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Agents that block the renin–angiotensin system (RAS) improve glucoregulation in the metabolic syndrome disorder. We evaluated the effects of egg white hydrolysate (EWH), previously shown to modulate the protein abundance of RAS component in vivo, on glucose homeostasis in diet-induced insulin-resistant rats. Sprague–Dawley rats were fed a high-fat diet (HFD) for 6 weeks to induce insulin resistance. They were then randomly divided into four groups receiving HFD or HFD supplemented with different concentrations of EWH (1, 2 and 4 %) for another 6 weeks in the first trial. In the second trial, insulin-resistant rats were divided into two groups receiving only HFD or HFD+4 % EWH for 6 weeks. Glucose homeostasis was assessed by oral glucose tolerance and insulin tolerance tests. Insulin signalling and protein abundance of RAS components, gluconeogenesis enzymes and PPARγ were evaluated in muscle, fat and liver. Adipocyte morphology and inflammatory markers were evaluated. In vivo administration of EWH increased insulin sensitivity, improved oral glucose tolerance (P < 0·0001) and reduced systemic inflammation (P < 0·05). EWH potentiated insulin-induced Akt phosphorylation in muscle (P = 0·0341) and adipose tissue (P = 0·0276), but minimal differences in the protein abundance of tissue RAS components between the EWH and control groups were observed. EWH treatment also reduced adipocyte size (P = 0·0383) and increased PPARγ2 protein abundance (P = 0·0237). EWH treatment yielded positive effects on the inflammatory profile, glucose tolerance, insulin sensitivity and adipocyte differentiation in HFD-induced insulin resistance rats. The involvement of local RAS activity requires further investigation.
Non-decorticated sunflower meal (SFM) is a potential protein source for dairy cows with high-fibre content but high ruminal degradability. The effect of replacement of soybean meal (SBM) and wheat middlings (WM) with SFM on the intake, digestibility, microbial protein synthesis, nitrogen utilization and milk production of dairy cows was evaluated. Twelve Holstein cows were blocked by days in milk and distributed in three 4 × 4 Latin squares. Diets were formulated to be isonitrogenous and contained 550 g maize silage/kg dry matter (DM). Treatment diets were no SFM (CON) or 70, 140 and 210 g/kg DM of SFM replacing fixed mixture of SBM and WM (536 and 464 g/kg of the mixture, respectively). The inclusion of SFM in diet did not affect DM intake, but intake of rumen degradable protein increased linearly. Inclusion of SFM reduced or tended to reduce total-tract digestibility of non-fibre carbohydrate, total digestible nutrients and excretion of purine derivatives. Milk production, milk protein content and efficiency of nitrogen use for lactation were reduced with increasing levels of SFM in the diet. The use of non-decorticated SFM as a replacement for SBM–WM mixture in diet reduces performance and efficiency of nutrient use in lactating dairy cows. The outcome of the current study is attributed to reduced fibre digestibility in SFM hulls. Therefore, future studies should evaluate the use of decorticated SFM.
An experiment was conducted to evaluate whether dietary reduction and sex class affect nutrient intake, digestibility, purine derivative (PD) excretion and heat tolerance coefficient in lambs. Thirty-five hair lambs (14.5 ± 0.89 kg initial body weight (BW), 2 months old) were used in a completely randomized study with a 3 × 3 factorial arrangement, three sex classes (11 intact males, 12 castrated males and 12 females) and three levels of feeding (ad libitum, 300 and 600 g/kg/dry matter (DM) feed restriction) for 120 days. Intact and castrated males showed higher intakes of DM and neutral detergent fibre corrected for ash and protein (NDFap) than females. At 300 g/kg/DM feed restriction, NDFap digestibility was lower in intact males than in other classes; however, no differences were found between classes when subjected to ad libitum feeding or 600 g/kg/DM. The basal endogenous nitrogen and endogenous urinary losses were highest in intact males. Allantoin, uric acid and PD excretion, as well as PD absorption and microbial protein production were lowest in the animals subjected to 600 g/kg/DM feed restriction. Microbial protein synthesis (MPS) was highest in animals subjected to 600 g/kg/DM feed restriction. The lowest temperatures were observed in animals subjected to 600 g/kg/DM feed restriction. The heat tolerance coefficient was highest in animals subjected to 600 g/kg/DM feed restriction. In conclusion, feed restriction reduced the time spent on feeding and rumination but increased the digestibility of DM. The restriction level of 600 g/kg/DM maximized MPS and infrared thermography indicated an elevated heat tolerance coefficient.
The objective of the current study was to evaluate the effects of sugarcane and maize silage mixture v. maize silage in diets of Holstein cows and investigate performance under two environmental conditions. The cows were placed in freestalls, with individuals and stalls assigned to one of four treatments according to a replicated 4 × 4 Latin square design with 20-day periods divided into 11 days of adaptation (wash-out period) and 9 days of collection. Treatments were arranged in a 2 × 2 × 2 factorial design: total diets (maize silage (MS-based diet), the roughage mixture (RM-based diet, sugarcane : maize silage, 500 : 500 g/kg DM) plus concentrate); environmental conditions (with (W) and without (Wo) fan and nebulizers); and measurement times (09.40 and 14.00 h). The temperature and relative humidity was higher at 14.00 h and contributed to increased temperature-humidity index (76.6, W v. 75.9, Wo). Feed dry matter intake (DMI) was similar between diets (20.2 kg/day), but milk production and feed efficiency were lower with RM. Under W conditions, higher fat content and total solids of milk were observed with the RM-based diet, while crude protein and lactose were higher with MS. The Wo conditions increased body surface temperature (BS) in cows fed MS. The rectal temperature (RT) was higher with RM. The BS, RT and respiratory rate were higher at 14.00 h (34.9, 38.6 °C and 58.2 breaths/min) than at 09.40 h. The RM-based diet maintained DMI and milk composition, but not milk production. The use of the cooling system led to higher DMI and feed N efficiency use.
The aim of this study was to establish a functional freezing–thawing protocol for epididymal sperm of collared peccaries (Pecari tajacu L., 1758) by comparing different extenders. The epididymal sperm from 12 sexually mature males was recovered by retrograde flushing using Tris-based or coconut water-based (ACP®-116c) extenders. After initial evaluation, samples were diluted and frozen with the same extenders to which 20% egg yolk and 6% glycerol were added. After 2 weeks, thawing was performed at 37°C/60 s and sperm motility, vigour, morphology, functional membrane integrity, sperm viability, sperm plasma membrane integrity, and a computer-assisted semen analysis (CASA) were assessed. In addition, to evaluate the survival of frozen–thawed sperm, a thermal resistance test (TRT) was executed. Samples preserved using Tris were in better condition compared with those preserved using ACP®, showing higher values for most assessments performed, including CASA and the TRT (P<0.05). After determining Tris to be the better of the two extenders, additional samples were thawed using different thawing rates (37°C/60 s, 55°C/7 s, 70°C/8 s). Sperm thawed at 37°C/60 s had the greatest preservation (P<0.05) of viability (54.1 ± 5.9%) and functional membrane integrity (43.2 ± 5.4%), and had higher values for various CASA parameters. In conclusion, we suggest the use of a Tris-based extender added to egg yolk and glycerol for the cryopreservation of epididymal sperm obtained from collared peccaries. In order to achieve better post-thawing sperm quality, we suggest that samples should be thawed at 37°C/60 s.
Minerals are limiting factors in animal production, and the knowledge of mineral requirements for livestock is crucial to the success of a commercial enterprise. Hair sheep may have different mineral requirements than those presents by the international committees. A study was carried to evaluate the net calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) requirements for the growth and maintenance of Brazilian Somali lambs. A total of 48 hair lambs (13.5±1.8 kg) aged 60±15 days were allocated to individual pens. Eight animals were slaughtered at the beginning of the experiment to serve as a reference group to estimate initial empty BW (EBW) and initial body composition. The remaining lambs (n=40) were assigned to a completely randomized design with eight replications in five levels of metabolizable energy (ME; 4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg DM). When the lambs of a given treatment reached an average BW of 28 kg, they were slaughtered. Initial body composition was used to calculate the retention of minerals. Mineral body composition was fit using a logarithmic equation in the form of a nonlinear model. The maintenance requirements were estimated from regressions of mineral retention in the empty body on mineral intake. The body mineral concentration decreased in lambs with a BW ranging from 15 to 30 kg. The net mineral requirements (100 g/day of average daily gain (ADG)) decreased from 0.52 to 0.51 g for Ca, 0.28 to 0.23 g for P, 0.02 to 0.02 g for Mg, 0.09 to 0.08 g for Na, 0.11 to 0.09 g for K, 1.30 to 1.08 mg for Zn, 3.77 to 3.22 mg for Fe, 0.08 to 0.06 mg for Mn and 0.09 to 0.08 mg for Cu when BW increased from 15 to 30 kg. The daily net requirements for maintenance per kilogram of BW were 30.13 mg of Ca, 27.58 mg of P, 1.26 mg of Mg, 4.12 mg of Na, 8.11 mg of K, 0.133 mg of Zn, 0.271 mg of Fe, 0.002 mg of Mn and 0.014 mg of Cu. The results of this study indicate that the net mineral requirements for weight gain and maintenance in Brazilian Somali lambs are different than the values that are commonly recommended by the main evaluation systems for feed and nutritional requirements for sheep. These results for the nutritional requirements of minerals may help to optimize mineral supply for hair sheep.
Nitrate (NO3−) is an ergogenic nutritional supplement that is widely used to improve physical performance. However, the effectiveness of NO3− supplementation has not been systematically investigated in individuals with different physical fitness levels. The present study analysed whether different fitness levels (non-athletes v. athletes or classification of performance levels), duration of the test used to measure performance (short v. long duration) and the test protocol (time trials v. open-ended tests v. graded-exercise tests) influence the effects of NO3− supplementation on performance. This systematic review and meta-analysis was conducted and reported according to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. A systematic search of electronic databases, including PubMed, Web of Science, SPORTDiscus and ProQuest, was performed in August 2017. On the basis of the search and inclusion criteria, fifty-four and fifty-three placebo-controlled studies evaluating the effects of NO3− supplementation on performance in humans were included in the systematic review and meta-analysis, respectively. NO3− supplementation was ergogenic in non-athletes (mean effect size (ES) 0·25; 95 % CI 0·11, 0·38), particularly in evaluations of performance using long-duration open-ended tests (ES 0·47; 95 % CI 0·23, 0·71). In contrast, NO3− supplementation did not enhance the performance of athletes (ES 0·04; 95 % CI −0·05, 0·15). After objectively classifying the participants into different performance levels, the frequency of trials showing ergogenic effects in individuals classified at lower levels was higher than that in individuals classified at higher levels. Thus, the present study indicates that dietary NO3− supplementation improves physical performance in non-athletes, particularly during long-duration open-ended tests.
Invasive group A streptococcal (iGAS) infections cause severe disease and death, especially in residents of long-term care facilities (LTCFs). In order to inform iGAS prevention, we compared the risk of iGAS in LTCF residents and community residents. We identified LTCF residents among cases of iGAS from national surveillance (2009–2010) using postcode matching, and cases of hospital-acquired infections via hospital admission records. We used Poisson regression to calculate incidence rate ratios (IRR) and logistic regression to explore factors associated with case fatality rate (CFR). A total of 2741 laboratory-confirmed iGAS cases were matched to a hospital admission: 156 (6%) were defined as hospital-acquired. Out of the total cases, 96 (3·5%) were LTCF residents. Compared with community residents, LTCF residents over 75 years of age had a higher risk of iGAS infection (IRR = 1·7; 95% CI 1·3–2·1) and CFR (OR = 2·3; 95% CI 1·3–3·8). Amongst community-acquired cases, the risk of iGAS in LTCF residents between 75 and 84 years of age doubled (IRR = 2·7; 95% CI 1·8–3·9) compared with their community counterparts. The CFR among community-acquired cases was higher in LTCF residents than community residents (21% vs. 11%). Age remained associated with death in our final model. Our study showed that, even controlling for age, LTCF residents have a higher risk of acquiring and dying from iGAS. Whilst existing co-morbidities may explain this, it is reasonable to assume that the institutional setting may facilitate transmission. Therefore, cases in LTCF require prompt investigation together with a better understanding of factors contributing to the acquisition of infection.
Ureaplasma urealyticum and U. parvum have been associated with genital infections. The purpose of this study was to detect the presence of ureaplasmas and other sexually transmitted infections in sexually active women from Brazil and relate these data to demographic and sexual health, and cytokines IL-6 and IL-1β. Samples of cervical swab of 302 women were examined at the Family Health Units in Vitória da Conquista. The frequency of detection by conventional PCR was 76·2% for Mollicutes. In qPCR, the frequency found was 16·6% for U. urealyticum and 60·6% U. parvum and the bacterial load of these microorganisms was not significantly associated with signs and symptoms of genital infection. The frequency found for Trichomonas vaginalis, Neisseria gonorrhoeae, Gardnerella vaginalis and Chlamydia trachomatis was 3·0%, 21·5%, 42·4% and 1·7%, respectively. Higher levels of IL-1β were associated with control women colonized by U. urealyticum and U. parvum. Increased levels of IL-6 were associated with women who exhibited U. parvum. Sexually active women, with more than one sexual partner in the last 3 months, living in a rural area were associated with increased odds of certain U. parvum serovar infection.
An experiment was carried to evaluate the energy and protein requirements for the growth and maintenance of lambs of different sex classes. In all, 38 hair lambs (13.0±1.49 kg initial BW and 2 months old) were allocated in a factorial design with diet restriction levels (ad libitum, 30% and 60% feed restriction) and sex classes (castrated and non-castrated males). Four animals from each sex class were slaughtered at the beginning of the trial as a reference group to estimate the initial empty BW and body composition. The remaining lambs were weighed weekly to calculate BW gain (BWG), and when the animals fed ad libitum reached an average BW of 30 kg, all of the experimental animals were slaughtered. Before slaughter, fasted BW (FBW) was determined after 18 h without feed and water. Feed restriction induced reductions in body fat and energy concentration, whereas water restriction showed the opposite effect, and the protein concentration was not affected. The increase in BW promoted increases in body fat and energy content, and these increases were greater in castrated lambs, whereas the protein content was similar between classes tending to stabilize. The net energy required for gain (NEg) and the net protein required for gain (NPg) were not affected by sex class; therefore, an equation was generated for the combined results of both castrated and non-castrated lambs. The NEg varied from 1.13 to 2.01 MJ/day for lambs with BW of 15 and 30 kg and BWG of 200 g. The NPg varied from 24.57 to 16.33 g/day for lambs with BW of 15 and 30 kg and BWG of 200 g. The metabolizable energy efficiency for gain (kg) was 0.37, and the metabolizable protein efficiency for gain (kpg) was 0.28. The net energy required for maintenance (NEm) and the net requirement of protein for maintenance (NPm) did not differ between castrated and non-castrated lambs, with values of 0.241 MJ/kg FBW0.75 per day and 1.30 g/kg FBW0.75 per day, respectively. The metabolizable energy efficiency for maintenance (km) was 0.60, and the efficiency of metabolizable protein use for maintenance (kpm) was 0.57. Nutritional requirements for growth and maintenance did not differ between castrated and non-castrated lambs. This study emphasizes the importance of updating the tables of international committees and of including data obtained from studies with sheep breeds raised in tropical conditions, with the purpose of improving the productive efficiency of the animals
Pertussis is a worldwide acute respiratory disease caused by the bacterium Bordetella pertussis. Despite high vaccine coverage, the bacterium continues to circulate in populations and is still one of the most common vaccine-preventable diseases. In Brazil, pertussis incidence has presented a significant decrease since 1990 but since 2011 a sudden increase in incidence has been observed. Thus, the aim of this study was to perform a molecular epidemiological characterization of B. pertussis strains isolated in the Central-Western region (specifically in Distrito Federal) of Brazil from August 2012 to August 2014. During this period, 92 B. pertussis strains were isolated from the outbreaks. All strains were characterized by serotyping and XbaI pulsed-field gel electrophoresis profiles. From August to December 2012, the most prevalent serotype observed was 1,3 (13/17). During 2013 the prevalence of serotype 1,3 decreased (13/30) and from January 2014 to August 2014 the most prevalent serotype was 1,2 (33/45). Fourteen PFGE profiles were identified. Of these, BP-XbaI0039 prevalence increased from 3/17 in 2012 to 10/30 in 2013, and 35/45 in 2014. These results evidence the selection of a specific genetic profile during this period, suggesting the occurrence of a bacterial genomic profile with high circulation potential.
The effect of heavy metal in fish has been the focus of extensive research for many years. However, the combined effect of heavy metals and nanomaterials is still a new subject that needs to be studied. The aim of this study was to examine histopathologic alterations in the gills of Nile tilapia (Oreochromis niloticus) to determine possible effects of lead (Pb), carbon nanotubes, and Pb+carbon nanotubes on their histological integrity, and if this biological system can be used as a tool for evaluating water quality in monitoring programs. For this, tilapia were exposed to Pb, carbon nanotubes and Pb+carbon nanotubes for 4 days. The main alterations observed were epithelial structure, hyperplasia and displacement of epithelial cells, and alterations of the structure and occurrence of aneurysms in the secondary lamella. The most severe alterations were related to the Pb+carbon nanotubes. We conclude that the oxidized multi-walled carbon nanotubes enhanced the acute lead toxicity in Nile tilapias. This work draws attention to the implications of carbon nanomaterials released in the aquatic environment and their interaction with classical pollutants.
The aim of this study was to evaluate the effect of nerolidol free (N-F) and nerolidol-loaded in nanospheres (N-NS) on the hepatic antioxidant/oxidant status of mice experimentally infected by Trypanosoma evansi. In the liver it was measured: reactive oxygen species (ROS), thiobarbituric reactive acid substances (TBARS) and non-protein thiols (NPSH), catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) and performed histopathological examination. In addition, seric levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Liver samples from mice infected by T. evansi showed increased (P < 0·05) ROS, TBARS, AST and ALT levels and SOD activity, and decreased NPSH levels and CAT activity (P < 0·05) compared with uninfected animals. N-NS treatment prevented (P < 0·05) ROS and TBARS increase, and increased NPSH levels, and ameliorate CAT and SOD activities on liver of infected mice. Moreover, N-NS treatment reduced (P < 0·05) AST and ALT levels, and prevented histopathological changes caused by the parasite. N-NS protected the liver from the oxidative stress caused by T. evansi, which might be due to its antioxidant properties. Nerolidol might be considered a promising therapeutic agent against oxidative stress, and nanotechnology is an encouraging approach to be explored.
Small-scale kG strong magnetic field elements in the solar photosphere are often identified as so-called magnetic bright points (MBPs). In principle these MBPs represent the cross-section of a vertical, strong, magnetic flux tube which is expanding with height in the solar atmosphere. As these magnetic elements represent possible MHD wave guides, a significant interest has been already paid to them from the viewpoint of observations and simulations. In this work we would like to shed more light on a possible scenario for the creation of such strong magnetic field concentrations. The accepted standard scenario involves the convective collapse process. In this ongoing work we will show indications that this convective collapse process may become triggered by sufficiently strong pressure disturbances. However, it is highly unlikely that p-mode waves can be of such a strength.
After 22 yr of the low-level liquid scintillation counting 14C laboratory at the Center for Nuclear Energy in Agriculture (CENA) at São Paulo University (USP), Piracicaba, Brazil, and several collaborative projects with Brazilian and international researchers from distinct scientific areas, the first 14C accelerator mass spectrometry (AMS) laboratory in Latin America was installed at the Physics Institute of the Universidade Federal Fluminense (UFF), Niterói, Brazil. A 250kV single stage accelerator produced by National Electrostatics Corporation began its operation in 2012. In this work, we compare measurements performed at the AMS Radiocarbon Laboratory at UFF (LAC-UFF) with those performed at CENA and the University of Georgia (UGAMS), Georgia, USA. All the results obtained from distinct inorganic and organic samples were in very good agreement.
Among several potential animal models that can be used for adipogenic studies, Wagyu cattle is the one that presents unique molecular mechanisms underlying the deposit of substantial amounts of intramuscular fat. As such, this review is focused on current knowledge of such mechanisms related to adipose tissue deposition using Wagyu cattle as model. So abundant is the lipid accumulation in the skeletal muscles of these animals that in many cases, the muscle cross-sectional area appears more white (adipose tissue) than red (muscle fibers). This enhanced marbling accumulation is morphologically similar to that seen in numerous skeletal muscle dysfunctions, disease states and myopathies; this might indicate cross-similar mechanisms between such dysfunctions and fat deposition in Wagyu breed. Animal models can be used not only for a better understanding of fat deposition in livestock, but also as models to an increased comprehension on molecular mechanisms behind human conditions. This revision underlies some of the complex molecular processes of fat deposition in animals.
The activity and circulation of influenza viruses in Argentina was studied during 2012 as part of the Argentinean Surveillance for Influenza and other Respiratory Viruses, in the context of Global Influenza Surveillance. The antigenicity and molecular characteristics of haemagglutinins (HA) of circulating influenza A and B viruses were analysed to assess the emergence of virus variants. Susceptibility to oseltamivir and zanamivir was evaluated by enzymatic assay and results were backed-up by sequencing of the neuraminidase (NA) genes. During the 2012 season, influenza virus circulation in Argentina was detected from weeks 24 to 51. The HA sequences of the studied A(H1N1)pdm09 subtype viruses segregated in a different genetic group compared to those identified during the 2009 pandemic, although they were still closely related antigenically to the vaccine virus A/California/07/2009. The HA sequences of the A(H3N2) viruses analysed fell into the A/Victoria/208/2009 clade, genetic group 3C. A mixed circulation of virus variants belonging to B/Victoria and B/Yamagata lineages was detected, with B/Victoria being dominant. All viruses tested were sensitive to oseltamivir and zanamivir except one. This isolate, an A(H1N1)pdm09 virus possessing the substitution NA-N295S, showed highly reduced inhibition by oseltamivir and reduced inhibition by zanamivir. Virological and epidemiological surveillance remains critical for detection of evolving influenza viruses.