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31.
Portugal has a diverse common bean germplasm, which is still grown in farmers' fields. In this work, we searched for resistance to rust (Uromyces appendiculatus) and powdery mildew (Erysiphe diffusa) in a representative collection of the Portuguese common bean germplasm. Despite many accessions depicting intermediate levels of resistance when compared to the susceptible check, 24 and 13 accessions showed low levels of infection, in spite of a compatible interaction (disease severity (DS) values lower than 5% and infection type (IT) of 4), to rust and powdery mildew, respectively, indicative of partial resistance. Moreover, a resistant reaction was observed in 11 accessions when inoculated with powdery mildew (IT = 0–1) and in additional 11 accessions (one in common) when inoculated with rust (IT = 0–2). The levels of resistance found in this report anticipate great potential of the Portuguese national germplasm, recently reported as genetically closer to the Andean common bean gene pool, for disease resistance breeding of this important crop.  相似文献   
32.
The main objective of this study was to evaluate the effect of peripartal administration of a commercially available nonspecific immune stimulant (mycobacterium cell wall fraction; MCWF [Amplimune, NovaVive Inc., Napanee, ON, Canada]) on the incidence of disease during early lactation and subsequent fertility of dairy cows. A second objective was to characterize the dynamics of circulating white blood cells (WBC) and metabolic markers following treatment administration. Cows in an United States Department of Agriculture (USDA) organic-certified dairy herd were blocked by parity and, based on sequential calving dates, randomly assigned to receive two injections (5 mL s.c.) of either a placebo (saline solution) as a control (CON; n = 71) or MCWF (n = 65) at enrollment (7 d before expected calving) and within 24 h after calving. Blood samples were collected from a subsample of the study population (MCWF = 16; CON = 18) for WBC count at enrollment, at day 2 post enrollment, and at days 1, 3, 7, and 14 after calving. Serum fatty acids, beta-hydroxybutyrate, and Ca concentrations were determined at days 1 and 7 postpartum (MCWF = 21; CON = 21). Main outcome variables included incidence risk of peripartal and early lactation health disorders and pregnancy at first artificial insemination (AI), at 100, and at 150 days in milk (DIM). In addition, the average daily milk yield up to 90 DIM and death and live culling before 305 DIM were compared. Treatment effects were assessed using multivariable logistic regression, time-to-event analyses, and repeated measures analysis of variance (ANOVA). A treatment effect on the incidence risk of some of the health disorders in the study was established. Incidence risk of metritis and clinical mastitis <28 DIM was smaller in MCWF than in CON cows (36.9% vs. 50.7% and 6.3% vs. 19.7%, respectively). On the contrary, the incidence risk of respiratory disease <28 DIM was smaller in CON (0%) than in MCWF (7.7%). Reproductive performance of multiparous cows was affected by MCWF administration: pregnancy at first AI and pregnancy at 100 and 150 DIM were greater in MCWF than in CON (35.6% vs. 19.2%; 51.1% vs. 25.0%; and 64.4% vs. 40.4%, respectively). Overall, median intervals from calving to pregnancy were 90 vs. 121 d in MCWF and CON cows, respectively. No treatment effects on the dynamics of circulating WBC or in postpartum metabolic status were established. No differences for milk yield or for the proportion of cows that survived up to 305 DIM were determined, although cows in MCWF left the herd earlier than cows in CON. In conclusion, incidence risks of metritis and mastitis in early lactation were smaller in cows receiving MCWF, whereas the incidence risk of respiratory disease was smaller in CON. Fertility significantly improved in MCWF compared with CON cows. As this study was performed in an organic-certified dairy, specific health and reproductive management practices may affect the external validity of the current findings.  相似文献   
33.
Bacterial communities in sediments underneath milkfish cages and adjacent off‐cage areas in Bolinao, Lingayen Gulf, West Philippine Sea were characterized using PCR‐denaturing gradient gel electrophoresis to assess influence of the fish farming to the sediments. The sediments in the fish cage (FC) area showed anoxic conditions [redox potential of ?165 to ?213 mV and acid‐volatile sulphide‐sulphur (AVS‐S) of 0.55–1.88 mg g?1 (dry weight)] compared to the relatively oxic off‐cage area [redox potential of 72–81 mV and AVS‐S of 0.09–0.14 mg g?1 (dry weight)]. The composition of the microbial populations revealed influence of the fish feed sedimentation with higher dominance of putative sulphate‐reducing bacteria (SRB) in the FC area. Compositions of the bacterial taxa showed dominance of the Bacteroidetes group and Deltaproteobacteria. The results suggest that the fish feeds created a new suitable environment, in which reductive microorganisms such as SRB, ferric‐ion‐reducing bacteria and nitrate‐reducing bacteria can thrive. Organic load from the feed and quantity of its leftover constituents may be the key factors that influence the structure of the bacterial community in the sediments of the milkfish farms.  相似文献   
34.
ObjectiveTo determine if a nerve stimulation test (NST) could act as a monitoring technique to confirm sacrococcygeal epidural needle placement in cats.Study designProspective experimental trial in a clinical setting.AnimalsTwenty-four adult cats, scheduled for a therapeutic procedure where epidural anesthesia was indicated.MethodsUnder general anesthesia, an insulated needle was inserted through the S3-Cd1 intervertebral space guided by the application of a fixed electrical current (0.7 mA) until a motor response was obtained. The NST was considered positive when the epidural nerve stimulation produced a motor response of the muscles of the tail, whereas it was considered negative when no motor response was evoked. In the NST positive cases, 0.3 mL kg−1 of 0.5% bupivacaine was administrated before needle withdrawal. Ten minutes after injection, epidural blockade was confirmed by the loss of perineal (anal), and pelvic limbs reflexes (patellar and withdrawal).ResultsThe use of a fixed electrical stimulation current of 0.7 mA resulted in correct prediction of sacrococcygeal epidural injection, corroborated by post bupivacaine loss of perineal and pelvic limb reflexes, in 95.8% of the cases.Conclusion and clinical relevanceThis study demonstrates the feasibility of using, in a clinical setting, an electrical stimulation test as an objective and in real-time method to confirm sacrococcygeal epidural needle placement in cats.  相似文献   
35.
To investigate the impact of different dietary lipid sources on fillet composition and lipid transport, we conducted a feeding trial and evaluated the proximate composition of muscle tissue, fatty acid profiles, total cholesterol (in muscle and plasma), triglycerides, and lipoprotein concentrations in Nile tilapia, Oreochromis niloticus. Five semi‐purified diets, containing different oils (soybean – SO, corn – CO, linseed – LO, fish – FO, and olive – OO), were supplied to tilapia for 160 d. Fish fed with LO and FO diets had a lower percentage of total lipids in muscle compared with the others (P < 0.05). The highest percentage of protein was found in fish fed with FO diet (P < 0.05). The muscle fatty acid profile was influenced differently by diets (P < 0.05). The group supplemented with SO and CO had a higher concentration of 18:2n‐6, whereas the fish fed with LO diet had a higher level of 18:3n‐3 and those that received the FO diet had more 22:6n‐3 in comparison with those supplemented with vegetable oils. Plasma lipid transport was also affected by the diets: the fish fed with FO diet had higher total cholesterol and high‐density lipoprotein and lower very‐low‐density lipoprotein concentrations (P < 0.05).  相似文献   
36.
37.
The present work evaluated the use of molasses as a carbon source during the nursery rearing of Farfantepenaeus brasiliensis in a Biofloc technology system. During a 30 days trial, three replicate tanks were randomly assigned to the following treatments: 1.) molasses (with molasses addition) and 2.) control (without molasses addition). Bacteriological analysis was used to quantify the abundance of presumptive Vibrio spp. between control and molasses treatment. The concentration of this microorganism was lower in molasses compared with control. For the immunological analysis, shrimp haemolymph was collected to determine the total haemocyte count and the total protein concentration. The immunological results were not different between treatments. The performance results of shrimp reared with molasses addition showed that the survival rate (88.87 ± 6.36), the mean final weight (1.22 ± 0.38) and the specific growth rate (0.0309 ± 1.06) were significantly higher compared with control (80.5 ± 2.42; 1.03 ± 0.13; 0.0256 ± 0.97 respectively). Moreover, the addition of molasses contributed to the maintenance of water quality and lower concentration of presumptive Vibrio spp. The control presented an unstable variation of Vibrio spp. reaching values of 80 × 102 CFU/ml, while the highest result of molasses was 20 × 102 CFU/ml, confirming the beneficial effects of molasses addition.  相似文献   
38.
ObjectiveTo compare the perioperative use of analgesics and complication rates in dogs administered an erector spinae plane (ESP) block or a traditional opioid-based (OP) treatment as part of analgesic management during hemilaminectomy.Study designRetrospective cohort study.AnimalsMedical records of 114 client-owned dogs.MethodsGeneral data included demographics, duration of procedure, number of laminae fenestrated, perioperative use of steroid and non-steroidal anti-inflammatory drugs. Intra- and postoperative analgesics used in 48 hours and complications rates were compared between groups. Opioid use was expressed in morphine equivalents [ME (mg kg?1)]. Continuous data were compared using the Mann–Whitney U test and incidence of events with a Fisher's exact tests. Multiple linear regression was used to evaluate association between perioperative ME consumption (dependent variable) with other independent variables. Data are presented as median (range). Differences were considered significant when p < 0.05.ResultsGroup ESP comprised 42 dogs and group OP 72 dogs. No differences were observed in the general data. Intraoperative ME was 0.65 (0.20–3.74) and 0.79 (0.19–5.60) mg kg?1 in groups ESP and OP, respectively (p = 0.03). Intraoperative infusion of lidocaine was administered intravenously (IV) to 23.8% and 68% of groups ESP and OP, respectively (p < 0.0001). Intraoperative infusion of ketamine was administered IV to 21% and 40% of groups ESP and OP, respectively (p = 0.04). Regression analysis revealed the ESP block as the only independent variable affecting the perioperative ME consumption. Pharmacological intervention to treat cardiovascular complications was administered to 21.4% and 47.2% of dogs in groups ESP and OP, respectively (p = 0.008). There were no differences in postoperative complication rates.Conclusions and clinical relevanceESP block was associated with reduced perioperative opioid consumption, intraoperative adjuvant analgesic use and incidence of pharmacological interventions to treat cardiovascular complications in dogs undergoing hemilaminectomy.  相似文献   
39.
40.
A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with bovine respiratory syncytial virus (BRSV) infection in non-vaccinated dairy and dual-purpose cattle herds from Ecuador. A total of 2,367 serum samples from 346 herds were collected from June 2008 to February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. Presence of antibodies against BRSV was analyzed using a commercial indirect ELISA test. A logistic regression model was used to determine risk factors associated with BRSV at herd level. The individual seroprevalence against BRSV in non-vaccinated herds in Ecuador was 80.48% [1,905/2,367; 95% confidence interval (CI)?=?78.9-82.1]. The herd prevalence was 91.3% (316/346; 95% CI?=?88.3-94.3), and the intra-herd prevalence ranged between 25% and 100% (mean, 90.47%). The logistic regression model showed that the existence of bordering cattle farms, the dual-purpose farms, and the altitude of the farm (more than 2,338?m above sea level) were risk factors associated with BRSV infection. This is the first study about BRSV prevalence in Ecuador. It shows the wide spread of the BRSV infection in the country. The risk factors found will help to design effective control strategies.  相似文献   
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