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141.
Diego E. Gomez Nicola C. Cribb Luis G. Arroyo André Desrochers Gilles Fecteau Sylvain Nichols 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(10):965-969
Endoscopic removal of esophageal and ruminal foreign bodies was successfully performed in 5 Holstein-Friesian calves under sedation or general anesthesia by using an electrocautery snare or a wire-guided Dormi basket. This report describes the endoscopic manipulations, treatment, and outcomes of esophageal foreign body removal in these calves. 相似文献
142.
Inmaculada Moreno Julio Álvarez Nerea García Santiago de la Fuente Irene Martínez Eloy Marino Alfredo Toraño Joaquin Goyache Felipe Vilas Lucas Domínguez Mercedes Domínguez 《Veterinary parasitology》2014,199(3-4):264-267
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections. 相似文献
143.
I.E. Pérez-González M.G. Prado-Ochoa M.A. Muñoz-Guzmán V.H. Vázquez-Valadez A.M. Velázquez-Sánchez B.L. Avila-Suárez C. Cuenca-Verde E. Angeles F. Alba-Hurtado 《Veterinary parasitology》2014,199(3-4):235-241
The effects of six new synthetic carbamates on fully engorged females of four Rhipicephalus microplus strains (one reference strain susceptible to conventional ixodicides, two strains multiresistant to ixodicides and one tick field isolate) were compared. In addition, the effect of two other new synthetic carbamates was tested on larvae from the same strains. The first six tested carbamates reduced egg laying and inhibited egg hatching in the four studied strains (P < 0.05). Compared with untreated females, the eggs produced by the treated engorged female ticks of all strains had a dark, dry, opaque appearance and were less adherent. The remaining two tested carbamates induced larval mortality in all of the evaluated strains. The three studied R. microplus strains displayed 50% resistance ratios (RR50) of less than 2 when compared to the susceptible reference strain. These results demonstrate that both carbamates with a larvicidal effect and carbamates that inhibit egg laying and embryo development are efficacious against tick strains that are resistant to commercial ixodicides, no cross resistance was observed. 相似文献
144.
Jacopo Guccione Diego Piantedosi Antonio Di Loria Vincenzo Veneziano Paolo Ciaramella 《Journal of Equine Veterinary Science》2014
The heart rates (HR) and rhythms of 15 healthy donkeys of various ages, both sexes, and various breeds were analyzed throughout 24-hour Holter monitoring. The animals were evaluated at rest in their daily environment without the presence of investigators causing stress, using a three-channel digital Holter recorder. Analysis revealed a maximal HR range from 62.5 to 93.7 beats/min (mean, 72.50 ± 7.51 beats/min), whereas the minimal HR ranged from 29.7 to 42.2 beats/min (mean, 34.90 ± 4.22 beats/min). The daily mean HR was 47.55 ± 3.70 beats/min. The daytime mean HR was 49.39 ± 2.77 beats/min, whereas the night time rate was 46.22 ± 4.38 beats/min. Sinus bradycardia and sinus tachycardia were detected in 7 and 10 of 15 studied donkeys, respectively. Cardiac dysrhythmias due to high vagal tone such as sinoatrial heart block and second-degree atrioventricular heart block were occasionally recorded in 1 and 3 donkeys, respectively. A higher mean HR and fewer cardiac dysrhythmias were observed in donkeys than in horses and ponies at rest. These findings could be justified by differences in the autonomic nervous system tone. 相似文献
145.
EA Ordoñez‐Leon H Merchant A Medrano M Kjelland S Romo 《Reproduction in domestic animals》2014,49(2):306-314
The aim of this study was to quantify the content of lipid droplets in bovine oocytes and embryos from Bos indicus (Bi), Bos taurus (Bt) and Bos indicus × Bos taurus (Bi × Bt). Oocytes were aspirated post‐mortem and subjected to in vitro maturation, in vitro fertilization and in vitro development; the medium employed at each stage (TCM‐199, TALP, SOF) was supplemented with (i) serum replacement (SR), (ii) foetal calf serum (FCS) or (iii) oestrous cow serum (ECS). The structure and distribution of the lipid droplets were established using electron microscopy, but were quantified using an optical microscope on semi‐fine toluidine blue‐stained sections. The highest percentage of embryos corresponded to those produced with FCS and ECS, which differed from embryos generated with SR (p < 0.05). The highest percentage of morulae and the lowest percentage of blastocysts were obtained with the SR supplement (p < 0.05). The oocytes cultured in FCS demonstrated a higher number of lipid droplets compared to those cultured in SR and ECS (p < 0.05). Less accumulation of lipids was observed in embryos supplemented with SR. The lowest and highest numbers of lipid droplets in oocytes corresponded to the Bi and Bt strain, respectively. The lowest amount of lipid droplets in embryos was observed in Bi (p < 0.05). In conclusion, supplementation of the in vitro development culture medium (synthetic oviduct fluid) with a synthetic substitute serum produced similar results in terms of embryo development compared to those obtained with FCS, but a decreased degree of lipid droplet accumulation was observed in the in vitro‐cultured embryos. 相似文献
146.
147.
Cristina Rodríguez-García Fernando Montes Federico Ruiz Isabel Cañellas Pilar Pita 《European Journal of Forest Research》2014,133(5):895-904
Sustainable forest management requires knowledge of forest structure and dynamics as well as an estimation of growing stock. The forest inventory provides the data for estimating stand variables. The measurement device MU2005-01738, patented by the Center for Forest Research (INIA-CIFOR), provides stereoscopic hemispherical images which can allow the 3D restoration of the stand around the sampling point. The aim of this study is to develop a methodology for forest stand mapping as well as tree diameter and height measurement along with volume estimation from the stereoscopic hemispherical images provided by the MU2005-01738. Using the MU2005-01738, Eucalyptus globulus Labill. plantations were sampled. Distance, diameter, height and volume were derived from the stereoscopic hemispherical images of 30 trees located at distances ranging from 0 to 15 m from the device. These variables were then compared with field measurements and the estimation errors analyzed. The (root-mean-squared error) RMSE was 0.23 m (8.95 %) for tree position and 1.51 cm (10.43 %) for diameter at breast height measurement at distances of less than 8 m. In the case of stem height and individual tree volume estimation, the RMSE was 2.59 m (23.05 %) and 0.025 m3 (17.94 %), respectively. The analysis of measurement errors indicated that the measurement precision decreases beyond 8 m from the device as well as for directions close to the baseline (the line between the optical centers of the two images), whereas the precision was highest for directions near to the line which is perpendicular to the base line. Future research should focus on improving measurement accuracy and possible applications in the field of forestry of the techniques presented in this study. 相似文献
148.
Guillermo Riesco Muñoz Óscar Santaclara Estévez Juan Gabriel Álvarez González Esther Merlo Sánchez 《European Journal of Forest Research》2014,133(4):623-630
The aim of this study was to establish the sources of variation in maritime pine wood properties related to appearance and strength, because of the importance of this wood in the sawing industry in Galicia (NW Spain). Ten trees from each of ten plots of the species (i.e., 100 trees) growing in Galicia were felled and sawn to produce the structural planks required for studying the presence of external strength-reducing characteristics. The planks were sampled from the basal logs to 16 m height in the stems, yielding cross sections of target dimensions 100 × 40 mm to 200 × 200 mm. We propose a model in which individual tree height and dominant height are used to predict the knottiness of planks from trees in mature stands. The abundance of externally visible knots on faces and edges of sawn planks is therefore more dependent on the stand location than on the prior silvicultural treatment of the stand. 相似文献
149.
Kaolin particle films and copper-based products can be considered as possible alternatives to traditional agrochemicals used for controlling the dominant pest of olive grove areas of the Mediterranean Basin, the olive fruit fly, Bactrocera oleae (Rossi) (Dip. Tephritidae), to which this pest has already evolved resistance. Psyttalia concolor (Szèpligeti) (Hym. Braconidae) is a koinobiont larval–pupal endoparasitoid of many Tephritidae of economic importance. It has been routinely used in the Mediterranean Basin for augmentative releases against B. oleae. Detailed knowledge of lethal and sublethal effects of these agrochemicals on non target arthropods is required for effective integrated pest management programmes. The aims of this study were to evaluate direct mortality caused by kaolin and copper salts on the parasitoid and the sublethal effects on emergence of adults from treated pupae and on beneficial capacity of females through four different experiments, three at laboratory level and one in semi-field conditions. Dual choice and no-choice experiments in the case of kaolin were also performed to test kaolin oviposition repellence. The results indicated that the tested agrochemicals were not harmful to the parasitoid. No lethal toxicity or effects on beneficial capacity were recorded. The behavioural experiments, however, showed that when females could choose between parasitising through a kaolin-treated surface and a water-treated one, there was a slight reduction in the percentage of parasitised hosts for kaolin. No differences were detected when females were not given a choice. 相似文献
150.
J.M.R. Alvariño P.G. Rebollar M. Olmedo B. Alvarez-Blázquez E. Ubilla J.B. Peleteiro 《Aquaculture International》2001,9(6):477-487
The effect of 18 mg. melatonin (MLT) implants on thereproductive performance of turbot (Scophthalmus maximusL.) broodstock was determined in 20 females and 12 males. Implantedanimals showed supra-physiological plasma MLT concentrations during threemonthsafter implantation, being at that time about one hundred times higher thandiurnal MLT concentrations. Direct effects of MLT implants were observed ongonadal maturation of turbot females three months after implantation (P <0.01), although the faster ovarian response to increasing photoperiod was notconsistent and no differences were detected at the final reproductiveperformance. MLT implants had a positive effect on turbot male reproductivefeatures, since gonadal recrudescence started 45 days earlier (P < 0.05)showing a trend towards higher spermatozoa concentration. Further research isadvisable to ascertain the MLT dose required for and time of implantation inturbot broodstock. 相似文献