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131.
Antimicrobial susceptibility patterns of Haemophilus parasuis from pigs in the United Kingdom and Spain 总被引:3,自引:0,他引:3
de la Fuente AJ Tucker AW Navas J Blanco M Morris SJ Gutiérrez-Martín CB 《Veterinary microbiology》2007,120(1-2):184-191
A total of 30 British and 30 Spanish Haemophilus parasuis isolates were tested for their susceptibility to 19 of the antimicrobials currently used in swine practice with a broth microdilution method in order to know the emergence of resistance against these compounds in this porcine pathogen. All the British isolates were susceptible to penicillin, ceftiofur, erythromycin, tilmicosin, enrofloxacin, and florfenicol, and most of them were susceptible to the remaining antimicrobials (the highest resistance rate found was of 20% to neomycin). In contrast, all the Spanish isolates were susceptible exclusively to florfenicol, and high proportions of resistance were encountered for penicillin, ampicillin, oxytetracycline, erythromycin, tilmicosin, tiamulin and trimethoprim+sulphamethoxazole; in addition, a bimodal or multimodal distribution, or tailing of Spanish isolates over the MIC range was observed for clindamycin, sulphonamides and tylosine tartrate, suggesting the development of acquired resistance. In addition, several multiresistance patterns were found among the Spanish isolates, 23.3% of them being resistant to at least eight antimicrobials, the same rate as that encountered for those being susceptible to all antimicrobials tested. This study showed that in general British H. parasuis isolates are susceptible to antimicrobial agents routinely used for treatment of porcine respiratory diseases; however, the Spanish isolates need a more continuous surveillance of their susceptibility patterns. 相似文献
132.
Émilie L. Couture Beatriz P. Monteiro Jessica Aymen Eric Troncy Paulo V. Steagall 《Veterinary anaesthesia and analgesia》2017,44(3):676-683
Objectives
To validate a thermal threshold (TT) nociceptive model in bearded dragons (Pogona vitticeps) and to document TT changes after administration of morphine.Study design
A two-part randomized, blinded, controlled, experimental study.Animals
Five adult bearded dragons (242–396 g).Methods
A TT device delivered a ramped nociceptive stimulus (0.6 °C second?1) to the medial thigh until a response (leg kick/escape behavior) was observed or maximum (cut-off) temperature of 62 °C was reached. In phase I, period 1, six TT readings were determined at 20 minute intervals for evaluation of repeatability. Two of these readings were randomly assigned to be sham to assess specificity of the behavioral response. The same experiment was repeated 2 weeks later (period 2) to test reproducibility. In phase II, animals were administered either intramuscular morphine (10 mg kg?1) or saline 0.9%. TTs (maximum 68 °C) were determined before and 2, 4, 8, 12 and 24 hours after treatment administration. Data were analyzed using one-way anova (temporal changes and repeatability) and paired t tests (reproducibility and treatment comparisons) using Bonferroni correction (p < 0.05).Results
Mean TT values were 57.4 ± 3.8 °C and 57.3 ± 4.3 °C for periods 1 and 2, respectively. Data were repeatable within each period (p = 0.83 and p = 0.07, respectively). Reproducibility between periods was remarkable (p = 0.86). False-positive responses during sham testing were 10%. TTs were significantly increased after morphine administration at 2, 4 and 8 hours compared with baseline, and at 2 and 4 hours compared with saline 0.9%. The highest TT was 67.7 ± 0.7 °C at 4 hours after morphine administration.Conclusions and clinical relevance
Testing was repeatable, reproducible and well tolerated in bearded dragons. TT nociceptive testing detected morphine administration and may be suitable for studying opioid regimens in bearded dragons. 相似文献133.
Padilha ST Steagall PV Monteiro BP Kahvegian MA Ubukata R Rodrigues EO Rosa AL Aguiar AJ 《Journal of Feline Medicine and Surgery》2011,13(10):738-743
Sixteen cats were used to compare the cardiovascular and anesthetic effects of remifentanil (REMI) or alfentanil (ALF) in propofol-anesthetized cats undergoing ovariohysterectomy. After premedication with acepromazine, anesthesia was induced and maintained with a constant rate infusion of propofol (0.3 mg/kg/min). REMI or ALF infusions were administered simultaneously with propofol. Heart rate (HR), systolic arterial pressure (SAP), pulse oximetry (SpO(2)), rectal temperature (RT), and response to surgical stimulation were recorded at predefined time points during anesthesia. Data [mean±standard deviation (SD)] were analyzed by analysis of variance (ANOVA) for repeated measures followed by a Dunnett's test and Student t-test (P<0.05). SAP was significantly lower in ALF group than in REMI group. Extubation time was significantly shorter in REMI than in ALF group. Overall infusion rate of REMI and ALF was 0.24±0.05 μg/kg/min and 0.97±0.22 μg/kg/min, respectively. The combination of propofol and REMI or ALF provided satisfactory anesthesia in cats undergoing ovariohysterectomy. 相似文献
134.
Gutiérrez SE Dolcini GL Arroyo GH Rodriguez Dubra C Ferrer JF Esteban EN 《American journal of veterinary research》2001,62(10):1571-1577
OBJECTIVE: To develop a blocking ELISA for detection of bovine leukemia virus (BLV) antibodies that is comparable to a radioimmunoprecipitation (RIP) assay, to evaluate use of this ELISA for identification of BLV-infected herds, and to develop a polymerase chain reaction (PCR) assay for direct diagnosis of infection with BLV. SAMPLE POPULATION: Serum samples and pooled bulk-tank milk samples from cattle. PROCEDURE: The blocking ELISA was developed, using BLV gp51 as antigen, captured by a selected bovine polyclonal serum. A nested PCR was conducted with primers specific for a segment of the pol region of the BLV genome. RESULTS: Sensitivity and specificity of the ELISA were comparable to those of the RIP assay. Use of the ELISA on pooled milk samples allowed identification of herds in which prevalence of BLV infection among lactating cows was as low as 2.5%. Pooled milk samples from BLV-free herds did not react in the ELISA. All cattle that had positive results for the nested PCR had BLV antibodies, but cattle with consistantly low antibody titers required examination of sequential DNA samples to detect viral sequences. None of the 63 antibody-negative cattle had positive results for the PCR. CONCLUSIONS AND CLINICAL RELEVANCE: This ELISA is a highly specific and sensitive assay for the detection of BLV antibodies in serum and milk samples of cattle. Examination of pooled milk samples with the ELISA provides a reliable, practical, and economic procedure for identification of BLV-infected herds. The nested PCR also constitutes a specific procedure for direct diagnosis of infection with BLV. 相似文献
135.
A Ortega‐Pacheco M Jiménez‐Coello E Gutiérrez‐Blanco KY Acosta‐Viana E Guzmán‐Marín MA Zavala‐Sánchez NE Montalvo‐Beltrán MS Pérez‐Gutiérrez 《Reproduction in domestic animals》2010,45(6):1126-1129
Papaya seeds (Carica papaya Linn) have been found to have a significant effect on sperm characteristics in some mammals, including humans, but no studies have investigated the effects on dogs. In the present study, a significant decrease in sperm concentration was observed in a group of dogs treated with extracts from washed papaya seeds, but no decrease was observed in the group of dogs treated with non‐washed seeds. An important effect of extract components from washed seeds such as fatty acids is probably involved in the reduction of sperm production because of Sertoli cell damage, as has been suggested for langur monkeys. Dilution of the active components in the non‐washed papaya seeds or interference with some of the components may reduce the expected effect on spermatogenesis. This first report on the effects of a chloroformic extract of papaya seeds in dogs suggests that an increased dose is necessary to achieve azoospermia. 相似文献
136.
Analgesic efficacy of an oral transmucosal spray formulation of meloxicam alone or in combination with tramadol in cats with naturally occurring osteoarthritis 下载免费PDF全文
137.
Patio-Lpez Vernica Bravo-Avilez David Vargas-Mendoza Carlos F. Blancas Jos Rendn-Aguilar Beatriz 《Genetic Resources and Crop Evolution》2022,69(2):601-618
Genetic Resources and Crop Evolution - Across the process of domestication, human selection produces changes in target attributes as well as changes that are not necessarily desired by humans due... 相似文献
138.
del Río ML Gutiérrez B Gutiérrez CB Monter JL Rodríguez Ferri EF 《American journal of veterinary research》2003,64(9):1176-1180
OBJECTIVE: To determine duration and rates of recovery of Actinobacillus pleuropneumoniae and Haemophilus parasuis from 4 liquid media and 2 swab specimen transport systems and compare findings with those of Escherichia coli. SAMPLE POPULATION: One strain each of A pleuropneumoniae (biovar 1, serotype 1), H parasuis (serovar 5), and E coli (serotype O149:K91:H19). PROCEDURE: Strains were incubated in brain heart infusion broth supplemented with horse serum and other nutrients or in horse serum alone, with and without nicotinamide-adenine dinucleotide in both instances, for 150 days at 4 degrees C or room temperature (21 degrees C). Similarly, strains were tested in Stuart and Amies transport systems after storage at room temperature for 8 days. RESULTS: Colony counts greater than those of the initial inoculum were observed after incubation in horse serum for A pleuropneumoniae but not for H parasuis. Overall, incubation at 4 degrees C in the 4 liquid media resulted in longer recovery duration and higher rates than at room temperature. Culture of H parasuis resulted in lower recovery rates and shorter durations of recovery than culture of A pleuropneumoniae, except for culture in horse serum. Haemophilus parasuis survived longer than A pleuropneumoniae in the transport systems, and all organisms survived longer in the Amies system. CONCLUSIONS AND CLINICAL RELEVANCE: Survival of A pleuropneumoniae and H parasuis indicated that horse serum prolongs survivability, which may result in exposure of more animals during a prolonged period. The Amies system might be a good choice for collection of clinical samples from animals, especially for recovery of H parasuis. 相似文献
139.
Rivas Zulay de Medina Hilda Ledo Gutiérrez Janio Gutiérrer Elizabeth 《Water, air, and soil pollution》2000,117(1-4):27-37
Nitrogen (N) and phosphorus (P) concentrations were determined in sediment samples along the bed of Catatumbo river in both Colombian and Venezuelan territories until the river outlet in Maracaibo lake. Total phosphorus was determined by digestion with HCl followed by analysis using the ascorbic acid method and total nitrogen was done using the standard microkjeldahl method plus nitrate-nitrite. Ammonium, orthophosphate and nitrate were determined using standard methods after extraction steps. The mean concentrations along the river bed were found in an interval of 0.035 and 1.492 mg g-1 dry sed. for nitrogen and 0.027 and 1.039 mg g-1 dry sed. for phosphorus at 95% confidence level. The mean molar ratio N/P in the river bed was 4.42 and 3.46 for river outlet zones in the lake, which indicates that nitrogen is the limiting nutrient. For comparison with previous results of lake sediments from sites near the river outlet it was concluded that Catatumbo river is a significant source of nutrients to the Maracaibo Lake system because sediment nutrients concentrations from Catatumbo river were higher than the ones in Maracaibo Lake. Statistic studies showed significant differences between countries, zones and similar behaviour in the river bed as related to the affluent rivers. 相似文献
140.
Agustí Noya Beatriz Serrano‐Prez Daniel Villalba Isabel Casasús Ester Molina Irene Lpez‐Helguera Albina Sanz 《Animal Science Journal》2019,90(7):857-869
This experiment evaluated the effects of subnutrition during early gestation on hematology in cows (Bos Taurus) and on hematological, metabolic, endocrine, and vitality parameters in their calves. Parda de Montaña and Pirenaica dams were inseminated and assigned to either a control (CONTROL, 100% requirements) or a nutrient‐restricted group (SUBNUT, 65%) during the first third of gestation. Dam blood samples were collected on days 20 and 253 of gestation, and calf samples were obtained during the first days of life. Pirenaica dams presented higher red series parameters than Parda de Montaña dams, both in the first and the last months of gestation. During early pregnancy, granulocyte numbers and mean corpuscular hemoglobin were lower in Pirenaica‐SUBNUT than in Pirenaica‐CONTROL cows. Calves from the SUBNUT cows did not show a physiological reduction in red series values in early life, suggesting later maturation of the hematopoietic system. Poor maternal nutrition affected calf endocrine parameters. Newborns from dystocic parturitions showed lower NEFA concentrations and weaker vitality responses. In conclusion, maternal nutrition had short‐term effects on cow hematology, Pirenaica cows showing a higher susceptibility to undernutrition; and a long‐term effect on their offspring endocrinology, SUBNUT newborns showing lower levels of IGF‐1 and higher levels of cortisol. 相似文献