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131.
Cortinhas Cristina Simões Botaro Bruno Garcia de Macedo Susana Nori dos Santos Marcos Veiga 《Tropical animal health and production》2018,50(7):1605-1610
Tropical Animal Health and Production - This study identified the association of management practices and herd characteristics with milk quality of bulk tanks in southeastern, Brazil. Milk samples... 相似文献
132.
Elizabeth Regina Carvalho Roberto Andrés Navarrete Ampuero Giovana Laís Ruviaro Tuleski Aparecido Antonio Camacho Marlos Gonçalves Sousa 《Veterinary research communications》2018,42(2):153-160
Ventricular arrhythmias (VA) are a recognized concern in dogs with degenerative mitral valve disease (DMVD). The coupling interval (CI) and the prematurity index (PI) have been shown to accurately differentiate between benign and malignant VA in people, where ventricular arrhythmias are known to be associated with an increased risk of development of signs of heart failure or sudden death. In this study, we characterized ventricular arrhythmias in dogs with symptomatic and asymptomatic DMVD. Seventy dogs with naturally-occurring DMVD and ventricular arrhythmias were retrospectively studied. A cross-sectional investigation including dogs with either symptomatic (stages C/D; n?=?41) or asymptomatic (stages B1/B2; n?=?29) DMVD was performed. Electrocardiographic tracings were reviewed to calculate both the CI and PI. In eight dogs these indices were compared with those obtained from both a Holter recording and a standard ECG tracing and no statistical differences were found (CI, p?=?0.97; PI, p?=?0.17). Even though CI and PI were determined in all animals enrolled in the study, VPC characteristics were only compared between symptomatic and asymptomatic dogs when a 24-h Holter recording was available (n?=?49). The PI was different (p?=?0.01) between symptomatic (0.65?±?0.17) and asymptomatic (0.56?±?0.18) dogs, but CI was considered similar (p?=?0.91). Also, the symptomatic dogs had more polymorphic VPC (p?=?0.002) and supraventricular arrhythmias (p?=?0.0002) than the asymptomatic animals. Polymorphism, and repeating patterns of ventricular premature complexes, were characteristics frequently present in overtly symptomatic animals affected by mitral endocardiosis. 相似文献
133.
134.
Unraveling avian and reptilian hematology: An optical and electron microscopic study of the buffy coat
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Filipe Fontes Pinto Célia Lopes Fernanda Malhão Ricardo Marcos 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(3):407-414
Background
Blood centrifugation and buffy coats are at the cornerstone of hematology. In mammals, the buffy coat has a layered disposition (from bottom to top) with neutrophils on top of erythrocytes, followed by monocytes/lymphocytes, and platelets. In nonmammals, this distribution is unknown. Recently, the cell tube block (CTB) technique was developed to study the buffy coat, but it was never applied to nonmammal buffy coats.Objectives
This study aimed to evaluate using the CTB technique to study reptilian and avian buffy coats and to propose its use for clinical applications.Methods
Blood from five birds and eight reptiles of different species was obtained to make CTBs that were processed for optical/electron microscopy. H&E, Sirius red, and immunohistochemistry staining against CD3 (to label T lymphocytes) were applied to the CTBs.Results
In birds, the buffy coat had a layered appearance with the granulocyte layer containing granulocytes (heterophils and eosinophils) and nucleated erythrocytes followed by a mononuclear cell layer containing lymphocytes, monocytes, and thrombocytes. In some animals, a nucleated erythrocyte layer was observed admixed with the granulocyte/mononuclear cell layer. A small clot within the buffy coat was seen in seven reptiles, and less definition of layers occurred in reptiles, with only one or two layers. Lymphocytes appeared toward the top of the buffy coat.Conclusions
From a comparative hematology perspective, the buffy coat of mammals differs from that of birds and more from that of reptiles. The CTB technique can be used to study these differences in avian and reptilian hematology, especially to study atypical circulating cells, hemoparasites, or blood cell proportions in health and disease. 相似文献135.
136.
Microclimate in agroforestry systems in central Amazonia: does canopy closure matter to soil organisms? 总被引:7,自引:0,他引:7
Christopher Martius Hubert Höfer Marcos V.B. Garcia Jörg Römbke Bernhard Förster Werner Hanagarth 《Agroforestry Systems》2004,60(3):291-304
Microclimate was recorded and soil organisms were collected 1997-1999 in ecosystem stands of contrasting structure in central
Amazonia (a primary forest, a 12-year secondary forest, two different agroforestry systems, a rubber tree (Hevea brasiliensis) plantation, and a peach palm (Bactris gasipaes) monoculture with a densely closed canopy). The aim was to look at the effects of canopy closure on microclimate and soil
organisms. Monthly maxima temperature, average air and soil temperatures, and saturation deficit were highest in September
1997, and total annual rainfall in 1997 was 12-28% lower than in the other study years. The monthly average litter temperatures
were consistently 2-4 °C higher in the plantation sites than in the rainforest and the secondary forest, and temperatures
on single days (not the monthly averages) in the plantations were up to 10 °C higher than in the primary forest. The highest
average litter and soil temperatures and the highest temperature maxima were recorded in the agroforestry plantations. Canopy
closure strongly determined the litter temperatures in the sites. Soil macrofauna biomass was also strongly correlated to
canopy closure (linear regression, P = 0.05). We conclude that a well developed canopy effectively protects the soil macrofauna
from high temperature variation and drought stress. Therefore, optimizing these agroforestry systems for canopy closure may
contribute to a better management of the beneficial soil decomposer community.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
137.
G. Moreno Marcos J. J. Obrador E. García E. Cubera M. J. Montero F. Pulido C. Dupraz 《Agroforestry Systems》2007,70(1):25-40
Dehesas are extant multi-purpose agroforestry systems that consist of a mosaic of widely-spaced scattered oaks (Quercus ilex L.) combined with crops, pasture or shrubs. We aimed to clarify the role of trees in dehesas of CW Spain focussed on the
analysis of tree-understorey interactions. Spatial variability of resources (light, soil moisture and fertility), microclimate,
fine roots of both herbaceous plants and trees and forage yield was measured. Additionally, we compared the nutritional and
physiological status, growth and acorn production of oaks in cropped (fodder crop), grazed (native grasses) and encroached
(woody understorey) dehesa plots. Significant light interception by trees was limited to the close vicinity of the trees,
with very low reduction away from them. Both microclimate and soil fertility improved significantly in the trees vicinity,
irrespective of soil management. Soil moisture varied very few with distance from the trees, as a result of the extended root
system of oaks. Root systems of trees and herbs did not overlap to a great extent. Crop production was higher beneath trees
than beyond the trees in unfertilised plots and foliar nutrient content of oaks did not increase significantly with crop fertilisation,
indicating that trees and crops hardly compete for nutrients. Moreover, trees benefited from the crop or pasture management:
trees featured a significantly improved nutritional and physiological status, a faster growth and a higher fruit productivity
than trees growing in encroached or forest plots. 相似文献
138.
Manuel Fernández Celia Marcos Raúl Tapias Federico Ruiz Gustavo López 《Annals of Forest Science》2007,64(8):865-873
Eucalyptus globulus is widely used in productive exotic plantations but the expansion of these plantations is limited by low temperatures, as its cold hardening capacity is limited (0.5 to 3.0 °C). It is not well understood how nursery fertilisation affects the field performance of plants. This led us to study the effect of three mineral nutrients (N, P and K) on both plant quality and frost tolerance. The experiment comprised eight growth treatments in which a high dose (H-) or a low dose (L-) of each nutrient was applied. Nitrogen was the nutrient that determined shoot growth, new root growth after transplanting (root egress), frost tolerance and field performance. Performance was better with treatment H-N than with treatment L-N, leaf nitrogen contents being 1.53 and 0.89% respectively. The effects of phosphorus and potassium were not significant between treatments for any parameter. The exception was P which, when interacting with N, favoured root egress for the H-N treatment. It was concluded that nursery fertilisation offers a management tool for eucalyptus growers concerned with plant stock quality. 相似文献
139.
de Souza PP Siebald HG Augusti DV Neto WB Amorim VM Catharino RR Eberlin MN Augusti R 《Journal of agricultural and food chemistry》2007,55(6):2094-2102
We have investigated the capability of direct infusion electrospray ionization mass spectrometry in the negative ion mode, ESI(-)-MS, to differentiate representative samples of artisan cacha?a, a Brazilian sugar cane distillate of large production, aged in four different types of wood casks: amburana (Amburana cearensis), jequitibA (Cariniana estrellensis), balm (Myroxylon peruiferum), and oak (Quercus rubra). The ESI(-)-MS were found to be very characteristic, showing sets of diagnostic ions for each of the four types of samples: amburana (m/z 271, 313, 377), jequitibA (m/z 143, 171, 255), balm (m/z 137, 269, 283, 297), and oak (m/z 197, 301, 307). Furthermore, principal component (PCA) and hierarchical cluster analysis (HCA), applied to the ESI(-)-MS data, divided these samples into four definite categories. The influence of the aging time on the ESI(-)-MS fingerprints of the cacha?a samples stored in oak casks was also established. An inversion in the relative intensity of the diagnostic ions of m/z 307 and 301 is detected in the ESI(-)-MS as the aging time increased from 1 to 2 years. The chemical structures of the major cacha?a components were proposed on the basis of the following: (a) the comparison of the ESI(-)-MS/MS of the diagnostic anions with those of the authentic anions or (b) the interpretation of the fragmentation patterns of the previously unknown diagnostic anions. Hence, direct infusion ESI(-)-MS allows not only a rapid, simple, and accurate way to distinguish among cacha?a samples stored in different wood casks but also monitoring changes in their chemical composition according to the aging time. 相似文献
140.
Canine visceral leishmaniasis (CL) is a zoonosis and a chronic systemic disease characterized by a wide spectrum of clinical signs, including, in rare occasions, polyarthritis. This report describes a case of CL in an 8-month old male boxer dog with a history of lameness, fever and lymphadenopathy. A definitive diagnosis of CL was based on the observation of the Leishmania amastigotes seen concomitantly, and for the first time, in the lymph nodes aspiration smears (in macrophages), synovial fluid (in macrophages and neutrophils) and blood (in neutrophils). Despite this extensive dissemination of the parasite, the animal was successfully treated with a multi-step combination of meglumine antimoniate, aminosidine and allopurinol. 相似文献