICG-A) was used. 62 FL-As were performed in 53 patients and 45 ICG-As were performed in 39 patients with neovascular age related macular degeneration. The volume and overall dye content of bolus injections was gradually tapered (FL: 500 mg, 250 mg, 200 mg, 166 mg, 100 mg; ICG: 25 mg, 20 mg, 15 mg, 10 mg, 5 mg, 2.5 mg), while dye concentrations were kept constant at 100 mg/ml for FL and at 5 mg/ml for ICG. Images were obtained 1, 5, 15, and 30 minutes after dye injection. Image quality was evaluated by two independent readers using standardised criteria. RESULTS: For amounts down to 166 mg for FL and to 5 mg for ICG, sufficient image quality was achieved during all phases following injection. Only late phase images showed less contrast compared to typically used dye amounts, which was irrelevant for interpretation and clinical management. CONCLUSIONS: With the increased sensitivity of this novel cSLO system, amounts of injected dye during FL-A can be reduced to one third for FL and to one fifth for ICG without relevant loss of image quality or information compared to conventionally used dye levels. These amounts can be used for routine angiography and allow relevant savings for units performing FL-A.

Dietary preferences for feeds varying in threonine concentration by the piglet.

Two choice feeding trials were carried out to investigate if weaned piglets prefer feeds varying in threonine (Thr) content. In exp 1, two control groups were fed either a 0.57% Thr (negative control) or a 0.67% Thr (positive control) feed. Two other groups had the choice from 2 feeds containing 0.57% or 0.62% Thr (Thr-choice 1) and 0.57% or 0.67% Thr (Thr-choice 2). In exp 2 the two control groups were fed either a 0.50% Thr (negative control) or a 0.62% Thr (positive control) feed and the Thr-choice groups had the choice from 2 feeds containing 0.50% or 0.56% (Thr-choice 1) and 0.50% or 0.62% Thr (Thr-choice 2), respectively. In exp 1, animals of the Thr-choice 1 showed a significant preference for the feed with the higher Thr content but in the Thr-choice 2, both feeds on offer were chosen at random. In exp 2 the preference for the higher Thr feeds in the Thr-choice groups 1 and 2 was on average 71% and 72%, respectively. In both experiments, the data of growth performance and plasma amino acid and urea pattern indicated a suboptimal Thr supply in the negative control and the Thr-choice 1 group. It is concluded that piglets are able to detect metabolic changes caused by a marginal Thr supply and that they change their feeding behaviour in order to overcome deficiency.

A model of animal-human brucellosis transmission in Mongolia.

We developed a dynamic model of livestock-to-human brucellosis transmission in Mongolia. The compartmental model considers transmission within sheep and cattle populations and the transmission to humans as additive components. The model was fitted to demographic and seroprevalence data (Rose Bengal test) from livestock and annually reported new human brucellosis cases in Mongolia for 1991-1999 prior to the onset of a mass livestock-vaccination campaign (S19 Brucella abortus for cattle and Rev 1 Brucella melitensis for sheep and goat). The vaccination effect was fitted to livestock- and human-brucellosis data from the first 3 years of the vaccination campaign (2000-2002). Parameters were optimized on the basis of the goodness-of-fit (assessed by the deviance). The simultaneously fitted sheep-human and cattle-human contact rates show that 90% of human brucellosis was small-ruminant derived. Average effective reproductive ratios for the year 1999 were 1.2 for sheep and 1.7 for cattle.

[cSLO digital fundus autofluorescence imaging]. / cSLO-Fundusautofluoreszenz-Imaging Methodische Weiterentwicklungen der konfokalen Scanning-Laser-Ophthalmoskopie.

BACKGROUND: Fundus autofluorescence (FAF) originates from age- and disease-dependent accumulation of lipofuscin in the lysosomal compartment of the retinal pigment epithelium (RPE). FAF imaging is a noninvasive method to detect intrinsic RPE fluorescence in vivo. We describe features of a novel confocal scanning laser ophthalmoscope (cSLO) for FAF imaging and compare images to the previous cSLO system. METHODS: FAF images were obtained with a cSLO using an optically pumped solid state laser (OPSL) instead of an argon laser for generation of excitation light at 488 nm. For detection of emitted FAF signals >500 nm a barrier filter was used. RESULTS: The novel cSLO allows FAF imaging with a resolution of up to 5 microm/pixel to delineate normal and pathological features in various retinal pathologies including early-stage and advanced atrophic or neovascular age-related macular degeneration, macular edema, and retinal dystrophies. Further technical improvements include an internal fixation target and an enlarged optical focus adaption range. CONCLUSIONS: Improved image quality using the novel cSLO for FAF imaging is of clinical relevance for diagnosis and precise phenotyping of retinal diseases. This method may also be useful to monitor therapeutic effects targeting RPE lipofuscin accumulation as a common pathogenetic pathway in various degenerative and hereditary retinal diseases.