Identification and antimicrobial susceptibility of bacteria and yeasts isolated from healthy dogs and dogs with otitis externa.

The bacterial and fungal flora of the external ear canal of dogs with otitis externa and of healthy dogs were studied. The most frequently isolated microorganism from otitic ears was Staphylococcus intermedius (58.8%), followed by Malassezia pachydermatis (30.9%), Streptococcus canis (29.9%), Proteus spp. (14.4%) and Escherichia coli (10.3%). A statistical analysis of our results showed that the prevalence of these microorganisms is significant in dogs with otitis externa. Furthermore, the antimicrobial susceptibility patterns of isolated strains were determined. Majority of all bacterial isolates were most susceptible to gentamicin. Malassezia pachydermatis, the most prevalent yeast in this study, showed an excellent level of susceptibility to all antifungal agents tested.

[Growth and detection of aerobic bacterial pathogens in BacT/Alert FA, BacT/Alert SA, Bactec Plus Aerobic/F and Bactec Standard Aerobic/F]. / Rust a detekce aerobních bakteriálních patogenu v lahvickách BacT/Alert FA, BacT/Alert SA, Bactec Plus Aerobic/F a Bactec Standard Aerobic/F.

The article compares the ability of detection and detection times (TTD) of aerobic bacteria in the BacT/Alert FA, BacT/Alert SA, Bactec Plus Aerobic/F and Bactec Standard Aerobic/F bottles. Compared bottles were inoculated at the same time with the identical suspension of bacterial strain. All bottles detected bacterial pathogens even in the case of very low number of inoculated bacteria. The differences of TTD were detected between the bottles of compared hemocultivation systems. Bactec Plus Aerobic/F system is faster in the detection of the members of family Enterobacteriaceae at 1-3 hours, BacT/Aert FA system is faster in the detection of coagulase-negative staphylococci. Most difference was detected at Pseudomanas stutzeri, where the detection in BacT/Alert FA bottles was at 15 hours faster in opposite of Bactec Plus Aerobic/F bottles. In the bottles without sorbent Staphylococcus aureus and Streptococcus sanqui were detected faster in the system Bactec Standard Aerobic/F. The bottles BacT/Alert SA detected faster skin corynebacteria. Detected differences have not a practical importance for the blood stream infection diagnostics.

[Quantitative microbiological diagnostic method of intravascular catheters infection using the BacT/Alert SA bottles]. / Metoda kvantitativní mikrobiologické diagnostiky infekce cévních katetru vyuzívající lahvicky BacT/Alert SA.

OBJECTIVE: The study describes a method of quantitatively examining vascular catheters with the aid of hemocultural devices BacT/Alert. MATERIAL AND METHODS: The amount of bacteria present on the surface of the vascular catheters was determined based on the time to detection (TTD) in hemocultural vials inoculated with bacterial suspension stirred off the catheter surface. RESULTS: A total number of 348 vascular catheters was examined with this new method. Positive cultures were detected in 26 (7.5 %) catheters. Accordance to the results of microbiological catheter examination with clinical condition of the patient was found in 93.1 %. False positivity occurred in 1.1 % (4) and false negativity in 5.7 % (20) of cases. On the basis of clinical symptoms 42 cases of catheter sepsis were diagnosed out of which 22 (52.4 %) positive microbiological quantitative examinations of vascular catheters were established. The most frequent pathogen was coagulase negative staphylococci. CONCLUSIONS: The new method, when compared with present methods, is simpler, faster and able to detect the most frequent agent of catheter infection.

Oriented immobilization of chymotrypsin by use of suitable antibodies coupled to a nonporous solid support.

In order to eliminate the kinetic limitation of chymotryptic hydrolysis of proteins due to diffusion, nonporous hydroxyalkyl methacrylate solid support was developed and used for oriented immobilization of chymotrypsin by means of suitable polyclonal antibodies. Nonporous microspheres were prepared by dispersion copolymerization of 2-hydroxyethyl methacrylate and ethylene dimethacrylate in an alcohol-toluene mixture stabilized with cellulose acetate butyrate. The resulting particles were 1.2 microm in diameter and possessed narrow size distribution. After modification with adipic acid dihydrazide they contained 2 micromol of reactive groups available for coupling of anti-chymotrypsin antibodies. Prepared immunosorbent adsorbed 166.7 microg of chymotrypsin per 1 g of dry carrier. Immobilized chymotrypsin retained practically 100% of its native proteolytic activity. Kinetic parameters of catalysis by chymotrypsin immobilized via this way were improved due to the good steric accessibility of the enzyme active site for high-molecular-mass substrates, when digestion of proteins in batch experiments was used.

[The effect of selected antibiotics on microorganisms contaminating boar ejaculate]. / Ucinnost vybraných antibiotik na mikroorganismy kontaminující ejakuláty kancu.

The occurrence of microorganisms, including their total counts in boar native ejaculates, was investigated in two stages; the objective of this investigation also was to determine contamination after the sperms were treated with diluents containing the antibiotics ampicillin, gentamycin, apramycin, cefoxitin, or antibiotic combinations penicillin + streptomycin, ampicillin + cefoxitin, gentamycin + cefoxitin and ampicillin + gentamycin. The representation of bacterial species and total counts of microbes in 1 ml diluted sperm stored at a temperature of about 18 degrees C were determined in 24, 48 and 72 h after dilution. The microorganisms were cultivated from all native ejaculates. Proteus sp. (63.3%) and Pseudomonas aeruginosa (51.5% of the total number of examined samples) were the most frequent species. The number of contaminated diluted ejaculates ranged from 12.5 to 95.8% in 24 h after dilution, from 12.5 to 98.5% in 48 h and from 16.8 to 95.8% of the total number of examined ejaculates in 72 h. The occurrence of microorganisms correlated mostly with the efficiency spectrum of the antibiotics or their combinations. The average counts of microorganisms in 1 ml of native ejaculate made 2,363,000 in stage I and 1,472,108 in stage II. The highest average counts in 1 ml of diluted sperm were found in ejaculates containing cefoxitin and apramycin. Gentamycin was the most effective antibiotic used as a sole component (average counts of microorganisms CPM in 1 ml were 416 in 24 h, 955 in 48 h and 2260 in 72 h after dilution); ampicillin and gentamycin were the most efficient combination (14--20--21). This combination exerted very good effects also on Proteus sp. and Pseudomonas aeruginosa.

[Serological diagnosis of the species Haemophilus equigenitalis using the rapid agglutination and coagglutination method]. / Sérologická diagnostika druhu Haemophilus equigenitalis metodou rychlé aglutinace a koaglutinace.

The method of rapid slide agglutination and coagglutination was tested in the detection of Haemophilus equigenitalis (Taylorella equigenitalis)--the causal agent of contagious equine metritis (CEM). It was demonstrated that both methods were suitable for the serological diagnosis of the species under study. The antisera obtained from rabbits immunized with Haemophilus equigenitalis strains treated in different ways were specific, but with different antibody titres. When cross reactions with other species of microorganisms were verified, the antisera did not react with any of the strains, even after binding them to protein A of the positive strain Staphylococcus aureus--Cowan I. Coagglutination was much more rapid and pronounced than the ordinary rapid agglutination test. It was characterized by a low consumption of specific antiserum. The specific antibodies bound to staphylococci were kept at the temperature of 4 degrees C for several months without losing agglutinin activity.

[Microbial population of the preputial sac in young bulls]. / Mikrobiální osídlení prepuciálního vaku mladých býcku.

The microbial population of the praeputial sac was studied in a group of ten young bulls housed in one section of the rearing farm in the age period from 2 to 14 months when they were transferred to A. I. stations. As to currently occurring microflora, Proteus sp. and Pseudomonas aeruginosa were isolated most frequently. The remaining micro-organisms isolated during the study included E. coli, non-haemolytic and viridizing streptococci, Staphylococcus epidermidis, micrococci, aerobic sporulating bacteria, saprophytic corynebacteria snd gamma-negative non-fermenting rods. Campylobacter foetus subsp. foetus was not detected and the same applies to the other species of this genus (Campylobacter sp.). When the bullocks were transferred to the rearing farm, the mycoplasms were no longer isolated from the praeputial mucous membrane. Mycoplasms were determined in all the studied animals after six months' stay in group. The isolated strains were identified as M. bovigenitalium by the epiimmunofluorescence method.

[Results of bacteriological and cytological studies of uterine lavages in cows from herds with fertility disorders]. / Výsledky bakteriologického a cytologického vysetrování delozních lavází krav ve stádech s poruchami fertility

A cytological and bacteriological examination of uterine lavages of 264 cows from herds with fertility disorders (without convincing pathological findings) helped to determine the clinical diagnosis in a more exact way. In 41.67% of the cases, mucosal metritis was cytologically proved. Bacterial contamination of the urerine medium was observed in 83.71% of the cases. The result of bacteriological examinations of uterine lavage and cervical smear brought about various findings in 77.27% of the cases. The bacteriological contamination rate of the uterine medium without metritis was highest in the follicular phase. Both the cows suffering from metritis and in cows without any changes due to metritis, common, conditionally pathogenic microflora was found (with the exception of several cases) the etiocausal effect of which on the metritis origin and decreased fertility could not be, in general and for certain, proved.

[Effect of long-term freezing preservation on the level of bacterial contamination of the sperm]. / Vliv dlouhodobé konzervace zmrazováním na hladinu bakteriální kontaminace spermatu

Fourty-five ejaculates of breeding bulls were examined at a breeding station in order to study the contamination level of sperm after ejaculation, after thinning, after finished equilibration, after freezing, and after three months after placement in liquid nitrogen at -- 196 degrees C. The amount of germs in sperm was found to increase rapidly in the course of examination and thinning at laboratory temperature. The average number of 4,149 germs increased to 9,729. During equilibration the number of germs dropped to 3,670, after freezing it decreased to 2,442, and after three months of storage in liquid nitrogen the contamination level was 901 germs. All values were converted to the volume of the insemination dose of 0.2 ml. Incubation at 37 degrees C lasted 48 hours. All differences were statistically significant. The freezing of thinned sperm significantly reduced the level of microflora.