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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.
Forage cactus is an important dry-season feed source for livestock in semi-arid regions, but in north-eastern Brazil, its contribution is limited by susceptibility to the carmine cochineal [Dactylopius opuntiae (Cockerell)] insect. New cactus germplasm shows superior agronomic performance, but the nutritive value of this material has not been adequately described. The objective of the current study was to assess the divergence in chemical composition and rate and extent of in vitro degradation of these genotypes. The treatments were 13 spineless cactus genotypes, eight of which were insect resistant types, two semi-resistant and three susceptible to the carmine cochineal. Treatments were arranged in a randomized complete block design and were replicated three times. Nutritional divergence was assessed using canonical variate analysis and hierarchical agglomerative clustering, using the variables: crude protein, total and non-fibrous carbohydrates, degradation rate and potential dry matter degradation. Five distinct nutritional groups were identified: Group I (OO), Group II (F-13 and F-15), Group III (OEA, OEM, COP, IPA 20 and GG), Group IV (V-16 and F-08) and Group V (Miuda, IS and F-21). Group II (F-13 and F-15; resistant genotypes) showed a chemical composition degradability in vitro suggesting it may have the greatest nutritive value as ruminant feed, while Group I had the least. Spineless cactus genotypes resistant to the carmine cochineal showed nutritional characteristics similar to or better than traditionally used cactus genotypes, such as Gigante and IPA 20, which can expand the range of options for using this forage.
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.
By using an experimental model of dexamethasone-induced osteoporosis we investigated the effects of different therapeutic schemes combining sodium alendronate (SA) and simvastatin on bone mineral and protein composition, microstructural and mechanical remodeling. Wistar rats were randomized into eight groups: G1: non-osteoporotic; G2: osteoporotic; G3, G4, and G5: osteoporotic+SA (0.2, 0.4, and 0.8 mg/kg, respectively); G6, G7, and G8: osteoporotic+SA (0.2, 0.4, and 0.8 mg/kg, respectively)+simvastatin (0.4, 0.6, and 1 mg/kg, respectively). Osteoporosis was induced by dexamethasone (7 mg/kg, i.m.) once a week for 5 weeks. All treatments were administered for 8 weeks. Dexamethasone increased serum levels of alkaline phosphatase, calcium, phosphorus, and urea, especially in non-treated animals, which showed severe osteoporosis. Dexamethasone also induced bone microstructural fragility and reduced mechanical resistance, which were associated with a marked depletion in mineral mass, collagenous and non-collagenous protein levels in cortical and cancellous bone. Although SA has attenuated osteoporosis severity, the effectiveness of drug therapy was enhanced combining alendronate and simvastatin. The restoration in serum parameters, organic and inorganic bone mass, and mechanical behavior showed a dose-dependent effect that was potentially related to the complementary mechanisms by which each drug acts to induce bone anabolism, accelerating tissue repair.
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.
Pearl millet (Pennisetum glaucum (L.) R.) could play an important role as a feed source for ruminants in arid and semi-arid zones of the world owing to its high yield and drought tolerance. The current paper assessed the agronomic characteristics, ensilability, intake and digestibility of five Brazilian pearl millet cultivars (IPA Bulk1BF, BRS 1501, CMS-03, CMS-01 and BN-2) in a typical Brazilian northeastern semi-arid climate. Forage was harvested at the dough stage of grain maturity (growth stage 86 according to the BBCH scale) and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 25 Santa Inês male lambs. The cultivars CMS-01, CMS-03 and BN-2 out-performed the others in terms of dry matter (DM) and digestible DM yield/ha. At DM partitioning among plant tissues, the cultivar IPA Bulk1BF had a greater DM associated with panicles and one of the greatest concentrations of organic matter, lactic acid and in vitro dry matter digestibility among the five cultivars. The cultivar BRS 1501 had greater butyric acid concentration as well as one of the highest pH values. Silage produced from BN-2 not only contained greater acetic acid concentration, but also showed one of the greatest total volatile fatty acid concentrations. There were no differences in feed intake and digestibility of nutrients and fibre fractions across all cultivars. Silage made from BN-2 resulted in greater urinary excretion of nitrogen than those produced from BRS 1501. Under the conditions of the present study, the results obtained for production of DM and digestible dry matter, and the ratio of plant fractions, indicates the possible use of these cultivars for silage production in the Brazilian semi-arid region.
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.
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.
In vitro batch cultures were used to screen four fibrolytic enzyme mixtures at two dosages added to a 60 : 40 silage : concentrate diet containing the C4 tropical grass Andropogon gayanus grass ensiled at two maturities – vegetative stage (VS) and flowering stage (FS). Based on these studies, one enzyme mixture was selected to treat the same diets and evaluate its impact on fermentation using an artificial rumen (Rusitec). In vitro batch cultures were conducted as a completely randomized design with two runs, four replicates per run and 12 treatments in a factorial arrangement (four enzyme mixtures×three doses). Enzyme additives (E1, E2, E3 and E4) were commercial products and contained a range of endoglucanase, exoglucanase and xylanase activities. Enzymes were added to the complete diet 2 h before incubation at 0, 2 and 4 μl/g of dry matter (DM). Gas production (GP) was measured after 3, 6, 12, 24 and 48 h of incubation. Disappearance of DM (DMD), NDF (NDFD) and ADF (ADFD) were determined after 24 and 48 h. For all four enzyme mixtures, a dosage effect (P<0.05) was observed for NDFD and ADFD after 24 h and for DMD, NDFD and ADFD after 48 h of incubation of the VS diet. For the FS diet, a dosage effect was observed for GP and NDFD after 24 h and for GP, DMD, NDFD and ADFD after 48 h of incubation. There was no difference among enzyme mixtures nor was there an enzyme×dose interaction for the studied parameters. Because of the greatest numerical effect on NDF disappearance and the least cost price, enzyme mixture E2 at 4 µl/g of diet DM was selected for the Rusitec experiment. The enzyme did not impact (P>0.05) DM, N, NDF or ADF disappearance after 48 h of incubation nor daily ammonia-N, volatile fatty acids or CH4 production. However, enzyme application increased (P<0.05) microbial N production in feed particle-associated (loosely-associated) and silage feed particle-bound (firmly associated) fractions. With A. gayanus silage diets, degradation may not be limited by microbial colonization, but rather by the ability of fibrolytic enzymes to degrade plant cell walls within this recalcitrant forage.
New elasmosaurid plesiosaur specimens are described from the Early Maastrichtian of Angola. Phylogenetic analyses reconstruct the Angolan taxon as an aristonectine elasmosaurid and the sister taxon of an unnamed form of similar age from New Zealand. Comparisons also indicate a close relationship with an unnamed form previously described from Patagonia. All of these specimens exhibit an ostensibly osteologically immature external morphology, but histological analysis of the Angolan material suggests an adult with paedomorphic traits. By extension, the similarity of the Angolan, New Zealand and Patagonian material indicates that these specimens represent a widespread paedomorphic yet unnamed taxon.
This paper deals with the stiffness analysis of multibody systems using the Matrix Structural Analysis—MSA. This methodology allows us to obtain the stiffness matrix of the structure from the stiffness properties of each element. First the MSA method is described and its application is detailed using an L-structure in order to make easy its understanding. Numerical and experimental results obtained for the L-structure and a 6-RSS parallel manipulator, follow to prove the validity of the methodology.
We report here a new elasmosaurid from the early Maastrichtian at Bentiaba, southern Angola. Phylogenetic analysis places the new taxon as the sister taxon to Styxosaurus snowii, and that clade as the sister of a clade composed of (Hydrotherosaurus alexandrae (Libonectes morgani + Elasmosaurus platyurus)). The new taxon has a reduced dorsal blade of the scapula, a feature unique amongst elasmosaurids, but convergent with cryptoclidid plesiosaurs, and indicates a longitudinal protraction-retraction limb cycle rowing style with simple pitch rotation at the glenohumeral articulation. Morphometric phylogenetic analysis of the coracoids of 40 eosauropterygian taxa suggests that there was a broad range of swimming styles within the clade.
Wild canids are potential hosts for numerous species of Bartonella, yet little research has been done to quantify their infection rates in South America. We sought to investigate Bartonella seroprevalence in captive wild canids from 19 zoos in São Paulo and Mato Grosso states, Brazil. Blood samples were collected from 97 wild canids belonging to four different native species and three European wolves (Canis lupus). Indirect immunofluorescent antibody testing was performed to detect the presence of B. henselae, B. vinsonii subsp. berkhoffii, B. clarridgeiae, and B. rochalimae. Overall, Bartonella antibodies were detected in 11 of the canids, including five (12·8%) of 39 crab-eating foxes (Cerdocyon thous), three (11·1%) of 27 bush dogs (Speothos venaticus), two (8·7%) of 23 maned wolves (Chrysocyon brachyurus) and one (12·5%) of eight hoary foxes (Lycalopex vetulus), with titres ranging from 1:64 to 1:512. Knowing that many species of canids make excellent reservoir hosts for Bartonella, and that there is zoonotic potential for all Bartonella spp. tested for, it will be important to conduct further research in non-captive wild canids to gain an accurate understanding of Bartonella infection in free-ranging wild canids in South America.
Objective: Considering that mitochondria may be drug targets and some characteristics of drug–mitochondria interactions may still be misjudged because of the difficulty in foreseeing and understanding all possible implications of the complex pathophysiology of mitochondria, our study aimed to investigate the effect of escitalopram on the activity of enzymes of mitochondrial energy metabolism.
Methods: Animals received daily administration of escitalopram dissolved in saline [10 mg/kg, intraperitoneal (IP)] at 1.0 ml/kg volume for 14 days. Control rats received an equivalent volume of saline, 1.0 ml/kg (IP), for the same treatment period. Twelve hours after last injection, rats were killed by decapitation and brain areas were rapidly isolated. The samples were homogenised and the activities of mitochondrial respiratory chain complexes, some enzymes of Krebs cycle (citrate synthase, malate dehydrogenase and succinate dehydrogenase) and creatine kinase were measured.
Results: We verified that chronic administration of escitalopram decreased the activities of complexes I and II–III in cerebellum, hippocampus, striatum and posterior cortex whereas prefrontal cortex was not affected. Complex II activity was decreased only in striatum without affecting prefrontal cortex, hippocampus, cerebellum and posterior cortex. However, chronic administration of escitalopram did not affect complex IV and enzymes of Krebs cycle activities as well as creatine kinase.
Conclusion: In this study we showed a decrease in the activities of complexes I and II–III in most of the brain structures analysed and complex II activity was decreased only in striatum. However, it remains to be determined if mitochondrial dysfunction is rather a causal or a consequential event of abnormal signalling.
Objectives: Based on the hypothesis that energy impairment may be involved in the pathophysiology of depression, we evaluated the activities of citrate synthase, malate dehydrogenase, succinate dehydrogenase (SDH), mitochondrial respiratory chain complexes I, II, II-III, IV and creatine kinase (CK) in the brain of rats submitted to chronic administration of bupropion.
Methods: Animals received daily administration of bupropion dissolved in saline (10 mg/kg, intraperitoneal) at 1.0 ml/kg body weight. The rats received injections once a day for 14 days; control rats received an equivalent volume of saline. Twelve hours after the last administration, the rats were killed by decapitation and brain was rapidly removed and kept on an ice plate. The activities of the enzymes were measured in different brain areas.
Results: We observed that the activities of citrate synthase and malate dehydrogenase, mithocondrial respiratory chain complexes I, II-III and IV and CK were not altered after chronic administration of bupropion. However, SDH activity was increased in the prefrontal cortex and cerebellum. In the hippocampus, cerebellum and striatum the activity of complex II was increased after chronic administration of bupropion.
Conclusions: Our results demonstrated that bupropion increased some enzymes of brain energy metabolism. These findings are in accordance with other studies which showed that some antidepressants may improve energy metabolism. The present results reinforce the hypothesis that antidepressants modulate brain energy metabolism.
The aim of this study was to use larval, parasitic female and egg antigens from Strongyloides venezuelensis to detect parasite-specific IgG and immune complexes in human serum samples by enzyme-linked immunosorbent assay (ELISA). In total, 95 serum samples were analysed, consisting of 30 patients harbouring S. stercoralis larvae, 30 healthy subjects and 35 patients with other parasites. Sensitivity, specificity and diagnostic efficiency were calculated. A significant statistical difference was found in the detection of immune complexes and antibodies in patients harbouring S. stercoralis larvae from larval and eggs antigens, with higher positivity using larval antigen. The larval antigen showed the highest values for sensitivity, specificity and diagnostic efficiency in ELISA from detection of immune complexes. For the first time we used IgG anti-larvae, IgG anti-parasitic females or IgG anti-eggs for immune complex detection. We concluded that the association of antibody and immune complex detection could be used in the diagnosis of human strongyloidiasis.
Rheumatoid arthritis (RA) is a chronic inflammatory disease that mainly targets the synovial membrane, cartilage and bone. It affects 1 % of the population and is associated with significant morbidity and increased mortality. Se is an essential trace element with antioxidant properties and the ability to modulate the immune responses. Selemax® is an inactive yeast (Saccharomyces cerevisiae) enriched with organic Se. The aim of the present study was to investigate the effects of Selemax® administration in models of an antigen-induced arthritis (AIA) in C57BL/6 mice, and of an adjuvant-induced arthritis (AdIA) in Holtzman rats. As control, the animals were treated with the same inactivated yeast species that was not enriched for Se. In the AIA model, treatment with different doses of Selemax® (0·01, 0·1, 1 and 10 % added to food) significantly decreased the number of inflammatory cells recruited to the knee cavity, essentially by reducing the number of neutrophils. Levels of proinflammatory cytokines, including TNF-α, IL-1β and chemokine (C-X-C motif) ligand 1/keratinocyte chemoattractant (CXCL1/KC), were also reduced in the peri-articular tissue of mice treated with Selemax® at the tested dose (1 %). In the AdIA model in rats, Selemax® treatment decreased paw oedema and hypernociception. This reduction was associated with inhibition of the influx of proinflammatory cells. Therefore, treatment with Selemax® is associated with amelioration of several inflammatory and functional parameters in models of arthritis, suggesting that this Se-enriched yeast should be evaluated further in patients with RA.
An outbreak of meningococcal disease (MD) with severe morbidity and mortality was investigated in midwestern Brazil in order to identify control measures. A MD case was defined as isolation of Neisseria meningitidis, or detection of polysaccharide antigen in a sterile site, or presence of clinical purpura fulminans, or an epidemiological link with a laboratory-confirmed case-patient, between June and August 2008. In 8 out of 16 MD cases studied, serogroup C ST103 complex was identified. Five (31%) cases had neurological findings and five (31%) died. The attack rate was 12 cases/100 000 town residents and 60 cases/100 000 employees in a large local food-processing plant. We conducted a matched case-control study of eight primary laboratory-confirmed cases (1:4). Factors associated with illness in single variable analysis were work at the processing plant [matched odds ratio (mOR) 22, 95% confidence interval (CI) 2·3–207·7, P<0·01], and residing <1 year in Rio Verde (mOR 7, 95% CI 1·11–43·9, P<0·02). Mass vaccination (>10 000 plant employees) stopped propagation in the plant, but not in the larger community.