In vitro antimicrobial inhibition profiles of Mycoplasma bovis isolates recovered from various regions of the United States from 2002 to 2003.     

Ricardo F Rosenbusch  Joann M Kinyon  Michael Apley  Nathan D Funk  Sean Smith  Lorraine J Hoffman 《Journal of veterinary diagnostic investigation》2005,17(5):436-441

Antimicrobial therapy continues to be important in reducing losses due to pneumonic forms of Mycoplasma bovis disease in beef and dairy calves. Although M. bovis diseases have been documented as frequent and economically important in the United States, there are no published reports on the antimicrobial activity of approved compounds against US strains. In this study, the authors report on the activity of 9 different antimicrobials against 223 recently recovered isolates of M. bovis. These isolates represent accessions from 5 geographic regions of the United States and were grouped by 4 tissues of origin (milk, respiratory, joint, or ear and eye). A broth microdilution test was used to determine minimum inhibitory concentration (MIC) values by reading redox changes detected in broth with alamarBlue (resazurin) indicator. For each antimicrobial, the median, MIC50, MIC90, mode, and range were calculated, and the values used for comparisons. In the absence of accepted breakpoint values, published MIC cutoff values for animal mycoplasmas as well as Clinical Laboratory Standards Institute interpretive criteria were used as a reference to define in vitro activity. The MIC values from active antimicrobials were found to distribute independently of region of origin of the isolates or of tissue of origin. Enrofloxacin, florfenicol, and spectinomycin were found to be active compounds in vitro. Oxytetracycline and chlortetracycline were active against more than half of the isolates. Very few isolates were inhibited by tilmicosin and none by erythromycin, ampicillin, or ceftiofur. The antimicrobial profiles determined for these US strains were remarkably similar to those reported for European isolates. However, unlike in Europe, there appears to be no diversity of profiles when US isolates are grouped by region or tissue of origin.  相似文献   

Hormonally active substances in fodder plants     

E Krause 《Monatshefte für Veterin?rmedizin》1970,25(4):148-157

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Evaluation of jitter by stimulated single-fiber electromyography in normal dogs   总被引：2，自引：0，他引：2  

Añor S  Lipsitz D  Williams DC  Tripp L  Willits N  Maselli R  LeCouteur RA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(4):545-550

Single-fiber electromyography (SFEMG), a technique used to investigate neuromuscular transmission, has been described previously in the pelvic limb of dogs. Because preferential involvement of isolated muscle groups can occur in disorders of neuromuscular transmission, SFEMG was done in the peroneus longus (PL), extensor carpi radialis (ECR), and orbicularis oculi (OO) muscles of 10 adult, clinically normal dogs. Jitter was calculated as the mean absolute value of the consecutive differences in latency of 50 single muscle fiber action potentials after stimulation of intramuscular nerve bundles at the level of the motor point in at least 20 muscle fibers per muscle. Bilateral recordings were performed in 3 dogs. Mean jitter values were determined for each muscle, and differences among muscle groups and among dogs were compared. The upper limits of mean consecutive difference (mean plus 3 standard deviations) for the PL, ECR, and OO muscles were 21.94, 22.53, and 23.39 micros, respectively, and the upper limit of mean consecutive difference for individual muscle fibers in the respective fiber pools was 28.62, 36.39, and 35.68 micros. Jitter values for the ECR and OO were significantly higher than the jitter value for the PL muscle (P < .05). Significant differences among muscles or dogs or between sides were not observed for the ECR. Significant differences among dogs were observed for OO jitter values and were attributed to extremely low jitter values in 1 dog. Significant differences were demonstrated between sides for the PL and were attributed to small sample size. Results of this study provide normative data that can be used in the application of the stimulated SFEMG technique to dogs with suspected disorders of neuromuscular transmission.  相似文献   

Characterization of the immune response to Mycoplasma bovis lung infection     

Vanden Bush TJ  Rosenbusch RF 《Veterinary immunology and immunopathology》2003,94(1-2):23-33

To better understand the interaction between Mycoplasma bovis and its bovine host, we have characterized the immune response generated during an experimental lung infection with M. bovis. Proliferation ([3H]-thymidine blastogenesis) and Th1/Th2 cytokine production were used to monitor peripheral cellular immune responses. Flow cytometry analysis was used to determine T-cell subset activity by CD25 expression. Humoral immune response was monitored by the identification of antigen-specific IgG1 and IgG2 isotypes over time. Herein, we show that M. bovis antigen stimulates activation of CD4+ and CD8+ cells in vitro in a manner consistent with memory, and that gammadelta-T cells are activated by antigen in a manner consistent with innate immunity. In addition, the percentage of cells producing IFN-gamma during recall response is equal to that of IL-4 producing cells. Serological analysis shows M. bovis stimulates increased production of antigen-specific IgG1 while very little IgG2 is produced. We therefore submit that experimental lung infection of cattle with M. bovis results in a Th2-skewed immune response.  相似文献   

Flea species from dogs in three cities of Chile     

Alcaíno HA  Gorman TR  Alcaíno R 《Veterinary parasitology》2002,105(3):261-265

The purpose of this study was to establish the pattern of flea infestation in dogs in the cities of Santiago (33 degrees latitude south, 70 degrees longitude west), Concepción (36 degrees latitude south, 73 degrees longitude west) and Osorno (40 degrees latitude south, 73 degrees longitude west), located in different parts of Chile. The only species of fleas found on dogs from the three cities were Ctenocephalides felis felis (41.8%), Ctenocephalides canis (39.4%) and Pulex irritans (18.8%). Although the three species were found in the three cities, differences regarding their frequencies were detected (p<0.05). C. felis was the predominant species found on dogs in Santiago (80.5%). In Concepción, their frequencies followed a similar trend. However in Osorno, the most southern city, the predominant species was C. canis (78.7%).  相似文献   

Accuracy of serum beta-hydroxybutyrate measurements for the diagnosis of diabetic ketoacidosis in 116 dogs     

Duarte R  Simoes DM  Franchini ML  Marquezi ML  Ikesaki JH  Kogika MM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):411-417

The aim of this study was to evaluate the accuracy of serum beta-hydroxybutyrate (beta-OHB) measurements for the diagnosis of diabetic ketoacidosis (DKA) in dogs. One hundred sixteen diabetic dogs were prospectively enrolled in the study: 18 insulin-treated (IT) diabetic dogs that had a positive urine ketone test and 88 untreated, newly diagnosed diabetic dogs. Venous blood gas tensions and pH, serum glucose and urea nitrogen (SUN), and electrolyte (Na+, Cl-, and K+) and urine acetoacetate (AA) concentrations were measured concurrently with serum beta-OHB concentrations. On the basis of laboratory findings, the patients were assigned to I of 3 groups: diabetic ketoacidosis (n = 43); diabetic ketosis (DK, n = 41); and nonketotic diabetes (NDK, n = 31). Serum beta-OHB concentrations differed significantly (P < .001) among the study groups. Although marked differences in beta-OHB concentrations were found, a considerable overlap exists between the distributions of dogs with DK and those with DKA. The overall accuracy of beta-OHB determination as a diagnostic test for DKA, determined by the area under the receiver operating characteristic (ROC) curve, was 0.92. In the 1.9- to 4.8-mmol/L range, serum beta-OHB determination sensitivity varied from 100 to 35.7%, whereas specificity varied from 39 to 100%. The cutoff value of 3.8 mmol/L showed the best equilibrium between specificity (95%), sensitivity (72%), and likelihood ratio (14.8). We concluded that the quantitative measurement of serum beta-OHB may be a potential tool for diagnosing and monitoring ketosis and ketoacidosis in diabetic dogs.  相似文献   

An Evidence-Based Approach to Selected Joint Therapies in Horses     

Dean W. Richardson  Ricardo Loinaz 《Veterinary Clinics of North America: Equine Practice》2007

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Identification and localization of a 94 kDa membrane protein found in Mycoplasma bovoculi strains     

Barik A Salih  Ricardo F Rosenbusch 《Comparative immunology, microbiology and infectious diseases》1998,21(4):281-290

Six isolates of Mycoplasma bovoculi obtained from cattle herds with bovine keratoconjunctivitis were analyzed by gel electrophoresis and immunoblotting techniques. All six strains showed similarity in their protein profiles although no two patterns were identical. Antigenic differences between strains were detected in immunoblots reacted with post-exposure calf serum. A common 94 kDa protein band designated p94 was detected in all six strains reacted with monoclonal antibody MA25.5 developed to one of the strains. The p94 was also recognized in these strains by the calf serum. Trypsin treatment of intact mycoplasma cells resulted in the removal of p94 from immunoblots reacted with MA or hyperimmune rabbit serum. Other trypsin-resistant antigens shared between strains or being strain-specific in nature were identified when trypsin-treated mycoplasma cells were reacted with hyperimmune rabbit serum. The p94 antigen was shown to be of mycoplasmal origin by radio-immunoprecipitation using the MA or hyperimmune rabbit serum. These studies identify the presence of a surface antigen (p94) on M. bovoculi membrane in all strains examined that is trypsin sensitive by the use of monoclonal antibody, calf serum and hyperimmune rabbit serum.

Résumé

Six souches de Mycoplasma bovoculi, d'origine bovine (animaux affectés de keratoconjunctivite) ont été analysées par des techniques d'éléctrophorèse et par ‘immunoblotting’. Les six souches ont montré des similitudes dans leurs profils proteiniques. Cependant, aucun profil n'a été identique. Des differences antigéniques entre les souches ont étés detectées suite au traitement des immunoblots avec un sérum bovin infecté par M. bovoculi. L'anticorps monoclonal MA25.5 dirigé contre une des souches a réagi avec une bande proteinique (94 kDa) commune aux six souches. Cette bande a été designee p94. Cette bande p94 a été également identifiée chez tous les souches en utilisant le sérum bovin. Le traitement des mycoplasmes intactes par la trypsine a éliminé la bande p94 des immunoblots: cela a été démontr é par l'usage d'un anticorps monoclonal, ou par un sérum hyperimmun de lapin. D'autres antigènes résistants à la trypsine, communs ou spécifiques aux souches ont été identifiés quand les mycoplasmes traités par le trypsine ont été mélangés au sérum hyperimmun de lapin. La radioimmunoprécipitation par l'anticorps monoclonal ou le sérum hyperimmun de lapin a demontré que l'antigène p94 est d'origine mycoplasmique. Ces études identifient la présence d'un antigène de surface (le p94) localisé sur la membranc de M. bovoculi chez toutes les souches examinées. Cet antigène est sensible à la trypsine. Cela a été montré avec l'anticorps monoclonal, le sérum bovin et le sérum hyperimmune du lapin.  相似文献   

Cloning and expression in Escherichia coli of Mycoplasma gallisepticum antigens recognized by sera from infected chickens     

D C Krause  S H Kleven  K K Lee 《Avian diseases》1990,34(2):466-472

A clone bank of Mycoplasma gallisepticum (MG) strain A5969 DNA was prepared in the expression vector phage lambda gt11. Approximately 75% of the resulting phages were recombinants, based upon the insertional inactivation of the lacZ gene of the vector. Clones were screened immunologically with serum prepared from specific-pathogen-free white leghorn chickens that had been infected with aerosolized MG. Approximately 250 clones, or less than 1% of the recombinant phage, reacted positively to various degrees with the test serum and failed to react with serum from uninfected specific-pathogen-free control chickens. A single clone was chosen at random for comparison with a vector control by western immunoblot, revealing a polypeptide of 140,000 molecular weight in the clone profile but not the control profile that reacted with immune serum. Clones expressing MG antigens recognized during infection may provide an improved means for antigen preparation for serologic diagnosis of mycoplasmosis.  相似文献   

Birds as predators of cork and holm oak pests     

Ricardo S. Ceia  Jaime A. Ramos 《Agroforestry Systems》2016,90(1):159-176

The recent decline of Mediterranean oak woodlands in SW Iberian Peninsula is related to insect pests which affect both cork oak (Quercus suber) and holm oak (Quercus rotundifolia). We identified twenty-six bird species as potential regular predators of twenty major pests by reviewing the diet of breeding, wintering and resident species in this ecosystem. Foraging guilds are strongly associated with predation at distinct stages of the pests’ life-cycle: ground-foragers prey on overwintering pupae and larvae of seed-borers, tree-foragers prey on eggs, larvae and pupae of defoliating and wood-boring pests, and aerial-sweepers prey on airborne imagines. Bird predation can cover the complete life-cycle of pest species because different species may be complementary due to a dissimilar exploitation of foraging niches and periods. Small generalist tree-foraging passerines are important pest predators given their high densities and widespread distribution in Mediterranean oak woodlands, but management practices can have a significant negative effect in their populations.  相似文献