Evaluation of miltefosine for the treatment of dogs naturally infected with L. infantum (=L. chagasi) in Brazil

Dogs naturally infected with Leishmania Infantum (=L. chagasi) were treated with miltefosine using different therapeutic regimens. The animals were evaluated for clinical evolution, biochemical parameters, parasite load (by real-time PCR), cytokine levels and humoral response. After treatment and during the following 24 months, there was progressive clinical improvement and complete recovery in 50% (7/14) of the treated animals. There was a decrease in the smear positivity of the bone marrow after treatment, and there was also a gradual and constant decrease in positive cultures at the end of the follow-up period. However, the PCR detection of parasite DNA remained positive. In general, all animals presented a significant increase in parasite load 6 months after treatment. The IFN-γ levels in all the groups tended to increase during follow-up period, regardless of the miltefosine dose administered. The IL-4 and IL-10 levels of the animals tended to decrease during follow-up, except after 300 days when only IL-10 increased. The serum antibodies identified antigens that ranged from 116 kDa to less than 29 kDa in the Western blot assay. Furthermore, 300 days after treatment, qualitative and quantitative differences in the antigen profiles were observed. Antigens of 97 and 46 kDa were the most intensely recognized. Higher levels of antigen-specific Leishmania IgG were detected before and 300 days after treatment in all groups. Taking together, the improvement in the clinical symptoms was not followed by parasitological clearance, suggesting that treatment with miltefosine is not recommended, especially in endemic areas like Brazil, where children are the major victims and dogs are involved in the maintenance of the parasite cycle.     

Genetic analysis of Anisakis typica (Nematoda: Anisakidae) from cetaceans of the northeast coast of Brazil: new data on its definitive hosts

Prevalence and seasonal variations of helminth infections and their association with morbidity parameters were studied in traditionally reared Cambodian cattle. Four villages in two provinces of West Cambodia were visited on monthly intervals over a period of 11 months, during which 2391 animals were faecal and blood sampled for parasitological and haematological examinations. The body condition score (BCS), faecal consistency (diarrhoea score, DS), colour of the ocular conjunctivae (FAMACHA(?)) and packed cell volume were determined for each individual animal. The overall proportion of samples that was positive for gastrointestinal nematodes was 52%, 44% and 37% in calves (from 1 to 6 months), young animals (6 to 24 months) and adults (over 24 months), respectively, while geometric mean faecal egg counts (FECs) for each of these age categories were 125, 66 and 15 eggs per gram, respectively. Six genera of strongyles were found in the faecal cultures, i.e. in descending order of occurrence, Cooperia, Oesophagostomum, Haemonchus, Trichostrongylus, Mecistocirrus and Bunostomum. The prevalences of Fasciola and Paramphistomum, estimated by coprological examination, varied between 5-20% and 45-95%, respectively. Logistic mixed models were used to investigate associations of morbidity markers with the presence of parasite infection. A low BCS was associated with gastrointestinal nematode and liver fluke infections, and soft faecal consistency with Paramphistomum infections. However, other factors such as nutritional deficiencies and intercurrent diseases are likely to enhance the effects of parasites and should therefore be considered when using these morbidity parameters as indicators of parasitism.     

Synthetic genetic polymers capable of heredity and evolution

Genetic information storage and processing rely on just two polymers, DNA and RNA, yet whether their role reflects evolutionary history or fundamental functional constraints is currently unknown. With the use of polymerase evolution and design, we show that genetic information can be stored in and recovered from six alternative genetic polymers based on simple nucleic acid architectures not found in nature [xeno-nucleic acids (XNAs)]. We also select XNA aptamers, which bind their targets with high affinity and specificity, demonstrating that beyond heredity, specific XNAs have the capacity for Darwinian evolution and folding into defined structures. Thus, heredity and evolution, two hallmarks of life, are not limited to DNA and RNA but are likely to be emergent properties of polymers capable of information storage.     

Serologic survey of brucellosis in captive neotropical wild carnivores in northeast Brazil

Abstract. This study reports the detection of antibodies against Brucella abortus and B. canis in wild neotropical carnivores kept in captivity in three zoos in northeastern Brazil. A total of 42 serum samples were examined, 17 from coatis (Nasua nasua), eight from crab-eating raccoons (Procyon cancrivorus), three from crab-eating foxes (Cerdocyon thous), three from hoary foxes (Lycalopex vetulus), two from little spotted cats (Leopardus tigrinus), five from tayras (Eira barbara), two from greater grisons (Galictis vittata), and two from neotropical river otters (Lontra longicaudis). The Rose-Bengal test and complement fixation test (CFT) were performed to detect anti-Brucella spp. antibodies, whereas the agar gel immunodiffusion test (AGID) was employed to detect anti-B. canis antibodies. The overall seroprevalence varied by species and by test; in addition, CFT and AGID seemed better able to detect antibodies against B. abortus and B. canis, respectively. This is the first study on the presence of anti-Brucella spp. antibodies in captive carnivores from Brazil, as well as the first report of antibodies to Brucella spp. in coatis, crab-eating raccoons, hoary foxes, little spotted cats, tayras, and greater grisons.     

Nonlinear regression for description of strawberry (Fragaria x ananassa) production

The aim of this study was to select growth models to describe strawberry (Fragaria x ananassa)fruit production. To do this, data on 16 treatments (combination of 2 cultivars [Albion and Camarosa], 2 origins [National and Imported], and 4 organic substrates mixed [70% crushed sugar cane residue + 30% organic compost, 70% crushed sugar cane residue + 30% commercial substrate, 70% burnt rice husk + 30% organic compost, and 70% burnt rice husk + 30% commercial substrate]) conducted in a Randomized Complete Block Design (RCBD) with 4 replicates were used. Different parameterizations of the Logistic, Gompertz, and von Bertalanffy models were adjusted for number and weight of fruits per plant (g) accumulated in multiple harvests. The model adjustment and parameter estimation were obtained by ordinary least squares, using a Gauss Newton algorithm. The selection of the best model was chosen by intrinsic and parametric nonlinearity. Among the adjusted nonlinear models, the best adjustment for both variables was achieved by the parameterization 2 of the Logistic model and parameterization 1 of the Gompertz model, because they had lower results with less parametric and intrinsic nonlinearity. However, care should be taken when using the Gompertz model because it tends to overestimate the production estimate and may cause misunderstandings in interpretation.     

Effects of aflatoxin B 1 on performance and health of tambaqui fingerlings ( Colossoma macropomum )

The detection of mycotoxins in feeds and their ingredients in aquaculture gained prominence due to losses caused in production and animal health, mainly the occurrence of aflatoxin (AFB1). The aim of this study was to evaluate the effects of AFB1 on the performance of tambaqui fingerlings (Colossoma macropomum). Four hundred tambaqui were used. Four different treatments were evaluated: treatment T1, considered as the control treatment (CT) with 3.84 μg kg−1; treatment T2, treatment T3 and treatment T4 with 500, 1000 and 2000 μg kg−1 of AFB1, respectively. The AFB1 of the samples (muscle, liver and kidney) was detected by high-pressure liquid chromatography. Four fingerlings from each treatment for histological analysis were examined. Moreover, the performance parameters (weight gain, feed conversion and feed intake) were studied. The levels of toxins used in T2, T3 and T4 represent a reduction in the growth of 14%, 35% and 45%, respectively. The T3 and T4 showed the lowest weight gain (78%) and the worst feed conversion. Aflatoxin B1 in muscle (3.28 μg kg−1) and kidneys (8.8 μg kg−1) in the T3, as well as liver (4.4 μg kg−1) and kidney (4.08 μg kg−1) in T4, was detected. Histopathological changes in liver and kidney tissues of fingerlings were more pronounced in T3 and T4. Fingerlings that consume feed contaminated with AFB1 in concentrations higher than 500 μg kg−1 present decreases in growth, reduction in weight gain and feed intake with increased feed conversion. The consumption of feed contaminated with 1000 and 2000 μg kg−1 of AFB1 caused severe deterioration in the hepatic and renal tissues.     

Tributaries as biodiversity preserves: An ichthyoplankton perspective from the severely impounded Upper Paraná River

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Detection of RHDV strains in the Iberian hare (Lepus granatensis): earliest evidence of rabbit lagovirus cross-species infection

Rabbit hemorrhagic disease virus (RHDV) is a highly lethal Lagovirus, family Caliciviridae, that threatens European rabbits (Oryctolagus cuniculus). Although a related virus severely affects hares, cross-species infection was only recently described for new variant RHDV in Cape hares (Lepus capensis mediterraneus). We sequenced two strains from dead Iberian hares (Lepus granatensis) collected in the 1990s in Portugal. Clinical signs were compatible with a Lagovirus infection. Phylogenetic analysis of the complete capsid gene positioned them in the RHDV genogroup that circulated on the Iberian Peninsula at that time. This is the earliest evidence of RHDV affecting a species other than European rabbits.     

Response of Passiflora setacea to Mycorrhization and Phosphate Fertilization in a Semiarid Region of Brazil

The Caatinga is a unique biome that encompasses nearly 11% of Brazil's territory and contains diverse vegetation composed of trees and bushes that have been scarcely studied from the economic perspective. In this context, Passiflora setacea may constitute a strategic alternative for agriculture because it produces fruit that has commercial potential and is tolerant to some diseases. Some species of Passiflora show more robust growth when associated with arbuscular mycorrhizal fungi (AMF) and are dependent on mycorrhization. In this study, the response of P. setacea to phosphate (P) fertilization and mycorrhization with Claroideoglomus etunicatum was evaluated. The experimental design included eight replicates of four randomized treatments: non-inoculated plants (NI), plants fertilized with phosphorus (P), mycorrhized plants (AMF), and plants that were both fertilized and mycorrhized (P+AMF). The plant height, leaf number, leaf area, fresh biomass (FB), and dry biomass (DB) of the shoots and roots, nutrient content, mycorrhizal colonization (MC), and the number of glomerospores (NG) in the rhizosphere were evaluated. The MC and the NG were reduced by phosphate fertilization. The development of the mycorrhized plants was significantly better than the NI and P treated plants for all of the variables tested. Inoculation with C. etunicatum promoted the growth of P. setacea seedlings even in the absence of phosphate fertilization, reducing production costs and strengthening the potential of P. setacea as a viable agricultural alternative for the semiarid region.     

Inclusion of β-1,3/1,6-glucan in the ornamental fish,Jewel tetra (Hyphessobrycon eques), and its effects on growth,blood glucose,and intestinal histology

The effects of β-1,3/1,6-glucan on Hyphessobrycon eques were assessed after 42 days of feeding diets containing 0 (control group given commercial feed), 0.5, 1, or 2 g β-glucan/kg diet. In total, 180 fish, with an initial weight of 0.43?±?0.03 g, were used. There were 15 fish in each of twelve 42-L aquariums, and there were 3 aquariums of fish for each dietary treatment. The fish were fed until apparent satiety. Performance parameters (final weight, total length, standard length, feed intake, survival rate, weight gain, feed conversion, specific growth rate, and condition factor) and plasma glucose concentration were measured. Histological analysis of the proximal portion of the intestine (width and height of the villi, depth of the crypts, height of the enterocytes, thickness of the muscle layer, and number of goblet cells) was performed. Different levels of the additive did not influence fish performance (for example, final weight: control: 0.63 g, 0.5: 0.60, 1: 0.58, and 2: 0.61). Likewise, there was no influence on the plasma glucose concentration (control: 81.80 mg/dL, 0.5: 75.33, 1: 85.00, and 2: 81.00) and intestinal morphometry of the animals. However, the results showed that 2.0 g/kg of β-1,3/1,6-glucan provided a greater abundance of goblet cells secreting acidic and neutral mucus present in the epithelium (periodic acid-Schiff: 66.67 cells, Alcian blue pH 1.0: 72,67 cells, and Alcian blue pH 2.5: 95.00 cells), showing significant differences when compared to animals in the control group, which may represent better protection of the intestinal epithelium of H. eques.