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21.
Isolation distance is the main barrier to crop-to-crop gene-flow. A 3-year study assessed the maximum potential outcrossing under field conditions between two wheat cultivars (Triticum aestivum L.) and between wheat and durum wheat (Triticum turgidum L. var. durum). Outcrossing was measured by seed set on emasculated recipient plants placed at four sides with different distances from a 3 m × 3 m T. aestivum (cultivar Chinese Spring) pollen source. Frequencies of seed set at 0 m distance were 45% (37–56%) for T. aestivum cultivars and 18% (5–30%) with T. turgidum. These values agree with hybridization in non-limiting pollen conditions measured by manual crosses in greenhouse. The number of pollen grains and the outcrossing frequencies decreased at increasing distances influenced by the prevailing wind direction. Under semiarid conditions of this assay, viable pollen was found 14 m from the pollen source, with a maximum distance of 8 m at which cross-pollination decreases below 1%. Ambient conditions affect pollen viability, hybridization and pollen dispersal. Data presented in this paper emphasize the major role played by environmental conditions in outcrossing. Data obtained in one area may therefore not coincide with the prevailing situation in different locations and climates.  相似文献   
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Lolium rigidum is the most prevalent and damaging grass weed of winter cereals in Spain. L. rigidum infestations are frequently treated with herbicides and, consequently, populations have evolved resistance. The objective of this study was to determine the extent and frequency of herbicide resistance in L. rigidum populations in Spain to the selective herbicides chlortoluron, diclofop-methyl and chlorsulfuron, commonly used for its control in-crop, and to glyphosate. The response to these herbicides was evaluated on 123 accessions surveyed randomly across cereal cropping areas of the regions of Castile and León, Catalonia and Andalusia. The fresh weight and the frequency of undamaged plants were calculated for each accession and herbicide. At the regional level, higher frequencies of accessions displaying resistance occurred in Catalonia, an intensively cropped region with a greater herbicide selection pressure. Of concern is that in this region the 60% of the accessions displayed some level of resistance to the ALS-inhibiting herbicide chlorsulfuron. The 6.9% of the accessions found in Castile and León with some resistance to glyphosate could also indicate an incipient problem of resistance to this herbicide. For the other herbicides and regions the majority of the accessions remained susceptible. The possible mechanisms of herbicide resistance development in L. rigidum accessions (target-site versus non-target-site resistance) and their variation among regions was discussed. This study can be used to generate herbicide resistance-management schemes for farmers, based upon the herbicide the site and the potential for resistance development.  相似文献   
23.

Objective

The aim of this study was to validate the Italian version of the UNESP–Botucatu Unidimensional Composite Pain Scale (UCPS-IV) for assessing postoperative pain in cattle.

Study design

Video analysis and psychometric testing.

Animals

A total of 40 Nellore cattle, age 2–3 years, weighing 365 ± 51 kg.

Methods

An English version of the scale was translated to Italian and back translated to English to ensure semantic equivalence. A total of four Italian observers and the researcher who developed the original scale (considered as the gold standard) analysed videos of 40 cattle previously subjected to orchiectomy (recorded for each cattle at four predetermined timepoints during the perioperative period) unaware of the videos’ timepoint. They assigned a pain score [ranging from no pain (0) to severe pain (10)] using the Italian version of the scale and verified the need for analgesic treatment for each animal. The obtained scores were subjected to psychometric validity, responsiveness and reliability tests.

Results

The factor analysis of the scale resulted in a one-factor solution. Significant changes in pain scores in response to surgery and analgesics confirmed not only the content and construct validity, but also responsiveness. The agreement between the researcher who developed the original scale and the blinded observers and the correlation between the pain scores determined by the scale and those determined by three classical unidimensional pain scales confirmed criterion and concurrent validity. Internal consistency of the scale was excellent. Inter- and intrarater reliability ranged from moderate to good and from moderate to very good for all scale items, respectively, supporting reproducibility and stability. The cut-off point for rescue analgesia calculated by the receiver operating characteristic curve was > 3.

Conclusions and clinical relevance

The results confirm that the UNESP–Botucatu UCPS-IV appears to be a valid and reliable tool for the assessment of postorchiectomy pain in the bovine species. The determination of a cut-off point for rescue analgesia is also helpful for guiding analgesic therapy.  相似文献   
24.

Background

Cats with hypertrophic cardiomyopathy (HCM) and congestive heart failure (CHF) can have resolution of both left ventricular hypertrophy and CHF.

Objectives

To describe the clinical characteristics of cats with transient myocardial thickening (TMT) and CHF compared with a control population of cats without resolution of HCM.

Animals

A total of 21 cats with TMT, 21 cats with HCM.

Methods

Retrospective study. Clinical records at 4 veterinary centers were searched for TMT cases and a control group of cats with HCM and CHF. TMT was defined as initial maximal left ventricular wall thickness (LVWT) ≥6 mm with left‐sided CHF, with subsequent resolution of CHF, reduction in left atrium/aorta (LA/Ao), and LVWT<5.5 mm. HCM was defined as persistent LVWT ≥6 mm.

Results

Cats with TMT were younger (2 [0.4–11.4] years) than cats with HCM (8 [1.6–14] years) (P < 0.0001), and antecedent events were more common (15/21 versus 6/21, respectively) (P = 0.01). In cats with TMT, LVWT normalized from 6.8 [6.0–9.7] mm to 4.8 [2.8–5.3] mm and LA/Ao decreased from 1.8 [1.6–2.3] to 1.45 [1.2–1.7] after a mean interval of 3.3 (95% CI: 1.8–4.7) months. CHF recurred in 1 of 21 TMT and 15 of 21 cats with HCM. Cardiac treatment was discontinued in 20 of 21 cats with TMT and 0 of 21 HCM cats. All cats with TMT survived, whereas 8 of 19 cats with HCM died during the study period.

Conclusions and Clinical Importance

TMT occurs in younger cats, and antecedent events are common. The prognosis is better in cats with CHF associated with TMT than HCM.  相似文献   
25.
O bjectives : Dyspnoea is an unspecific severe presenting sign, which can be life threatening and requires prompt treatment. Dyspnoeic cats often have significant underlying disease. Underlying aetiologies in cats that presented with dyspnoea were reviewed, and associations with patient signalment and outcome were investigated.
M ethods : The case records of 90 dyspnoeic cats were retrospectively reviewed and separated into different groups depending on aetiology (cardiac, respiratory, neoplastic and trauma). Duration of clinical signs, presentation, hospitalisation length and survival were analysed.
R esults : Cardiac (38 per cent), respiratory (32 per cent) and neoplastic (20 per cent) diseases were common causes of feline dyspnoea. Cats with respiratory causes had longer duration of clinical signs (P<0·001) before presentation. Cats with neoplasia were significantly older (P<0·001). No significant difference in respiratory rates was present between the groups (P = 0·154). High heart rates (P<0·001) and abnormalities on cardiac auscultation were more likely in the cardiac group.
Clinical Significance: Frequent causes of dyspnoea in cats were cardiac disease followed by respiratory causes and neoplastic conditions. Heart rate on presentation and presence of heart murmurs or gallops are useful to identify cardiac causes. Improved proportion surviving was found in the respiratory group (P = 0·027), whereas cats with neoplasia had the worst outcome.  相似文献   
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ObjectiveTo test the effectiveness and safety of tramadol plus metamizole combined or not with a non-steroidal anti-inflammatory drug (NSAID) for treating moderate to severe chronic neoplastic pain in dogs, and its impact on quality of life (QL).Study designProspective, uncontrolled, open-label, clinical study.AnimalsSixty nine client-owned dogs with multiple forms of cancer and visual analog scale (VAS) pain score ≥40 after receiving NSAIDs for at least 7 days.MethodsThe MN group received metamizole + NSAID, MNT group received metamizole + NSAID + tramadol and MT group received metamizole + tramadol. Pain was scored by the 0 to 100 mm VAS (0 = no pain, 100 = worst pain) and analgesic therapy was considered effective if 25 mm differences in VAS scores were observed between day 0 and the follow ups. The QL was evaluated according to a 0 to 36 scoring method for dogs (0 = worst, 36 = best) and side effects were recorded. Data were registered at day 0 (baseline) and at the first and second follow ups (7 and 14 days after day 0, respectively).ResultsThe MN group had less analgesia at day 7 (25%) and day 14 (42%) than MNT (59%, p = 0.0274; 76%, p = 0.0251, respectively) and MT groups (69%, p = 0.0151; 81%, p = 0.0341, respectively). The QL scores were lower in the MN group at the first (score 23) and second follow up (score 26) than in MNT (27, p = 0.0847; 30, p = 0.0002) and MT (28, p = 0.0384; 31, p = 0.0001) groups. Side effects were more commonly observed in the MN group (87%) than in MNT (24%, p < 0.0001) and MT groups (25%, p = 0.0003) at the first follow up.Conclusions and clinical relevanceTramadol plus metamizole combined or not with NSAID were well tolerated and clinically effective to treat moderate to severe pain in dogs with cancer and improved QL.  相似文献   
30.
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