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Molecular pathogenesis of brucellosis-unlocking the secrets of host specificity - SE0308

Description
Objective: To establish target residues and validated methods of analysis for natural steriod hormones in cattle, enabling discrimination between concentrations within the normal range from those resulting from illegal administration.

Justification: Policy and scientific objectives, as described in the ROAME A for Veterinary Medicines (Residues in meat and animal products), are addressed in relation to development, validation and application of analytical nethods enabling surveillance for illicit administration of natural steroid hormones in cattle.

Approach and uses: If successful the proposed project will deliver the following:-
- A series of targeted steriods to be monitored to detect abuse of natural steroid hormones.

-Validated recombinant receptor methods for the generic extraction and screening of receptor-binding natural androgens.

- LC and GC-MS methods (as appropriate) for the quantitative and confirmatory multi-residue analysis of target compounds in body fluids (bile, urine and plasma).

- The normal range of concentrations of target residues in specified categories of catrtle and associated threshold values and a demonstration of the efficacy of applying thresholds to the identification of treated animals.

An analytical strategy for the regulatory control o naturla androgen abuse, proposed for application within the National Surveillance Scheme.
Objective
01- Confirmation of plasma endogenous oestrogen concentrations by RCBA/
02- Optimisation and validation of RCBA for naturak androgens, xenoandrogens and their metabolities.
03- Assay of biological samples; copmparison of recombinant yeast androgen assay and GCMS.
04- Investigation of conditions for receptor expression and immobilisation.
05- Development and application of receptor affinity chromatography for androgens.
06: Qualitative and quantitative GC-MS analysis of extracts of urine, bile and plasma samples from statistically meaningful numbers of cattle from various categories (steers and heifers, or other cattle, as reprentative of the population presented at the slaughter house for human consumption)
07- Qualitative and quantitative APCI-LC/MSMS analysis of extracts of biological fluids from the bovine where GC-MS analysis is not applicable or where LC-MSMS analysis is more suitable.
08: Collation and statistical treatment of the data to develop strategies for regulatory control of the endogenous hormones.
09: Demonstration of the effectiveness of the strategies using post-administration samples.
Project Documents
• Final Report : Molecular pathogenesis of Brucellosis- unlocking the secrets of host specificity   (365k)
Time-Scale and Cost
From: 2003

To: 2006

Cost: £544,730
Contractor / Funded Organisations
Veterinary Laboratories Agency
Keywords
Animal Diseases              
Animal Health              
Brucellosis              
Pathogenesis              
Plants and Animals              
Fields of Study
Animal Health