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71.
GL Carroll SM Hartsfield TM Champney SC Geller EA Martinez EL Haley 《Veterinary anaesthesia and analgesia》2003,30(2):118-118
Six 3‐year‐old goats (three males and three females) weighing 60.0 ± 18 kg (mean ± SD) were used to investigate the effect of medetomidine (MED; 20 µg kg?1 IV) and its antagonism with atipamezole (ATI; 100 µg kg?1 IV) on physiologic responses (heart rate (HR; beats minute?1), respiratory rate (RR; breaths minute?1), electrocardiogram (ECG), rectal temperature (T; °C), blood pressure (oscillometric; mm Hg), sedation (SED), posture (REC), analgesia (ALG), and stress‐related hormonal and metabolic responses (epinephrine and norepinephrine (high performance liquid chromatography with electrochemical detection), cortisol (COR; µg dL?1; radioimmunoassay), glucose (GLU; mg mL?1; enzymatic colorimetric assay), and free fatty acids (modified enzymatic colorimetric assay)); each goat received ATI or SAL in random order separated by 1 week. Jugular catheters were placed for drug administration and blood sampling (10–12 mL sample?1) using a lidocaine skin block (20 mg) 2 hours prior to beginning of each trial; during this trial, goats breathed room air. Physiologic parameters were measured, SED, REC, and ALG were scored, and blood samples were collected from jugular catheters at baseline (time = ?30 minutes), 5 minutes post‐MED administration (time = ?25 minutes), 25 minute post‐MED administration and immediately prior to antagonism (time = 0 minute), and at 5, 30, 60, and 120 minutes after administering ATI or SAL. ALG was tested by clamping the withers and metacarpus with hoof testers fitted with a force transducer to measure applied isometric force (lb) (a technique used previously in goats to evaluate analgesia). Continuous variables were analyzed by Repeated Measures analysis of variance (anova ); categorical data were analyzed using a Friedman Repeated Measures anova on ranks. A p‐value of <0.05 was considered significant. If a significant difference was found, a Dunnett's pair‐wise comparison of means was conducted. Differences between ATI and SAL were examined at 5, 30, 60, and 120 minutes using a paired t‐test with a Bonferroni correction. Administration of MED resulted in a decrease in T (38.7 ± 0.3 to 34.5 ± 0.4 °C), HR (78 ± 19 to 55 ± 9), and RR (31 ± 12 to 14 ± 5) over time; an increase in mean arterial blood pressure (90 ± 19 to 132 ± 23), COR (0.254 ± 0.125 to 4.327 ± 1.233), and GLU (82.0 ± 13.2 to 255.9 ± 38.9); and changes in SED (alert to marked sedation), REC (standing to recumbent), and ALG (metacarpus = 5 ± 2 to 14 ± 0; withers = 3 ± 2 to 14 ± 0). GLU was 62–70% higher at 60 and 120 minutes and COR was 336% higher after SAL than after ATI at 120 minutes; at 30, 60, and 120 minutes, T was 4–10% higher after ATI than SAL. There were no other significant differences. REC, SED, and ALG were antagonized after ATI. ATI did not antagonize the effect of MED on HR, RR, or MAP, but stabilized T and antagonized the increase in GLU and COR. 相似文献
72.
Les teneurs en hydrates de carbone non structuraux (TNC) des racines, collets et tiges des in-dividus de la morelle jaune (Solarium elaeagnifolium Cav.) issue des bordures, champ de cotonnier et verger d'oliviers ont été déter-minées mensuellement pendant une année. Les racines et, dans une certaine mesure, les collets ont été les organes où les réserves glucidiques étaient les plus importantes. Ces glucides ont atteint leur niveau le plus bas au moment de la formation des boutons floraux. La reconstitution des réserves en TNC a lieu entre la floraison et la maturation des fruits sur une durée de 2, 4 et 5 mois pour les individus issus du champ de cotonnier, des bordures et du verger d'oliviers, respec-tivement. L'évolution des TNC est plus influencée par le stade phénologique de l'espèce que par rhumidité et la température du sol. Les implications de ces réquitals pour définir une stratégic de lutte centre la morelle jaune sont également discutées. Seasonal changes in non-structural carbohydrates in silver-leaf nightshade (Solanum elaeagnifolium Cav.) The levels of non-structural carbohydrates (TNC) in the roots, root collar and stems of S. elaeagnifolium collected from field margins, cotton fields and olive plantations were determined monthly over a period of 1 year. The roots, and to a certain extent the root collar, were the organs with the largest carbohydrate reserves. The carbohydrate level was lowest at the time of flower bud formation. There was a build-up of TNC reserves between flowering and fruit maturation over periods of 2, 4 and 5 months from plants growing in cotton fields, field margins and olive plantations respectively. Changes in TNC are influenced more by the phenological stage of the plant than by soil humidity or temperature. The implications of these findings in defining a control strategy for this weed are discussed. Saisonale Einlagerung von Kohlenwasserstoffen beim Ölweidenblättrigen Nachtschatten (Solanum eleagnifolium Cav.) Die Gehalte unstrukturierler Kohlenwasser-stoffe (TNC) des Wurzeln, des Wurzelhalses und des Sprosses von Solanum elaeagnifolium Cav. von Feldrainen, Baumwollfeldern und Olivengärten wurden monatlich über l Jahr hin bestimmt. Die Wurzeln und in bestimmten Maβe der Wurzelhals waren die Pflanzenteile, in denen die Kohlenwasserstoffe die wichtigsten Re-servesubstanzen waren; sie hatten ihr nie-drigstes Niveau zur Blütenbildung. Der Wiederaufbau dieser Reservestoffe zwischen der Blüte und der Fruchtreife dauerte bei den Pflanzen auf den Baumwollfeldern, den Feldrainen und den Olivengärten 2, 4 bzw. 5 Monate. Die Kohlenhydratbildung wurde mehrnach den Entwicklungsstadienals durch Boden feuchte und-temperatur beeinflußt. Die Aspekte dieserUntersuchungsergebnisse für die Bekämpfung dieses Unkrauts werden diskutiert. 相似文献
73.
Treatment of A. niger -inoculated onion seed with benomyl dust (1 g a.i./kg), or a foliar spray of thiram (0·4% a.i./ha) applied to plants grown from inoculated seed under temperate (UK) conditions reduced the incidence of A. niger in harvested crops. Treatment of naturally contaminated Sudanese onion seed with a benomyl + thiram mixture at a rate of 2·5 + 2·5 g a.i./kg or soaking the seed in hot water (15 min at 60°C) reduced the incidence of black mould on bulbs grown in the Sudan in field soil that had not previously been used for onion production. The seed treatments were less effective in crops produced in fields regularly used for onion production. However, incubation of harvested bulbs in moist chambers showed that damage to the internal storage tissue of onion bulbs caused by A. niger was reduced by seed treatment. 相似文献
74.
75.
AIMS: To describe and evaluate the current practices used to manage and prevent facial eczema (FE) in North Island dairy herds, and determine the within-herd prevalence of cows with elevated activities of gamma glutamyl transferase (GGT), and with concentrations of Zn in serum <18?μmol/L.METHODS: Between January and May 2014, 105 herd managers from throughout the North Island of New Zealand were invited to participate in the study when regional spore counts for Pithomyces chartarum started to rise towards 30,000 spores/g pasture. Managers selected 10 representative cattle that were weighed and blood-sampled by the herd veterinarian. Blood samples were analysed for concentrations of Zn in serum and GGT activity. Pasture samples were also collected and submitted for spore count estimation. Finally a survey of farm management practices relating to prevention of FE was completed by the herd manager. A mixed-effects logistic regression model was used to determine associations between herd-level and cow-level explanatory variables and the probability of a cow having a concentration of Zn in serum <18?µmol/L.RESULTS: Of the 1,071 cows tested, 79 (7.3 (95% CI=5.8–9.0)%) had GGT activity in serum >300?IU/L, and 35/106 (33 (95% CI=24.2–42.8)%) herds had ≥1 of the 10 cows sampled with GGT activity >300?IU/L. Of the 911 cows that were being treated with Zn, concentrations of Zn were between 18–35?μmol/L in 398 (43.6 (95% CI=40.4–46.9)%) cows, were >35?μmol/L in 32 (3.5 (95% CI=2.4–4.1)%) cows, and <18?μmol/L in 479 (52.6 (95% CI=49.3–55.9)%) cows. After adjusting for the confounding effect of region, the odds of a cow having concentrations of Zn in serum <18?μmol/L were 5.5 (95% CI=1.1–29) times greater for cows supplemented with zinc in water compared with those supplemented by drenching. Of the 105 herd managers, 103 (98%) stated that they had access to regional spore count data, but only 35/105 (33%) reported that they measured spore counts on their own farm. Overall, 98/105 (93%) managers reported that they had some form of FE management programme in place. Fungicides were used on their own or in combination with zinc treatments in 10 herds, ZnSO4 in water troughs was used in 68 herds, oral drenching with ZnO in nine herds, and ZnO supplied in-feed in 26 herds. Estimated daily dose rates of zinc were less than that required to treat a 400?kg cow on 42/68 farms that administered ZnSO4 in the water or ZnO as a drench.CONCLUSION AND CLINICAL RELEVANCE: This study has shown that FE management on dairy farms in the North Island of New Zealand could be substantially improved. It is likely that improved FE management would occur if herd managers were provided with more feedback on the success (or otherwise) of their FE management programmes. 相似文献
76.
AIMS: To determine whether the application of lime or nitrogen to pasture affected the spore counts of Pithomyces chartarum.MATERIALS AND METHODS: The lime application studies were undertaken on a spring-calving, pasture-based, commercial dairy farm near Te Awamutu, New Zealand. On 6 November 2012, five randomly selected paddocks were split into three equal sections. In two of the sections, lime was applied at either 1.5 or 2.5?t/ha, and the central section was left as an untreated control. Each section was sampled for spore counting weekly from 16 January to 15 May 2013.Starting in January 2013, five other randomly selected paddocks were monitored for spore counts. On 20 March 2013 the average spore counts in three paddocks were >100,000 spores/g of pasture. These paddocks were then divided into three equal sections and lime was applied as described above. Spore counting in each section continued weekly until 15 May 2013.The nitrogen application study was carried out on three commercial dairy farms near Te Awamutu, New Zealand. Two randomly selected paddocks on each farm were divided into three equal sections and, on 20 December 2012, nitrogen in the form of urea was applied at either 50 or 80?kg urea/ha to two of the sections; the central section remained as an untreated control. Each section was sampled for spore counting weekly from 16 January to 15 May 2013.RESULTS: Following pre-summer lime application, treatment at 1.5 or 2.5?t/ha did not affect spore counts over time compared with the control section (p>0.26). Similarly following autumn lime application, treatment at 1.5 or 2.5?t/ha did not affect spore counts over time compared with the control section (p>0.11). Following nitrogen application median spore counts remained <20,000 spores/g pasture throughout the trial period and there was no effect of treatment on spore counts over time (p>0.49).CONCLUSION: This study found that application of lime before the risk period for facial eczema, in November, application of lime after a spore count rise, in March, or urea application in December did not affect changes in number of spores produced by P. chartarum.CLINICAL RELEVANCE: This study does not support previous suggestions that fertilising pasture with lime or urea could alter the spore counts of P. chartarum. Fertiliser use does not provide an alternative to, or support, conventional methods of facial eczema control such as zinc prophylaxis or treatment of pasture with fungicides. 相似文献
77.
CR Jimenez JL de Azevedo RG Silveira J Penitente‐Filho EL Carrascal‐Triana AM Zolini VR Araujo CAA Torres WG Gonçalves 《Reproduction in domestic animals》2016,51(3):435-444
This study aimed at assessing the effect of different concentrations of the growth factor similar to insulin 1 (IGF‐1) in the development, survival and ultrastructure of the bovine preantral follicles cultured in situ. Fragments of bovine ovarian cortical tissue were cultured during 1 and 7 days in 1 ml of α‐MEM+, supplemented with different concentrations of human recombinant IGF‐1 (0, 30, 70 and 100 ng/ml), in an incubator at 37°C and 5% of CO2 in 24‐well plates with total replacement of the medium every 2 days. Non‐cultured ovarian fragments (control) and ovarian fragments cultured during 1 and 7 days were processed for classic histology, mechanical isolation and electron transmission microscopy (ETM). Parameters such as normality, viability, activation, development, diameter and ultrastructure were evaluated. All statistical analyses were carried out using sas Version 9.2. The results showed that the percentage of follicles morphologically normal in the IGF‐1 30 ng/ml treatment was similar to the fresh control (p > 0.05) both on the day 1 and on the day 7 of in vitro culture. In the viability analysis, the cultured treatments maintained the percentage of viable follicles during the entire culture period (p > 0.05). After 7 days of culture, the IGF‐1 30 ng/ml treatment showed higher percentages of developing follicles (48.33%) than those of the fresh control (22.22%) and the cultured treatments (p < 0.05). Also, after 7 days of culture, IGF‐1 30 ng/ml presented a higher follicular diameter when compared to the control and other concentrations of IGF‐1 tested. Ultrastructurally, the non‐cultured control and IGF‐1 30 ng/ml, after 7 days of culture, showed conserved oocytes, nuclei and organelles. Hence, it is concluded that IGF‐1 30 ng/ml was the most efficient concentration for the development of bovine preantral follicles cultured in vitro. 相似文献
78.
A. GOUDAH K. ABO EL‐SOOUD J.‐H. SHIM H.‐C. SHIN A. M. ABD EL‐ATY 《Journal of veterinary pharmacology and therapeutics》2008,31(5):399-405
The target of the present study was to investigate the plasma disposition kinetics of levofloxacin in stallions (n = 6) following a single intravenous (i.v.) bolus or intramuscular (i.m.) injection at a dose rate of 4 mg/kg bwt, using a two‐phase crossover design with 15 days as an interval period. Plasma samples were collected at appropriate times during a 48‐h administration interval, and were analyzed using a microbiological assay method. The plasma levofloxacin disposition was best fitted to a two‐compartment open model after i.v. dosing. The half‐lives of distribution and elimination were 0.21 ± 0.13 and 2.58 ± 0.51 h, respectively. The volume of distribution at steady‐state was 0.81 ± 0.26 L/kg, the total body clearance (Cltot) was 0.21 ± 0.18 L/h/kg, and the areas under the concentration–time curves (AUCs) were 18.79 ± 4.57 μg.h/mL. Following i.m. administration, the mean t1/2el and AUC values were 2.94 ± 0.78 h and 17.21 ± 4.36 μg.h/mL. The bioavailability was high (91.76% ± 12.68%), with a peak plasma mean concentration (Cmax) of 2.85 ± 0.89 μg/mL attained at 1.56 ± 0.71 h (Tmax). The in vitro protein binding percentage was 27.84%. Calculation of efficacy predictors showed that levofloxacin might have a good therapeutic profile against Gram‐negative and Gram‐positive bacteria, with an MIC ≤ 0.1 μg/mL. 相似文献
79.
V.O. CRAMPTON D.A. NANTON K. RUOHONEN P.‐O SKJERVOLD A. EL‐MOWAFI 《Aquaculture Nutrition》2010,16(4):437-446
To date aquaculture’s reliance on dietary marine sources has been calculated on a fish weight‐to‐weight basis without considering the absolute amounts of nutrients but this approach neglects the often considerable differences in the nutritional value of fish. We propose simple nutrient‐to‐nutrient‐based dependency measures that take into account these nutritional differences. In the first study reported here, individually tagged Atlantic salmon (Salmo salar) were reared in seawater supplied tanks with feed collection facilities. In the second, commercial net pens were used to grow over 200 000 fish. For both studies, a low marine ingredient feed containing approximately 165 g kg?1 fishmeal was compared to a control feed (approx 300 g kg?1 fishmeal) whilst fish oil inclusion was less markedly reduced. The low marine feeds supported similar growth and feed efficiency compared to the control feeds. With the low marine ingredient feeds, the weight of salmon protein and lipid produced through growth exceeded the weight of marine protein and lipid consumed by the fish meaning that salmon farming can be a net producer of fish protein and oil. The amount of n‐3 long‐chain polyunsaturated fatty acids deposited was sufficient to meet current recommendations from human health organizations. 相似文献
80.
The main objectives of this study were to evaluate the effect of partial and total replacement of fish meal (FM) protein by cow pea seed meal (CPSM) protein in practical diets on growth performance, feed utilization, and body composition of Nile tilapia, Oreochromis niloticus (L.). Fish of an average initial weight of 4.6 ± 0.2 g were stocked in 15 glass aquariums (80 L each) at a rate of 15 fish per aquarium. FM protein (30% of the diet) was used as the sole source of animal protein in the control diet. Percent replacement of FM by CPSM on the basis of crude protein were as follows: 0% (control diet A), 25% (diet B), 50% (diet C), 75% (diet D), and 100% (diet E). Diets were fed to fish at a rate of 4% of the total fish biomass daily, for a period of 16 wk. The results of this study revealed that the fish fed control diet A (100% FM) had the best average final body weight, specific growth rate (SGR %/d), weight gain (g/fish), weight gain %, while the poorest results for all parameters were obtained with fish fed diet E (100% CPSM). The same parameters of fish fed diets B (25% CPSM) and C (50% CPSM) were not significantly different (P > 0.05) from those of fish fed the control diet A. Feed utilization parameters of fish fed diets A, B, C, and D were better than for diet E. Proximate composition of whole‐body moisture and ash contents were not significantly different (P > 0.05) among all experimental diets and control diet. Whole‐body protein contents for fish fed diets B and C were superior to the control diet A. Incorporation of CPSM in the diets significantly increased whole‐body fat content. Incorporation of CPSM in the diets significantly decreased apparent digestibility coefficient of crude protein crude fat and energy. Diets B and C were not significantly different from control diet A. Therefore, these findings suggest that up to 50% of FM protein can be replaced by CPSM protein in Nile tilapia diets without any adverse effects on growth performance, feed utilization, body composition, and digestibility. 相似文献