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131.
The objective of this study was to evaluate seminal plasma proteins from cattle and buffalo (Bubalus bubalis), to identify differences between related species. Sixteen buffaloes and 16 cattle between 30 and 60 months of age were used. Semen collection was performed by electroejaculation, followed by macroscopic and microscopic subjective analyses. After analysis, the samples were centrifuged at 800 g for 10 min, and the supernatant (seminal plasma) was recentrifuged at 10,000 g for 30 min at 4°C. The total protein concentration was determined by the Bradford method, and the proteins were digested in solution for mass spectrometry (nLC-MS/MS). Multivariate statistical analysis was used to evaluate the proteomics results by non-hierarchical clustering the considering exponentially modified protein abundance index (emPAI). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used for clustering. Proteomics identified 78 proteins, and multivariate analysis showed 4 that were over-expressed in buffaloes (cystatin C, prosaposin, peptide YY and keratin type II cytoskeletal 5) and 9 in cattle (spermadhesin-1, seminal plasma protein PDC-109, ribonuclease 4, metalloproteinase inhibitor 2, acrosin inhibitor 1, seminal ribonuclease, C-type natriuretic peptide, angiogenin-1 and osteopontin). Among the proteins identified in seminal plasma, the C-type natriuretic peptide and metalloproteinase inhibitors were described for the first time in buffaloes. Some protease inhibitors were found over-expressed in buffaloes, and important proteins in seminal plasma of cattle were not identified or were found at lower expression levels in buffaloes, which can contribute to reproductive performance in this species.  相似文献   
132.
Sheep milk is mainly intended to manufacture a wide variety of high-quality cheeses. The ovine cheese industry would benefit from an improvement, through genetic selection, of traits related to the milk coagulation properties (MCPs) and cheese yield-related traits, broadly denoted as “cheese-making traits.” Considering that routine measurements of these traits needed for genetic selection are expensive and time-consuming, this study aimed to evaluate the accuracy of a cheese-making phenotype imputation method based on the information from official milk control records combined with the pH of the milk. For this study, we analyzed records of milk production traits, milk composition traits, and measurements of cheese-making traits available from a total of 1,145 dairy ewes of the Spanish Assaf sheep breed. Cheese-making traits included five related to the MCPs and two cheese yield-related traits. The milk and cheese-making phenotypes were adjusted for significant effects based on a general linear model. The adjusted phenotypes were used to define a multiple-phenotype imputation procedure for the cheese-making traits based on multivariate normality and Markov chain Monte Carlo sampling. Five of the seven cheese-making traits considered in this study achieved a prediction accuracy of 0.60 computed as the correlation between the adjusted phenotypes and the imputed phenotypes. Particularly the logarithm of curd-firming time since rennet addition (logK20) (0.68), which has been previously suggested as a potential candidate trait to improve the cheese ability in this breed, and the logarithm of the ratio between the rennet clotting time and the curd firmness at 60 min (logRCT/A60) (0.65), which has been defined by other studies as an indicator trait of milk coagulation efficiency. This study represents a first step toward the possible use of the phenotype imputation of cheese-making traits to develop a practical methodology for the dairy sheep industry to impute cheese-making traits only based on the analysis of a milk sample without the need of pedigree information. This information could be also used in future planning of specific breeding programs considering the importance of the cheese-making efficiency in dairy sheep and highlights the potential of phenotype imputation to leverage sample size on expensive, hard-to-measure phenotypes.  相似文献   
133.
Tropical Animal Health and Production - The objective of this study was to analyze the correlation between condemnations in slaughterhouses situated in Minas Gerais State and notifications to the...  相似文献   
134.
Plant shoot production is closely related to root development. To obtain greater grass persistence, nutrient uptake by roots and recovery after defoliation, it is necessary for the plants to have well developed root systems. The study aimed to evaluate the morphological, productive and nutritional characteristics of Panicum maximum cv. Tanzania roots in response to combinations of nitrogen (N), potassium (K), and boron (B) rates in nutrient solution. Root dry mass, total root length, and total root surface increased with the combination of N and K rates. Boron rates did not affect any of the studied parameters. Greater concentrations of ammonium than nitrate were found in the root tissues. Root specific length and root specific surface decreased as rates of N and K increased. The N and K supply caused an increase in the morphological and productive aspects of the root system, thus enhancing the capacity for nutrient absorption.  相似文献   
135.
Understanding of tillage effects on soil chemical properties and cations in soil solution dynamics is essential for making appropriate land-management decisions. Measurements were made after more than 25 years of different tillage treatments: conventional tillage (CT) and conservation tillage, which includes no-till (NT) and minimum tillage (MT). pH and bulk density did not show important changes but exchangeable cations and cations in soil solution were affected by depth and different tillage. The highest concentration of exchangeable Ca2+ and Mg2+ was found in NT, decreased in MT and the lowest concentration was found in CT (mean values were 26.0, 24.4 and 23.3 cmolc kg?1 for exchangeable Ca2+ and 4.2, 3.7 and 3.3 cmolc kg?1 for exchangeable Mg2+ in NT, MT and CT, respectively). In addition, the highest concentration of exchangeable Na+ was found in NT, decreased in CT and the lowest concentration was found in MT. However, the highest concentration of exchangeable K+ was found in MT. A significant depth effect was observed for cations in soil solution: Na+ increased with depth whereas K+ and Ca2+ decreased with depth. This study aims to demonstrate the effect of tillage on the distribution and concentration of certain chemical soil properties.  相似文献   
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137.
Foliar spots caused by Pseudomonas coronafaciens pv. garcae (Pcg), Pseudomonas amygdali pv. tabaci (Pat) and Pseudomonas cichorii (Pch) are major bacterial diseases that can reduce coffee production. However, little is known about the genetic diversity and molecular mechanisms underlying the pathogenicity to coffee plants of these bacteria. In this study, genome sequences of Pcg, Pat and Pch strains isolated from coffee plants in Minas Gerais state, Brazil, were used to assess their variability and plasticity, and compare their type III secretion system (T3SS) and apoplastic effector repertoires as well as tabtoxin biosynthetic/detoxification genes. Genomic diversity was found for all three phytopathogens, among which Pch possesses the highest number of exclusive proteins. The Pcg genome is the most stable whereas that of Pch is the most plastic, which is related to their host ranges. When compared with those of Pseudomonas syringae pv. tomato DC3000, hrp/hrc gene sequences are more conserved in Pcg and Pat than in Pch, which also possesses the smallest T3SS and the largest apoplastic effector repertoires. The only T3SS effector family common to all three pathogens is AvrE, suggesting that, as for other plant–Pseudomonas interactions, it may play a crucial role for pathogenicity towards coffee plants. Apoplastic proteins associated with maintaining the redox balance and degrading proteins/peptides not previously described as important in plant–bacteria interactions were found. Gain/loss of the tabtoxin biosynthetic cluster with retention of the antitoxin gene was observed, indicating that tabtoxin production is not a limiting factor for the occurrence of mixed infections.  相似文献   
138.
The increase in tropic grass production and its estimation by the SPAD value can be related to combined supply of nitrogen and magnesium. The objectives were to check the effect of magnesium (Mg) rates on the productive response of Marandu palisadegrass to nitrogen (N) rates; correlate the supply of N and Mg with the SPAD reading; establish the use of SPAD reading as a way of predicting the N and Mg concentrations in diagnostic leaves (DL) and shoot dry matter (SDM). The experiment was carried out in a greenhouse. Five N rates and five Mg rates were used in nutrient solutions, in a fractionated 5 × 5 factorial design with four replications. High N and Mg rates resulted in high dry mass yield and leaf area, in greater numbers of leaves and tillers. The correlations between SPAD reading and SDM, N and Mg in DL were high, high and low, respectively.  相似文献   
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140.
In this work a new control strategy for grain aeration systems was proposed. This strategy was implemented in a software package called AERO and relates four conditions which depend on real time data acquisition and on the process simulation. The main advantage of AERO controller is that it can be used in different geographic regions, during different seasons and with different aeration systems, automatically adjusting its set points. The objectives of AERO controller are to equalize the temperatures inside the bin, to cool the grain mass whenever is possible and to maintain the moisture content under safe conditions. The results showed that the proposed strategy is efficient to achieve these objectives. Moreover, significant energy saving has been achieved with the AERO controller.  相似文献   
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