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101.
Eva-Maria Halbauer Valentina Bohinec Melanie Wittenberger Karin Hansel-Hohl Stephan Gaubitzer Eva M. Sehr 《Euphytica》2017,213(6):120
Agro-biodiversity is currently experiencing severe genetic erosion due to mankind’s unsustainable activities. Because of initiatives following the goal of the conservation of biological diversity, so far seven million crop accessions are being conserved ex situ in gene banks worldwide. Many of these accessions are landraces being rich in gene diversity, silently awaiting their proper characterisation. This is a very critical part of any long-term strategy to enhance the productivity and resilience of crops and agricultural systems and—most importantly—to ensure the preservation of our cultural and biological heritage. In this study of an ex situ germplasm evaluation we analysed 27 flax (Linum usitatissimum L.) accessions originating in the Alpine region, provided by five local gene banks/providers. Based on genomic microsatellite markers (gSSRs), a varying extent of accession-specific gene diversity (expected heterozygosity, HE) was revealed ranging from 0.05 to 0.51. Admixture of individuals between accessions was uncovered, pointing towards past processes related to gene bank management activities (e.g. intentional selection, unintentional cross-pollination during regeneration) or towards the evolution of the landrace itself (e.g. same regional origin, traditional naming), highlighting the co-existence of cultural and biological diversity. Such an genetic analysis of accessions stored ex situ not only produces valuable agronomic and breeding data, but also is useful for the clarification of past processes leading to duplicates within and between collections or mislabelling, contributing to the potential for rationalisation of collections, which in turn can help ensure that the limited resources available for regeneration are used most efficiently and effectively. 相似文献
102.
S S Nicholson B M Olcott E A Usenik H W Casey C C Brown L E Urbatsch S E Turnquist S C Moore 《Journal of the American Veterinary Medical Association》1989,195(3):345-346
A phalaris grass (Phalaris caroliniana) caused neurologic signs and lesions in cattle and sheep. The sheep were hyperexcitable and uncoordinated, with severe muscle twitching, stiff gait, and head nodding. The cattle were thin, nervous, and ataxic. One feature of chronic phalaris toxicosis in these cases was onset of signs weeks or months after removal of the animals from the forage. 相似文献
103.
Luzzago C Frigerio M Piccinini R Daprà V Zecconi A 《Veterinary journal (London, England : 1997)》2008,177(2):236-241
To support a voluntary disease control program, this study aimed to develop an integrated scoring system for the risk assessment of bovine viral diarrhoea virus (BVDV) infection in dairy herds in Northern Italy. Sixty-two dairy herds were classified according to their BVDV serological status. Farmers were interviewed using a questionnaire on potential BVDV risk factors. Scores were used to define risk levels for factors related to (1) BVDV introduction (through livestock trade, attendance of animals at shows/exhibitions and grazing common pasture), (2) within-herd spread of BVDV and (3) the results of initial serological testing. The calculated odds ratios were significant for all categories, except for livestock trade. The application of the screening test, the questionnaire and the related risk assessment showed this to be a practical approach to predicting BVDV herd status. 相似文献
104.
105.
Barbara Ambros Maria Valentina Carrozzo Teela Jones 《Veterinary anaesthesia and analgesia》2018,45(4):452-458
Objective
To compare time to desaturation after induction of anesthesia following administration of oxygen via face mask or flow-by for 3 minutes.Study design
Randomized crossover study.Animals
A group of six healthy adult dogs weighing 15.0 ± 3.4 kg.Methods
Dogs were anesthetized twice separated by 14 days. Intramuscular administration of dexmedetomidine (4 μg kg?1), acepromazine (0.01 mg kg?1) and butorphanol (0.2 mg kg?1) provided sedation for percutaneous insertion of a catheter into the tracheal lumen. The tip was advanced to the thoracic inlet and position confirmed using fluoroscopy. Using a sample aspiration rate 200 mL minute?1, inspired (FIO2) and end-tidal oxygen (Fe′O2) were measured. Oxygen (100 mL kg?1 minute?1) was delivered into a circle delivery system and administered to the dog for 3 minutes via face mask or flow-by from the circle Y-piece 2.5 cm from the nares. Then, propofol was administered to induce anesthesia and apnea. A pulse oximeter (lingual probe) measured hemoglobin saturation (SpO2). At SpO2 90% (desaturation point), an endotracheal tube was inserted to allow administration of oxygen and artificial ventilation. Arterial blood and data were collected at baseline (before oxygen administration), 5 seconds after induction of anesthesia, and every 30 seconds until the desaturation point was reached. Data were analyzed using an unpaired and paired t test with (p < 0.05).Results
FIO2, Fe′O2 and PaO2 (mean ± standard deviation) were significantly higher after mask preoxygenation [89.7 ± 5.5%, 83.0 ± 7.6% and 394 ± 112 mmHg (52.4 ± 14.9 kPa)] compared with flow-by [30.0 ± 5.4%, 22.7 ± 3.8% and 133 ± 22 mmHg (17.7 ± 2.9 kPa)], respectively. Time to desaturation was significantly longer after mask treatment compared with flow-by (187 ± 67 versus 66 ± 17 seconds).Conclusions and clinical relevance
Mask preoxygenation provided longer time to desaturation compared with the flow-by technique tested. 相似文献106.
Maria Valentina Carrozzo Jane Alcorn Barbara Ambros 《Veterinary anaesthesia and analgesia》2018,45(6):831-838
Objective
To determine the pharmacokinetics and effects on thermal thresholds (TT) of two fentanyl constant rate infusions in awake cats.Study design
A blinded, randomized crossover study.Animals
A group of six healthy female cats, aged 3 ± 1 years, weighing 4.1 ± 0.7 kg.Methods
Skin temperature (TSKIN) and TT were evaluated using a wireless TT device. TSKIN, TT, sedation score (SS) and blood samples were collected before an intravenous loading dose (LD; over 5 seconds) and at specific time points during (360 minutes) and after infusion. Each cat was administered two treatments: fentanyl (LD 3 μg kg?1, infusion 3 μg kg?1 hour?1; treatment F3) or fentanyl (LD 5 μg kg?1, infusion 5 μg kg?1 hour?1; treatment F5). SS between treatments was analyzed using a Kruskal–Wallis test. Statistical analysis of TT and TSKIN was performed using analysis of variance with appropriate post hoc test (p < 0.05).Results
TSKIN did not vary over time for each treatment. SS did not differ between treatments. TTs were significantly higher than baseline at 15 minutes after LD for F3 and F5. TT was significantly increased at 30, 90, 120, 180 and 300 minutes in treatment F5 but not in F3. Plasma fentanyl concentrations decreased rapidly in both treatments over the first 30 minutes after infusion. The terminal half-life was 3.31 (2.93–4.41) hours for F3 and 3.67 (3.39–4.32) hours for F5 (median, range). Systemic clearance for treatments F3 and F5 was 1.95 (1.46–2.44) and 2.25 (1.98–2.47) L hour?1 kg?1 (median, range), respectively. Plasma concentrations <1.84 ng mL?1 were not associated with a significant increase in TT.Conclusions
and clinical relevance A fentanyl infusion rate of 5 μg kg?1 hour?1 increased TT during the infusion period. Effects on TT were lost rapidly with cessation of the infusion. 相似文献107.
108.
Sergei Amstislavsky Eugeny Brusentsev Elena Kizilova Valentina Mokrousova Valeria Kozhevnikova Tatyana Abramova Irina Rozhkova Sergey Naidenko 《Reproduction in domestic animals》2018,53(5):1219-1226
The Far‐Eastern wildcat (Prionailurus bengalensis euptilurus) is a rare and poorly investigated nondomestic felid species. An attempt of freezing and cryopreserving Far‐Eastern wildcat spermatozoa in CaniPlus Freeze (CPF) medium is reported. Sperm was collected by electroejaculation from five adult Far‐Eastern wildcat captive‐born males. Epididymal spermatozoa from five adult randomly bred domestic cat males were used as a reference. The viability of frozen–thawed spermatozoa evaluated by double staining with SYBR Green I and PI followed by the subsequent confocal laser scanning microscopy (CLSM) was 38.2% ± 3.0% for the domestic cat and 38.0% ± 10.2% for the Far‐Eastern wildcat. The motility of frozen–thawed spermatozoa was 30.8% ± 9.8% for the domestic cat and 33.7% ± 15.1% for the Far‐Eastern wildcat. Sperm morphology was assessed by light microscopy. The total percentage of normal spermatozoa after freezing and thawing was 51.9 ± 5.9 for the domestic cat and 55.0% ± 6.4% for the Far‐Eastern wildcat. Defects of flagella were the most frequently observed abnormalities in both species (32.2% ± 4.8% and 30.8% ± 4.4% of all reported anomalies for the domestic cat and Far‐Eastern wildcat, respectively). Domestic cat epididymal and Far‐Eastern ejaculatory spermatozoa fertilized in vitro‐matured oocytes of the domestic cat (30.0% ± 5.5% and 35.5% ± 15.0%, respectively). Taken together, these results suggest that the freezing of Far‐Eastern wildcat spermatozoa with CPF medium is a suitable method for Felidae cryopreservation. 相似文献
109.
110.
Transdermal absorption of four lidocaine (L) patches (5%) was compared with the transdermal absorption of L cream (5%) to evaluate the pharmacokinetics of the two formulations applied on the same anatomic region under dressing in eight horses. The animals were also assessed for antinociceptive effect after removal of the patches and cream, using a psychophysical method visual analog scale, by pricking the patient's skin to test the response to pain. Horses were randomly assigned to four treatment groups: in groups I and II, four L patches were applied for a period of 24 hours with and without alcohol precleaning, respectively; in group III, 5% L cream was applied every 2 hours over a 24-hour period on the same anatomic site. Group IV was the control. No clinical side effects were noted with either formulation. L was detectable in plasma 6 to 24 hours after application of the patches, and the highest plasma concentrations were reached between 12 and 18 hours. The use of alcohol to preclean the skin appeared to reduce the transdermal drug absorption over time. After L cream application, the peak plasma drug concentration occurred at 24 hours. Nociception assessment after L patch or L cream application showed a decreased response when the L cream was used. The results of this study showed that there was minimal absorption from the L patches compared with the L cream in horses. Also, the L cream treatment reduced significantly the intensity of nociception quality as measured by the visual analog scale. 相似文献