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The BW has been largely used as a selection criterion in genetic selection programmes; however, increases in BW can affect animal metabolism and metabolites. The knowledge of how genetic potential for growth affects the metabolites can give a footprint of growth metabolism. This research aimed to evaluate the effect of genetic potential for post-weaning growth (GG) on performance, carcass traits and serum metabolome of non-castrated Nellore males during the finishing phase. Forty-eight Nellore non-castrated males, with divergent potential for post-weaning growth, were selected and divided into two groups: high potential for post-weaning growth (HG; n = 24) and low potential for post-weaning growth (LG; n = 24). Animals were kept and fed for 90 days where performance and ultrasound carcass traits were evaluated. Blood samples were collected at the beginning and end of feeding period to analyse serum metabolites concentration. The hot carcass weight and dressing percentage were recorded at slaughter. The feedlot performance and carcass traits were not affected by genetic potential. The HG animals had a lower glucose (P = 0.039), glutamate (P = 0.038), glutamine (P = 0.004), greater betaine (P = 0.039) and pyruvate (P = 0.039) compared to the LG group at the beginning of feedlot. In addition, higher creatine phosphate concentrations were observed at the beginning of feeding period, compared to final, for both groups (P = 0.039). In conclusion, the genetic potential for post-weaning growth does not affect performance and carcass traits during the finishing period. Differences in metabolite concentrations can be better found at the beginning of feedlot, providing a footprint of growth metabolism, but similar metabolite concentration at the end of finishing period.
Chagas disease (CD) is a neglected parasitic condition endemic in the Americas caused by Trypanosoma cruzi. Patients present an acute phase that may or not be symptomatic, followed by lifelong chronic stage, mostly indeterminate, or with cardiac and/or digestive progressive lesions. Benznidazole (BZ) and nifurtimox are the only drugs approved for treatment but not effective in the late chronic phase and many strains of the parasite are naturally resistant. New alternative therapy is required to address this serious public health issue. Repositioning and combination represent faster, and cheaper trial strategies encouraged for neglected diseases. The effect of imatinib (IMB), a tyrosine kinase inhibitor designed for use in neoplasias, was assessed in vitro on T. cruzi and mammalian host cells. In comparison with BZ, IMB was moderately active against different strains and forms of the parasite. The combination IMB + BZ in fixed-ratio proportions was additive. Novel 14 derivatives of IMB were screened and a 3,2-difluoro-2-phenylacetamide (3e) was as potent as BZ on T. cruzi but had low selectivity index. The results demonstrate the importance of phenotypic assays, encourage the improvement of IMB derivatives to reach selectivity and testify to the use of repurposing and combination in drug screening for CD.
Spineless cactus is a useful feed for various animal species in arid and semiarid regions due to its adaptability to dry and harsh soil, high efficiency of water use and carbohydrates storage. This meta-analysis was carried out to assess the effect of spineless cactus on animal performance, and develop and evaluate equations to predict dry matter intake (DMI) and average daily gain (ADG) in meat lambs. Equations for predicting DMI and ADG as a function of animal and diet characteristics were developed using data from eight experiments. The dataset was comprised of 40 treatment means from 289 meat lambs, in which cactus was included from 0 to 75% of the diet dry matter (DM). Accuracy and precision were evaluated by cross-validation using the mean square error of prediction (MSEP), which was decomposed into mean bias, systematic bias and random error; concordance correlation coefficient, which was decomposed into accuracy (Cb) and precision (ρ); and coefficient of determination (R2). In addition, the data set was used to evaluate the predicting accuracy and precision of the main lamb feeding systems (Agricultural and Food Research Council, Small Ruminant Nutritional System, National Research Council and Institut National de la Recherche Agronomique) and also two Brazilian studies. The DMI, CP intake (CPI), metabolizable energy (ME) intake and ADG increased when cactus was included up to 499 g/kg DM (P<0.001). In contrast, animals fed high levels of cactus (>500 g/kg DM) had a decreased DMI, CPI and NDF intake, but increased feed efficiency (P<0.001) and similar ADG compared with those without cactus addition. The DMI was positively correlated with initial BW, final BW, concentrate and ADG, while it was negatively correlated with cactus inclusion and ME of the diet. On other hand, ADG was positively correlated with DMI, initial and mean BW and concentrate, and it was negatively correlated with cactus inclusion. The two developed equations had high accuracy (Cb of 0.95 for DMI and 0.94 for ADG) and the random error of MSEP was 99% for both equations. The precision of both equations was moderate, with R2 values of 0.53 and 0.50 and ρ values of 0.73 and 0.71 for DMI and ADG, respectively. In conclusion, the developed equation to predict DMI had moderate precision and high accuracy, nonetheless, it was more efficient than those reported in the literature. The proposed equations can be a useful alternative to estimate intake and performance of lambs fed cactus.
Graded exercises tests are performed in adult populations; nonetheless, the use of this type of assessment is greatly understudied in overweight and obese adolescents.
To investigate heart rate autonomic responses to submaximal aerobic exercise in obese and overweight adolescents.
We recruited 40 adolescents divided into two groups: (1) overweight group comprising 10 boys and 10 girls between Z-score +1 and +2 and (2) obese group comprising 10 boys and 10 girls above Z-score >+2. Heart rate variability was analysed before (T1) and after exercise (T2–T4) on treadmill at a slope of 0%, with 70% of the maximal estimated heart rate (220 – age) for 20 minutes.
Heart rate in the overweight group was: 93.2±10.52 bpm versus 120.8±13.49 bpm versus 94.6±11.65 bpm versus 93.0±9.23 bpm, and in the obese group was: 92.0±15.41 bpm versus 117.6±16.31 bpm versus 92.1±12.9 bpm versus 91.8±14.33 bpm. High frequency in the overweight group was: 640±633.1 ms2 versus 84±174.66 ms2 versus 603.5±655.31 ms2 versus 762.6±807.21 ms2, and in the obese group was: 628.4±779.81 ms2 versus 65.4±119.34 ms2 versus 506.2±482.70 ms2 versus 677.9±939.05 ms2; and root mean square of successive differences in the overweight group was: 37.9±18.81 ms versus 10.9±8.41 ms versus 32.8±24.07 ms versus 36.7±21.86 ms, and in the obese group was: 38.7±23.17 ms versus 11.5±8.62 ms versus 32.3±16.74 ms versus 37.3±24.21 ms. These values significantly changed during exercise compared with resting values in overweight and obese groups. Moreover, we also reported no significant difference of resting parasympathetic control of heart rate between obese and overweight adolescents.
There was no significant difference of autonomic responses elicited by submaximal aerobic exercise between overweight and obese adolescents.
Three new species of the Neotropical genus Barbacenia (Velloziaceae, Pandanales) from Tocantins, Brazil, are described and illustrated, based on morphology and leaf anatomy. The known species richness of the genus is mapped within the countries of South America and the states of Brazil.
The increase of sheep meat competitiveness in international markets can be attributed to the rise of the quantity and the improvement of the quality of the edible portion of sheep carcasses. Usually, carcass yield is established after the slaughter of the animals. Yet, when carcass yield is determined in vivo, it can be both a costly and subjective method. This study proposes models for predicting the physical characteristics of lamb carcass using bioimpedance analysis (BIA) in live animals. Thirty-one Texel × Ile de France crossbreed ram lambs were slaughtered at 20, 26, 32 or 38 kg of BW. Before the slaughter, values of resistance (Rs) and reactance (Xc) were collected using a single-frequency BIA equipment (Model RJL Quantum II Bioelectrical Body Composition Analyzer). Then, BIA main variables such as body bioelectrical volume (V), phase angle (PA), resistive density (RsD) and reactive density (XcD) were calculated. After slaughter, cold carcass weight (CCW), cold carcass yield (CCY), subcutaneous fat thickness (SFT), soft tissue weight (STW) and soft tissue yield (STY) were also measured. Multiple regression analyses were carried out using the physical characteristics as dependent variables and the bioimpedance values as independent variables. Predictive performance of the models was assessed using leave-one-out cross-validation. The prediction model of CCW was obtained using the V, PA and RsD (R2 = 0.97), STW through the V, RsD and XcD (R2 = 0.97), CCY by Rs, Z and XcD (R2 = 0.69), STY by V and XcD (R2 = 0.67), and SFT only for XcD (R2 = 0.84). The results indicated that BIA has the potential to predict carcass characteristics of lambs at different body masses.
Phosphorus (P) is an essential nutrient in livestock production, involved in most metabolic processes in the body, and with an impact on bone development and growth. Diet supplementation with P can improve productivity, but at excess levels the P utilization can be low, and the high P excretion will lead to environmental pollution (Tamminga, 2003). P supplementation also adds substantially to the cost of feed. Using the isotopic dilution technique (Vitti et al., 2000), we have studied the effect of different P levels in diet on P absorption and excretion in Brazilian sheep, and identified the level at which true P absorption saturates.
In Northeast of Portugal sheep is reared under extensive systems. These systems frequently involve expressive body composition changes due to the storing and mobilization of body reserves, mainly fat. Body condition score (BCS) is the most common way to assess these reserves and the nutritional status of ewes. However due to the subjective nature of BCS, their quality has been questioned and other alternatives has been studied. For cattle there are some studies that use the real time ultrasonography (RTU) to evaluate the BCS (Schwager-Suter et al., 2000; Broring et al., 2003), but this approach was not tested in ewes. Therefore the aim of the present study was to establish a relationship between the BCS and ultrasound subcutaneous fat (SF) and Longissimus thoracis et lumborum muscle (LM) measurements.
Urban slums provide suitable conditions for infestation by rats, which harbour and shed a wide diversity of zoonotic pathogens including helminths. We aimed to identify risk factors associated with the probability and intensity of infection of helminths of the digestive tract in an urban slum population of Rattus norvegicus. Among 299 rats, eleven species/groups of helminths were identified, of which Strongyloides sp., Nippostrongylus brasiliensis and, the human pathogen, Angiostrongylus cantonensis were the most frequent (97, 41 and 39%, respectively). Sex interactions highlighted behavioural differences between males and females, as eg males were more likely to be infected with N. brasiliensis where rat signs were present, and males presented more intense infections of Strongyloides sp. Moreover, rats in poor body condition had higher intensities of N. brasiliensis. We describe a high global richness of parasites in R. norvegicus, including five species known to cause disease in humans. Among these, A. cantonensis was found in high prevalence and it was ubiquitous in the study area – knowledge which is of public health importance. A variety of environmental, demographic and body condition variables were associated with helminth species infection of rats, suggesting a comparable variety of risk factors for humans.
HR 6902 was the first target of a systematic study by Griffin (1986, JApA, 7, 195) of binaries showing composite spectra. It is also a well-studied member of the ζ Aur class. ζ Aur systems are long-period eclipsing binaries that are comprised of an evolved giant primary and a hot dwarf companion. Although those component stars have very different effective temperatures they have similar luminosities in the blue and near-UV regions, and hence display a composite spectrum at those wavelengths. In principle the ζ Aur systems are excellent tests of evolutionary and structural stellar models. In recent years the somewhat fragmentary eclipse photometry of HR 6902 has been out-classed by the high-precision continuous monitoring by the space mission CoRoT. HR 6902 was selected as a primary target of its seismology field, because the possible detection of solar-like pulsations in a giant component of a double-lined eclipsing binary could help to calibrate the scaling relation of giant pulsators. Our poster reported the results of a new analysis based on the CoRoT observations and follow-up spectroscopy with HARPS at the ESO 3.6-m telescope at La Silla.
The unprecedented accuracy of the CoRoT photometry enabled us to:
improve drastically the accuracy of the binary orbit and stellar parameters (by a factor ~10 for the radii)
extend the test of validity/calibration of the scaling relations to high stellar mass and radius, and put constraints on the evolutionary state (particularly since this binary is certainly free from tidal effects).
The scaling of turbulent motions is investigated by considering the flow in the eigenframe of the local strain-rate tensor. The flow patterns in this frame of reference are evaluated using existing direct numerical simulations of homogeneous isotropic turbulence over a Reynolds number range from
up to 1131, and also with reference to data for inhomogeneous, anisotropic wall turbulence. The average flow in the eigenframe reveals a shear layer structure containing tube-like vortices and a dissipation sheet, whose dimensions scale with the Kolmogorov length scale,
. The vorticity stretching motions scale with the Taylor length scale,
, while the flow outside the shear layer scales with the integral length scale,
. Furthermore, the spatial organization of the vortices and the dissipation sheet defines a characteristic small-scale structure. The overall size of this characteristic small-scale structure is
in all directions based on the coherence length of the vorticity. This is considerably larger than the typical size of individual vortices, and reflects the importance of spatial organization at the small scales. Comparing the overall size of the characteristic small-scale structure with the largest flow scales and the vorticity stretching motions on the scale of
shows that transitions in flow structure occur where
and 250. Below these respective transitional Reynolds numbers, the small-scale motions and the vorticity stretching motions are progressively less well developed. Scale interactions are examined by decomposing the average shear layer into a local flow, which is induced by the shear layer vorticity, and a non-local flow, which represents the environment of the characteristic small-scale structure. The non-local strain is
in width and height, which is consistent with observations in high Reynolds number flow of a
wide instantaneous shear layer with many
-scale vortical structures inside (Ishihara et al., Flow Turbul. Combust., vol. 91, 2013, pp. 895–929). In the average shear layer, vorticity aligns with the intermediate principal strain at small scales, while it aligns with the most stretching principal strain at larger scales, consistent with instantaneous turbulence. The length scale at which the alignment changes depends on the Reynolds number. When conditioning the flow in the eigenframe on extreme dissipation, the velocity is strongly affected over large distances. Moreover, the associated peak velocity remains Reynolds number dependent when normalized by the Kolmogorov velocity scale. It signifies that extreme dissipation is not simply a small-scale property, but is associated with large scales at the same time.
Several studies have shown that maternal low-protein (LP) diet induces detrimental effects in cardiovascular system and oxidative stress in male animals. Additional studies suggested that female has lower incidence of cardiovascular disease. However until present data, the possible effects of estradiol on the undernutrition during gestational and lactation periods are not discussed. The present study was conducted to evaluate the effects of a maternal LP diet during gestational and lactation period on oxidative balance in the female rat hearts ventricles at two ages. Dams were fed with normal protein (NP) or a LP diet during the gestational and lactation period, and their female offspring were divided into age groups (22 or 122 days, corresponding to a low or high estrogen level) composing four experimental groups. Evaluating the nutritional effect showed an increase in oxidative stress biomarkers and decrease in enzymatic defense in LP-22D compared with NP-22D. In contrast, no changes were observed in malondialdehyde and carbonyls, but an increase in glutathione-S-transferase (GST) activity in the LP-122D compared with NP-122D. The global oxy-score in the LP-22D group indicated a predominance of oxidative damage when compared with NP-22D, while in LP-122D group the global oxy-score was restored to NP-122D levels. Evaluating the estradiol effect, our data show a significant decrease in oxidative stress with increase in CAT and GST activity, associated with increase in intracellular thiols. Our data suggest that in situation with low levels of estradiol, hypoproteic diet during gestation and lactation period has detrimental effects on heart, however when estradiol levels raise, the detrimental effects induced are mitigated.
The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
Rhodnius prolixus is a blood-feeding insect that transmits Trypanosoma cruzi and Trypanosoma rangeli to vertebrate hosts. Rhodnius prolixus is also a classical model in insect physiology, and the recent availability of R. prolixus genome has opened new avenues on triatomine research. Glycogen synthase kinase 3 (GSK-3) is classically described as a key enzyme involved in glycogen metabolism, also acting as a downstream component of the Wnt pathway during embryogenesis. GSK-3 has been shown to be highly conserved among several organisms, mainly in the catalytic domain region. Meanwhile, the role of GSK-3 during R. prolixus embryogenesis or glycogen metabolism has not been investigated. Here we show that chemical inhibition of GSK-3 by alsterpaullone, an ATP-competitive inhibitor of GSK3, does not affect adult survival rate, though it alters oviposition and egg hatching. Specific GSK-3 gene silencing by dsRNA injection in adult females showed a similar phenotype. Furthermore, bright field and 4’−6-diamidino-2-phenylindole (DAPI) staining analysis revealed that ovaries and eggs from dsGSK-3 injected females exhibited specific morphological defects. We also demonstrate that glycogen content was inversely related to activity and transcription levels of GSK-3 during embryogenesis. Lastly, after GSK-3 knockdown, we observed changes in the expression of the Wingless (Wnt) downstream target β-catenin as well as in members of other pathways such as the receptor Notch. Taken together, our results show that GSK-3 regulation is essential for R. prolixus oogenesis and embryogenesis.
Infectious bovine keratoconjunctivitis (IBK) is a common and important disease of calves. Without effective vaccines, antibiotic therapy is often implemented to minimize the impact of IBK. This review updates a previously published systematic review regarding comparative efficacy for antibiotic treatments of IBK. Available years of Centre for Biosciences and Agriculture International and MEDLINE databases were searched, including non-English results. Also searched were the American Association of Bovine Practitioners and World Buiatrics Congress conference proceedings from 1996 to 2016, reviews since 2013, reference lists from relevant trials, and U.S. Food and Drug Administration New Animal Drug Application summaries. Eligible studies assessed antibiotic treatment of naturally-occurring IBK in calves randomly allocated to group at the individual level. Outcomes of interest were clinical score, healing time, unhealed ulcer risk, and ulcer surface area. A mixed-effects model comparing active drug with placebo was employed for all outcomes. Heterogeneity was assessed visually and using Cochran's Q-test. Thirteen trials assessing nine treatments were included. Compared with placebo, most antibiotic treatments were effective. There was evidence that the treatment effect differed by day of outcome measurement. Visually, the largest differences were observed 7–14 days post-treatment. These results indicate improved IBK healing with many antibiotics and suggest the need for randomized trials comparing different antibiotic treatments.
Late-type evolved stars are well known for the decrease with age of their rotation and lithium abundance. However, the root cause of this property as well as the relationship between rotation and lithium content in these stars are not yet completely established. In the present work, we study the link between rotation and lithium abundances in solar-type giant stars on the basis of a large sample of 380 stars of spectral type F, G and K.
The analysis of 72 binaries with component of luminosity class III shows that the behavior of Li abundance in such systems follows the same pattern presented by their single counterparts. Binarity seems to affect the lithium dilution in systems presenting orbital period lower than about 100 days.
Patients with a deletion at chromosome 22q11.2 (22q11DS) have 30% lifetime risk of developing a psychosis. People fulfilling clinical criteria for ultra-high risk (UHR) for psychosis have 30% risk of developing a psychosis within 2 years. Both high-risk groups show white-matter (WM) abnormalities in microstructure and volume compared to healthy controls (HC), which have been related to psychotic symptoms. Comparisons of WM pathology between these two groups may specify WM markers related to genetic and clinical risk factors.
Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) were assessed using diffusion tensor magnetic resonance imaging (MRI), and WM volume with structural MRI, in 23 UHR patients, 21 22q11DS patients, and 33 HC.
Compared to UHR patients 22q11DS patients had (1) lower AD and RD in corpus callosum (CC), cortical fasciculi, and anterior thalamic radiation (ATR), (2) higher FA in CC and ATR, and (3) lower occipital and superior temporal gyrus WM volume. Compared to HC, 22q11DS patients had (1) lower AD and RD throughout cortical fasciculi and (2) higher FA in ATR, CC and inferior fronto-occipital fasciculus. Compared to HC, UHR patients had (1) higher mean MD, RD, and AD in CC, ATR and cortical fasciculi, (2) no differences in FA.
UHR and 22q11DS patients share a susceptibility for developing psychosis yet were characterized by distinct patterns of WM alterations relative to HC. While UHR patients were typified by signs suggestive of aberrant myelination, 22q11DS subjects showed signs suggestive of lower axonal integrity.
La centralisation au Bureau international de l’Heure des résultats d’observations de l’Opération internationale de 1933 a été très lente, puisque les dernières données attendues ont été reçues vers la fin de 1937.
Le nombre des stations ayant coopéré à l’Opération internationale et ayant transmis leurs observations à l’organisme centralisateur s’élève à soixante et onze. Ainsi qu’il a été expliqué à notre Commission mixte, lors du Congrès de l’Union géodésique et géophysique internationale tenu à Édimbourg en 1936, ces stations ont été réparties en trois groupes:
Le Ier comprenant vingt Observatoires, disposant chacun de plusieurs horloges de première classe (soit à poids sous pression et à température constantes, soit à quartz piézoélectrique);