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Heat stress due to increasing extremes in ambient temperature and humidity results in reduced semen quality in boars. This has caused reduced efficiency of the swine industry, requiring more boars to breed the same number of sows. Vitamins such as vitamin C (VC) and E (VE) have been shown to improve semen quality in boars. Recently, vitamin D has been shown to improve semen quality in boars. The purpose of this experiment was to evaluate the effects of increased supplemental vitamins on boar reproduction during the summer season in a commercial boar stud. One hundred and sixty Pig Improvement Company (PIC) terminal line boars (n = 32 per treatment) and 39 maternal, heat-sensitive boars (n = 7 or 8 per treatment) were randomly allocated to treatment and fed a corn and soybean meal-based diet adjusted based on individual boar body condition score. A control (CNT) diet was used that met PIC recommendations for boars. Increased supplementation of specific vitamins was given in the form of a top-dress and consisted of CNT wheat middlings, CNT plus VC (560 mg/day), CNT plus 25-hydroxy vitamin D3 (VD) (125 µg/day), CNT plus VE (275 mg/day) and CNT plus VC, VD and VE (CDE). The experiment was split into three periods based on maximum daily high temperatures in the barn, where period 1 was weeks 1 to 4, period 2 was weeks 5 to 11 and period 3 was weeks 12 to 14. Semen was collected from boars as needed using the stud’s normal production schedule and was analyzed for sperm quantity and quality characteristics. There were no dietary effects on semen volume, sperm concentration or total sperm production (P ≥ 0.553). Total motility of sperm was not impacted by diet (P = 0.115); although, VC tended (P = 0.064) to have a greater progressive motility than CDE. Percentages of morphologically normal sperm and normal acrosomes were not affected by dietary supplementation (P ≥ 0.157). Period effects were observed for most semen quality parameters, with quality generally becoming reduced over time. The present study demonstrates that increased supplementation of vitamins beyond PIC recommendations was not beneficial for boar reproduction during the summer.
The rate of deforestation in the Amazon is increasing. Predictive models estimate that as a result of agricultural expansion 40% of these forests will be lost by 2050. As a consequence the habitat of forest-dwelling species such as the Endangered black-faced black spider monkey Ateles chamek is being lost, particularly along the arc of deforestation in the Brazilian Amazon. We used species distribution modelling to (1) define the distribution of this spider monkey, using environmental predictors, (2) calculate the area of this distribution covered by the protected area network, and (3) calculate the expected loss of the species’ habitat under future scenarios of deforestation. We found that the species occupies only c. 28% of its extent of occurrence. Only 32% of the species’ area of occupancy is legally protected, and the modelling suggests that 31–40% of the species’ habitat will be lost by 2050. We highlight three unprotected regions with extensive forest cover that are predicted to become severely deforested by 2050 as priority regions for expanding the protected area network. We also propose landscape management and restoration in three human-modified regions. Our study provides an example of how species distribution modelling can be applied to assess threats to species and support decision makers in implementing conservation actions.
There have been few studies realized that evaluate the effects of adopting
different nutritional systems in more than one phase of cattle production on
carcass and meat characteristics. This study was realized to evaluate carcass
and meat characteristics from bulls submitted to different nutritional systems
during two production phases. The experiment was conducted at
Figueira’s farm during two production phases: I (cow–calf)
– 80 calves (99.6±2.72 days of age and
109.7±2.99 kg of BW) with their mothers were randomly assigned into
two supplemental diets: cow–calf mineral supplement
(n=40) or cow–calf creep-feeding
(n=40); II (stocker) – the same 80
calves (201.2±2.11 days of age and 190.2±3.37 kg of BW)
were redistributed into two production systems: stocker pasture
(n=40) or stocker feedlot (SF;
n=40). After, all 80 animals were kept on a pasture
system (III) for 290 days, and then finished in a feedlot system (IV) for more
33 days. Then, they were slaughtered at an average 764.2±3.06 days of
age and at 499.2±3.33 kg of final BW. After slaughter, the average
daily gain was calculated, and the carcass and meat characteristics were
measured. The statistical model design used was completely randomized in a
2×2 factorial arrangement (two treatment groups on
cow–calf phase and two treatment groups on stocker phase). The single
effects between the groups in each phase and the interactions between both
phases (cow–calf v. stocker) were analyzed. The
results were compared by Fisher’s test, using the R statistical
software. A cow–calf by stocker phases interaction occurred for
carcass conformation and fiber diameter. For single effects, the greatest
influences observed were in the stocker phase. The feedlot group was slaughtered
17 days earlier, with greater final BW (3.8%), hot carcass weight
(5.7%), average daily gain (6.9%), dressing percentage
(1.8%), carcass length (1.8%), carcass width
(1.5%), longissimus muscle area (4.8%)
and muscle depth (2.3%) than pasture group. The SF group also had
influence on fat color; showing higher L* and lower
b* values. These results reveal that bulls
reared in feedlot at the stocker phase have higher muscle development and that
the stocker phase has the greatest potential to influence carcass
characteristics and meat quality.
Due to the lack of basic information on water required by maize (Zea mays L.) in Brazil, the large amount of water applied usually exceeds crop requirements, wasting water and energy. In this study, we measured crop evapotranspiration (ETc) as evaporative heat flux from a centre pivot-irrigated maize plantation in Southern Brazil during winter and summer seasons, using the Bowen ratio method to evaluate how the degree of canopy-atmosphere coupling affects crop water needs and irrigation management. Irrigation requirements were determined by comparing ETc with reference evapotranspiration (ETo), derived from the Penman–Monteith equation and expressed as the ETc/ETo (Kc) ratio. In this study, the average Kc values obtained were 1.31 and 0.90 for the winter and summer, respectively. Using aerodynamic and canopy resistance measurements, the decoupling factor (Ω) was computed. Ω values tending to zero (0.09 and 0.20 for winter and summer, respectively) showed that strong coupling of maize plants to the atmosphere and sensitivity to high air temperatures, vapour pressure deficits and wind speed caused variations in Kc in relation to ETo ranges. During the experimental period, the Kc value ranged from 0.92 when the ETo exceeded 4 mm d−1 to 1.64 when the ETo was less than 2 mm d−1.
High concentrations of indium (In) and selenium (Se) have been reported in the Neves-Corvo volcanic-hosted massive sulfide deposit, Portugal. The distribution of these ore metals in the deposit is complex as a result of the combined effects of early ore-forming processes and late tectonometamorphic remobilization. The In and Se contents are higher in Cu-rich ore types, and lower in Zn-rich ore types. At the deposit scale, both In and Se correlate positively with Cu, whereas their correlations with Zn are close to zero. This argues for a genetic connection between Cu, In and Se in terms of metal sourcing and precipitation. However, re-distribution and re-concentration of In and Se associated with tectonometamorphic deformation are also processes of major importance for the actual distribution of these metals throughout the whole deposit. Although minor roquesite and other In-bearing phases were recognized, it is clear that most In within the deposit is found incorporated within sphalerite and chalcopyrite. When chalcopyrite and sphalerite coexist, the In content in sphalerite (avg. 1400 ppm) is, on average, 2–3 times higher than in chalcopyrite (avg. 660 ppm). The In content in stannite (avg. 1.3 wt.%) is even higher than in sphalerite, but the overall abundance of stannite is subordinate to either sphalerite or chalcopyrite. Selenium is dispersed widely between many different ore minerals, but galena is the main Se-carrier. On average, the Se content in galena is ~50 times greater than in either chalcopyrite (avg. 610 ppm) or sphalerite (avg. 590 ppm). The copper concentrate produced at Neves-Corvo contains very significant In (+Se) content, well above economic values if the copper smelters recovered it. Moreover, the high In content of sphalerite from some Cu-Zn ores, or associated with shear structures, could possibly justify, in the future, a selective exploitation strategy for the production of an In-rich zinc concentrate.
The in situ technique (NB) was compared to the in vitro gas production technique (Gas) in terms of ability to estimate the dry matter degradation (DMD) using high soluble substrates (maize grains) and low soluble substrates (four tropical forages). The experiments (in situ and in vitro) were carried out at the same time using the same cow for both techniques and DMD was estimated at 6, 12, 24, 48 & 96 h. The results showed that DMD from Gas were lower than NB DMD and the correlation for the maize group were lower than those of the grass group which indicated that Gas technique, closed system, has potential to analyse highly soluble substrates, probably, overcoming the particle losses effect demonstrated by the in situ technique.
Sugar cane and maize silage samples were evaluated by the semi automated in vitro gas production technique. The associations between gas production and dry matter degradation (DMD) were analysed and high coefficients of determination were obtained for all the substrates. The results showed that particles losses could be influencing the DMD, including errors mostly when obtained before 6 hours of incubation. The gas alone could better predict the lag phase than the DMD before 6 hours of incubation.
This study evaluated the impact of maternal vaccination against rubella on the levels of specific rubella IgG (rIgG) in 198 newborn cord sera samples. Detailed maternal vaccination data were available. Specific rIgG was measured using a commercial enzyme immunoassay. Most mothers (78.8%) had been vaccinated against rubella at least once in their lives. In 15 (7.6%) cord sera samples, the concentration of specific rIgG was below 11 IU/ml, which was classified as seronegative. Statistical analysis using multiple logistic regression (n = 198) showed that newborns of mothers born between 1986 and 1995, and those born to unvaccinated mothers, were more likely to be seronegative (odds ratio (ORs) 5.2 and 4.9, respectively, adjusted for sex and gestational age). For vaccinated mothers (n = 156), those born between 1986 and 1995 were more likely to have seronegative newborns (OR 11.5 adjusting for sex, gestational age and time since last vaccination). Mothers of the 15 (7.6%) seronegative newborns might have been susceptible to rubella during pregnancy. Checking the vaccination status therefore recommended.
Human strongyloidiasis is caused by helminth Strongyloides stercoralis. It has a worldwide distribution, often neglected and cause of severe morbidity. The parasitological diagnosis is hindered by the low and irregular amount of larvae in feces. The goal of the present study was to detect IgG and IgG immune complex using conventional serum samples and saliva as alternative samples. We collected samples from 60 individuals, namely: group I composed of 30 healthy individuals; and group II composed of 30 individuals eliminating S. stercoralis larvae in feces. We calculated the area under the curve, general index of diagnostic accuracy, Kappa index and determined the correlations between different diagnostic tests. The detection of IgG levels was performed by an immunoenzymatic assay with alkaline extract of S. venezuelensis larvae as antigen. Positivity of anti-S. stercoralis IgG in serum samples from group I was 3·3%, and from group II 93·3%. The detection of immune complex indicated that group I exhibited 3·3% and group II 56·7%. In the saliva samples, IgG detection was 26·7% for group I and 43·3% for group II. Immune complex was detected in 20% of group I, and 30% of group II. IgG immune complex in conventional serum samples and saliva as alternative samples can be considered biomarkers for the diagnosis of active strongyloidiasis.
Environmental regulations as well as economic incentives have resulted in greater use of synthetic amino acids in swine diets. Tryptophan is typically the second limiting amino acid in corn-soybean meal-based diets. However, using corn-based co-products emphasizes the need to evaluate the pig’s response to increasing Trp concentrations. Therefore, the objective of these studies was to evaluate the dose–response to increasing standardized ileal digestible (SID) Trp : Lys on growth performance of growing-finishing gilts housed under large-scale commercial conditions. Dietary treatments consisted of SID Trp : Lys of 14.5%, 16.5%, 18.0%, 19.5%, 21.0%, 22.5% and 24.5%. The study was conducted in four experiments of 21 days of duration each, and used corn-soybean meal-based diets with 30% distillers dried grains with solubles. A total of 1166, 1099, 1132 and 975 gilts (PIC 337×1050, initially 29.9±2.0 kg, 55.5±4.8 kg, 71.2±3.4 kg and 106.2±3.1 kg BW, mean±SD) were used. Within each experiment, pens of gilts were blocked by BW and assigned to one of the seven dietary treatments and six pens per treatment with 20 to 28 gilts/pen. First, generalized linear mixed models were fit to data from each experiment to characterize performance. Next, data were modeled across experiments and fit competing dose–response linear and non-linear models and estimate SID Trp : Lys break points or maximums for performance. Competing models included broken-line linear (BLL), broken-line quadratic and quadratic polynomial (QP). For average daily gain (ADG), increasing the SID Trp : Lys increased growth rate in a quadratic manner (P<0.02) in all experiments except for Exp 2, for which the increase was linear (P<0.001). Increasing SID Trp : Lys increased (P<0.05) feed efficiency (G : F) quadratically in Exp 1, 3 and 4. For, ADG the QP was the best fitting dose–response model and the estimated maximum mean ADG was obtained at a 23.5% (95% confidence interval (CI): [22.7, 24.3%]) SID Trp : Lys. For maximum G : F, the BLL dose–response models had the best fit and estimated the SID Trp : Lys minimum to maximize G : F at 16.9 (95% CI: [16.0, 17.8%]). Thus, the estimated SID Trp : Lys for 30 to 125 kg gilts ranged from a minimum of 16.9% for maximum G : F to 23.5% for maximum ADG.
The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals’ species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR for Bartonella spp. based on nuoG gene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained for Bartonella (nuoG) (n = 3), gltA (n = 2), rpoB (n = 1), ftsZ (n = 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, the Bartonella sequences clustered with Bartonella genotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation of Bartonella spp. and hemoplasmas among bats in Brazil.
Blastocystis sp. is a protozoan commonly found in human and animal stool samples. Several pathogenic and zoonotic aspects of this organism are still unknown. The aim of the present study was to investigate Blastocystis subtypes (STs) in samples from patients of the Hospital das Clínicas of the Faculdade de Medicina at the Universidade de São Paulo (HC-FMUSP), Brazil. Blastocystis sp.-positive stool samples diagnosed at the Section of Parasitology of the Central Laboratory (HC-FMUSP) were used for DNA isolation. Polymerase chain reaction (PCR) was performed using specific primers targeting the small-subunit rRNA gene. Direct DNA sequencing of the PCR products was performed and the DNA sequences were then aligned and compared with other sequences obtained from the GenBank database. Phylogenetic analysis was used to identify STs and determine the phylogenetic relationships between the sequences. Four STs were identified: ST1 (22·5%), ST2 (12·5%), ST3 (60%) and ST6 (5%). In conclusion, ST3 was the most prevalent ST among the human isolates followed by ST1. The present study is one of the few providing STs data from the human population in South America. Determining ST prevalence in human samples may contribute to the monitoring of Blastocystis sp. infection transmission in endemic regions.
Strongyloides venezuelensis is a parasitic nematode of rodents that is frequently used to obtain heterologous antigens for immunological diagnosis of human strongyloidiasis. The aim of this study was to identify antigens from filariform larvae of S. venezuelensis for immunodiagnosis of human strongyloidiasis. Soluble and membrane fractions from filariform larvae of S. venezuelensis were obtained in phosphate saline (SS and SM) and in Tris–HCl buffer (TS and TM), and were analysed by Western blotting. Different antigenic components were recognized by IgG antibodies from the sera of strongyloidiasis patients. Highest recognition was observed for a 30–40 kDa mass range present in all antigenic fractions. The band encompassing this mass range was then excised and subjected to mass spectrometry for protein identification. Immunoreactive proteins identified in the soluble fractions corresponded to metabolic enzymes, whereas cytoskeletal proteins and galectins were more abundant in the membrane fractions. These results represent the first approach towards identification of S. venezuelensis antigens for use in immunodiagnostic assays for human strongyloidiasis.
In Portugal, the recommended age for the second dose of MMR (MMR2) was changed from 10–13 years to 5–6 years for those born in 1994 and afterwards. This study aimed to assess if MMR schedule and time elapsed from the last dose are associated with the concentration of rubella and mumps IgG antibodies. Three Portuguese birth cohorts (convenience samples) were selected for this study (66, 59 and 41 participants born respectively in 1990–1993, 1994–1995 and 2001–2003). Geometric mean concentrations (GMC) for mumps IgG were respectively 36, 30 and 38 RU/ml (P = 0·236) and for rubella IgG were 18, 20 and 17 IU/ml (P = 0·641). For both specific antibodies, no differences were observed with time since MMR2. Receiving MMR2 at 5–6 or 10–13 years was not associated with concentration of both antibodies. The GMC of rubella IgG was lower in males (P = 0·029). Taking into account previous evidence and the logistics needed to change vaccination schedules, it seems reasonable that sustaining very high coverage with two doses of MMR is currently the most pragmatic way to control mumps and rubella rather than any changes to the schedule.
Episodes of depression and anxiety (D&A) during the transition from late adolescence to adulthood, particularly when persistent, are predictive of long-term disorders and associated public health burden. Understanding risk factors at this time is important to guide intervention. The current objective was to investigate the associations between maternal symptoms of D&A with offspring symptoms during their transition to adulthood.
Data from a large population-based birth cohort study, in South Brazil, were used. Prospective associations between maternal D&A and offspring risk of these symptoms during the transition to adulthood (18/19, 24 and 30 years) were estimated.
Maternal D&A in adolescence was associated with offspring symptoms across the transition to adulthood, associations were consistently stronger for females than for males. Daughters whose mothers reported D&A were 4.6 times (95% confidence interval 2.71–7.84) as likely to report D&A at all three time-points, than daughters of symptom-free mothers.
Maternal D&A is associated with persistent D&A during the daughter's transition to adulthood. Intervention strategies should consider the mother's mental health.
Definitive diagnosis of strongyloidiasis in humans is typically achieved by detection of larvae in fecal samples. However, limitations on sensitivity of parasitological methods emphasize the need for more robust diagnostic methods. The aim of this study was to compare the diagnostic value of three methods: eggs per gram of feces (EPG), coproantigen detection by enzyme linked immunosorbent assay (ELISA), and DNA detection by conventional polymerase chain reaction (PCR). The assays were performed at 0 and 5, 8, 13, 21 and 39 days post-infection (dpi) using fecal samples from experimentally infected immunocompetent and immunosuppressed rats. In immunocompetent rats, eggs were detected in feces on days 5, 8 and 13 dpi; coproantigen detection and PCR amplification were successful at all post-infection time points (5, 8, 13, 21 and 39 dpi). In immunosuppressed rats, eggs were detected at 5, 8, 13 and 21; coproantigen detection and PCR amplification were successful at all post-infection time points. In conclusion, these results suggest that coproantigen detection and PCR may be more sensitive alternatives to traditional methods such as EPG for diagnosis of Strongyloides venezuelensis infection.
The present study aimed to evaluate the effect of dietary cation–anion difference (DCAD) on ruminal fermentation, total apparent digestibility, blood and renal metabolism of lactating dairy cows. Sixteen Holstein cows were distributed in four contemporary 4×4 Latin Square designs, which consisted of four periods of 21 days and four treatments according to DCAD: +290; +192; +98 and −71 milliequivalent (mEq)/kg dry matter (DM). Ruminal pH and concentrations of acetic and butyric acid increased linearly according to the increase of DCAD. Similarly, NDF total apparent digestibility linearly increased by 6.38% when DCAD increased from −71 to 290 mEq/kg DM [Y=65.90 (SE=2.37)+0.0167 (SE=0.0068)×DCAD (mEq/kg DM)]. Blood pH was also increased according to DCAD, which resulted in reduction of serum concentrations of Na, K and ionic calcium (iCa). To maintain the blood acid–base homeostasis, renal metabolism played an important role in controlling serum concentrations of Na and K, since the Na and K urinary excretion increased linearly by 89.69% and 46.06%, respectively, from −71 to 290 mEq/kg DM. Changes in acid–base balance of biological fluids may directly affect the mineral composition of milk, as milk concentrations of Na, K, iCa and chlorides were reduced according to blood pH increased. Thus, it can be concluded that the increase of DCAD raises the pH of ruminal fluid, NDF total apparent digestibility, and blood pH, and decreases the milk concentration of cationic minerals, as well as the efficiency of Na utilization to milk production.
The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) is a narrow-band imaging, very wide field cosmological survey. It will last 5 years and will observe 8500 sq. deg. of the sky. There will be 54 contiguous narrow-band filters of 145Å FWHM, from 3,500 to 10,000Å. Two broad-band filters will be added at the extremes, UV and IR, plus the 3–g, r, and i– SDSS filters. Thus, J-PAS can be an important tool to search for new planetary nebulae (PNe) at the halo, increasing their numbers, because only 14 of them have been convincingly identified in the literature. Halo PNe are able to reveal precious information for the study of stellar evolution and the early chemical conditions of the Galaxy. The characteristic low continuum and intense emission lines of PNe make them good objects to be searched by J-PAS. Though covering a significantly smaller sky area, data from the ALHAMBRA survey were used to test our J-PAS strategy to search for PNe. Our first results are shown in this contribution.