Objective—To compare isolates of Rhodococcus
equi on the basis of geographic source and virulence
status by use of pulsed-field gel electrophoresis
Sample Population—290 isolates of R equi(218 virulent
isolates from foals and 72 avirulent isolates from
feces, soil, and respiratory tract samples) obtained
between 1985 and 2000 from horses and horse farms
from 4 countries.
Procedure—DNA from isolates was digested with
the restriction enzyme AseI and tested by use of
PFGE. Products were analyzed for similarities in banding
patterns by use of dendrograms. A similarity
matrix was constructed for isolates, and the matrix
was tested for nonrandom distributions of similarity
values with respect to groupings of interest.
Results—There was little grouping of isolates on the
basis of country, virulence status, or region within
Texas. Isolates of R equi were generally < 80% similar,
as determined by use of PFGE. Isolates from the
same farm generally were rarely of the same strain.
Conclusions and Clinical Relevance—Considerable
chromosomal variability exists among isolates of R
equi obtained from the same farm, sites within Texas,
or among countries from various continents. Only
rarely will it be possible to link infections to a given
site or region on the basis of analysis of isolates by
use of PFGE of chromosomal DNA. (Am J Vet Res 2003;64:153–161)
OBJECTIVE To develop and evaluate a pyramid training method for teaching techniques for collection of diagnostic samples from swine.
DESIGN Experimental trial.
SAMPLE 45 veterinary students.
PROCEDURES Participants went through a preinstruction assessment to determine their familiarity with the equipment needed and techniques used to collect samples of blood, nasal secretions, feces, and oral fluid from pigs. Participants were then shown a series of videos illustrating the correct equipment and techniques for collecting samples and were provided hands-on pyramid-based instruction wherein a single swine veterinarian trained 2 or 3 participants on each of the techniques and each of those participants, in turn, trained additional participants. Additional assessments were performed after the instruction was completed.
RESULTS Following the instruction phase, percentages of participants able to collect adequate samples of blood, nasal secretions, feces, and oral fluid increased, as did scores on a written quiz assessing participants' ability to identify the correct equipment, positioning, and procedures for collection of samples.
CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the pyramid training method may be a feasible way to rapidly increase diagnostic sampling capacity during an emergency veterinary response to a swine disease outbreak.