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71.
Armando de Mattos Carvalho Ana Liz Garcia Alves Patrícia Galvão Gomes de Oliveira Luis Emiliano Cisneros Álvarez Renée Laufer Amorim Carlos Alberto Hussni Elenice Deffune 《Journal of Equine Veterinary Science》2011,31(1):26-34
Superficial digital flexor tendon lesion is an important cause of lameness in equine athletes. Although numerous treatments have been described, few are effective at promoting significant improvement in the quality of the extracellular matrix. Therefore, great potential remains for recurrence and in certain cases, an abrupt end to the horse’s athletic career. Recently, several experiments have focused on the therapeutic potential of mesenchymal stem cells (MSCs) in cases of tendon lesions. This study aimed to evaluate the effect of adipose tissue-derived MSCs in the treatment of induced tendinitis of the superficial digital flexor tendon in horses by clinical, ultrasonographic, histopathological, and immunochemical analyses. Tendinitis was induced in both thoracic limbs of eight mares by administration of collagenase solution and adipose tissue was collected from the tail base for MSCs isolation and expansion, which were used during cellular therapy on only one limb 30 days after lesion induction. No differences occurred between the groups regarding the clinical and ultrasonographic analyses; however, histopathological evaluation revealed a significant improvement in tendon fiber organization and diminished inflammatory infiltrate, whereas immunohistochemical analysis showed increased expression of type I collagen in the treated group as compared with controls. The cellular therapy model implanted in this experiment promoted increased perivascular inflammatory infiltrate, fibroblastic density, neovascularization, and qualitative healing improvement of tendon extracellular matrix, in terms of fiber orientation and type I/III collagen ratio; moreover, it was considered to be a safe and viable process. 相似文献
72.
Luiza de S. Seixas Cristiano Barros de Melo Rômulo C. Leite Élvio C. Moreira Concepta M. McManus Márcio B. de Castro 《Tropical animal health and production》2011,43(1):9-11
To define the prevalence of anti-Leptospira sp. agglutinins in ewes in the Federal District, Brazil, serum samples from 157 ewes were tested for antibodies against serovars
of Leptospira sp. by the microscopic agglutination test. Antibodies were detected in three flocks in a prevalence of 3% (95% CI = 0.4%–5.7%).
Considering that sheep and cattle were raised together, the lack of sanitary control could represent a risk to cattle production,
which is the most important activity in the Centre-West region of Brazil. 相似文献
73.
Tritrichomonas mobilensis is an intestinal parasite of squirrel monkeys. There are few reports concerning the morphological aspects of this parasite. In addition, the taxonomic relationship between T. mobilensis and Tritrichomonas foetus, a serious pathogen that causes bovine and feline trichomonosis, has been questioned. For this reason, in the present study, we examined and compared both tritrichomonads with regard to their morphology, ultrastructure, endocytic activity and cytotoxicity when in the presence of host cells. Electron microscopy demonstrated consistent morphological differences between the hydrogenosomes of both parasites. Moreover, T. mobilensis and T. foetus had striking differences in their endocytic behavior. Thus, this work provides additional data that support the hypothesis that T. mobilensis is a distinct species from T. foetus. 相似文献
74.
D. Mattos Jr. J. A. Quaggio H. Cantarella A. K. Alva D. A. Graetz 《Journal of plant nutrition》2013,36(8):1371-1385
The majority of the citriculture in Brazil is located in the state of São Paulo, with a total production area of 700,000 ha. Trees are grafted mostly on ‘Rangpur’ lime (RL; Citrus limonia Osbeck) rootstock. Despite its good horticultural performance, use of other rootstocks has increased with the search for disease-tolerant varieties to improve grove productivity and longevity. Furthermore, there is a lack of information on young tree response to fertilization, and optimal nutrient requirements of different scion/rootstock combinations for maximum fruit yield. A network of field experiments was conducted to study the differential response of young sweet orange trees on selected rootstocks to nitrogen (N), phosphorus (P), and potassium (K) fertilization. The application of soil and leaf analyses to develop optimal fertilizer recommendations was evaluated. Experiments were conducted in three locations using fractional factorial design of one-half (4 × 4 × 4) type with four rates of N, P, or K calculated to be applied for five years after tree planting. Fruit yield response was evaluated during the last two years and correlated with soil and leaf analyses data. The trees on RL rootstock demonstrated increased efficiency of nutrient use and fruit production compared with those on ‘Cleopatra’ mandarin (CL; C. reshni hort. ex Tanaka) or ‘Swingle’ citrumelo [SW; Poncirus trifoliata (L.) Raf. × C. × paradisi Macfad.] rootstocks. The trees on SW rootstock appeared to require greater N and K rates than those on RL rootstock. Phosphorus requirement was greater for ‘Natal’ or ‘Valencia’ trees on CL than on RL rootstock. These results will become the basis for revising current fertilizer recommendation guidelines for young trees in Brazil. 相似文献
75.
A.M. Felício L.G. Gaya J.B.S. Ferraz C.T. Moncau E.C. Mattos N.P. Santos T. Michelan Filho J.C.C. Balieiro J.P. Eler 《Livestock Science》2013,157(1):81-87
Broiler feed efficiency and meat quality are the primary factors considered by the poultry industry. This study was conducted to estimate heritability and genetic correlation coefficients for skeletal muscle fiber number, area and diameter and performance and meat quality traits of Pectoralis major in a single male broiler line. (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. The numerator relationship matrix was composed by 77,474 individuals. Heritability coefficient estimates ranged from moderate to high for juvenile BW, breast weight, ultrasound record of pectoral muscle, lightness and thawing meat loss. Genetic correlation estimates for performance and skeletal muscle fiber traits indicated that selection for higher breast weight and juvenile BW could reduce muscle fiber number and increase muscle fiber diameter and area, which could prejudice the meat quality of this line. Selection for muscle fiber number and against muscle fiber diameter and area might improve meat water retention ability and tenderness in this broiler line, and selection programs could consider those traits as selection criteria, although this may be costly. We recommend the evaluation of the indirect selection caused by the use of the performance traits as selection criteria especially for juvenile BW and breast weight. Direct, intense selection for both traits might be unfavorable for most of the meat quality traits analyzed, which could lead to losses to both the chicken meat processing industry and consumers. 相似文献
76.
Esdras Henrique da Silva Vanessa da Silva Mattos Cleber Furlaneto Marc Giband Paulo Augusto Vianna Barroso Antônio Williams Moita Aldemiro Jorge-Junior Valdir Ribeiro Correa Philippe Castagnone-Sereno Regina Maria Dechechi Gomes Carneiro 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(1):195-204
The root-knot nematode Meloidogyne incognita is widely distributed and a major pathogen of cotton (Gossypium spp.) worldwide. The objectives of this study were to assess the genetic variability and aggressiveness of Brazilian populations of M. incognita in cotton. Five populations of M. incognita and one isolate of M. enterolobii (outgroup) were used in the molecular analysis. Our results showed that only 2.7 % of the RAPD and AFLP fragments were polymorphic. Despite the existence of two races (races 3 and 4) and two esterase phenotypes (I1 and I2), a low genetic variability among populations was observed, which might be due to the mitotic parthenogenetic mode of reproduction of this pathogen. The aggressiveness/virulence among populations towards different cotton genotypes was also studied. None of the populations was virulent to the resistant cotton genotypes M-315 RNR, TX-25, CIR1343, Wild Mexican Jack Jones and CIR1348 (reproduction factor <1). Two populations of M. incognita from the states of Mato Grosso do Sul and Parana (Umuarama) (races 4 and 3, respectively) were highly aggressive to the susceptible control FM966 and virulent to the accessions LA-887 and Clevewilt-6 that showed moderate resistance to other populations tested. 相似文献
77.
Belle Cristiano Kaspary Tiago Edu Groth Mártin Zanchett Cocco Kassia Luiza Teixeira 《植物病害和植物保护杂志》2017,124(4):393-397
Journal of Plant Diseases and Protection - Samples of melon plants with aerial symptoms that represented yellowing of leaves and stunting, and below-ground galls on the roots from two growing areas... 相似文献
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C. A. Alvares P. C. Sentelhas E. M. Mattos A. C. Miranda W. B. Moraes P. H.M. Silva E. L. Furtado J. L. Stape 《Forest Pathology》2017,47(1)
Brazilian forest‐based industries are supported by more than 5.5 million hectares of Eucalyptus growing under different climatic conditions with different degrees of favourability for rust Puccinia psidii, including both traditional and expanding areas, where such disease is of major concern for the industry, foresters and scientists. The main objective of this study was to define favourable climatic zones for Eucalyptus rust in Brazil with the following aims: (i) to develop a spatial method for estimating the mean night‐time temperature (Tng); (ii) to assess and validate a Eucalyptus rust model; and (iii) to map Eucalyptus rust favourability zones in Brazil based on the proposed model. A straightforward method, based only on latitude, day of the year, maximum and minimum air temperatures, was developed to estimate Tng, which is a key variable for a proper application of Ruiz rust model. Based on 37 field experiments with natural rust occurrence, it was observed that climatic conditions are determining factors for disease severity. Significant correlations between disease severity observed in the field and climatic conditions were found: a negative correlation with temperature (r = .50, p < .01) and a positive correlation with relative humidity (r = .89, p < .0001). A significant correlation (r = .81, p < .0001) between the normalized infection index, produced from Ruiz model, and the average rust score was also observed. Once the model was validated under field conditions, it was applied using historical average data of air temperature and leaf wetness duration to obtain monthly Eucalyptus rust favourability maps for the whole country. These final maps show that favourable climatic zones for Eucalyptus rust are extremely dynamic, with high temporal and spatial variability in Brazil and that climatic conditions should be considered for expansion of Eucalyptus to new areas, in breeding programmes, and for defining the most suitable seasons for forest establishment in each climate of the country. These results provide forestry managers with practical tools to reduce uncertainty about the expected severity of Eucalyptus rust in Brazil. 相似文献