Nota corta. Análisis de heterogeneidad entre aislados de Mycoplasma pullorum por medio de técnicas de amplificación de DNA polimórfico

Mycoplasmas were isolated from chickens with respiratory problems during field investigations of a concentrated respiratory disease outbreak in western Cuba, 1997. A high percentage of mycoplasma cultures from tracheas and air-sac lesions yielded pure cultures of Mycoplasma pullorum. The aim of the present work was to investigate the heterogeneity among M. pullorum isolates from Cuba and strains from other countries using random amplified polymorphic DNA (RAPD) techniques. The results show that the RAPD method may be a useful identification tool for studying the epidemiology of poultry mycoplasmosis in Cuba.En 1997 se aislaron micoplasmas en el curso de investigaciones de campo en pollos con un brote de enfermedad respiratoria localizada en la zona oeste de Cuba. Un alto porcentaje de los cultivos de micoplasmas procedentes de lesiones de tráquea y alveolos revelaron la presencia de Mycoplasma pullorum. El objetivo de este trabajo fue investigar la heterogeneidad de los aislados cubanos entre sí y con cepas de otros países, mediante la técnica RAPD (DNA polimórfico amplificado al azar). Los resultados muestran que la técnica RAPD puede ser una herramienta de identificación útil en el estudio de la epidemiología de la micoplasmosis aviar en Cuba

Polymerase chain reaction-based discrimination of viable from non-viable <i>Mycoplasma gallisepticum</i>

The present study was based on the reverse transcription polymerase chain reaction (RT-PCR) of the 16S ribosomal nucleic acid (rRNA) of Mycoplasma for detection of viable Mycoplasma gallisepticum. To determine the stability of M. gallisepticum 16S rRNA in vitro, three inactivation methods were used and the suspensions were stored at different temperatures. The 16S rRNA of M. gallisepticum was detected up to approximately 20–25 h at 37 °C, 22–25 h at 16 °C, and 23–27 h at 4 °C. The test, therefore, could detect viable or recently dead M. gallisepticum (< 20 h). The RT-PCR method was applied during an in vivo study of drug efficacy under experimental conditions, where commercial broiler-breeder eggs were inoculated with M. gallisepticum into the yolk. Hatched chicks that had been inoculated in ovo were treated with Macrolide 1. The method was then applied in a flock of day 0 chicks with naturally acquired vertical transmission of M. gallisepticum, treated with Macrolide 2. Swabs of the respiratory tract were obtained for PCR and RT-PCR evaluations to determine the viability of M. gallisepticum. This study proved that the combination of both PCR and RT-PCR enables detection and differentiation of viable from non-viable M. gallisepticum

Age before beauty? Relationships between fertilization success and age-dependent ornaments in barn swallows

When males become more ornamented and reproduce more successfully as they grow older, phenotypic correlations between ornament exaggeration and reproductive success can be confounded with age effects in cross-sectional studies, and thus say relatively little about sexual selection on these traits. This is exemplified here in a correlative study of male fertilization success in a large colony of American barn swallows (Hirundo rustica erythrogaster). Previous studies of this species have indicated that two sexually dimorphic traits, tail length and ventral plumage coloration, are positively correlated with male fertilization success, and a mechanism of sexual selection by female choice has been invoked. However, these studies did not control for potential age-related variation in trait expression. Here, we show that male fertilization success was positively correlated with male tail length but not with plumage coloration. We also show that 1-year-old males had shorter tails and lower fertilization success than older males. This age effect accounted for much of the covariance between tail length and fertilization success. Still, there was a positive relationship between tail length and fertilization success among older males. But as this group consisted of males from different age classes, an age effect may be hidden in this relationship as well. Our data also revealed a longitudinal increase in both tail length and fertilization success for individual males. We argue that age-dependent ornament expression and reproductive performance in males complicate inferences about female preferences and sexual selection

Potential for increased connectivity between differentiated wolverine populations

Information on genetic population structure provides important knowledge for species conservation. Yet, few studies combine extensive genetic data to evaluate the structure and population dynamics of transboundary populations. Here we used single nucleotide polymorphisms (SNPs), microsatellites and mitochondrial haplotypes to analyze the genetic population structure of wolverines (Gulo gulo) across Fennoscandia using a long-term monitoring dataset of 1708 individuals. Clear population subdivision was detected between the Scandinavian and the eastern Finnish population with a steep cline in the contact zone. While the Scandinavian population showed isolation by distance, large swaths of this population were characterized by high connectivity. Areas with high resistance to gene flow are likely explained by a combination of factors, such as historical isolation and founder effects. From a conservation perspective, promoting gene flow from the population in eastern Finland to the northwest of Scandinavia could augment the less variable Scandinavian population, and increase the demographic resilience of all subpopulations. Overall, the large areas of low resistance to gene flow suggest that transboundary cooperation with aligned actions of harvest and conflict mitigation could improve genetic connectivity across Finland, Sweden, and Norway

Tax Enforcement in an Agent-Based Model with Endogenous Audits

We generalize the classic Allingham and Sandmo’s model of tax evasion considering heterogeneous agents with different degrees of tax morale and matchable, as opposed to non-matchable, income. The Tax Agency evolves its control scheme, maximizing the revenues from fines, and takes into account some minimal information on the taxpayers. We compare different audit policies and find that the most effective scheme remarkably depends on the way agents update the subjective probability of being audited, on the distribution of matchable income in the population as well as on the level of tax morale. Hence, different features of societies and taxpayers’ behaviors not only affect the compliance rate, as expected, but require the Tax Agency to alter its audit policy in a context-dependent way. In particular, high revenues are obtained performing random audits when agents think they are directed towards peculiar individuals and, conversely, should be biased towards low declarations when taxpayers believe audits are nonspecific or random

Surgery for degenerative rotator cuff tears: a health technology assessment

Source at https://www.fhi.no/.Vi har utarbeidet en fullstendig metodevurdering av kirurgi med sutur sammenlignet med ikke-kirurgisk behandling ved degenerativ fulltykkelse rotatorcuff-ruptur. Vi inkluderte fem randomiserte og 18 ikke-randomiserte studier. Vi sammenstilte studiene i metaanalyser og vurderte tilliten til effektestimatene med GRADE-tilnærmingen. For pasienter med ruptur i én sene gir kirurgi liten eller ingen klinisk relevant forskjell i smerte, nattesmerte, funksjon, pasienttilfredshet og helserelatert livskvalitet sammenlignet med ikke-kirurgisk behandling ved ett år (GRADE: middels til lav). For pasienter med ruptur i én eller to sener gir kirurgi litt høyere pasienttilfredshet, men liten eller ingen klinisk relevant forskjell i smerte, nattesmerte, funksjon og helserelatert livskvalitet sammenlignet med ikke-kirurgisk behandling ved ett år (GRADE: middels til lav). Re-ruptur / manglende tilheling forekom hos mellom 5 % og 35 % seks måneder til ti år etter kirurgi og økt rupturstørrelse hos 59 % etter ti år ved ikke-kirurgisk behandling (GRADE: ikke vurdert). Det ble rapportert få alvorlige uønskede hendelser, men kunnskapsgrunnlaget her er tynt og vi er usikre på absolutt risiko. Den helseøkonomiske hovedanalysen viste at kirurgi er det mest kostbare alternativet, med en kostnadsforskjell på ca 36 000 kroner og en forventet akkumulert forskjell i effekt over fem år på 0,09 QALYs. Dette gir en IKER på 389 035 kroner per QALY. • Potensielle årlige kostnadsbesparelser ved å velge kun ikke-kirurgisk behandling framfor kirurgi kan utgjøre inntil 81 millioner kroner. Estimatet er usikkert, og vil antakelig være noe lavere siden kirurgi vil være et behandlingsalternativ for enkelte pasienter. </uli

Sperm Length Variation as a Predictor of Extrapair Paternity in Passerine Birds

The rate of extrapair paternity is a commonly used index for the risk of sperm competition in birds, but paternity data exist for only a few percent of the approximately 10400 extant species. As paternity analyses require extensive field sampling and costly lab work, species coverage in this field will probably not improve much in the foreseeable future. Recent findings from passerine birds, which constitute the largest avian order (∼5,900 species), suggest that sperm phenotypes carry a signature of sperm competition. Here we examine how well standardized measures of sperm length variation can predict the rate of extrapair paternity in passerine birds.We collected sperm samples from 55 passerine species in Canada and Europe for which extrapair paternity rates were already available from either the same (n = 24) or a different (n = 31) study population. We measured the total length of individual spermatozoa and found that both the coefficient of between-male variation (CV(bm)) and within-male variation (CV(wm)) in sperm length were strong predictors of the rate of extrapair paternity, explaining as much as 65% and 58%, respectively, of the variation in extrapair paternity among species. However, only the CV(bm) predictor was independent of phylogeny, which implies that it can readily be converted into a currency of extrapair paternity without the need for phylogenetic correction.We propose the CV(bm) index as an alternative measure to extrapair paternity for passerine birds. Given the ease of sperm extraction from male birds in breeding condition, and a modest number of sampled males required for a robust estimate, this new index holds a great potential for mapping the risk of sperm competition across a wide range of passerine birds

Navigating the Murine Brain: Toward Best Practices for Determining and Documenting Neuroanatomical Locations in Experimental Studies

In experimental neuroscientific research, anatomical location is a key attribute of experimental observations and critical for interpretation of results, replication of findings, and comparison of data across studies. With steadily rising numbers of publications reporting basic experimental results, there is an increasing need for integration and synthesis of data. Since comparison of data relies on consistently defined anatomical locations, it is a major concern that practices and precision in the reporting of location of observations from different types of experimental studies seem to vary considerably. To elucidate and possibly meet this challenge, we have evaluated and compared current practices for interpreting and documenting the anatomical location of measurements acquired from murine brains with different experimental methods. Our observations show substantial differences in approach, interpretation and reproducibility of anatomical locations among reports of different categories of experimental research, and strongly indicate that ambiguous reports of anatomical location can be attributed to missing descriptions. Based on these findings, we suggest a set of minimum requirements for documentation of anatomical location in experimental murine brain research. We furthermore demonstrate how these requirements have been applied in the EU Human Brain Project to optimize workflows for integration of heterogeneous data in common reference atlases. We propose broad adoption of some straightforward steps for improving the precision of location metadata and thereby facilitating interpretation, reuse and integration of data