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The effects of growing pinto peanut mixed with elephant grass-based pastures are still little known. The aim of the current research was to evaluate the performance of herbage yield, nutritive value of forage and animal responses to levels of pinto peanut forage mass mixed with elephant grass in low-input systems. Three grazing systems were evaluated: (i) elephant grass-based (control); (ii) pinto peanut, low-density forage yield (63 g/kg of dry matter – DM) + elephant grass; and (iii) pinto peanut, high-density dry matter forage yield (206 g/kg DM) + elephant grass. The experimental design was completely randomized with the three treatments (grazing systems) and three replicates (paddocks) in split-plot grazing cycles. Forage samples were collected to evaluate the pasture and animal responses. Leaf blades of elephant grass and the other companion grasses of pinto peanut were collected to analyse the crude protein, in vitro digestible organic matter and total digestible nutrients. The pinto peanut, high-density dry matter forage yield + elephant grass treatment was found to give the best results in terms of herbage yield, forage intake and stocking rate, as well as having higher crude protein contents for both elephant grass and the other grasses, followed by pinto peanut with low-density forage yield + elephant grass and finally elephant grass alone. Better results were found with the grass–legume system for pasture and animal responses.
Differences in forage nutritive value between morning and afternoon are related to patterns of dehydration and carbohydrate accumulation throughout the day. In this way, management strategies that maximize grazing time during the afternoon could increase forage nutritive value and consequently nutrient intake. The aim of the current experiment was to evaluate the effect of the time of day (06.00 h [designated AM] or 15.00 h [PM]) that cattle are moved to a new paddock on forage nutritive value, grazing behaviour and animal performance of beef cattle on rotationally stocked Marandu palisadegrass (Brachiaria brizantha cv. Marandu Syn. Urochloa brizantha cv. Marandu) pastures. A spring and summer study was conducted in Pirassununga, SP, Brazil from October 2012 to March 2013 (182 days). Treatments were distributed in a randomized complete block design with three replications. Herbage mass, morphological composition, herbage allowance and stocking rates were similar between treatments during spring and summer. Moving animals to a new paddock, regardless of the time of day – 06.00 h (AM) or 15.00 h (PM) – stimulated grazing, modifying the distribution of meals throughout the day. However, compensatory mechanisms among grazing time, bite rate and forage nutritive value throughout the day operated in order to generate similar performance between animals offered a new paddock in the morning or in the afternoon.
Forage is the primary feed source for livestock in tropical regions and energy is one of the most important nutrients for ruminant nutrition. The effects of harvest management of Marandu palisade grass (Brachiaria brizantha cv. Marandu Syn. Urochloa brizantha cv. Marandu) on non-structural carbohydrate (NSC) concentrations were evaluated. A plot (Experiment 1) and a greenhouse study (Experiment 2) were conducted in 2013–14. In Experiment 1, treatments were the factorial arrangement of two harvest times and two vertical canopy layers (upper and intermediate), distributed in a completely randomized design with five replicates. In Experiment 2, treatments were the factorial arrangement of six harvest times and two morphological fractions (leaf blade and pseudostem). In both experiments, NSC concentration increased during the day. Upper and intermediate canopy layers had greater NSC concentration at 15.00 than 06.00 h during spring and summer. In addition, the magnitude of NSC increase was greater in the upper than intermediate canopy layer and in spring than summer. Marandu palisade grass shows greater digestibility in the afternoon than morning, representing an opportunity to optimize energy concentration through harvest management.
Isotopic composition of leaf carbon (δ13C) and nitrogen (δ15N) is determined by biotic and abiotic factors. In order to determine the influence of leaf habit and site on leaf δ13C and δ15N in the understorey of two Atlantic forests in Brazil that differ in annual precipitation (1200 and 1900 mm), we measured these isotopes in the shaded understorey of 38 tropical tree species (20 in the 1200-mm site and 18 in the 1900-mm site). Mean site values for δ15N were significantly lower at the 1200-mm site (−1.4‰) compared with the 1900-mm site (+3.0‰), and δ13C was significantly greater in the 1200-mm site (−30.4‰) than in the 1900-mm site (−31.6‰). Leaf C concentration was greater and leaf N concentration was lower at 1200-mm than at 1900-mm. Leaf δ15N was negatively correlated with δ13C across the two sites. Leaf δ13C and δ15N of evergreen and deciduous species were not significantly different within a site. No significant phylogenetic signal for any traits among the study species was found. Overall, site differences were the main factor distinguishing traits among species, suggesting strong functional convergence to local climate and soils within each site for individuals in the shaded understorey.
In the traditional silvo–pastoral system, Alentejano pigs are fattened with acorns and pasture. Although this production system (“Montanheira”) has been characterised, there is a lack of knowledge on intake and digestibility of the diet, mainly due to the absence of tested methodologies in pigs. The n–alkane technique, extensively used in ruminants to estimate diet intake and digestibilitiy, has had less use in pigs. The objective of this experiment was to validate the n–alkane technique in Alentejano pigs. Faecal recoveries of natural and dosed n-alkanes, the diurnal variation of faecal n–alkane concentration, and the time span required to reach a steady state excretion of dosed alkanes were determined. Eight male Alentejano pigs (54.4±9.8 kg LW) were randomly allocated to two groups and placed in metabolic cages. They were fed 0.7 kg of pasture and 0.7kg of ground acorns daily as two meals. Pigs in Group-1 were given once daily artificial C32 (40mg/d) and C36 (40 mg/d) and those in Group-2 the same alkanes as two daily doses of 20 mg. Steady state excretion of both alkanes was reached 3 days after first dosing. Although no difference (P>0.05) was observed between treatments, the coefficient of variation of feacal alkane concentration when dosed twice daily was generally lower than when dosed once daily. Mean faecal recoveries of n–alkanes increased with increasing carbon-chain length (C25 to C36) from 38 to 69%, but were not significantly different from C29, C32, C33 and C36 (mean 0.694 SEM 0.067). Faecal nalkanes in samples collected every four hours for three days showed no diurnal variation in patterns of excretion apart from a higher concentration of C32 4 hours after dosing once daily. However variation between animals was lower when artificial alkanes were dosed twice daily than when once daily. The results indicate that the n–alkane techique may be used to estimate intake and digestibility under “Montanheira”, although further validation work needs to be done.
If one interprets China's sizable rise in Latin America as an unprecedented phenomenon, it follows that the concurrent story of declining U.S. influence in the region is an event hastily acknowledged at best and ignored at worst. In this article, we ask whether Chinese economic statecraft in Latin America is related to the declining U.S. hegemonic influence in the region and explore how. To do so we analyze foreign direct investments, bank loans, and international trade from 2003 to 2014, when China became a major player in the region. We use data from 21 Latin American countries, and find that an inversely proportional relationship exists between the investments made by Chinese state-owned enterprises (SOEs), bank loans, manufacturing exports, and the U.S. hegemonic influence exerted in the region. In other words, Beijing has filled the void left by a diminished U.S. presence in the latter's own backyard.
Eight new species of Pyrenulaceae are described as new to science from Brazil, Guyana and Puerto Rico. Pyrenula sanguineomeandrata Aptroot & Mercado Diaz (with a thallus with red, KOH+ purple pigmentation of lines or a reticulum, simple ascomata with vertical ostioles, a deep red inspersed, KOH+ orange hamathecium, and dark brown 3-septate ascospores 25–29×10–12 μm) and P. sanguineostiolata Aptroot & Mercado Diaz (with a thallus with deeply immersed simple ascomata with vertical ostioles, which are superficial and bright red, and 3-septate ascospores 25–28×9–12 μm) are described from submontane evergreen forests in Puerto Rico. Pyrenula biseptata Aptroot & M. Cáceres (with simple ascomata with vertical ostioles, an inspersed hamathecium and 2-septate ascospores 11–12×4·5–5·0 μm) and P. xanthinspersa Aptroot & M. Cáceres (with an ecorticate thallus containing lichexanthone, simple ascomata with vertical ostioles, not inspersed hamathecium and 3-septate ascospores 14–17×6·0–7·5 μm) are described from rainforest in Amazonian Brazil. Pyrenula subvariabilis Aptroot & Sipman (with fused ascomata with lateral ostioles and submuriform ascospores 17–20(–25)×6–9 μm) and Sulcopyrenula biseriata Aptroot & Sipman (with a thallus containing lichexanthone, simple ascomata with lateral ostioles and lozenge-shaped ascospores with 8 locules, (13–)15–17(–20)×8–10 (width)×6–7 (thickness) μm) are described from savannahs in Guyana. Special attention is paid to the genus Pyrgillus: two new species from the 3-septate core group of this small genus are described from Brazil, viz. P. aurantiacus Aptroot & M. Cáceres (with a corticate thallus containing lichexanthone, mazaedium with orange, KOH+ violet, UV+ red pruina and ascospores of 13–16×6·0–7·5 μm) and P. rufus Aptroot & M. Cáceres (with a corticate thallus containing lichexanthone, mazaedium with dark red, KOH+ orange, UV+ red pruina and ascospores of 15·0–17·5×5·0–6·5 μm). An updated key to the 3-septate species of Pyrgillus is provided.
The trans-10, cis-12 conjugated linoleic acid (CLA) causes milk fat depression by downregulating expression of genes and transcription factors involved in lipogenesis and it has been proposed that peroxisome proliferator-activated receptor gamma (PPARγ) can be inhibited by trans-10, cis-12 CLA. The PPARγ is a nuclear receptor activated by natural or synthetic ligands and promotes expression of lipogenic genes and its effect on mammary lipogenesis and the interaction with trans-10, cis-12 CLA in lactating ewes was evaluated using thiazolidinedione (TZD), a chemical PPARγ agonist. A total of 24 lactating ewes were randomly assigned to one of the following treatments for 7 days: (1) Control (5 ml/day of saline solution); (2) TZD (4 mg/kg of BW/day in 5 ml of saline solution); (3) CLA (27 g/day with 29.9% of trans-10, cis-12); (4) TZD+CLA. Compared with Control, milk fat content was not changed by TZD, but was decreased 22.3% and 20.5% by CLA and TZD+CLA treatments. In the mammary gland, TZD increased PPARγ gene expression by 174.8% and 207.8% compared with Control and TZD+CLA treatments, respectively. Conjugated linoleic acid reduced sterol regulatory element-binding transcription protein 1 (SREBP1) gene expression 89.2% and 75.3% compared with Control and TZD+CLA, respectively, demonstrating that TZD fails to overcome CLA inhibition of SREBP1 signaling. In adipose tissue, the expression of SREBP1 and stearoyl CoA desaturase 1 (SCD1) genes were increased by the TZD+CLA treatment, compared with the other treatments. Conjugated linoleic acid decreased milk fat concentration and expression of lipogenic genes, while TZD had no effect on milk fat concentration, expression of lipogenic enzymes or regulators in the mammary gland and failed to overcome the inhibition of these by CLA. Therefore, CLA inhibition of milk fat synthesis was independent of the PPARγ pathway in lactating dairy ewes.
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.
The main limitation for determining feed efficiency of freely grazing ruminants is measurement of daily individual feed intake. This paper describes an investigation that assessed a method for estimating intake of forage based on changes in BW of ewes. A total of 24 dry and non-pregnant Romane ewes (12 hoggets, HOG; mean±SD 51.8±2.8 kg BW; body condition score (BCS) 2.6±0.2; and 12 adults, ADU; 60.4±8.5 kg BW; BCS 2.7±0.8) were selected for the study and moved from their rangeland system to a confined pen with controlled conditions and equipped with individual automatic feeders. The experiment lasted for 28 days (21 days adaptation and 7 days feed intake measurement). Ewes were fed hay and trained to use the electronic feeders (one feeding station per ewe) in which actual daily intake (Hintake24) was measured. The pens were designed to maximize movement of trained ewes through an automated Walk-over-Weighing device, by using water and mineral salts as attractants. Total individual intake of hay measured in the automatic feeder at each meal (Hintake) was compared with indirect estimates of feed intake determined using differences in the BW of the ewes (∆BW) before and 1 h following morning and afternoon feeding at fixed times. The BW, BCS, Hintake, Hintake24, as well as plasma non-esterified fatty acids (NEFA), glucose and insulin profiles were determined. The BW was higher in ADU v. HOG but BCS was not affected by parity. The Hintake24 was affected by day of experiment as a consequence of reduced availability and intake of water on one day. Plasma glucose, NEFA and insulin were not affected by parity or day of experiment. The HIntake was and ∆BW tended to be higher in the morning in HOG, whereas Hintake was and ∆BW tended to be higher in ADU at the afternoon meal. Irrespective of parity or feeding time, there was very strong correlation (r2=0.93) between Hintake and ∆BW. This relationship confirms that our indirect method of estimating individual forage intake was reliable within the strictly controlled conditions of the present experiment. The method appears suitable for use in short-term intensive group feeding situations, and has potential to be further developed for longer-term forage intake studies, with a view to developing a method for freely grazing ruminants.
The house mouse (Mus musculus) and the black rat (Rattus rattus) are reservoir hosts for zoonotic pathogens, several of which cause neglected tropical diseases (NTDs). Studies of the prevalence of these NTD-causing zoonotic pathogens, in house mice and black rats from tropical residential areas are scarce. Three hundred and two house mice and 161 black rats were trapped in 2013 from two urban neighbourhoods and a rural village in Yucatan, Mexico, and subsequently tested for Trypanosoma cruzi, Hymenolepis diminuta and Leptospira interrogans. Using the polymerase chain reaction we detected T. cruzi DNA in the hearts of 4·9% (8/165) and 6·2% (7/113) of house mice and black rats, respectively. We applied the sedimentation technique to detect eggs of H. diminuta in 0·5% (1/182) and 14·2% (15/106) of house mice and black rats, respectively. Through the immunofluorescent imprint method, L. interrogans was identified in 0·9% (1/106) of rat kidney impressions. Our results suggest that the black rat could be an important reservoir for T. cruzi and H. diminuta in the studied sites. Further studies examining seasonal and geographical patterns could increase our knowledge on the epidemiology of these pathogens in Mexico and the risk to public health posed by rodents.
Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.
To describe the results obtained with endolymphatic sac drainage in patients with Ménière's disease.
A retrospective case review study was conducted of 95 Ménière's disease patients who underwent endolymphatic sac drainage in a tertiary care referral centre, after failing a long course of medical management. The main outcome measures were vertigo control and hearing preservation.
In patients with unilateral disease, vertigo control was obtained in 94.3 per cent of patients. A significant improvement in cochlear function was seen in 14 per cent of patients, and hearing was preserved or improved in 88 per cent. For the bilateral group, vertigo control was obtained in 85.7 per cent of patients and cochlear function improved in 28 per cent. Hearing preservation was attained in 71 per cent of these patients.
Endolymphatic sac drainage is a good surgical option for patients with incapacitating endolymphatic hydrops, providing a high percentage of vertigo control and hearing preservation.
The bush dog Speothos venaticus is a medium-sized Neotropical canid. It is considered to be rare and its biology and population parameters are still poorly understood. The Amazon is one of the main strongholds of this species and is important for maintaining viable populations, as the region still holds extensive tracts of pristine habitat. We gathered field data from camera-trap studies throughout the Brazilian Amazon to estimate the relative abundance of the species and gain an understanding of its rarity, and how this compares with estimates from other vegetative formations and for sympatric hypercarnivores. We focused on three pristine or partially disturbed sites and one fragmented site. The estimated relative abundance of the species was 0.060–0.185 individuals per 100 trap-days, confirming that the species is rare. The bush dog's abundance in the Amazon is equivalent to that in all other areas outside the Basin. The mean group size recorded was c. 2.5 individuals. There were no differences in group sizes between forests in the Amazon and in other regions of Central America; however, there were significant differences between forests and open habitats. A combination of competition/predation, habitat structure/integrity, and disease may be acting synergistically in determining the abundance and rarity of bush dogs.
In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, at frequencies of 90, 150, 240 and 410 GHz, with resolution ≳ 10'. The faint structure of the Cosmic Microwave Background at horizon and sub-horizon scales is evident in these maps. These maps compare well to the maps recently obtained at lower frequencies by the WMAP experiment. Here we compare the amplitude and morphology of the structures observed in the two sets of maps. We also outline the polarization sensitive version of BOOMERanG, which was flown early this year to measure the linear polarization of the microwave sky at 150, 240 and 350 GHz.
The experiment, conducted at Bahia, Brazil, from May to August 2010, aimed to evaluate the nitrogen (N) balance, urea excretion and microbial protein synthesis in lactating goats fed pelleted concentrates with the addition of crude protein (CP), obtained by replacing alfalfa hay with soybean meal. The diets consisted of different levels of CP and 200 g of roughage (Tifton 85 hay)/kg. Maize and mesquite bran were used as the energy source, with maize replaced by mesquite bran in the ratio of 1·7:1. Eight female Saanen goats were used, confined in individual pens and allocated to a 4 × 4 Latin square design. The N balance in the body was positive, and loss of body weight (–0·03 g/day) was observed for the diet with 190 g CP/kg. The concentration (mg/dl) of urea in urine, milk and blood plasma was positively influenced in a linear form, and the highest rate of increase was found in urine, with 2 mg/dl for every 10 g CP/kg added to the diet. The microbial protein synthesis was not affected, but the diets reduced the microbial protein (44 g/day) and its ruminal production efficiency (30 g/kg total digestible nutrients). The levels above 190 g of CP are not recommended because of the energy expenditure required to excrete the urea.
Monte Carlo (MC) simulations of the magnetization states of disordered self-assembled arrays of particles consisting of Co87Cu13 alloy are investigated. The assemblies of magnetic particles with ellipsoidal shapes and volumes ranging from 5 to 50 µm3 exhibit densities of about 3 × 106 particles per mm2. Magnetization was obtained in the framework of Stoner–Wohlfarth model extended to include phenomenological contributions of second-order magnetic anisotropy and coercivity mechanism with distinct configuration of easy axes of magnetization. MC simulations for assemblies containing no more than 100 particles with negligible magnetic interaction between each other and exhibiting saturation magnetization and magnetic anisotropy constant values close to those found for cobalt in bulk are in good agreement with experimental results. We evaluate and validate our computational modeling using samples having particles with different sizes and different angular distributions of the easy axis of magnetization. A simple numerical approach with minimum of parameters was used to take into account the coercive fields of the samples. Reasonable simulation results are generated based on realistic size distributions and angular distributions of easy axis of magnetization.
Feeding trans-10, cis-12 CLA to lactating ewes reduces milk fat by down-regulating expression of enzymes involved in lipid synthesis in the mammary gland and increases adipose tissue lipogenesis. Acetyl-CoA carboxylase α (ACC-α) is a key regulated enzyme in de novo fatty acid synthesis and is decreased by CLA. In the ovine, the ACC-α gene is expressed from three tissue-specific promoters (PI, PII and PIII). This study evaluated promoter-specific ACC-α expression in mammary and adipose tissue of lactating cross-bred Lacaune/Texel ewes during milk fat depression induced by rumen-unprotected trans-10, cis-12 CLA supplement. In all, 12 ewes arranged in a completely randomized design were fed during early, mid and late lactation one of the following treatments for 14 days: Control (forage+0.9 kg of concentrate on a dry matter basis) and CLA (forage+0.9 kg of concentrate+27 g/day of CLA (29.9% trans-10, cis-12)). Mammary gland and adipose tissue biopsies were taken on day 14 for gene expression analysis by real-time PCR. Milk fat yield and concentration were reduced with CLA supplementation by 27%, 21% and 35% and 28%, 26% and 42% during early, mid and late lactation, respectively. Overall, our results suggest that trans-10, cis-12 CLA down-regulates mammary ACC-α gene expression by decreasing expression from PII and PIII in mammary gland and up-regulates adipose ACC-α gene expression by increasing expression from PI.
Deviations from ellipticity in the bulges of edge-on disk galaxies, seen as ”boxy“, ”peanut-shaped“, or “X-shaped“ isophotes, have been known for some time (Jarvis 1986, Whitmore & Bell 1988). Contrary to earlier proposals that these features represent accreted material, recent numerical work (Combes et al. 1990; Raha et al. 1991) suggests that they form when the bars in barred galaxies experience a vertical bending instability and deform out of the disk plane. We have found this latter mechanism at work in simulations in which a bar is induced when a large disk galaxy accretes a small companion galaxy, thus incorporating the mechanism into the evolutionary framework of galaxy interactions. In support of this picture we present observations of Hickson 87a, an edge-on S0 galaxy whose morphological peculiarities exactly match those seen in the simulation.