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941.
    
One hundred and seven fattening pig units randomly selected in Catalonia (Spain) were surveyed during 2001-2003, in order to determine the frequency of the prophylactic use of antimicrobials and mass treatments against respiratory and enteric disease outbreaks. Logistic regression and regression tree analysis were done to determine the factors associated with the on-farm mass antimicrobial usage. Fifty-eight per cent of the surveyed farms used mass antimicrobial prophylaxis; among them, 39% used two or more antimicrobials. The more frequently administered drugs were colistin, beta-lactams and tetracyclines. Fattening units from strict finishing farms were more likely to use antimicrobials than farrow-to-finish farms (Odds Ratio = 11.7) and farms with changing facilities were less likely to use these compounds (OR = 0.17). In the event of a respiratory disease outbreak, most farms applied mass treatment and 46% used two or more compounds, with tetracyclines, beta-lactams and sulphonamides being the most popular ones. Mass treatment with several compounds in case of respiratory problems was significantly related to the use of growth promoters on the farm (OR = 4.3). If an outbreak of an enteric disease occurred, most farms resorted also to a mass treatment and 48% used two or more drugs. The most frequent antimicrobial agent for the treatment of enteric disease was colistin. Fattening farms (OR = 6.9) and operations that perform routine antimicrobial prophylaxis (OR = 2.0) were more likely to use more than one antimicrobial agent for enteric diseases.  相似文献   
942.
943.
OBJECTIVE: To determine the susceptibility of strains of Pasteurella multocida subsp multocida isolated from lung specimens of pigs with pneumonia to 20 antimicrobials and to evaluate the emergence of resistance to those antimicrobials in Spain during the past 2 decades. SAMPLE POPULATION: 63 isolates recovered from 1987 to 1988 and 132 isolates recovered from 2003 to 2004. PROCEDURE: A broth microdilution method was used to determine minimal inhibitory concentration (MIC) range and values for MIC50 and MIC90. Resistance of a strain to an antimicrobial agent was determined by use of the breakpoint value when available. RESULTS: Isolates were generally susceptible to penicillin, ampicillin, ceftiofur, gentamicin, apramycin, neomycin, spectinomycin, chlortetracycline, erythromycin, tilmicosin, enrofloxacin, and florfenicol, and most isolates were resistant to clindamycin, tylosin tartrate, and tiamulin regardless of the time period. A substantial increase in resistance to sulfa-chlorpiridazine, sulfadimethoxine, sulfathiazole, and trimethoprim-sulfamethoxazole was observed, and a minor increase in resistance to oxytetracycline was also detected. Several multiresistance patterns were observed, most frequently among isolates recovered in the 2003 to 2004 interval. CONCLUSIONS AND CLINICAL RELEVANCE: Ceftiofur, florfenicol, and enrofloxacin are recommended for treatment of infections caused by P multocida subsp multocida in Spain. Increased frequency of resistance to oxytetracycline and sulfonamide drugs may be a contraindication for their use.  相似文献   
944.
OBJECTIVE: To evaluate bispectral index (BIS), spectral edge frequency 95% (SEF), and median frequency (MED) in relation to a visual analogue scale (VAS) as indicators of anesthetic depth for various concentrations of sevoflurane and isoflurane in pigs. ANIMALS: 32 pigs. PROCEDURE: Pigs were randomly allocated to 8 groups (4 pigs/group). An electroencephalogram (EEG) was recorded in each conscious pig. Pigs were then anesthetized by use of sevoflurane (n = 16) or isoflurane (16). Agents were administered in oxygen at minimum alveolar concentrations (MACs) of 1, 1.25, 1.5, and 1.75 MAC in a randomized order. End-tidal sevoflurane and isoflurane concentrations were maintained for 30 minutes, after which an EEG was recorded for 5 minutes; BIS, SEF, and MED were then calculated. Anesthetic depth was evaluated by use of the VAS. Cardiovascular and EEG responses to nociceptive stimuli were evaluated for each anesthetic agent. RESULTS: BIS decreased significantly for the various concentrations of each anesthetic. At equivalent MACs, BIS values were significantly higher during sevoflurane-induced anesthesia than during isoflurane-induced anesthesia. Values of MED and SEF decreased significantly from basal values to 1 MAC of sevoflurane and isoflurane. For both agents, there was good correlation between VAS scores and BIS values and between VAS scores and SEF values. CONCLUSIONS AND CLINICAL RELEVANCE: BIS was useful for predicting changes in anesthetic depth at clinical dosages of inhalant anesthetics. Values of BIS, SEF, and MED were significantly higher during anesthesia induced by administration of sevoflurane than during anesthesia induced by administration of isoflurance at equivalent MACs.  相似文献   
945.
  总被引:1,自引:0,他引:1  
We evaluated the effects of 3 additives, sodium butyrate (AC), avilamycin (AB), and a combination of plant extracts (XT), on the productive performance and the intestinal environment of the early-weaned pig. The XT was a standardized mixture with 5% (wt/wt) carvacrol (from Origanum spp.), 3% cinnamaldehyde (from Cinnamonum spp.), and 2% capsicum oleoresin (from Capsicum annum). Pigs (n = 32) weaned at 18 to 22 d of age with an initial BW of 6.0 +/- 0.10 kg were allocated to 8 pens that, in turn, were allocated to 4 treatments. The treatments included a basal diet (CT) or the basal diet supplemented with 0.3% of AC, 0.04% of AB, or 0.03% of XT. Productive performance was determined during the initial 14 d postweaning. On d 19 and 21 of the experiment, the pigs were killed to allow collection of digesta and intestinal tissue to evaluate variables indicative of aspects of the gastrointestinal environment. Treatments AB and AC improved G:F (P = 0.012 and 0.003, respectively) compared with the CT. Butyrate included in the diet was only detected in the stomach but not in cranial jejunum. When compared with CT, AC produced a lower ileal starch digestibility (P = 0.002) and a lower whole-tract OM and starch digestibility (P = 0.001 and 0.003, respectively), related to a lower VFA concentration in the cranial colon (P = 0.082) and a numerically reduced branched VFA percentage in the rectum. The AB treatment diminished propionate production in caudal colon (P = 0.002) and rectum (P = 0.012) compared with CT. The AC group exhibited deeper crypt depth in the jejunum without variations in villus height compared with CT (P = 0.042). The AC and AB groups also increased goblet cell presence in the colon (P = 0.001 and 0.032, respectively). On the other hand, AB and XT diminished intraepithelial lymphocytes in the jejunum (P = 0.003 and 0.034, respectively). The XT increased lymphocyte presence in the colon (P = 0.003). These results show the important influence of AB and AC on productive performance and on pig gut dynamics. The intestinal modifications observed for AB and AC compared with CT suggest distinct modes of action for each additive.  相似文献   
946.
947.
The purpose of this study was to investigate the relationship between the existence of lung lesions in pigs at slaughter and the concentration of the serum acute phase proteins (APP), haptoglobin (Hp), pig-major acute protein (Pig-MAP) and C-reactive protein (CRP). A total of 24 pig farms were selected out of a larger farm database previously screened to study risk factors associated with pleuritis and cranio-ventral pulmonary consolidation (CVPC) lesions at slaughter-aged pigs in Spain. The farms were classified as “pleuritis negative (P−) or positive (P+)” and as “CVPC negative (M−) or positive (M+)” and divided into four groups according to a 2X2 factorial design (P−M−, P−M+, P+M−, P+M+). Also at slaughter, blood from 20 randomly selected pigs from each farm was collected. Obtained serum samples were used to measure acute phase proteins. All APP concentrations were significantly higher for M+ farms than for M− ones. However, only Hp and Pig-MAP showed significantly higher concentrations for P+ farms than for P− ones. Pig-MAP was the most sensitive biomarker since it was able to clearly discriminate between P−/P+ and M−/M+ groups (p < 0.001 in both cases). Hp was an excellent marker for pleuritis and good for CVPC lesions. CRP was able to discriminate for CVPC lesions but not for pleuritis. The present results indicate that Pig-MAP and, possibly Hp, may be used as potential markers to characterise and discriminate respiratory lesions in swine herds at slaughter.  相似文献   
948.
Horses (n=35) underwent orchidectomy in a single institution with a re-sterilised LSA as sole means of haemostasis. During the surgery, the gross quality of the seal, the stickiness of the forceps to the tissues, bleeding/oozing from the stump and the need for a subsequent application in already severed spermatic cord were assessed for haemostasis quality. After surgery, physical parameters (appearance of the mucous membranes, quality of the peripheral pulse, heart rate, respiratory rate, rectal temperature and blood dripping from the incisions), haematology or packed cell volume and total protein were monitored to assess signs of bleeding or any other condition. For cleanliness and asepsis assessment, signs of surgical infection were recorded. Complications during surgery were mild degree of sticking of the LSA forceps to the tissues and dulling of the blade. There was no need to reapply LSA a second time except in one horse. This means a haemostasis complication rate of 2.85 per cent of the horses. No postoperative bleeding was detected. Only two horses with fever had associated signs of surgical site infection. This means an infection rate of 5.71 per cent of the horses.  相似文献   
949.
Tropical Animal Health and Production - Shiga toxin–producing Escherichia coli (STEC) is an important public health concern pathogen, as it produces two toxins, Stx1 and Stx2, with cytotoxic...  相似文献   
950.
Grasslands are one of the most modified biomes on Earth. Land use changes had a large impact on carbon (C) stocks of grasslands. Understanding the impact of land use/land cover changes on C stocks and fluxes is critical to evaluate the potential of rangeland ecosystem as C sinks. In this article we analyze C stocks and fluxes across the environmental gradients of one of the most extensive temperate rangeland areas: the Río de la Plata Grasslands (RPG) in South America. The analysis summarizes information provided by field studies, remote sensing estimates, and modeling exercises. Average estimates of aboveground net primary production (ANPP) ranged from 240 to 316 g C· m?2·yr?1. Estimates of belowground NPP (BNPP) were more variable than ANPP and ranged from 264 to 568 g C· m?2·yr?1. Total Carbon ranged from 5 004 to 15 008 g C· m?2. Plant biomass contribution to Total Carbon averaged 13% and varied from 9.5% to 27% among sites. The largest plant C stock corresponded to belowground biomass. Aboveground green biomass represented less than 7% of the plant C. Soil organic carbon (SOC) was concentrated in the slow and passive compartments of the organic matter. Active soil pool represented only 6.7% of the SOC. The understanding of C dynamics and stocks in the RPG grasslands is still partial and incomplete. Field estimates of ANPP and BNPP are scarce, and they are not based on a common measurement protocol. Remotely sensed techniques have the potential to generate a coherent and spatially explicit database on ANPP. However, more work is needed to improve estimates of the spatial and temporal variability of radiation use efficiency. The absence of a flux tower network restricts the ability to track seasonal changes in C uptake and to understand fine-scale controls of C dynamics.  相似文献   
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