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41.
Numerous methods are currently used throughout the poultry industry for the administration of vaccines. Each utilizes water for vaccine reconstitution and/or administration, including two of the three commercially available live Mycoplasma gallisepticum (MG) vaccines. Selected water temperatures were used to reconstitute and/or dilute the three commercially available live MG vaccines. Water temperatures included 4 C, 22 C (room temperature), and 32 C, and titer (color change units) was recorded at four time intervals, at point of reconstitution (time 0), 15, 30, and 60 min postreconstitution of the vaccines (time periods 15, 30, and 60, respectively). Results for F strain MG (FMG) vaccine showed significant decreases in titer from time 0 to time 15 for the 22 C and 32 C water temperatures but no significant decrease for any time period for FMG reconstituted with 4 C water. For 6/85 strain MG no significant difference in titer was noted for any of four time periods within any of the three water temperatures. For ts-11 strain MG a significant decrease was observed in titer at each of the four postdilution time periods when diluted with 32 C water. There was no significant decrease in titer at any time period for ts-11 MG vaccine when diluted with either 4 C or 22 C water.  相似文献   
42.
Peripheral vein phlebitis (inflammation) is a relatively frequent complication in dogs, however, published information on the ultrasonographic characteristics is currently lacking. This prospective, observational study describes the ultrasound (US) characteristics of normal canine cephalic veins, and veins with clinical phlebitis. Correlations among US findings and between US findings versus time that the intravenous catheter was in place were investigated. Safety of the US procedure was evaluated. Fifty patients were prospectively recruited for the study and 18 met the final inclusion criteria. Each patient underwent daily US examinations and was assessed for multiple criteria (vascular wall appearance, compressibility, spontaneity of flow, color fill, and presence/absence of filling defects, flow contour, direction, non‐pulsatility). Characteristics of normal canine cephalic veins were as follows: smooth and thin wall, complete compressibility, no flow disturbances, no filling defects, smooth flow contours, and unidirectional, non‐pulsatile flow with no turbulence. Characteristics of cephalic veins with clinical phlebitis were as follows: wall thickening (83%), decreased compressibility (55%), filling defects consistent with intraluminal thrombus (55%), vessel wall hyperechogenicity (44%), and abnormal color Doppler flow (39%). Significant correlations were found between Doppler filling defects and compressibility, Doppler filling defects and presumed thrombosis, and compressibility and presumed thrombosis (P = .001, P = .001, P = .000, respectively). No correlation was found between the US findings and time the intravenous catheter was in place. Findings indicated that duplex and compressibility US are feasible and safe methods for characterizing and monitoring cephalic veins in dogs with clinical phlebitis.  相似文献   
43.
Multilocus-sequence typing (MLST) was used to analyse Streptococcus uberis isolates from a single herd associated with long duration (50-260 days) and rapidly cleared (less than 1 month) bovine intramammary infections to determine whether the bacterial type had any impact on the duration of infection. Most chronic infections (24 of 33) were due to continuous infection of the mammary quarter with the same sequence type, and infections were found to persist for many months. The remaining quarters were re-infected with a different sequence type within a single lactation. No particular sequence type or clonal complex (lineage) was associated with persisting infections, indicating that the outcome of intramammary infections with S. uberis is more likely to be dependent on host factors than on inter-strain differences. Analysis of these strains alongside others obtained from the same herd at a later date revealed the shift in the predominant genotypes with time.  相似文献   
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45.
The development of biofloc production technology has generated significant commercial and research interest directed toward the inland culture of Pacific white shrimp, Litopenaeus vannamei. Most work to date has been conducted in greenhouses, where photoautotrophic organisms are significant contributors to system functionality. In more temperate locations, operations in insulated buildings would reduce heating costs. This experiment was designed to evaluate the effect of light on shrimp cultured in intensive biofloc systems. A 92‐d experiment was conducted in 3.8‐m3 tanks. There were five light treatments: (1) natural sunlight (SUN) as a control (midday: 718 lx); (2) one metal halide light (MHL) (1074 lx); (3) one fluorescent light (1FL) (214 lx); (4) two fluorescent lights (2FL) (428 lx); and (5) three fluorescent lights (3FL) (642 lx). Artificial light treatments operated on a 12:12 daily cycle. There were three replicate tanks per treatment and each was separated by black plastic to prevent light transmission between replicates. Each tank was stocked at 465 shrimp/m2 of tank bottom (initial mean weight = 0.4 g). Light treatment had a significant (P≤ 0.05) impact on average individual weight, survival, harvest yield (kg/m2), and feed conversion ratio (FCR). Harvest yield and survival among shrimp in the SUN, MHL, and 1FL treatments were not significantly different. However, there was an inverse linear relationship (P≤ 0.05; R2 = 0.76) between the number of fluorescent fixtures and survival, which was related to greater concentrations of filamentous bacteria as the intensity of fluorescent light increased, causing gill fouling. Natural light and MHL did not result in high concentrations of filamentous bacteria. These results indicate that natural light, metal halide lighting, and/or relatively low levels of fluorescent lighting are suitable for indoor production of Pacific white shrimp in biofloc systems. Light spectrum and intensity can affect bacterial community structure, which has a profound effect on shrimp survival and production.  相似文献   
46.
The Eurasian badger (Meles meles) is a wildlife reservoir for Mycobacterium bovis infection in Ireland and Great Britain and has been implicated in the transmission of tuberculosis to cattle. Vaccination of badgers is an option that could be used as part of a strategy to control the disease. In this study we used an endobronchial infection procedure to inoculate groups of badgers with three different doses (3x10(3), 2x10(2) and <10 Colony Forming Units (CFUs)) of M. bovis. After 17 weeks the disease status of each animal was determined by post-mortem pathology and culture for M. bovis. Each of the inoculum doses resulted in establishment of infection in the badgers. The cell-mediated immune (CMI) responses were measured by lymphocyte transformation assay (LTA) of peripheral blood mononuclear cells (PBMCs) cultured with bovine tuberculin (PPD-B). In each infected group the CMI responses increased with a kinetic profile corresponding to the delivered dose and the post-mortem pathology. The serological responses were measured by ELISA and a multi-antigen print immunoassay (MAPIA) in order to investigate any changes in the antigenic repertoire associated with different infective doses. In contrast to the CMI responses, the ELISA and MAPIA showed that the recognition of antigens by the badgers was intermittent and not strongly influenced by the dose of M. bovis.  相似文献   
47.
Background: Bronchoalveolar lavage (BAL) fluid is evaluated for the diagnosis and study of lung disease and airway inflammation. Cytologic profiles for BAL fluid have not been reported for badgers and may be useful in understanding the pathogenesis of pulmonary diseases such as Mycobacterium bovis. Objective: The aim of this study was to evaluate cytologic and microbial findings in BAL fluid from captive European badgers (Meles meles) and identify correlates with the results of concurrently collected blood and fecal samples. Methods: BAL fluid (by a nonbronchoscopic method) and jugular venous blood samples (for routine CBC) were obtained from 23 captive tuberculosis‐free anesthetized badgers on 2 occasions 4 weeks apart. Fecal samples were collected for routine parasitology. Morphologic evaluation and 100‐cell differentials were done on cytocentrifuged BAL specimens. Pellets from centrifuged BAL were aerobically cultured for bacteria. Results: With the 2 BAL samples from each of the 23 badgers combined, the median (range) cell percentages were 73.0% (5–95%) neutrophils, 7.5% (2–16%) macrophages, 8.0% (0–27%) lymphocytes, and 9.5% (0–92%) eosinophils. Macrophages frequently contained silica‐like crystals. Other findings included ciliated epithelial cells, goblet cells, mucus, and Aelurostrongylus sp. larvae. A light growth of Streptococcus, Pasteurella, or Escherichia coli was cultured in 6 badgers. Trypanosoma pestanai were identified in blood from 10 badgers and fecal parasites (mainly coccidia) were found in 20 badgers. No correlation was found between BAL and CBC results and the presence of parasites. Conclusions: The predominance of neutrophils in BAL fluid from badgers differs from the predominance of macrophages found in BAL from other species. This difference may reflect the burrowing lifestyle or the unique immune response of badgers.  相似文献   
48.
ABSTRACT

Pathogenic microorganisms may be incorporated into biofilms found in aquaculture systems, causing recurring exposure to potential disease agents. Aerobic plate counts, the presence of Enterobacteriaceae, and the presence of Escherichia coli, modified to express a green fluorescent protein (GFP E. coli), was used to evaluate the effectiveness of various sanitizers in decreasing bacterial incorporation into newly generated biofilms in recirculating aquaculture systems. Disks of Buna-N rubber, polyvinyl chloride (PVC), chlorinated PVC, glass, fiberglass, and stainless steel were placed in aquariums stocked with Nile tilapia, Oreochromis niloticus. The effectiveness of water, an alkaline cleanser, sodium hypochlorite, a quaternary ammonium compound, or peracetic acid as a sanitizer was evaluated on each substrate by enumerating total plate counts, GFP E. coli, and Enterobacteriaceae. Sodium hypochlorite and peracetic acid were the most effective sanitizers, with an overall percentage reduction of GFP E. coli of approximately 2 logs10. The quaternary ammonium compound was moderately effective, 1 log10, against the target organisms. Water demonstrated a 2 log10 reduction of the total plate count, suggesting that some mechanical cleaning was achieved. The type of material used as substrate for the biofilm had no significant (P?>?0.05) effect on the effectiveness of the sanitizers.  相似文献   
49.
50.
Production losses from abortions, stillbirths, and early calf mortality were described for the 2002 calf crop in 203 beef herds in western Canada. A total of 1689 calves were examined. A summary diagnosis was reported for 64% of aborted calves, 78% of stillborn calves, 88% of neonatal calves, and 94% of the calves > 3 d of age. Diagnoses for aborted calves included: thyroid gland lesions, pneumonia, developmental anomalies, placentitis, and myocardial necrosis or myopathy. For stillborn calves, diagnostic findings included: dystocia, thyroid gland lesions, myocardial necrosis or myopathy, developmental anomalies, and skeletal myopathy or necrosis. The most common diagnoses for neonatal calves (≤ 3 d) were: pneumonia, skeletal myopathy or necrosis, myocardial necrosis or myopathy, accident or trauma, and septicemia. For older calves (3 d to 3 mo), the most common diagnoses included: starvation, abomasal ulcer or perforation, enteritis or colitis, pneumonia, and intestinal volvulus, obstruction, or perforation.  相似文献   
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