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Sitophilus zeamais is a key pest of stored grains. Its control is made, usually, using synthetic insecticides, despite their negative impacts. Botanical insecticides with fumigant/repellent properties may offer an alternative solution. This work describes the effects of Anethum graveolens, Petroselinum crispum, Foeniculum vulgare and Cuminum cyminum essential oils (EOs) and (S)-carvone, cuminaldehyde, estragole and (+)-fenchone towards adults of S. zeamais. Acute toxicity was assessed by fumigation and topical application. Repellence was evaluated by an area preference bioassay and two-choice test, using maize grains. LC50 determined by fumigation ranged from 51.8 to 535.8 mg L−1 air, with (S)-carvone being the most active. LD50 values for topical applications varied from 23 to 128 µg per adult for (S)-carvone > cuminaldehyde > A. graveolens > C. cyminum > P. crispum. All EOs/standard compounds reduced significantly the percentage of insects attracted to maize grains (65–80%) in the two-choice repellence test, whereas in the area preference bioassay RD50 varied from 1.4 to 45.2 µg cm−2, with cuminaldehyde, (S)-carvone and estragole being strongly repellents. Petroselinum crispum EO and cuminaldehyde affected the nutritional parameters relative growth rate, efficiency conversion index of ingested food and antifeeding effect, displaying antinutritional effects toward S. zeamais. In addition, P. crispum and C. cyminum EOs, as well as cuminaldehyde, showed the highest acetylcholinesterase inhibitory activity in vitro (IC50 = 185, 235 and 214.5 µg mL−1, respectively). EOs/standard compounds exhibited acute toxicity, and some treatments showed antinutritional effects towards S. zeamais. Therefore, the tested plant products might be good candidates to be considered to prevent damages caused by this pest.
Dirofilariosis caused by Dirofilaria immitis (heartworm) is a zoonosis, considered an endemic disease of dogs and cats in several countries of Western Europe, including Portugal. This study assesses the levels of D. immitis exposure in humans from Northern Portugal, to which end, 668 inhabitants of several districts belonging to two different climate areas (Csa: Bragança, Vila Real and Csb: Aveiro, Braga, Porto, Viseu) were tested for anti-D. immitis and anti-Wolbachia surface proteins (WSP) antibodies. The overall prevalence of seropositivity to both anti-D. immitis and WSP antibodies was 6.1%, which demonstrated the risk of infection with D. immitis in humans living in Northern Portugal. This study, carried out in a Western European country, contributes to the characterisation of the risk of infection with D. immitis among human population in this region of the continent. From a One Health point of view, the results of the current work also support the close relationship between dogs and people as a risk factor for human infection
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Heavy weight gilts commonly show signs of oestrus during the late finishing phase, which results in a period of reduced feed intake and growth rate. Immunization against gonadotropin-releasing hormone (GnRH) (IM, immunocastration) was developed for finishing boars and recently extrapolated to females. Immunocastration acts by suppressing reproductive activity and improving the growth potential. The objective of this study was to evaluate the effects of IM on growth performance, reproductive activity and carcass characteristics of late finishing gilts. Seventy-two gilts (63.49 ± 0.39 kg) were either injected with saline (Intact) or immunized against GnRH (Immunized). The study consisted of three experimental periods: between the first to second immunization (V1 to V2, 15 to 19 weeks of age), from the second immunization to the beginning of daily boar exposure (DBE) (V2 to DBE, 19 to 21 weeks of age) and from the beginning of DBE to slaughter (S) (DBE to S, 21 to 25 weeks of age). Immunized gilts showed an overall increase (from 15 to 25 weeks) of 3.90 kg (P < 0.05) of live weight, 56 g (P < 0.05) of average daily gain (ADG) and 250 g (P < 0.001) of average daily feed intake (ADFI). Immunized gilts had a greater ADFI (+240 g, P < 0.05) and worse feed conversion ratio (+0.26, P < 0.05) from 19 (V2) to 21 weeks of age (before DBE). Furthermore, those females had higher feed intake (+410 g; P < 0.001) plus greater daily weight gain (+92 g; P < 0.05) from V2 to S, and from DBE to S (+470 g of ADFI, P < 0.001; +129 g of ADG, P < 0.01, respectively). Immunocastration had no effect on backfat thickness, lean meat percentage and weight, cold carcass yield or loin depth (P > 0.05). Immunized gilts showed 4.4% increased cold carcass weight (P < 0.01) and 10.6% greater gross flank weight (P < 0.001). Immunization against GnRH did not influence shoulder, collar, loin, belly or ham weights. Nor did it influence belly fat thickness, or meat, skin plus fat and bones yields of cold ham (P > 0.05). Immunocastration reduced ovarian and uterine weights by 82% (P < 0.001) and 93% (P < 0.001), respectively, and suppressed oestrus manifestation in all gilts in the immunized group (P < 0.001). These results indicate that immunization against GnRH is a promising tool for stimulating growth performance with no detrimental effects on carcass quality of heavy weight finishing gilts, by means of oestrus suppression.
Excitable temperament disrupts physiological events required for reproductive development in cattle, but no research has investigated the impacts of temperament on growth and puberty attainment in Bos indicus females. Hence, this experiment evaluated the effects of temperament on growth, plasma cortisol concentrations and puberty attainment in B. indicus heifers. A total of 170 Nelore heifers, weaned 4 months before the beginning of this experiment (days 0 to 91), were managed in two groups of 82 and 88 heifers each (mean ± SE; initial BW=238±2 kg, initial age=369±1 days across groups). Heifer temperament was evaluated via exit velocity on day 0. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning heifers with a score from 1 to 5 (1=slowest; 5=fastest heifer). Heifers were classified according to exit score as adequate (ADQ, n=96; exit score⩽3) or excitable temperament (EXC, n=74; exit score>3). Heifer BW, body condition score (BCS) and blood samples were obtained on days 0, 31, 60 and 91. Heifer exit velocity and score were recorded again on days 31, 60 and 91. Ovarian transrectal ultrasonography was performed on days 0 and 10, 31 and 41, 60 and 70, 81 and 91 for puberty evaluation. Heifer was declared pubertal at the first 10-day interval in which a corpus luteum was detected. Exit velocity and exit score obtained on day 0 were correlated (r⩾0.64, P<0.01) with evaluations on days 31, 60 and 91. During the experiment, ADQ had greater (P<0.01) mean BCS and BW gain, and less (P<0.01) mean plasma cortisol concentration compared with EXC heifers. Temperament × time interactions were detected (P<0.01) for exit velocity and exit score, which were always greater (P<0.01) in EXC v. ADQ heifers. A temperament × time interaction was also detected (P=0.03) for puberty attainment, which was delayed in EXC v. ADQ heifers. At the end of the experiment, a greater (P<0.01) proportion of ADQ were pubertal compared with EXC heifers. In summary, B. indicus heifers classified as EXC had reduced growth, increased plasma cortisol concentrations and hindered puberty attainment compared to ADQ heifers. Moreover, exit velocity may serve as temperament selection criteria to optimize development of B. indicus replacement heifers.
Dung beetles (Coleoptera: Scarabaeinae) mediate many ecological functions that are important to maintain the ecosystem functioning of terrestrial environments. Although a large amount of literature explores the dung beetle-mediated ecological processes, little is known about the individual contribution from distinct species. Here, we aimed to examine the intra and interspecific variations in dung burial rates performed by two roller dung beetle species (Canthon smaragdulus Fabricius, 1781 and Canthon sulcatus Castelnau, 1840). Furthermore, we evaluated the relationship between dung beetle biomass and dung burial rates. We set up a laboratorial experiment with three treatments (two males, two females, and a couple) and 10 replicates per treatment for each dung beetle species, and dung burial rates were measured after exposing 100 g of mixed pig and human excrement for 48 hours. Our results demonstrate that dung burial rates of males, females, and couples within each species do not differ. However, C. smaragdulus individuals performed a larger dung burial than C. sulcatus individuals did. In addition, we found no effect of individual biomass on the amount of dung burial on intra and interspecific levels. These findings highlight the need for further research considering that distinct species, even from the same genus, may perform different rates of ecological processes, as well as about the importance for considering the beetle biomass when measuring their ecological functions. We call for studies to fill in the knowledge gap about the individual species’ contribution to the maintenance of different dung beetle-mediated ecological processes.
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.
The aim of this study was to evaluate the distribution of cases and the social determinants associated with death from human visceral leishmaniasis (HVL) and VL–HIV co-infection in Belo Horizonte, Minas Gerais state, Brazil, between 2006 and 2013. Descriptive statistics and analysis of associations were performed using chi-square of the raised variables, such as sex, age, skin colour and schooling of cases of HVL. During the study period, there were 866 cases of HVL with 111 deaths in Belo Horizonte. Morbidity and lethality rates (LR) of HVL in Belo Horizonte remained high over almost all the years evaluated, with an average incidence rate of 4.18 cases/100 000 inhabitants and a LR of 11.16%. With respect to skin colour, it was found that people characterised as black or mulatto had higher morbidity, followed by white. Regarding schooling, LR was more prevalent among individuals with lower education. One of the social risk factors was co-infection with HIV, which was present in many cases of HVL. Furthermore, it was found that older age and the male sex were also risk factors for death from HVL in Belo Horizonte.
Although a national programme for control of visceral leishmaniosis (VL) is being run in Brazil, the disease continues to spread. This programme is essentially based on culling infected dogs from endemic regions. Thus, there is an urgent need to develop other control measures against VL to deter its advance. Here, a subunit vaccine, a recombinant vaccine, an insecticide-impregnated collar and the associations between these measures were evaluated for reducing the incidence of Leishmania infection in dogs. This was through a cohort study conducted in an endemic region of Brazil, considering the incidence and time of total exposure over a period of 1 year. The incidence of VL was estimated by means of serological and molecular diagnostic tests, 180 and 360 days after the application of the control measures. The estimates of the effectiveness (EF) were not significant in any cohort. The EF of the subunit vaccine, the recombinant vaccine and the collar were 26.4%, 32.8% and 57.7% and the upper limit of the 95% confidence interval for EF were 63.7%, 67.9% and 82.5%, respectively. In conclusion, under the conditions of this study, none of the immunogens for VL control was sufficiently effective to protect dogs against infection. On the other hand, use of collars impregnated with insecticide seems to constitute a method with better prognosis, corroborating other studies in this field.
The objective of this study was to evaluate the effects of the energy restriction of gestation of adult ewes from day 45 to day 115 on lamb live performance parameters, carcass and meat traits. In experiment I, dietary energy was restricted at 70% of the metabolizable energy (ME) requirements, after which ewes were re-fed ad libitum until lambing. In experiment II, dietary energy was restricted at 60% of the ME requirements, and ewes were re-fed to ME requirements until lambing. All ewes grazed together from the end of the restriction periods to weaning. Lambs were weaned and lot fed until slaughter. Feed intake, weight gain and feed efficiency were recorded, and body fat thickness and ribeye area (REA) were measured in the longissimus thoracis muscle. After slaughter, carcass weight and yield, fat depth, carcass and leg length, and frenched rack and leg weights and yields were determined. Muscle fiber type composition, Warner-Bratzler shear force, pH and color were determined in the longissimus lumborum muscle. In experiment I, energy restriction followed by ad libitum feeding affected lamb birth weight (P<0.05); however, no effects (P>0.05) were observed on later BW, REA, BF or carcass traits. Lambs born to non-restricted-fed ewes had higher (P<0.05) weight and yield of the frenched rack cut and their meat tended (P=0.11) to be tender compared with that of lambs from restricted ewes. The percentage of oxidative muscle fibers was lower for lambs born to non-restricted ewes (P<0.05); however, no effects of ewe treatment were observed on other muscle fiber types. For experiment II, energy restriction followed by ME requirements feeding, affected (P<0.01) pre-weaning live weight gain, weaning and final weights. Lambs from restricted ewes had higher (P<0.05) feed intake as % of leg weight and a trend to be less efficient (P=0.16) than lambs from unrestricted dams. Ribeye area and BF were not influenced by treatment. Treatment significantly affected slaughter weight, but had no effects on carcass yield and traits or on meat traits. The results obtained in both experiments indicate submitting ewes to energy restriction during gestation affects the performance of their progeny but the final outcome would depend on the ewe’s re-feeding level during late gestation and the capacity of the offspring to compensate the in utero restriction after birth.
Euthanasia of infected dogs is one of the measures adopted in Brazil to control visceral leishmaniasis (VL) in endemic areas. To detect infected dogs, animals are screened with the rapid test DPP® Visceral Canine Leishmaniasis for detection of antibodies against K26/K39 fusion antigens of amastigotes (DPP). DPP-positives are confirmed with an immunoenzymatic assay probing soluble antigens of promastigotes (ELISA), while DPP-negatives are considered free of infection. Here, 975 dogs from an endemic region were surveyed by using DPP, ELISA and real-time PCR (qPCR) for the diagnosis of VL. When DPP-negative dogs were tested by qPCR applied in blood and lymph node aspirates, 174/887 (19·6%) were positive in at least one sample. In a second sampling using 115 cases, the DPP-negative dogs were tested by qPCR in blood, lymph node and conjunctival swab samples, and 36/79 (45·6%) were positive in at least one sample. Low-to-moderate pairwise agreement was observed between all possible pair of tests. In conclusion, the official diagnosis of VL in dogs in Brazilian endemic areas failed to accuse an expressive number of infected animals and the impact of the low accuracy of serological tests in the success of euthanasia-based measure for VL control need to be assessed.
Zoonotic diseases are a significant health threat for humans and animals. To better understand the epidemiology, etiology, and pathology of infectious agents affecting humans and animals combined approaches are needed. Here we describe an epidemiological investigation conducted by physicians and veterinarians after a reported case of psittacosis. Upon admission suffering from respiratory distress syndrome in a hospital and with a history of bird contact, a female patient was serologically diagnosed with psittacosis. After the case notification, veterinarians were able to investigate the source of infection by detecting Chlamydia psittaci in her pet cockatiel. The bird was hospitalized and successfully treated. In addition, the establishment where the pet bird was purchased was traced and through molecular techniques other birds intended to be sold as pets tested positive for C. psittaci. As a result, sanitary measures were applied and the establishment then was closed down. The birds intended for the pet commerce were treated and retested with negative molecular results for C. psittaci, thus avoiding disease propagation. Reliable data about zoonotic diseases can only be generated through the application of multidisciplinary approaches which take into account the epidemiological factors and interactions of humans, animals and their environments as an integrated system.
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.
The rapid spread of glyphosate-resistant sourgrass populations generates concern in the agricultural production sector in Brazil. Nonetheless, there is not much information related to the frequency and dispersion of sourgrass throughout recent years. We investigated the frequency and dispersion of glyphosate-resistant sourgrass populations in Brazilian agricultural regions as part of a larger-scale weed resistance monitoring study. A discriminatory rate of 960 g ae ha−1 of glyphosate was used on plants at the 2- to 3-tiller stage, originating from 2,593 populations of sourgrass sampled in 329 counties in 14 Brazilian states between 2012 and 2015. The dispersion of sourgrass populations originated in western Paraná State, next to the Paraguay border, where the first resistance case was reported. Its dispersion to the central region of Brazil, mainly in soybean-producing areas, is most likely a consequence of agricultural equipment movement and wind-mediated dispersal. Glyphosate-resistant sourgrass populations were found in every geographical region across all Brazilian states tested. These data highlight the importance of an appropriate weed resistance monitoring program to track the evolution and dispersion of resistance to mitigate these issues by focusing efforts regionally and raising awareness among stakeholders in each region.
Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.
The Brazilian Twin Registry (BTR) was established in 2013 and has impelled twin research in South America. The main aim of the initiative was to create a resource that would be accessible to the Brazilian scientific community as well as international researchers interested in the investigation of the contribution of genetic and environmental factors in the development of common diseases, phenotypes, and human behavior traits. The BTR is a joint effort between academic and governmental institutions from Brazil and Australia. The collaboration includes the Federal University of Minas Gerais (UFMG) in Brazil, the University of Sydney and University of Melbourne in Australia, the Australian Twin Registry, as well as the research foundations CNPq and CAPES in Brazil. The BTR is a member of the International Network of Twin Registries. Recruitment strategies used to register twins have been through participation in a longitudinal study investigating genetic and environmental factors for low back pain occurrence, and from a variety of sources including media campaigns and social networking. Currently, 291 twins are registered in the BTR, with data on demographics, zygosity, anthropometrics, and health history having been collected from 151 twins using a standardized self-reported questionnaire. Future BTR plans include the registration of thousands of Brazilian twins identified from different sources and collaborate nationally and internationally with other research groups interested on twin studies.
Amazonian white-sand vegetation has unique tree communities tolerant to nutrient-poor soils of interest for interpreting processes of adaptation in neotropical forests. Part of this phytophysionomy is confined to Late Quaternary megafan palaeo-landforms, thus we posit that sedimentary disturbance is the main ecological factor controlling tree distribution and structuring in this environment. In this study, we characterize the topographic trend of one megafan palaeo-landform using a digital elevation model and verify its relationship to the forest by modelling the canopy height with remote sensing data. We also compare the composition and structure (i.e. canopy height and diameter at breast height) of tree groups from the outer and inner megafan environments based on the integration of remote sensing and floristic data. The latter consist of field inventories of trees ≥ 10 cm dbh using six (500 × 20 m) plots in várzea, terra firme and igapó from the outer megafan and 20 (50 × 20 m) plots in woodlands and forests from the inner megafan. The unweighted pair group method with arithmetic mean (UPGMA) and the non-metric multidimensional scaling (NMDS) were applied for clustering and dissimilarity analyses, respectively. The megafan is a sand-dominated triangular wetland with a topographic gradient of < 15 cm km−1, being more elevated along its axis. The outer megafan has a higher number of tree species (367), taller canopy height (mean of 14.1 m) and higher diameter at breast height (mean of 18.2 cm) than the white-sand forest. The latter records 89 tree species, mean canopy height of 8.4 cm and mean diameter at breast height of 15.3 cm. Trees increase in frequency closer to channels and toward the megafan's axis. The flooded and nutrient-poor sandy megafan substrate favoured the establishment of white-sand vegetation according to the overall megafan topography and morphological heterogeneities inherent to megafan sub-environments.
Wheat is an important crop in the highlands of Northern Ethiopia and climate change is expected to be a major threat to wheat productivity. However, the potential impacts of climate change and adaptation on wheat yield has not been documented for this region. Wheat field experiments were carried out during the 2011–2013 cropping seasons in Northern Ethiopia to: (1) calibrate and evaluate Agricultural Production Systems sIMulator (APSIM)-wheat model for exploring the impacts of climate change and adaptation on wheat yield; (2) explore the response of wheat cultivar/s to possible change in climate and carbon dioxide (CO2) under optimal and sub-optimal fertilizer application and (3) assess the impact of climate change and adaptation practices on wheat yield based on integration of surveyed field data with climate simulations using multi-global climate models (GCMs; for short- and mid-term periods) for the Hintalo-Wajrat areas of Northern Ethiopia. The treatments were two levels of fertilizer (optimal and zero fertilization); treatments were replicated three times and arranged in a randomized complete block design. All required information for model calibration and evaluation were gathered from experimental studies. In addition, a household survey was conducted in 2012 in Northern Ethiopia. Following model calibration and performance testing, response of wheat to various nitrogen (N) fertilizer rates, planting date, temperature and combinations of other climate variables and CO2 were assessed. Crop simulations were conducted with future climate scenarios using 20 different GCMs and compared with a baseline. In addition, simulations were carried out using climate data from five different GCM with and without climate change adaptation practices. The simulated yield showed clear responses to changes in temperature, N fertilizer and CO2. Regardless of choice of cultivar, increasing temperatures alone (by up to 5 °C compared with the baseline) resulted in reduced yield while the addition of other factors (optimal fertilizer with elevated CO2) resulted in increased yield. Considering optimal fertilizer (64 kg/ha N) as an adaptation practice, wheat yield in the short-term (2010–2039) and mid-term (2040–2069) may increase at least by 40%, compared with sub-optimal N levels. Assuming CO2 and present wheat management is unchanged, simulation results based on 20 GCMs showed that median wheat yields will reduce by 10% in the short term and by 11% in the mid-term relative to the baseline data, whereas under changed CO2 with present management, wheat yield will increase slightly, by up to 8% in the short term and by up to 11% in the mid-term period, respectively. Wheat yield will substantially increase, by more than 100%, when simulated based on combined use of optimal planting date and fertilizer applications. Increased temperature in future scenarios will cause yield to decline, whereas CO2 is expected to have positive impacts on wheat yield.
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.
This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT–PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50–83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome.