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91.
Costa LM Zahler-Rinder M Ribeiro MF Rembeck K Rabelo EM Pfister K Passos LM 《Veterinary parasitology》2012,188(1-2):160-163
This paper reports the development and use of a Real Time PCR for detection of Babesia canis canis, B. canis rossi, and B. canis vogeli in endemic areas of Brazil. The sequences of the internal transcribed spacer (ITS) of several organisms were aligned and five primers and four probes were designed for amplification of a fragment (around 125 bp) which differentiates subspecies of B. canis. Blood samples collected from dogs living in farms in three distinct rural regions within the State of Minas Gerais (Lavras, Belo Horizonte and Nanuque) were tested. Blood samples had been collected during a dry season (Lavras, n=100; Belo Horizonte, n=50; Nanuque, n=102); the dogs were re-sampled in the subsequent rainy season (Lavras, n=71; Belo Horizonte, n=29; Nanuque, n=66). From each sample, DNA was extracted and Giemsa stained smears were microscopically examined for direct detection of Babesia parasites. B. canis vogeli was the only subspecies found, with an overall prevalence of 9.9% during the dry season and 10.8% during the rainy season. Dogs living in Nanuque and Belo Horizonte showed significantly higher prevalence rates than those living in Lavras (13.7%, 12.0% and 5.0%, respectively). The Real Time PCR developed proved to be appropriate to detect B. canis subspecies in endemic areas. 相似文献
92.
93.
Ullmann LS Hoffmann JL de Moraes W Cubas ZS dos Santos LC da Silva RC Moreira N Guimaraes AM Camossi LG Langoni H Biondo AW 《Journal of zoo and wildlife medicine》2012,43(2):223-228
Leptospirosis is a bacterial zoonosis of worldwide distribution and is endemic in tropical countries, where rodents and other wild mammals are abundant and may act as reservoirs. Leptospirosis has become a concern in captive wild animals, due mostly to their exposure to contaminated urine or environment. Although domestic cats (Felis catus) have been reported refractory to leptospirosis, serology and disease in captive wild felids is still unclear. In this study 57 adult, clinically healthy felids, including 1 Geoffroy's cat (Leopardus geoffroyi), 3 jaguarundis (Puma yagouaroundi), 17 margays (Leopardus wiedii), 22 little spotted cats (Leopardus tigrinus), and 14 ocelots (Leopardus pardalis) kept in captivity at the Sanctuary at the Itaipu Binacional hydroelectric power plant (Bela Vista Biological Sanctuary), Foz do Iguacu City, Paraná State, Brazil, were serologically surveyed for the presence of antibodies against 28 serovars of Leptospira spp. by microagglutination test (MAT). Two animals (3.5%) were seropositive: one male ocelot to the serovar Cynopteri (titer 100) and one female margay to Autumnalis (100) and Butembo (200). The captive-born, 5-yr-old ocelot had been solitary housed in an individual cage. The approximately 21-yr-old wild-caught margay was also kept individually. None of the tested animals showed signs ofleptospirosis. During a study conducted 4 yr previously in the same facility, this particular margay also tested positive for the same two serovars, among others. The present study indicates that the felids tested for Leptospira spp. by MAT were exposed to serovars, but did not demonstrate clinical signs of disease. Comparison with a previous study suggests that serovar titers may vary over time and that leptospirosis dynamics remains unclear in wild felids. 相似文献
94.
Phuong-Y. Mai Graldine Le Goff Erwan Poupon Philippe Lopes Xavier Moppert Bernard Costa Mehdi A. Beniddir Jamal Ouazzani 《Marine drugs》2021,19(7)
Solid-phase extraction embedded dialysis (SPEED technology) is an innovative procedure developed to physically separate in-situ, during the cultivation, the mycelium of filament forming microorganisms, such as actinomycetes and fungi, and the XAD-16 resin used to trap the secreted specialized metabolites. SPEED consists of an external nylon cloth and an internal dialysis tube containing the XAD resin. The dialysis barrier selects the molecular weight of the trapped compounds, and prevents the aggregation of biomass or macromolecules on the XAD beads. The external nylon promotes the formation of a microbial biofilm, making SPEED a biofilm supported cultivation process. SPEED technology was applied to the marine Streptomyces albidoflavus 19-S21, isolated from a core of a submerged Kopara sampled at 20 m from the border of a saltwater pond. The chemical space of this strain was investigated effectively using a dereplication strategy based on molecular networking and in-depth chemical analysis. The results highlight the impact of culture support on the molecular profile of Streptomyces albidoflavus 19-S21 secondary metabolites. 相似文献
95.
96.
Luiz Fernando Costa e Silva Sebastião de Campos Valadares Filho Edenio Detmann Polyana Pizzi Rotta Diego Zanetti Faider Alberto Castaño Villadiego Samantha Gusmão Pellizzoni Rafael Moura Guimarães Pereira 《Tropical animal health and production》2013,45(3):795-803
The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259?±?25 kg and age of 14?±?1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P?<?0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P?>?0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P?>?0.05) by time spent in the feedlot. No differences were observed (P?>?0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which corresponds to 456 kg of EBW in Nellore bulls. Therefore, this study can conclude that the feedlot time period does not affect DMI, nutrient intake, ADG, or microbial efficiency. The equation proposed by BR CORTE (Azevêdo et al. 2010) correctly estimates the DMI of Nellore bulls, which reach maturity when an EBW of 456 kg is attained. 相似文献
97.
98.
A.A. Macedo E.A. Costa A.P.C. Silva T.A. Paixão R.L. Santos 《Veterinary immunology and immunopathology》2013,151(3-4):294-302
99.
Michel Anderson Almeida Colmanetti Allan Lopes Bacha Pedro Luis da Costa Aguiar Alves Rinaldo Cesar de Paula 《林业研究》2019,(2):537-543
In silvopasture system, the coexistence of eucalyptus seedlings with other species may result in growth reduction, especially during eucalyptus early development.Therefore, studies elucidating how forage species affect the eucalyptus growth can provide important information for their rational management aiming to obtain the maximum gain of the system. The aim of this work was to evaluate the effect of increasing densities of Urochloa brizantha cv.Marandu in the early development of Eucalyptus urograndis. An experiment was conducted in 20 L pots, in an open and semi-controlled area, during 90 days after planting of eucalyptus. A completely randomized design with four replications was used, in a 6 9 7 factorial system, meaning six evaluation periods and seven densities of U. brizantha: 0(control), 22, 33, 44, 67, 89 and111 plants m-2. Fortnightly, eucalyptus height, stem diameter and chlorophyll fluorescence(Fv/Fm) were evaluated. At the end of experimental period, the net assimilation rate, stomatal conductance and transpiration rate of eucalyptus plants were determined, in addition to the dry matter of eucalyptus(leaves and stem) and U. brizantha (leaves). In coexistence with 111 plants m-2, eucalyptus had reduction of 63.9% on total dry matter and 72.7% on leaf area, compared to the control. From the density of22 plants m-2, U. brizantha negatively interfere significantly the growth of E. urograndis. Up to 8 plants m-2 there are no reductions greater than 5% in eucalyptus height and stem diameter. 相似文献
100.
Adibe Luiz Abdalla Filho Paulo de Mello Tavares Lima Gabriel Zanuto Sakita Tairon Pannunzio Dias e Silva Wilian dos Santos da Costa Raquel Ghini Adibe Luiz Abdalla Marisa de Cssia Piccolo 《Grass and Forage Science》2019,74(4):670-677
Increased atmospheric carbon dioxide (CO2) is a consequence of recent anthropogenic environmental changes, and few studies have evaluated its effects on tropical grasses used in Brazilian pastures, the main feed source for major part of ruminant livestock. This study evaluated forage production, chemical composition, in vitro total gas production and organic matter degradability of Brachiaria brizantha under contrasting CO2 atmospheric conditions in a free air carbon dioxide enrichment (FACE) facility. The forage plants were sown in each of the 12 octagonal rings of the FACE facility: six under ambient atmospheric CO2 concentration of approximately 390 μmol/mol, hereafter referred to as control (CON) plots, and other six rings enriched with pure CO2 flux to achieve a target CO2 concentration of 550 μmol/mol, hereafter called elevated CO2 (eCO2) plots. Soil samples were collected to determine carbon and nitrogen concentrations. After seventy days of sowing, a standardization cutting was performed and then at regular intervals of 21 days the forage was harvested (ten harvest dates) and forwarded to laboratorial analyses. Forage above‐ground biomass production (dry matter (DM): 6,143 vs. 6,554 kg/ha), as well as morphological characteristics (leaves: 71% vs. 68%; stem: 28% vs. 31%), chemical composition (crude protein: 162.9 vs. 161.8; neutral detergent fibre: 663.8 vs. 664.3; acid detergent fibre: 369.5 vs. 381; lignin: 60.1 vs. 64.1 g/kg DM; total C: 45.9 vs. 45.9; total N: 2.8 vs. 2.8; total S: 0.2% vs. 0.2%), organic matter in vitro degradability (573.5 vs. 585.3 g/kg), methane (5.7 vs. 4.3 ml/g DM) and total gas (128.3 vs. 94.5 ml/g DM) production did not differ significantly between CON and eCO2 treatments (p > .05). The results indicated that at least under short‐term enrichment, B. brizantha was not affected by eCO2. 相似文献