Study Aims and Objectives:
The primary aims of this study are:
· to establish the extent of environmental burden of virulent R. equi in the soil at farms affected with pneumonia caused by this bacterium relative to farms that have not been affected;
· to determine whether a higher concentration of virulent R. equi in soil is a cause (i.e., occurs prior to the onset of pneumonia among foals) or effect (ie, occurs because sick foals have contaminated their environment) of pneumonia caused by R. equi; and
· to determine whether there is an association between the concentration of R. equi found in soil samples from affected farms and the incidence of pneumonia attributed to R. equi at affected farms.
Our long-term objective with respect
to R. equi is to better understand the epidemiology of infection
and associated disease so that we can make advances in preventing the
disease. Specifically, we hope to establish whether soil in pastures
and paddocks is an important source of infection for foals. Another long-term
objective of this project is to establish a network of practitioners willing
and interested in collaborating on a various projects of importance to
equine health in
Instructions for Participation
A. FIRST, SELECT 2 FARMS TO BE INCLUDED IN THE STUDY
1. Select an "AFFECTED FARM" that meets the following criteria:
· You expect the farm to have foals affected with R. equi pneumonia during 2006;
· The farm will have at least 10 foals born at the farm during 2006 and 2007;
· The farm had at least 2 foals with R. equi pneumonia (as defined below) born and raised on the farm during at least 3 of the past 5 years
· For this study, a foal affected with R. equi pneumonia will be defined as a 3-week- to 6- month-old foal with either (please refer to the flow chart on the next page):
a) clinical signs of pneumonia (tachypnea, fever, nasal discharge, cough) and from which R. equi was isolated from a tracheobronchial aspirate (TBA) or postmortem lung specimen; or,
b) clinical signs of pneumonia and at least 2 of the following: i. multifocal pulmonary opacities on thoracic radiographs; ii. ultrasonographically visible pulmonary abscesses; iii. cytologically-visible Gram-positive intracellular coccobacilli on TBA specimens; or, iv. another foal at the farm meeting the first definition of an affected foal (i.e., signs of pneumonia and R. equi isolated from a TBA).
2. Select an "UNAFFECTED FARM" that meets the following criteria:
· You do not expect the farm to have foals affected with R. equi pneumonia;
· The farm will have at least 10 foals born at the farm during 2006 and 2007;
· The farm will have had no foals with R. equi pneumonia (as defined below) born and raised on the farm during any of the past 5 years;
· The farm will have similar resources as the affected farm (i.e., you would be able to implement similar approaches to prevention, screening, and treatment if any foals developed R. equi as you would for the affected farm)
B. SPECIMEN AND DATA COLLECTION
1. What to collect:
a. Soil samples: from 1 farm likely to be affected by R. equi pneumonia and 1 farm without history of R. equi pneumonia (as previously defined)
b. Data: Please complete a study data form for each farm when it is sent to you later
2. When to collect:
a. Soil samples: Please collect soil samples on or around (within 5 days) the following dates:
i. January 15, 2006 v. January 15, 2007
ii. March 15, 2006 vi. March 15, 2007
iii. July 15, 2006 vii. July 15, 2007
iv. November 15, 2006 viii. November 15, 2007
b. Data: Please complete a data form for the study and return with the November soil samples each year. These forms will be mailed to you in October of each year.
i. November 15, 2006 ii. November 15, 2007
3. Where to collect:
a. Soil samples:
i. from 3 locations in paddocks used to house foals at each farm you contribute
ii. at a given farm, please always use the same 3 locations at each of the different sampling times
iii. whenever possible, please collect soil samples from areas where foals are likely to congregate (such as near water troughs, feeders, etc.)
iv. each year, you will collect a total of 24 samples (3 samples per farm on 4 occasions (12 soil samples/farm) for 2 farms = 24)
b. Data: Please complete the data form at the location of your choice and return this form for a given year with the November soil samples. Each year you will complete at least 2 forms (1 for each farm you contribute)
4. How to collect:
a. Soil samples:
i. Please use the spoon provided to collect soil from the surface (no deeper than 2 inches from the surface) of the area you are sampling.
ii. PLEASE DO NOT USE THE SPOON FROM ONE FARM TO COLLECT SAMPLES FROM ANOTHER FARM. PLEASE SAVE THE SPOON. PLEASE WIPE THE SPOON WITH ENCLOSED ALCOHOL WIPES AND ALLOW TO DRY BETWEEN EACH SITE.
iii. For each of the 3 sites at a farm, please place 3 spoonfuls of soil in one of the plastic sacks (whirl-paks) with labels that we have provided to you (you will place soil in 3 sacks per farm at each sampling time). Please label each sack with the date, your name, the farm identifier, the farm status (i.e., "affected" or "unaffected"), and a description of the location from where the soil was collected.
iv. Please return the soil samples for a given month from the 2 farms you are contributing by courier using the enclosed airbills. PLEASE SUBMIT THE SAMPLES AS SOON AS POSSIBLE AND WITHIN 24 HOURS OF COLLECTION; PLEASE REFRIGERATE/COOL SOIL SAMPLES UNTIL SHIPPING.
b. Data form:
i. A data form for each farm you contribute will be mailed to you in the fall of each year. Please complete the form and return it with the November soil samples for that farm.
ii. The following data for each farm will be requested:
· Total number of foals born at the farm (or farm unit/division);
· Total number of foals born at the farm to resident mares;
· Total number of foals that remained at the farm through weaning;
· Total number of foals born to resident mares that remained at the farm through weaning;
· Total number of foals diagnosed with R. equi pneumonia at the farm;
· Total number of foals born to resident mares diagnosed with R. equi pneumonia;
· Estimated total acreage used to house mares and foals at the farm;
· Number of years the farm was used for horse breeding;
· Date of onset of the earliest case of R. equi pneumonia at the farm;
· Methods used to diagnose R. equi pneumonia among foals at the farm (i.e., microbiologic culture of tracheobronchial fluid, radiography, serology, clinical signs, etc.).
