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排序方式: 共有391条查询结果,搜索用时 906 毫秒
381.
Jenevaldo B. Silva Gisele M. Fagundes João P.G. Soares Adivaldo H. Fonseca James P. Muir 《Tropical animal health and production》2014,46(7):1287-1295
Health and production management strategies influence environmental impacts of dairies. The objective of this paper was to measure risk factors on health and production parameters on six organic and conventional bovine, caprine, and ovine dairy herds in southeastern Brazil over six consecutive years (2006–2011). The organic operations had lower milk production per animal (P?≤?0.05), lower calf mortality (P?≤?0.05), less incidence of mastitis (P?≤?0.05), fewer rates of spontaneous abortions (P?≤?0.05), and reduced ectoparasite loads (P?≤?0.05) compared to conventional herds and flocks. Organic herds, however, had greater prevalence of internal parasitism (P?≤?0.05) than conventional herds. In all management systems, calves, kids, and lambs had greater oocyte counts than adults. However, calves in the organic group showed lower prevalence of coccidiosis. In addition, animals in the organic system exhibited lower parasitic resistance to anthelmintics. Herd genetic potential, nutritive value of forage, feed intake, and pasture parasite loads, however, may have influenced productive and health parameters. Thus, although conventional herds showed greater milk production and less disease prevalence, future research might quantify the potential implications of these unreported factors. 相似文献
382.
Jenevaldo Barbosa da Silva Charles Passos Rangel Adivaldo Henrique da Fonseca Eziquiel de Morais Wagner Marcelo Souza Vinhote Danillo Henrique da Silva Lima Natália da Silva e Silva José Diomedes Barbosa 《Tropical animal health and production》2014,46(2):385-389
To evaluate the prevalence and possible risk factors for brucellosis caused by Brucella abortus in water buffaloes in the state of Pará, Brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from Marajó Island and 1,108 from the mainland. The buffered acidified plate antigen (BAPA) screening test positively diagnosed 4.8 % (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-ME) confirmatory test affirmed 95.7 % (180/188) of the results. The brucellosis prevalence was 4.17 times greater in mainland animals than on Marajó Island, with the highest prevalence in Tailândia (11.30 %) and Paragominas (12.38 %). Brucellosis seroprevalence was significantly influenced (p?<?0.05) by reproductive status, with pregnant females being most vulnerable. These results demonstrate that brucellosis infection is active in the Brazilian region containing the largest buffalo population and that this disease poses a threat to public health and buffalo production in Pará. 相似文献
383.
Larissa Urzêdo Rodrigues Rubens Ribeiro da Silva 《Communications in Soil Science and Plant Analysis》2020,51(5):595-603
ABSTRACTThe expansion of agricultural activity in the Cerrado biome raises the importance of building soil fertility in micronutrients, however, the dynamics of these elements in different soil classes remains to be understood. The objective aimed to evaluate the availability of boron (B) in the soil in function of sources and incubation times to build the fertility of Oxisol and Entisol (Quartzipsamment). The experimental design was completely randomized with 50 treatments obtained in a 5 × 10 factorial scheme, being: five sources (boric acid, sodium octaborate, sodium tetraborate, boron oxide, and boron oxisulphate) and ten incubation times (0, 5, 10, 15, 25, 40, 55, 70, 85 and 100 days), with three repetitions. For all sources, the applied B dose was 4.0 mg dm?3 in soil samples of 0.5 dm3, with pH corrected to 6.0. In the two soils evaluated, borate fertilization promoted significant effects (p ≤ 0.05) on the availability of B and the efficiency of fertilization over the incubation time. The highest levels of B available in soils resulted from the use of less soluble sources, representing a fertilization efficiency above 75% when using boron oxisulphate in the Oxisol and greater than 85% with the use of boron oxide in the Entisol. The sources of greater solubility achieved an average efficiency of 10.66%. It is concluded that fertilization with borate sources affects the availability of boron to the building of soil fertility, however, the most soluble ones are less efficient to maintain good availability (>0.5 mg dm?3) after 40 days of application. 相似文献
384.
Hugo Teixeira Silva Paulo Sávio Lopes Júlio Carvalheira Delvan Alves Silva Alessandra Alves Silva Fabyano Fonseca Silva Renata Veroneze Gertrude Thompson Cláudio Napolis Costa 《Reproduction in domestic animals》2021,56(3):391-399
Reproductive efficiency is major determinant of the dairy herd profitability. Thus, reproductive traits have been widely used as selection objectives in the current dairy cattle breeding programs. We aimed to evaluate strategies to model days open (DO), calving interval (CI) and daughter pregnancy rate (DPR) in Brazilian Holstein cattle. These reproductive traits were analysed by the autoregressive (AR) model and compared with classical repeatability (REP) model using 127,280, 173,092 and 127,280 phenotypic records, respectively. The first three calving orders of cows from 1,469 Holstein herds were used here. The AR model reported lower values for Akaike Information Criteria and Mean Square Errors, as well as larger model probabilities, for all evaluated traits. Similarly, larger additive genetic and lower residual variances were estimated from AR model. Heritability and repeatability estimates were similar for both models. Heritabilities for DO, CI and DPR were 0.04, 0.07 and 0.04; and 0.05, 0.06 and 0.04 for AR and REP models, respectively. Individual EBV reliabilities estimated from AR for DO, CI and DPR were, in average, 0.29, 0.30 and 0.29 units higher than those obtained from REP model. Rank correlation between EBVs obtained from AR and REP models considering the top 10 bulls ranged from 0.72 to 0.76; and increased from 0.98 to 0.99 for the top 100 bulls. The percentage of coincidence between selected bulls from both methods increased over the number of bulls included in the top groups. Overall, the results of model-fitting criteria, genetic parameters estimates and EBV predictions were favourable to the AR model, indicating that it may be applied for genetic evaluation of longitudinal reproductive traits in Brazilian Holstein cattle. 相似文献
385.
Maria Isabel Gonzalez Urrego Raquel Silveira Pedreira Karine de Melo Santos Mariane Ceschin Ernandes João Paulo Fernandes Santos Thiago Henrique Annibale Vendramini Marcos Nogueira Eberlin Julio Cesar de Carvalho Balieiro Cristiana Ferreira Fonseca Pontieri Marcio Antonio Brunetto 《Journal of animal physiology and animal nutrition》2021,105(Z1):65-75
The strong odour of faeces and excessive production of gases in some dog breeds have long been a concern of owners. The pet food industry uses nutritional alternatives, such as high-quality ingredients and additives, to improve the odour of faeces. However, there are still some dog breeds, such as the French Bulldog, that present this problem due to the presence into the large intestine of indigested protein. Therefore, a deeper understanding of the volatile compounds that influence the odour of dog faeces is important. This study aimed to identify changes of faecal odour compounds that are most prevalent in French Bulldogs based on food containing different high-quality protein sources and their effect in sensory analysis. Four maintenance foods with different protein sources were formulated: P, poultry meal food; W, wheat gluten food; PW, poultry meal and wheat gluten food; and PWH, poultry meal, wheat gluten, and hydrolysed protein food. Eight adult French Bulldogs were arranged in a 4x4 Latin square design and adapted to foods for 28 days. Fresh faeces were collected for analysis of volatile organic compounds (VOCs) and sensory analysis. The means were compared by SAS, and statistical significance was indicated by p ≤ 0.05. No adverse effects were observed in the animals regarding VOCs, and a significant difference was observed in two of the 68 compounds identified. The animals fed a P food had higher concentrations of phenol in the faeces, whereas the indole compound was present at higher concentrations in animals fed the W food. P food was associated with higher odour perception during sensory evaluation. In summary, the source of protein in the foods had little impact on the composition of VOCs, and a greater perception of the odour was determined by sensory analysis when foods containing animal protein were administered. 相似文献
386.
Felícia Fonseca Tomás de Figueiredo Afonso Martins 《Forest Ecology and Management》2011,262(10):1905-1912
In Mediterranean environments, availability of water and nutrients are the main factors limiting the success of afforestation. As part of a wider project, an experiment was established in Northeast Portugal, aiming at testing the effect of several site preparation techniques on plant survival and growth (height and diameter) in a newly installed mixed forest stand. Results presented regard plant response during 42 months after plantation. The experimental protocol consisted in seven treatments described by mechanical operations that rank soil disturbance intensity from none to high, set in plots of 375 m2, randomly distributed in three blocks, in different topographic positions (gentle slope plateau, moderate slope shoulder, and steep mid-slope). Pseudotsuga menziesii (PM) and Castanea sativa (CS) forest species were planted in a 4 m × 2 m scheme and in alternate rows with 12 plants on each row per plot, summing up 72 plant per specie and treatment at start of the experiment. The results show that: (i) the highest mortality was observed immediately after the plantation and before the dry season, on the lowest intensity treatments; (ii) after the dry season, the highest mortality was also observed in treatments with the lowest intensity of soil disturbance, while the lowest values were found on the intermediate intensity treatments; (iii) during the experimental period, the effect of treatments on plant growth (height and diameter) was statistically significant; however, experimental results do not lead yet to a clear quantitative relationship between soil disturbance intensity due to site preparation and plant response under the conditions tested. 相似文献
387.
Granvogl M Koehler P Latzer L Schieberle P 《Journal of agricultural and food chemistry》2008,56(15):6087-6092
On the basis of a stable isotope dilution assay and derivatization with 2-mercaptobenzoic acid, the presence of the carcinogenic glycidamide ( 2) in processed foods was verified for the first time. Using (13)C-labeled 2 as the internal standard and the formation of the thioether derivatives, a new stable isotope dilution assay for the quantitation of 2 was developed. Application of the method on several potato samples revealed amounts between 0.3 and 1.5 mug/kg depending on the processing conditions. In a model experiment, the formation of 2 by an epoxidation of the double bond in acrylamide, that is, by a reaction with linoleic acid hydroperoxides, was established. This result was in good agreement with data showing that French fries processed in sunflower oil, which is high in linoleic acid, contained more 2 as compared to fries prepared in coconut oil. The derivatization procedure allows the simultaneous quantitation of acrylamide and glycidamide in foods. 相似文献
388.
Michelle Da Fonseca Santos Milene Möller Steven J. Clough 《Journal of Crop Improvement》2018,32(1):1-18
In Brazil, some of the most important insect pests causing damage to soybean (Glycine max) are stink bugs. Soybean production would increase if varieties with enhanced resistance were developed. The aim of this work was to examine different traits associated with plant development, and yield-related traits, in an F2:3 soybean population in a stink bug-infested field and to evaluate genetic parameters and correlations among those traits. The parents and progeny from 229 F2 plants developed by crossing a resistant cultivar (IAC-100) with a susceptible cultivar (CD-215) were evaluated in three replications in a single environment. Seven agronomic traits and eight indicators of insect resistance were measured. Genotypes showed significant differences for all traits except lodging. The grain-filling period exhibited a positive genotypic correlation of 0.66 with hundred-seed weight, whereas a negative genotypic correlation of ?0.53 was found between pod damage index (%) and weight of healthy seeds. In general, a shorter pod-filling period, lower weight of hundred-seeds, lower indices of pod damage, and higher seed-yield per plant were phenotypic traits of genotypes resistant to these insects. 相似文献
389.
Evaluation of the global DNA methylation in canine mast cell tumour samples by immunostaining of 5‐methyl cytosine
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C. Y. Morimoto M. V. Tedardi I. I. M. da Fonseca K. C. Kimura D. S. Sanches T. F. Epiphanio R. de Francisco Strefezzi M. L. Z. Dagli 《Veterinary and comparative oncology》2017,15(3):1014-1018
Cutaneous mast cell tumours (MCT) are the most common skin tumour in dogs, and to our knowledge, there are no previous studies regarding the global methylation of these tumours. DNA hypomethylation and hypermethylation have been described in several tumours and both mechanisms can lead to carcinogenesis. The purpose of this study was to evaluate the global DNA methylation in canine MCT. A total of 48 MCT samples were classified in grades 1, 2 and 3 or high‐grade or low‐grade. Monoclonal antibodies were used for the immunohistochemical detection of the 5‐methylcytosine. The immunostained nuclei were classified in strong, weak or negative pattern, and these were quantified in five distinct microscopic fields (40× objective) in each slide. The results showed that global DNA hypomethylation was predominant in grade 3, high‐grade, less differentiated MCT. These epigenetic changes in neoplastic mast cells warrant further detailed investigation aiming the establishment of tumour epigenetic therapies. 相似文献
390.
Rodrigo B. Nogueira Lucas A. Pereira Alice F. Basso Ingrid S. da Fonseca Lorena A. Alves 《Veterinary research communications》2017,41(1):33-40
The aim of this study was to prospectively evaluate the carotid-femoral pulse wave velocity (PWV) values in healthy dogs using pulse wave Doppler ultrasound. A secondary aim was to determine the feasibility of this method and to report the intra- and interobserver reproducibilities of the PWV in conscious dogs. The data were studied in 30 healthy, adult, male (n?=?15) and female (n?=?15) dogs. The time interval marked between the R wave peak of the electrocardiogram and the intersection of the blood flow wave upstroke of the Doppler spectrum with the baseline of zero frequency was determined for the carotid (T1) and for the femoral (T2) arteries. The distance covered by the pulse wave (L) was determined. The PWV was then calculated using the following formula: L/T2 - T1. The mean values of PWV calculated from the total sample (n?=?30) evaluated were 13.41?±?2.20 m/s. No significant statistical difference was observed for the PWV measurements between males (14.82?±?3.18 m/s) and females (12.64?±?2.45 m/s). The analysis revealed no intra nor interobserver differences. A reasonable reproducibility of the PWV measurements was showed by intraclass correlation coefficients (ICC), and the coefficients of variation (CV). These data demonstrate that noninvasive vascular Doppler analysis is a feasible and reproducible method to determine the carotid-femoral PWV in dogs. 相似文献