Source: IOWA STATE UNIVERSITY submitted to
CAUSES OF BARN COUGH IN LAMBS
Sponsoring Institution
Cooperating Schools of Veterinary Medicine
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0205523
Grant No.
(N/A)
Project No.
IOWV-ROSENBUSCH
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Aug 1, 2005
Project End Date
Jul 30, 2008
Grant Year
(N/A)
Project Director
Rosenbusch, R. F.
Recipient Organization
IOWA STATE UNIVERSITY
S. AND 16TH ELWOOD
AMES,IA 50011
Performing Department
VETERINARY MEDICINE
Non Technical Summary
Chronic cough is a problem for lamb producers. The project seeks to determine if Bordetella-like bacteria are involved in chronic cough in IA lambs.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3113610110060%
3113610117010%
3114010110010%
3114010117010%
7223610117010%
Goals / Objectives
We will search for Bordetella-like bacteria in throats of IA sheep with cronic cough. We will also search for genes of persistent cough bacteria in nasal bacteria from these sheep. If any of these are found, we will determine the respiratory pathogenicity of these bacteria.
Project Methods
We will obtain pharyngeal tonsil swab samples from sheep with chronic cough and normal sheep. Samples will be cultured for Bordetella, and processed for detection of Bordetella pathogenicity genes. Pathogenic Bordetellas will be inoculated into lambs.

Progress 08/01/05 to 07/30/08

Outputs
OUTPUTS: The objective of the work was to determine if Bordetella-like organisms were responsible or accessory to the cause of chronic cough in Iowa lambs and goat kids. Tonsil swabs from affected and healthy animals were cultured using various types of selective media. Besides noting a previously reported association of this clinical presentation with presence of Mycoplasma ovipneumoniae, isolates of Comamonas testoteroni, a gram negative organism, were also found asssociated with coughing animals, particularly in goat herds. Transcripts of virulence genes of Bordetellas were sought in mRNA extracts from these bacteria. Transcripts for a dermonecrotoxin were detected in C. testosteroni isolates when they were grown under biofilm-inducing conditions. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Research scientists and veterinarians interestede in respiratory disease of domestic sheep and goats. Wildlife scientists and veterinarians interested in respoiratory disease of wild sheep and goat species in North America. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The identification of Comamonas testosteroni as a potential primary cause or secondary agent in chronic cough of sheep and goats is an important intial step in understanding the pathogenesis of this disease. The findings can be used to better understand differences in chronic cough presentations in lambs and goat kids, as well as serve to improve the therapeutic interventions now used o control the disease.

Publications

  • No publications reported this period


Progress 01/01/07 to 12/31/07

Outputs
The objective of the project was to determine if Bordetella-like organisms were the cause of chronic cough in Iowa lambs. Tonsil swabs were cultured from coughing and healthy lambs. Bordetella-like organisms were identified as Comamonas testosteroni by biochemical tests. These isolates were obtained occasionally from flocks with chronic cough, and were more easily recovered from goat herds with chronic cough. A dermonecrotoxin was potentially produced by these bacteria, since RT-PCR demonstrated transcripts for this gene, when the cultures were grown under conditions stimulating biofilm formation in-vitro. No other potential pathogenicity genes of Bordetellas were found in these bacteria.

Impacts
We have identified Bordetella-like bacteria in sheep an dgoats with chronic cough. Interestingly, the species of interest is not identified as within the genus Bordetella but rather Comamonas by standard automated microbial identification systems. Production of one of the three virulence factors used by Bordetellas to cause chronic cough was demonstrated in Comamonas isolates.

Publications

  • No publications reported this period