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81.
A proposal of clinical breakpoints for amoxicillin applicable to porcine respiratory tract pathogens
Schwarz S Böttner A Goossens L Goosens L Hafez HM Hartmann K Kaske M Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Luhofer G Richter A Schulz B Sigge C Waldmann KH Wallmann J Werckenthin C 《Veterinary microbiology》2008,126(1-3):178-188
In the present position paper, an attempt was made to establish clinical breakpoints of amoxicillin to classify porcine respiratory tract pathogens as susceptible, intermediate or resistant based on their minimum inhibitory concentrations of amoxicillin. For this, a thorough review of the published literature with regard to swine-specific pharmacological data (including dosages of amoxicillin applied and routes of administration used), clinical efficacy, and in vitro susceptibility of the target pathogens was performed. Based on the comparative analysis of the results, the working group "Antibiotic Resistance" of the German Veterinary Medical Society (DVG) proposed to classify porcine respiratory tract pathogens that show MIC values of amoxicillin of < or =0.5microg/ml as "susceptible", those with MICs of 1microg/ml as "intermediate", and those with MICs of > or =2microg/ml as "resistant". 相似文献
82.
Romero B Aranaz A Sandoval A Alvarez J de Juan L Bezos J Sánchez C Galka M Fernández P Mateos A Domínguez L 《Veterinary microbiology》2008,132(1-2):87-95
The role of wildlife in tuberculosis epidemiology is being widely studied since it can affect the effectiveness of eradication campaigns in cattle. The health problem is enhanced when it concerns also wildlife welfare and biodiversity conservation. This study was performed to understand the epidemiology of Mycobacterium bovis population affecting livestock and wild animals in the Do?ana National Park using bacteriology and molecular characterisation techniques. Tuberculosis research was performed on 1209 cattle and wild animals (artiodactyla and carnivore) collected over 6 years in the Park. One hundred and sixty-three animals were found to be infected with M. bovis, comprising 7.96% of the cattle and 20.53% of the wild animals tested. Spoligotyping revealed nine patterns, being SB1232 and SB1230 the most prevalent (77.30% and 15.34% of infected animals, respectively). MIRU-VNTR analysis of a selected panel of 92 isolates showed eight different profiles, including several spoligotypes within the same MIRU-VNTR profile. The discriminatory capacity of both techniques in this panel was similar. The results obtained by combination of both techniques corroborate that wildlife species are infected with the M. bovis strains which are more prevalent in cattle and reveal their persistence. Genotype variation between isolates strongly suggests micro-evolutionary events in the M. bovis population in the same area. This study in the Do?ana National Park exposes the risk of introduction of domestic animals into wildlife areas when there is not a warranty of disease freedom, appropriate diagnostic techniques and control measures. 相似文献
83.
Mycoplasma mycoides subsp. mycoides SC (MmmSC) is the etiological agent of contagious bovine pleuropneumonia (CBPP). Although eradicated in most developed countries, the disease reappeared in Europe in the 1990s. This reappearance may have been caused either by importation from sub-Saharan Africa, where CBPP is still endemic, or by the reemergence of virulent strains in Europe, as suggested by earlier studies. A multilocus sequence analysis scheme has been developed to address this issue and, most importantly, to be able to monitor new epidemics. The alignment of the full genome sequence of the reference strain PG1 and the partial genome sequence of a pathogenic strain allowed the identification of polymorphic sites. Nineteen initial loci were selected within housekeeping genes, genes of unknown function and non coding sequences. The suitability of these loci for genotyping MmmSC strains was first tested on six strains of diverse geographic origin. The analyses showed that the published PG1 sequence contained a number of specific polymorphisms that were therefore of no use for molecular typing. Among the eight informative polymorphic loci finally selected, only one (ftsY) was positioned within a housekeeping gene. Three main groups and 31 different allelic profiles were identified among 51 strains and strain variants examined. Cluster analysis confirmed that European strains from the 1990s did not originate from Africa. It also showed a genetic link between a European strain isolated in 1967 and those found in southern Africa and Australia. This was in agreement with historical data showing that CBPP was introduced in these regions during colonisation in the 19th century. 相似文献
84.
Abi-Ghanem D Waghela SD Caldwell DJ Danforth HD Berghman LR 《Veterinary immunology and immunopathology》2008,121(1-2):58-67
A single-chain antibody library against Eimeria tenella sporozoites was constructed by phage display. Antibody-displaying phage was selected in five panning rounds against cryopreserved E. tenella sporozoites. A 1000-fold increase in phage output and a 3000-fold enrichment were obtained after three rounds of panning, as the binding clones became the dominant population in the library. Ten clones were randomly selected from the last selection round, and their nucleotide sequences were aligned and compared to chicken germ-line sequences. Analysis of the light chain variable regions revealed possible donor pseudogenes which act as donors in gene conversion events, and contribute to the diversification of the V(L) immune repertoire. Possible somatic hypermutation events, a consequence of affinity maturation, were also identified. Soluble antibody was produced in a non-suppressor E. coli strain, purified by nickel affinity chromatography, and characterized by immunoblotting. In an immunofluorescence assay, this recombinant antibody showed specific binding to E. tenella sporozoites. 相似文献
85.
Oanh Nguyen Cong Taminiau Bernard Dang Pham Kim Luc Do Duc Moula Nassim Huyen Nguyen Thi Thinh Nguyen Hoang Daube Georges Bindelle Jrme Ton Vu Dinh Jean‐Luc Hornick 《Animal Science Journal》2019,90(8):948-960
The aim of this study was to evaluate the effects of diets containing rice distillers’ by‐product (RDP) on growth performance, carcass characteristics, meat quality, and gut microbiota of fattening pigs. Twenty‐four crossbred finishing pigs (Duroc × Landrace × Yorkshire), 56.9 ± 3.1 kg initial body weight, were randomly allocated to three groups. For 56 days, pigs were fed one of three diets including RDP0 (control), RDP15 (15% RDP in DM), and RDP30 (30% RDP in DM). With RDP level in diet, average daily gain and backfat thickness linearly increased (p < 0.05), and drip loss tended to increase (p ≤ 0.08). In addition, 16S ribosomal RNA gene amplicon profiling showed that RDP was associated with modulation of colonic microbiota composition, especially at family and genus levels. Relative abundance of Porphyromonadaceae and Erysipelotrichaceae families in colonic digesta increased with inclusion of RDP, while that of Enterobacteriaceae decreased. The proportion of genera unclassified Erysipelotrichaceae, and Butyrivibrio increased as inclusion of RDP. These results indicate that up to 30% inclusion in diet of finishing pigs, RDP can modulate colonic microbiota composition, and induces an improvement of animal growth and fat deposition. 相似文献
86.
87.
88.
The objective of this study is to investigate the effect of contrasting spring grazing dates (GD) and stocking rate (SR) on sward characteristics, grass dry matter intake and milk production performance of autumn calving dairy cows during the spring period. Two swards were created by grazing in March (early grazing; E) or by delaying first grazing until mid-April (late grazing; L). Two stocking rates, high (H; 5.5) and medium (M; 4.5) were applied across each sward. Forty eight autumn calving Holstein cows (160 ± 35 days in milk) were assigned to one of four (n = 12) different grazing treatments. The experiment began on April 17th and finished after 2 grazing rotations on June 20th. Later spring grazing significantly increased herbage mass (kg DM/ha) above ground level (+ 933, P < 0.05) and > 50 mm (+ 738, P < 0.05). Compressed sward height (+ 22.1 mm, P < 0.05), extended tiller height (+ 73 mm, P < 0.001) and pseudostem height (+ 35 mm, P < 0.001) were also significantly higher for later grazed swards. In the grazing horizon (> 80 mm— extended tiller height), later grazed swards had significantly lower leaf proportion (− 0.09, P < 0.05) and higher dead material (+ 0.05, P < 0.001). Daily herbage allowance (> 50 mm) was on average 12.7, 15.9, 18.2 and 21.9 kg DM/cow for EH, EM, LH and LM, respectively. Daily leaf allowance (> 80 mm) was 10.1, 12.3, 13.3 and 14.5 kg DM/cow for EH, EM, LH and LM, respectively. The EM (16.2 kg DM/cow), LH (+ 0.1 kg) and LM (0.8 kg) treatments all had similar grass DM intake, however there was evidence of an interaction (P < 0.10) between GD and SR, this was due to the low grass DM intake of the EH (13.9 kg DM/cow) treatment. When expressed as UFL (Fill unit) intake the EM treatment recorded the highest value. There was a significant interaction between GD and SR (P < 0.01) for milk, protein yield, 4% fat corrected milk yield (P < 0.05) and protein concentration (P < 0.001). Cows grazing the EM treatment produced 23.9 kg of milk, 876 and 685 g of fat and protein yield. The difference in milk production (cow/day) between EM and EH treatments was + 3.6 kg milk, + 98 g fat and + 107 g protein. The production yield difference between LM and LH treatments was + 1.1 kg milk, + 27 g fat and + 29 g protein in favour of the LM treatment (23.9 kg of milk, 877 and 687 g fat and protein yield). Herbage quality and morphological characteristics are clearly improved with early spring grazing as herbage mass is reduced on subsequent rotations. Swards grazed in early spring allow higher grass utilisation and high milk production performance when grazed at a medium stocking rate. Improved milk production from herbage can be achieved provided herbage mass and allowance are maintained at levels where herbage quality decreases are minimised. 相似文献
89.
Stijn Schauvliege Anna Binetti Luc Duchateau Jacoba Johanna van Dijk Frank Gasthuys 《Veterinary anaesthesia and analgesia》2018,45(5):648-657
Objective
To evaluate the cardiorespiratory effects of a 7° reverse Trendelenburg position (RTP) in anaesthetized horses.Study design
Randomized, non-blinded clinical trial.Animals
A total of 125 horses undergoing elective surgery in dorsal recumbency.Methods
Horses were allocated to one of three weight classes and assigned to be positioned either on a horizontal table or on a table in 7° RTP, according to a randomized block design. In all horses, anaesthesia was maintained with isoflurane in oxygen and a constant rate infusion of romifidine. All horses were mechanically ventilated throughout anaesthesia, and routine cardiovascular monitoring and arterial blood gas analysis were performed at 15-minute intervals and relevant variables calculated. Data from the first 60 minutes of anaesthesia were compared between both positions using a mixed model analysis of variance.Results
A significant interaction was found between position and weight class for the alveolar to arterial oxygen tension gradient and F-shunt: these variables were lower in RTP than in horizontal position in the two lowest weight classes and vice versa in the highest weight class. Arterial oxygen tension and oxygenation indices were significantly worse in the horses in the higher weight classes.Conclusions and clinical relevance
A 7° RTP did not result in clinically relevant changes in gas exchange or cardiovascular function. Horses with a higher body weight are at increased risk for hypoxaemia during anaesthesia in dorsal recumbency. 相似文献90.
Gibson TJ Johnson CB Stafford KJ Mitchinson SL Mellor DJ 《New Zealand veterinary journal》2007,55(4):152-157
AIM: To validate use of the electroencephalogram (EEG) and a minimal anaesthesia model for assessment of noxious sensory input caused by scoop dehorning of calves. METHODS: Twenty Friesian heifers weighing 125-178 kg were maintained under light general anaesthesia using halothane and an established protocol (minimal anaesthesia model). They were then dehorned using a scoop dehorner either with (DH+LA) or without (DH) a lignocaine ring block, and changes in the EEG and electrocardiogram (ECG) recorded. Median frequency (F50), 95% spectral edge frequency (F95) and total power (Ptot) were derived from the EEG data. RESULTS: There were significant increases in the F50 (p<0.01) and F95 (p<0.01), and a decrease in Ptot (p<0.01) following dehorning in the DH group, but there were no changes in the DH+LA group. Transient bradycardia in the first 75 sec following dehorning was recorded in the DH group compared with both pre-treatment values in the same group and with the DH+LA group (p<0.001). Tachycardia was evident by 15 min after dehorning in the DH but not the DH+LA group. CONCLUSIONS: The results validate use of the EEG and a minimal anaesthesia model for assessment of noxious sensory inputs in cattle. 相似文献