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Dirofilariosis caused by Dirofilaria immitis (heartworm) is a zoonosis, considered an endemic disease of dogs and cats in several countries of Western Europe, including Portugal. This study assesses the levels of D. immitis exposure in humans from Northern Portugal, to which end, 668 inhabitants of several districts belonging to two different climate areas (Csa: Bragança, Vila Real and Csb: Aveiro, Braga, Porto, Viseu) were tested for anti-D. immitis and anti-Wolbachia surface proteins (WSP) antibodies. The overall prevalence of seropositivity to both anti-D. immitis and WSP antibodies was 6.1%, which demonstrated the risk of infection with D. immitis in humans living in Northern Portugal. This study, carried out in a Western European country, contributes to the characterisation of the risk of infection with D. immitis among human population in this region of the continent. From a One Health point of view, the results of the current work also support the close relationship between dogs and people as a risk factor for human infection
In Central America, population and food demands are rising rapidly, while yields of staple crops, maize and beans, remain low. To identify the main factors limiting production, field trials were established in six maize- and bean-producing regions in Guatemala, Honduras and El Salvador, representing about three-quarters of the maize-producing area. Potential yield-limiting factors were evaluated in 2017 and included: water stress, nutrient deficiency, pest and disease pressure, and/or inter-plant competition. When considering all sites, improved fertilization and pest and disease control significantly improved yields in maize by 11 and 16%, respectively but did not have a significant effect in beans. Irrigation had no effect due to good rainfall distribution over the growing season. Optimized planting arrangement resulted in an average 18% increase in maize yield, making it the most promising factor evaluated. The treatment and site combinations that increased both crop productivity and net profit included management changes that improved resource use efficiency. However, the contribution of each limiting factor to yield gaps varied across sites and no treatment was effective at increasing yield consistently across sites. Production constraints are highly dependent on local management practices and agroecological location. Therefore, public and private development efforts that seek to increase production should conduct multi-year, participatory experiments to identify limitations pertinent to the area in question. The next step is then to evaluate sustainable and profitable practices, to address those limitations and provide sound recommendations to farmers while decreasing the environmental and economic costs.
Heavy weight gilts commonly show signs of oestrus during the late finishing phase, which results in a period of reduced feed intake and growth rate. Immunization against gonadotropin-releasing hormone (GnRH) (IM, immunocastration) was developed for finishing boars and recently extrapolated to females. Immunocastration acts by suppressing reproductive activity and improving the growth potential. The objective of this study was to evaluate the effects of IM on growth performance, reproductive activity and carcass characteristics of late finishing gilts. Seventy-two gilts (63.49 ± 0.39 kg) were either injected with saline (Intact) or immunized against GnRH (Immunized). The study consisted of three experimental periods: between the first to second immunization (V1 to V2, 15 to 19 weeks of age), from the second immunization to the beginning of daily boar exposure (DBE) (V2 to DBE, 19 to 21 weeks of age) and from the beginning of DBE to slaughter (S) (DBE to S, 21 to 25 weeks of age). Immunized gilts showed an overall increase (from 15 to 25 weeks) of 3.90 kg (P < 0.05) of live weight, 56 g (P < 0.05) of average daily gain (ADG) and 250 g (P < 0.001) of average daily feed intake (ADFI). Immunized gilts had a greater ADFI (+240 g, P < 0.05) and worse feed conversion ratio (+0.26, P < 0.05) from 19 (V2) to 21 weeks of age (before DBE). Furthermore, those females had higher feed intake (+410 g; P < 0.001) plus greater daily weight gain (+92 g; P < 0.05) from V2 to S, and from DBE to S (+470 g of ADFI, P < 0.001; +129 g of ADG, P < 0.01, respectively). Immunocastration had no effect on backfat thickness, lean meat percentage and weight, cold carcass yield or loin depth (P > 0.05). Immunized gilts showed 4.4% increased cold carcass weight (P < 0.01) and 10.6% greater gross flank weight (P < 0.001). Immunization against GnRH did not influence shoulder, collar, loin, belly or ham weights. Nor did it influence belly fat thickness, or meat, skin plus fat and bones yields of cold ham (P > 0.05). Immunocastration reduced ovarian and uterine weights by 82% (P < 0.001) and 93% (P < 0.001), respectively, and suppressed oestrus manifestation in all gilts in the immunized group (P < 0.001). These results indicate that immunization against GnRH is a promising tool for stimulating growth performance with no detrimental effects on carcass quality of heavy weight finishing gilts, by means of oestrus suppression.
Smallholder livestock systems in Central America are typically based on pastures with traditional grasses and associated management practices, such as pasture burning and extensive grazing. With the rise of the global population and a corresponding increase in demand for meat and milk production, research efforts have focused on the development of improved grasses and the incorporation of legume species that can increase productivity and sustainability of Central American livestock systems. However, farmer adoption remains very limited, in part due to the lack of site-specific evaluation and recommendations by local institutions. Using a multi-site participatory approach, this study examined the potential of five improved grasses and five species of forage legumes as alternatives to the broadly disseminated grass Hyparrhenia rufa (cv. Jaragua) in pasture-based cattle systems in western Honduras and northern El Salvador. Improved grasses (four Brachiaria sp. and Megathyrsus maximus) produced significantly more biomass than H. rufa; also four of the five legume varieties evaluated (Canavalia ensiformis, Canavalia brasiliensis, Vigna unguiculata, and Vigna radiata) demonstrated high adaptability to diverse environmental conditions across sites. Farmer participatory evaluation offers a valuable means to assess performance of forages and will likely contribute to their improved utilization. Future research is needed on more refined management recommendations, pasture system design, costs and environmental benefits associated with the adoption of these forages in local livestock production systems.
Knowledge of tissue and cuts growth depending on the sex could be used to improve performance and efficiency. Computed tomography (CT) is a non-invasive technology that enables the study of the body composition of live animals during growth. The aims of the present study were (1) to evaluate variation in the body composition of four sex types (SEX) of pigs (castrated males (CM), immunocastrated males (IM), entire males (EM) and females (FE)) at the live weight of 30, 70, 100 and 120 kg, assessed using CT; (2) to model the growth of the main tissues and cuts; and (3) to predict the mature BW (MBW) of the four SEX and establish the relationships between the growth models and the MBW. There were significant phenotypic differences in the allometric growth of fat and lean among SEX. For the lean tissue, FE and EM showed higher values of the b coefficient than CM and IM (1.07 and 1.07 v. 1.00 and 1.02, respectively) all of them close to unity, indicating a proportional growth rate similar to live weight and that this tissue developed faster in FE and EM than in CM and IM. However, these differences were not related to differences in estimated MBW. There were significant differences in estimated MBW among SEX, being higher in IM and EM than in CM and FE (303 and 247 v. 219 and 216 kg), however, the MBW may have been overestimated, especially for the IM. The poorer accuracy of the MBW estimate for the IM could be due to a maximum live weight of 120 kg in the experiment, or to the fact that this particular SEX presented two clear behaviours, being more similar to EM from birth to the second injection of the vaccine (130 days) and comparable with CM from that point to the final BW.
We have combined observations of the Antennae galaxies from the radio interferometer ALMA and from the optical interferometer GHαFaS (Galaxy Hα Fabry-Perot System). The two sets of observations have comparable angular and spectral resolutions, enabling us to identify 142 giant molecular clouds (GMCs) and 303 Hii regions. We have measured, and compared, their basic physical properties (radius, velocity dispersion, luminosity). We study the mass functions of Hii regions and GMCs, where a double population of Hii regions due to a double population of GMCs is found. Using the velocity dispersion measurements, we claim that the difference between the regimes is the nature of the dominant binding force. For the regions in the lower mass range, the dominant force is the external pressure, while in the higher mass range it is the internal gravity of the clouds. We have applied the same method to similar observations (GHαFaS & ALMA) of Arp 236 and NGC 1614 finding similar results.
We have observed 3 pairs of interacting galaxies (the Antennae, Arp 236, and NGC 1614) using the Fabry-Perot interferometer GHαFaS (Galaxy Hα Fabry-Perot system) on the 4.2m William Herschel Telescope (WHT) at the Observatorio del Roque de los Muchachos, La Palma. We have extracted the physical properties (sizes, Hα luminosity and velocity dispersion) of Hii regions. We have combined also these observations with ALMA archival observations of these interacting galaxies, finding that there is a set of brighter and denser star forming regions. We have been able to compare these properties with those of two SMGs at redshift ~ 2.
Los Alamos National Laboratory has calculated a new generation of radiative opacities (OPLIB data using the ATOMIC code) for elements with atomic number Z = 1-30 with improved physics input, updated atomic data, and finer temperature grid to replace the Los Alamos LEDCOP opacities released in the year 2000. We calculate the evolution of standard solar models including these new opacities, and compare with models evolved using the Lawrence Livermore National Laboratory OPAL opacities (Iglesias & Rogers 1996). We use the solar abundance mixture of Asplund et al. 2009. The Los Alamos ATOMIC opacities (Colgan et al. 2013a, 2013b, 2015) have steeper opacity derivatives than those of OPAL for temperatures and densities of the solar interior radiative zone. We compare the calculated nonadiabatic solar oscillation frequencies and solar interior sound speed to observed frequencies and helioseismic inferences. The calculated sound-speed profiles are similar for models evolved using either the updated Iben evolution code (see Guzik & Mussack 2010), or the MESA evolution code (Paxton et al. 2015). The LANL ATOMIC opacities partially mitigate the ‘solar abundance problem’.
We present a new method for the detection and characterization of large scale expansion in galaxy discs based on Hα Fabry-Perot spectroscopy, taking advantage of the high spatial and velocity resolution of our instrument (GHαFaS). The method analyses multi-peaked emission line profiles to find expansion along the line of sight on a pixel-by-pixel basis. At this stage we have centred our attention on the large scale structures of expansive gas which show a coherent gradient of velocities from their centres as a result of both bubble shape and projection effect. The results show a wide range of expansion velocities in these superbubbles, ranging from 30-150 km/s, with the expected trend of finding the higher velocities in the more violent areas of the galaxies. We have applied the technique to the Antennae and M83, obtaining spectacular results, and used these to investigate to what extent kinematically derived ages can be found and used to characterize the ages of their massive star clusters.
Superbubbles and large scale expansion in galaxies are important indicators of activity in galaxies: they are formed in starbursts and around active nuclei. Superbubbles can be used to give information about the star-forming region which produced them. We present in-depth results of our study of kinematically detected superbubbles using a method based on Fabry-Perot spectroscopy, which allows us to map regions of expansion across the entire disk of a galaxy. Three objects have been selected for this poster based on the interest of the results they show: two interacting galaxies, the Antennae and Arp270, at different stages of galaxy interaction, and the more isolated galaxy M83. We present the kinematic expansion maps, as well as a census of detected superbubbles and a dynamical study of their properties.
We have observed 12 interacting galaxies using the Fabry-Perot interferometer GHαFaS (Galaxy Hα Fabry-Perot system) on the 4.2m William Herschel Telescope (La Palma). We have extracted the physical properties (sizes, Hα luminosity and velocity dispersion) of 236 HII regions for the full sample of interacting galaxies. We have derived the physical properties of 664 HII regions for a sample of 28 isolated galaxies observed with the same instrument in order to compare both populations of HII regions, finding that there are brighter and denser star forming regions in the interacting galaxies compared with the isolated galaxies sample.
Research carried out in several Anglo-Saxon countries shows that many undergraduates identify oral sex and anal sex as examples of abstinent behaviour, while many others consider kissing and masturbation as examples of having sex. The objective of this research was to investigate whether a sample of Spanish students gave similar replies. Seven hundred and fifty undergraduates (92% aged under 26, 67.6% women) produced examples or definitions of the term ‘abstinence’. Spanish students made similar errors to those observed in the Anglo-Saxon samples, in that behaviours that were abstinent from a preventive point of view (masturbating and sex without penetration) were not considered as such, while a number of students reported oral sex as abstinent behaviour. The results suggest that the information on risky and preventive sexual behaviour should cease to use ambiguous or euphemistic expressions and use vocabulary that is clear and comprehensible to everyone.
Multifunctional materials such as the single phase compound Pb(Fe0.5Nb0.5)O3 (PFN), where ferroelectric and antiferromagnetic order coexist, are very promising and have great interest from the academic and technological points of view. In this work, coupling of the ferroelectric and magnetic ordering has been observed. For this study, a combination of the small signal response using the impedance spectroscopy technique and the electromechanical resonance method with the large signal response through standard ferroelectric measurement, has been used with and without an applied magnetic field. The measurements to determine the electrical properties of the ceramic were performed as functions of the bias and poling electric fields. A simultaneous analysis of the complex dielectric constant , impedance , electric modulus , and the electromechanical coupling factors is presented. The results are correlated with a previous study of structural, morphological, small signal dielectric frequency-temperature response, and the ferroelectric hysteretic, magnetic and magnetodielectric behaviors. The observed shifts of the resonance and antiresonance frequency values can be associated with change of the domain size favored by the readjustment of the oxygen octahedron when the magnetic field is applied.From P-E hysteresis loops obtained without and with an external applied magnetic field a maximum value of dc magnetoelectric coefficient αME = 4 kV/cm T (400 mV/cm Oe) was obtained.
Fifteen nulliparous and nine multiparous Serrana goats were used, through two successive oestrous cycles, in order to characterize their ovulation time with regard to the number of ovulations after induced and natural oestrus during the breeding season. The onset of oestrus was detected by the amount of vasectomized bucks after oestrus synchronization with prostaglandin, given 10 days apart, and in the following two expected natural oestrus. The preovulatory LH peak was determined from blood samples collected 0, 4, 8, 12, 16, 20 and 24 h after onset of oestrus. A transrectal ovarian ultrasound scanning was performed 20, 24, 28, 32, 36, 40, 44 and 60 h after onset of oestrus, for the detection of ovulations by means of the disappearance of large follicles (>4 to 5 mm). Single ovulations were observed in 76% of oestrous periods in nulliparous goats and in 18% of nulliparous goats. The onset of oestrus to LH peak interval was lower in nulliparous (12.1 ± 0.9 h, n = 38) than in multiparous (15.6 ± 1.0 h, n = 22, P < 0.05) goats with no oestrus interaction effects (P > 0.05). The LH peak to first ovulation interval was higher after natural (18.9 ± 0.7 h, n = 36) than after induced (15.8 ± 1.2 h, n = 24, P < 0.05) oestrus. The onset of oestrus to total ovulation interval was influenced by parity (P < 0.01) and oestrus type (P < 0.05) with a length of 30.1 ± 1.1 h (n = 15) and 33.4 ± 1.5 h (n = 9) for induced oestrus of nulliparous and multiparous goats, respectively, and 32.5 ± 1.0 h (n = 23) and 36.5 ± 1.1 h (n = 13) for natural oestrus of nulliparous and multiparous goats, respectively. The onset of oestrus to first ovulation interval was not influenced by parity, but an interval of 8.0 ± 1.6 h was observed between the first and second ovulations in polyovulatory oestrus. Consequently, nulliparous goats that are predominantly monovular ovulate earlier than multiparous goats that are predominantly polyovulatory. In conclusion, significant differences occurred in the number and time of ovulations between nulliparous and multiparous goats. More research is necessary for a deeper understanding of the mechanisms regulating monovularory and polyovulatory oestrous cycles regarding the parity of goats.
The interaction between man-animal has a great impact on farm animal welfare and it constitutes an area of dynamic research. Typically the goal this kind of studies is to reach good management practices with lower costs and providing a better welfare to the animals. To evaluate the interaction man-animal many behavioural tests have been developed and applied to different animal species (Pajor et al., 2003; Lansade et al., 2004; Tallet et al., 2006). These tests are used to evaluate relationship between farm animals and their stockperson and how it affects the animal behaviour. The objective of this study is to compare the lamb behaviours of activity and vocalization of two breeds -Île-de-France (IF) and Churra da Terra Quente (CTQ) in a man-animal standard test.
Isotope ratios of elements such as Sr, Nd, Pb and Hf can be used as tracers of magmatic sources and processes. Analytical capabilities have evolved so that isotope ratios can now be analysed in situ, and isotopic tracers can therefore be used within single minerals to track the changing magmatic environment in which a given mineral grew. This contribution shows that Sr isotope ratios in feldspars that make up plutonic rocks will typically preserve initial isotopic variations, provided precise and accurate age corrections can be applied. Variations in initial isotope ratio can give a core-to-rim record of magmatic evolution and can be used to diagnose open system events such as contamination and magma recharge and mixing.
New single grain Sr isotope data are presented from the Dais Intrusion, Antarctica, which reflect an open system origin for the crystals. The crystal cargo appears to be aggregated and assembled during transport and emplacement. This model, as opposed to a magma body crystallising post emplacement, may be more applicable to plutonic rocks in general, and is testable using the in situ isotopic determination methods described here.
The most metal-poor stars provide important constraints on a number of problems, including the modeling of the early stages of galaxy assembly, the nature of first stars and the reionization. I present here numerical results on the distribution of metal-poor stars in stellar halos formed in a ΛCDM cosmology. I then discuss the results in light of current observational data of very metal-poor stars in the halos of Milky Way, Andromeda and neighboring dwarf galaxies.