Suchergebnisse

This study aimed to evaluate the chemical composition and fatty acid (FA) profile of chopped forage and silage of BRS Capiaçu elephant grass at four regrowth ages: 50, 70, 90 and 110 days. A randomized block design with five replications was used. The ensiling was carried out manually in experimental silos without wilting using no additives or bacterial inoculants. The results were analyzed using mixed models (P < 0.05). The model included treatment (regrowth age) as a fixed effect and block as a random effect. Linear and quadratic effects of the treatments were analyzed using orthogonal contrasts. There were linear increases in the dry matter (DM, g kg-1) and lignin (g kg-1 DM) contents and linear reductions in the in vitro DM digestibility (g kg-1) of chopped grass and silage as a function of regrowth age (P < 0.001). Quadratic effects (P ≤ 0.01) were observed for the chopped grass contents (g kg-1 DM) of crude protein (CP), ether extract (EE) and neutral detergent fiber (NDF) as a function of regrowth age. There were linear decreases (P < 0.0001) in the CP content (g kg-1 DM) and pH and linear increases (P < 0.001) in the EE and NDF contents (g kg-1 DM) in the silage as a function of regrowth age. There were linear decreases (P < 0.01) in the chopped grass contents and linear increases (P < 0.05) in the silage contents of total FAs, linoleic and α-linolenic acids (g kg-1 DM) asa function of regrowth age. BRS Capiaçu elephant grass must be harvested at up to 70 days of regrowth to obtain forage with good nutritional value and the highest levels of linoleic and α-linolenic acids (g kg-1 DM). To produce silages with adequate pH values and the highest levels of linoleic and α-linolenic acids (g kg-1 DM), BRS Capiaçu must be harvested between 90 and 110 days of regrowth.

Staphylococcus is one of the most frequent etiological agents of bovine mastitis, causing economic losses to milk farming. This study aimed to describe the milk production and management practices in 15 herds located in three microregions of the State of Rondônia and to identify the antimicrobial resistance profile of 97 isolates of the genus Staphylococcus from these herds. The isolates were subjected to antimicrobial susceptibility tests using the agar diffusion method. Twenty-nine S. aureus isolates were selected to determine their minimum inhibitory concentration (MIC). In the farms studied, the breeding system was semi-intensive, with the Girolando breed being predominant. Milking was performed predominantly using a mechanical milking system (86.7%), twice a day (66.7%), in the presence of the calf (53.8%). The average number of lactating cows in the farms was 24, with an average milk production of 204.9 L d-1 and a milk productivity of 10.2 L animal-1 d-1. The use of antimicrobials for the treatment and prevention of bovine mastitis was reported for all properties, and therapy for dry cows was adopted in 80% of the herds. The percent susceptibility to antimicrobials ranged from 85.5% to 100% for S. aureus, 22.2% to 88.9% for coagulase-positive staphylococci (CPS), and 69.2% to 100% for coagulase-negative staphylococci (CNS), with the highest resistance frequencies for penicillin, ampicillin, and tetracycline. Among the S. aureus isolates, 100% susceptibility to oxacillin, cefalexin, and gentamicin was observed, and among the CNS isolates, 100% susceptibility to gentamicin was observed. None of the antimicrobials tested showed 100% in vitro effectiveness for CPS. CPS and CNS presented lower percentages of susceptibility to penicillin, ampicillin, and tetracycline than the S. aureus isolates. Twelve resistance patterns were detected, six of which were multiresistance patterns. The most prevalent resistance patterns were penicillin and ampicillin (PEN-AMP) and penicillin, ampicillin, and tetracycline (PEN-AMP-TET). Results of the MIC assay revealed that all 29 S. aureus isolates were susceptible to cephalothin, cefoxitin, tetracycline, and erythromycin, whereas 25 (86.2%) were susceptible to penicillin.

Iron and zinc deficiencies in humans can cause serious health problems. Increasing the iron (IC) and zinc (ZC) concentrations in common bean (Phaseolus vulgaris L.) grains using genetic breeding can be an effective strategy to prevent these problems. Thus, the aims of this study were i) to investigate the importance of genetic, environmental, and genotype-by-environment interaction effects on IC and ZC in common bean grains; ii) to select cultivars that have high mean values and phenotypic stability for IC and ZC, as well as high protein concentration (PC), high yield, and standard commercial grain quality; and iii) to investigate whether there is a genetic relationship between these traits. A total of 34 cultivars were evaluated in 19 different environments. Genetic variability was observed among the genotypes for all traits. For IC and ZC, the environmental effect represented most of the total variation (63% and 65%, respectively), and the effect of the G × E interaction was 18% for IC and 15% for ZC. The genetic correlations between IC, ZC, and PC were positive, indicating that the selection of one of these traits resulted in gains for the other. The genetic correlations between IC or ZC with yield or 100-grain weight were low or intermediate, but negative, indicating that it is important to evaluate these traits at all stages of breeding programs that focus on developing cultivars with high IC and ZC. The cultivar BRS Sublime, with the carioca grain type, combined high IC, ZC, and PC, high yield, and grains of commercial size.

The common bean production system is majorly based on the use of granular fertilizers to provide nutrients for the crop. Studies on the use of liquid fertilization at an appropriated depth and, seed inoculation with Rhizobium tropici can provide significant increases in the grain yield of the common bean. The objective of this study was to determine the growth and productivity of common bean as affected by N-P formulations, application depths and the inoculation with R. tropici. Field experiments were carried out in 2015 and 2016 cropping years using a complete block design, in a 2x2x2 factorial arrangement, with four replicates. The treatments involved the combination of N-P formulation (granular and liquid), two application depths of the N-P formulation (6 and 12 cm) and with or without rhizobia inoculant. The plant density (PD), number of pods (NP), number of grains (NG), mass of 100 grains (M100) and grain yield (GY) were determined. The granular and liquid N-P formulations provided similar results for PD, NP, NG, and GY of common bean. Similarly, the application depth of the N-P formulations did not affect GY. Inoculation of the seed with R. tropici stimulated NP and NG, increasing GY. Growth and productivity parameters were equally affected by the type of formulation and application depth; however, GY was greater with rhizobial inoculant. Thus, the liquid N-P formulation, applied at 6 cm depth, associated with rhizobial inoculant can improve the crop management providing better control of application uniformity, minimal soil mobilization, less fuel consumption, and increased grain yield.

The growth and yield of sunflower plants can be influenced by the plant population arrangement and the type of irrigation system adopted to meet the water requirements of the crop. This study examines the influence of different irrigation systems and spacings between planting rows on the development of sunflower cultivars for the sub-middle region of São Francisco Valley. The experiment was laid out in a randomized block design with a split-plot arrangement in which the plots consisted of three irrigation systems (drip, micro-sprinkler and sprinkler); sub-plots were represented by three spacings between planting rows (0.65, 0.55 and 0.45 m); and sub-sub-plots corresponded to two sunflower cultivars (Hélio 251 and Hélio 360). The following variables were analyzed: plant height; number of leaves; stem diameter; number of heads; head diameter; dry biomass of stems, leaves and heads; and achene yield. The different irrigation systems and row spacings markedly influenced the growth of the sunflower cultivars. The highest yield of cultivar Hélio 251 was obtained with the drip irrigation system and 0.55 m spacing. Cultivar Hélio 360 achieved the highest yields when irrigated by the micro-sprinkler system at 0.55 and 0.45 m spacing. In the sprinkler irrigation system, cultivar Hélio 360 obtained the highest yield at 0.45 m spacing.

This study aimed to evaluate the chemical composition and fatty acid (FA) profile of forage and silage of a seed-propagated elephant grass genotype called "PCEA" harvested at 75, 90, 105 and 120 days of regrowth. A randomized block design with five replications was used. The results were analyzed by mixed models (P < 0.05) that included treatment (regrowth age) as a fixed effect and block as a random effect. Linear and quadratic effects of the treatments were analyzed using orthogonal contrasts. There was linear increase on total dry matter (DM) forage production and linear decrease on leaf:stem ratio as a function of the increase in regrowth age (P < 0.05). In response to the advance of regrowth age, "PCEA" forage and silage showed linear decreases on crude protein (CP) content (g kg-1 DM) and in vitro DM digestibility (g kg-1); and linear increases on DM (g kg-1), lignin (g kg-1 DM), and acid detergent insoluble protein (%CP) contents (P < 0.05). All "PCEA" silages had DM content < 200 g kg-1, pH > 4.0, and ammonia N content > 10% total N. In response to the advance of regrowth age, linear decreases (P < 0.05) were observed on forage and silage linoleic, α-linolenic, and total FA contents (g kg-1 DM). From 75 to 120 days of regrowth, the seed-propagated elephant grass genotype "PCEA" presents forage and silage with low nutritional quality for feeding dairy cattle, moderate to high linoleic acid contents, and moderate to low α-linolenic acid contents. The "PCEA" forage and silage obtained from 75 to 120 days of regrowth presents low potential for production of milk naturally enriched with bioactive FAs beneficial to human health.

This study was carried out in a randomized block design in a 2 x 2 factorial arrangement with the aim of evaluating the short-term changes in the plasma and milk fatty acid (FA) profiles of Holstein x Gyr cows (444±84 kg; 75±31 days in milk; 15.4±4.8 kg day-1 of milk) fed 600 g kg-1 DM chopped elephant grass-based diets supplemented with 45 g kg-1 DM sunflower oil (SO) for 21 days. Two types of SO were evaluated: high oleic/low linoleic acid (HO) and medium oleic/medium linoleic acid (MO). The concentrates containing SO were supplied separately from forage twice a day (TAD) or as part of a total mixed ration (TMR). Temporal changes were analyzed by mixed models (P < 0.05) using six, four and seven repeated measures over time for FA intake and the plasma and milk FA compositions, respectively. There was higher oleic acid intake in HO SO-fed cows, while higher linoleic and α-linolenic acid intake were observed in MO SO-fed cows. TADfed cows had a higher plasma vaccenic acid content than TMR-fed cows, while MO SO-fed cows had higher plasma vaccenic and rumenic acid contents than HO SO-fed cows. As a function of day, there were linear increases in oleic and linoleic acid intake; plasma contents of oleic, vaccenic and linoleic acids; and the milk fat content of linoleic acid, while quadratic effects were adjusted for the milk fat contents of palmitic, oleic, vaccenic and rumenic acids. In comparison with TMR-fed cows, the milk fat of TAD-fed cows produced between days 13 and 17 showed an FA profile that was more nutritionally desirable for human health, with lower contents of hypercholesterolemic FAs and higher contents of oleic, rumenic and vaccenic acids. Between days 15 and 16, the vaccenic and rumenic acid contents in the milk fat of MO SO-fed cows were 81% higher than those obtained from HO SO-fed cows, which on the 14th day had a 14% higher oleic acid content in milk fat. Lower milk fat levels of hypercholesterolemic FAs were produced between days 13 and 14 by cows fed both types of SO.

Assessment of energy efficiency (EE) enables the evaluation of the sustainability of agrosystems, as well as decision-making regarding reduction in production costs and environmental pollution and even to increase production in a sustainable way. In this context, the objective of this study was to assess energy efficiency in maize in different regions of Brazil. For this purpose, 32 areas of maize crop distributed across the major producing states and regions were assessed. Energy inputs and outputs of agricultural operations and/or agricultural inputs were calculated by multiplying the amount used by their calorific value or energy coefficient at each stage of production. Energy efficiency was calculated as the ratio between the total output energy and the total input energy during the production process. For every megajoule (MJ) of energy consumed in the production of second-crop maize and first-crop maize seasons, 9.9 and 8.7 MJ respectively of renewable energy were produced in the form of grain. In both maize cropping seasons, most of the energy use was attributed to fertilizers, herbicides and fuel. To be representative the evaluation of energy efficiency of the maize crop should be performed in different Brazilian cultivation regions, as it will represent different edaphoclimatic and management conditions spread over the national territory within an agricultural year.

The objective of this study was to develop a cake rich in resistant starch, with green banana flour (GBF), of good sensory acceptance. In step 1, four cake formulations were prepared with increasing concentrations of GBF and evaluated for acceptability and purchase intention. In step 2, four new formulations were made by modifying the most accepted formulation in step 1, in addition to the formulation without GBF (control). The resistant starch content, proximate composition, total calorific value, and sensory acceptance data were obtained. The formulation with cocoa powder and dried banana (E1F4) achieved 97.78% overall acceptance and higher purchase intent. In step 2, the formulations with 14% and 18% GBF were the most accepted for flavor, texture/softness, and overall acceptance. Adding the categories of "would certainly buy" and "would probably buy", 53.33% of consumers would buy the cake with 14% GBF and 48.89% would buy the cake containing 18% GBF. The incorporation of GBF increased the resistant starch contents of the formulations as compared with the control. Ash content was highest in the formulation with 26% GBF (2.22%) and lipid content in the control formulation (11.58%). The treatments did not differ in terms of moisture content. Protein content decreased as the GBF content in the formulations was increased. The total dietary fiber content of the formulations was 9.30%. Carbohydrate content and calorific value also did not vary. The mean values of L*, a*, b*, C*, and h* showed that the cakes had an intense dark brown color. In conclusion, the addition of 14% and 18% GBF to the cake resulted in a product of high sensory acceptance, with high purchase intent, a resistant starch content 7.21 and 8.34 times higher than those in the control cake.

Multifunctional microorganisms (MMs) can have beneficial effects on plants through direct and indirect mechanisms. This study aimed to determine the effect of MMs on shoot and root biomass production; gas exchange; content of macronutrients in the shoots, roots and grains; yield components; and grain yield of common bean plants. A completely randomized design with twenty-six treatments and three replications was used under controlled conditions. Treatments consisted of the application of MMs and their combinations in pairs, with the nine rhizobacteria isolates BRM 32109, BRM 32110 and 1301 (Bacillus sp.), BRM 32111 and BRM 32112 (Pseudomonas sp.), BRM 32113 (Burkholderia sp.), BRM 32114 (Serratia sp.), 1381 (Azospirillum sp.) and Ab-V5 (Azospirillum brasilense); an edaphic fungal isolate T-26 (Trichoderma koningiopsis); and a control (without MMs). These MMs were applied at three time points: microbiolization of the seeds, watering the soil seven days after sowing (DAS) and spraying the plants with 21 DAS. In comparison to the control plants, the isolates 1301 and T-26, in addition to the combinations Ab-V5 + T-26, BRM 32114 + BRM 32110 and 1381 + T-26, provided better results, with an increase of 36.5% in the grain yield, a higher accumulation of biomass (78.0%) and a higher content of N, P and K (42.6, 67.8 and 25.7%, respectively) in the shoots of common bean plants. Therefore, the results allow us to infer that the use of MMs is a good strategy for increasing common bean grain yields.

Sweet cassava must be rapidly cooked and meet the sensory and technological requirements of consumers. The objectives of this study were to evaluate the culinary quality of sweet cassava varieties harvested at three ages and obtain the sensory profile of these varieties using the check-all-that-apply method (CATA). Roots of three cassava varieties released or recommended by Embrapa (BRS Aipim Brasil, BRS Dourada and Saracura) and the commercial variety Eucalipto, harvested at nine, 12 and 15 months of age, were evaluated for physical, chemical and sensory aspects. At nine months of age, the Saracura, BRS Aipim Brasil and BRS Dourada varieties did not differ in cooking time, averaging 41.62 min. The Eucalipto variety had similar cooking times at the three harvest ages, averaging 21.83 min. There was a difference between the four varieties at nine months, with Saracura exhibiting the lowest acceptance score (5.0) and differing from the Eucalipto variety, which showed an average score of 6.3. At 12 months of age, there was a significant increase in the acceptance of the Saracura and BRS Aipim Brasil varieties, which did not differ from Eucalipto and had an average score of 6.4. Consumers perceived differences between the sensory characteristics of the cassava varieties using CATA. The sensory terms "creamy", "soft" and "sticky" can be associated with greater acceptance of cooked cassava roots, whereas terms such as "floury", "slightly bitter", "no taste", "hard" and "fibrous" can be associated with less acceptance and are therefore undesirable from the consumer's point of view. Principal component analysis showed that the age at which the roots were harvested had a great effect on the culinary quality of cassava, regardless of the evaluated variety. The commercial variety Eucalipto was well-accepted by the consumers irrespective of root age and can be harvested at any of the evaluated ages. For the Saracura, BRS Aipim Brasil and BRS Dourada varieties, harvesting is recommended at 12 or 15 months so that better quality roots are obtained.

Caprine arthritis encephalitis is a lentiviral disease that leads to considerable losses in goat farming. In the acute phase of viral infection, though antiviral antibodies are produced by the host's immune system, they are not sufficient to be detected by serological tests. Acute infections begin with an incubation period, during which the viral genome replicates and host innate responses are initiated. Matrix metalloproteinases (MMPs) are enzymes that play an important role in the physiological and pathological processes of tissue remodeling. The present study aimed to evaluate the expression of MMPs and their activity in the blood serum of goats experimentally infected with caprine arthritis encephalitis virus (CAEV). Five dairy goats, aged 3-4 years, were intravenously inoculated with CAEV Cork strain (titer: 105-6 TCID50/mL) after being tested negative for CAEV thrice at consecutive intervals of 30 days using western blot analysis and nested-PCR. The study included three stages: S1 or pre-infection stage; S2 or seroconversion stage, corresponding to the occurrence of first seroconversion; and S3 or post-seroconversion stage, corresponding to 23 weeks after seroconversion. Zymography was performed for the samples using gelatin zymography gels (12.5%), which were subjected to electrophoresis at 170V, 1A, and 300W for 50-70 min. The density of MMP-2 was found to be lower at S1 (1456.20 pixels) than that at S2 and S3 (1943.80 and 2104.40 pixels, respectively) (P < 0.05); and the density of MMP-9 was found to be lower at S3 (133.60 pixels) than that at S1 and S2 (359.60 and 370.60 pixels, respectively). The density of proMMP-2 was low at S1 and S3 (130.45 and 145.20 pixels, respectively). On the other hand, the density of proMMP-9 was statistically different between S1 and S3 (89.22 vs. 415.60 pixels). Both proMMP-2 and proMMP-9 were absent at S2. Thus, MMP-2 and MMP-9 exhibited opposite behaviors depending on the stage of infection. As the greatest activity of MMP-2 was detected at stage S3, we suggest that MMP-2 can be used as a biomarker for complementary diagnosis of acute CAEV infection. In addition, the presence of proMMP-13 can be used to indicate active viral infection.