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Sugarcane management systems affect soil attributes such as the carbon cycle. This fact has stimulated the sugar and alcohol industry to refine the sugarcane production systems by replacing the pre-harvest burning (PB) and manual harvest with mechanized harvesting followed by residue deposition. The aim of this study was to evaluate different management systems with respect to C cycling carbon dioxide and soil parameters (chemical, physical and biological) which were determined over the season. Three sugarcane cultivation systems were evaluated at the following periods: (a) PB, (b) 5-year green harvest and (c) 10-year green harvest. The results indicated that CO2 emission was 36% greater in the 10-year sugarcane green harvest system than in the PB system. The bulk density and macroporosity were the factors that were most affected by the different sugarcane management systems and that significantly influenced soil CO2 emissions. The principal component analysis showed that soil CO2 emission was 18% influenced by base saturation (V%) and 14% by pH, especially in the PB area. Additionally, 19% was affected by carbon and macroporosity in the 5- and 10-year green harvest areas, respectively. From our results, it can be concluded that the most CO2 emissions are in the areas of sugarcane green, this is due to the higher carbon concentration when compared with the area of burning sugarcane. The parameters that most influenced the CO2 emissions were bulk density, porosity, macroporosity, pH and V%.  相似文献   
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The aim of this study was to identify possible effects of different vaccination strategies (concomitantly or not) against brucellosis and clostridia on intake, performance, feeding behavior, blood parameters, and immune responses of dairy heifers calves. Fifty heifers calves were enrolled [38 Gyr (Zebu, Bos taurus indicus) and 12 5/8 Holstein Gyr]. At 120 d of age, animals were randomly distributed among 3 groups: B (n = 18), vaccinated against brucellosis; C (n = 14), vaccinated against clostridia and CB (n = 18), vaccinated concomitantly for both. Rectal and thermographic temperatures were evaluated on days 1, 0, 1, 2, 3, 5, 7,10, 14, and 28 relatives to the vaccination day. Feed and water intake, body weight (BW), and feeding behavior were monitored daily by an electronic feeding system. Blood was sampled on days 0, 3, 7, 14, and 28, relative to the vaccination day for determination of glucose and -hydroxybutyrate (BHBA) concentrations. Blood sampled on day 0 (prevaccination) and on days 28 and 42 were used to evaluate the immune response against Brucella abortus and clostridia. There was an increase in rectal temperature between the first and the third day postvaccination in the 3 groups. The thermography revealed an increase of local temperature for 7 d on groups B and CB. Group C had increased local temperature for a longer period, lasting for up to 14 d. Dry mater intake was reduced for groups B and CB, but no alteration was observed for group C. No alterations regarding initial BW, final BW, average daily weight gain, and feed efficiency were observed. No differences were observed for the 3 vaccination groups for blood parameters throughout the evaluation period. The concomitant vaccination against brucellosis and clostridia led to lower neutralizing antibody titers against epsilon toxin of Clostridium perfringens and botulinum toxin type C of C. botulinum (C > CB > B). When cellular proliferation assay and serological tests to B. abortus were evaluated, no differences were observed between groups B and CB. The present results indicate that the concomitant vaccination against brucellosis and clostridia has no relevant impact on the intake, performance, and feeding behavior of dairy calves. However, the concomitant vaccination of vaccines against these 2 pathogens impacts animal immunity against clostridial infections.  相似文献   
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BACKGROUND: Patent ductus arteriosus (PDA) size and morphology influence the selection of the kind and the size of the embolization device used to effect shunt closure. HYPOTHESIS: That echocardiographic measurement of PDA in dogs is accurate. ANIMALS: Forty-five client-owned dogs with PDA. METHODS: Prospective observational study. Echocardiographic and angiographic data were compared. RESULTS: Measurement of the ductus in color Doppler echocardiography (CD-E) and 2-dimensional echocardiography (2D-E) was achieved from left parasternal views in 43 of 45 unsedated dogs (96%). In these 43 dogs, the angiographic minimal PDA diameter was 3.72 +/- 1.59 mm, and the diameter of the PDA ampulla was 8.46 +/- 3.01 mm. The CD-E minimal PDA diameter ranged from 2.3 to 9.5 mm (median, 4.0 mm). There was a significant mean difference to the angiographic measurements (1.15 +/- 0.95 mm; P < .0001). An agreement in a 1-mm range was found in 21 of 43 dogs (48%). The 2D-E minimal PDA diameter was 3.73 +/- 1.78 mm, and the mean difference to the angiographic measurements was not significant (0.00 +/- 0.72 mm; P = .98). An agreement in a 1-mm range was found in 31 of 43 dogs (72%). The 2D-E measurement of the PDA ampulla revealed a significant mean difference to the angiographic data (1.95 +/- 2.43 mm, P < .0001). An agreement in a 2-mm range was found in 21 of 43 dogs (49%). CONCLUSIONS AND CLINICAL IMPORTANCE: The 2D-E from the left cranial parasternal view is an excellent noninvasive method to estimate the PDA minimal diameter before doing catheter intervention.  相似文献   
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The aim of this study was to define the differences between the Brazilian states that export and do not export meat to the European Union (EU) and to identify the variables that are important to meet the export requirements. Infrastructure and computerization of the control of animal transit in Brazil that impact on regional health status were evaluated and linked to other variables such as status for foot and mouth disease (FMD) and qualification to export meat to EU. Variables related to transit control of bovines implemented by the state agencies of animal health and inspection in each Brazilian state were evaluated. Using a discriminant analysis, four variables were selected that explained the variation between Brazilian states that were “free” and “not free” of FMD while another four were selected to explain the variation between the zones “approved” and “not approved” to export meat to the EU, including number of official veterinarians, total transit of bovines and buffaloes, total number of animal transit certificates issued for bovine and buffaloes at the state or zone level, and total number of municipalities in the state or zone. It was possible to correctly discriminate between “free” and “not free” FMD states or zones. Variables related to animal transit are important in assessing the state for the classification of animal health situation and for EU approval for the exportation of meat.  相似文献   
8.
Left ventricular (LV) diastolic function was evaluated in 16 cats with primary hypertrophic cardiomyopathy (HCM) using pulsed Doppler (PD) assessment of transmitral flow and isovolumic relaxation time. Data obtained was compared to data from 12 healthy, adult, research cats. Compared to normal cats, the HCM group showed significantly (p value less than 0.05) reduced early LV inflow velocities (mean +/- standard error [SE], peak velocity of 0.70+/-0.04 m/s versus 0.54+/-0.04 m/s and integrated velocity of 0.48+/-0.08 m/s versus 0.37+/-0.03 m/s); a reduced rate of deceleration of early inflow (mean+/-SE, -12.0+/-1.0 m/s2 versus -5.1+/-1.1 m/s2); prolonged isovolumic relaxation time (mean +/- SE, 45.7+/-3.3 ms versus 76.0+/-3.1 ms); and increased atrial systolic flow velocities (mean +/- SE, peak velocity of 0.29+/-0.04 m/s versus 0.48+/-0.04 m/s and integrated velocity of 0.21+/-0.03 m/s versus 0.34+/-0.03 m/s). The results suggest that PD provides a noninvasive method of identifying and quantifying functional diastolic impairment in cats with HCM.  相似文献   
9.
Paraoxonase‐1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry‐over effects of PON1 on pre‐implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml?1 of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml?1, respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose‐dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose‐related positive effects on embryo development rates to blastocysts.  相似文献   
10.
Possible Root Infection of Cercospora beticola in Sugar Beet   总被引:1,自引:0,他引:1  
A potential primary infection site of the foliar pathogen Cercospora beticola in sugar beet is described. Sugar beet seedlings of the susceptible cv. Auris were grown in a standard soil for 14 days. A monoconidial culture of a C. beticola isolate was grown to produce conidia. In experiment 1, roots were immersed in a conidial suspension of isolate code IRS 00-4, or in tap water (control), for 2 days. After incubation seedlings were potted in a peat – fine river sand mixture and placed at low relative humidity (RH) (<80%) or high RH (100%). Twelve days after infection, seedlings at high RH showed more disease incidence (90%) than seedlings grown at low RH (disease incidence = 25%), whereas no disease symptoms developed in the control seedlings. Cercospora leaf spots (CLSs) developed on the cotyledons, leaves, petioles and stems of the seedlings. In experiment 2, roots were immersed in a conidial suspension of isolate code IRS 00-2 for 5 h. Thirty-four days after infection at high RH, 100% disease incidence was observed in the treated seedlings and one CLS in the control treatment. First indications of leaf spot development were observed as reddish purple discolouration of individual parenchymatic cells. Because splash dispersal and symptoms due to infested soil were excluded, we showed that it is possible to obtain CLS symptoms in sugar beet seedlings when their roots were immersed in conidial suspensions of C. beticola, thus demonstrating that roots can be a primary infection site.  相似文献   
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