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| | ==Diagnosis== | | ==Diagnosis== |
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| − | merck A presumptive diagnosis of enterotoxemia is based on sudden, convulsive deaths in lambs on carbohydrate-rich feed. Smears of intestinal contents reveal many short, thick gram-positive rods. Confirmation requires demonstration of ɛ toxin in the small-intestinal fluid. Fluid, not ingesta, should be collected in a sterile vial within a few hours after death and sent under refrigeration to a laboratory for toxin identification. Chloroform, added at 1 drop for each 10 mL of intestinal fluid, will stabilize any toxin present. Although immunologic tests have been developed to replace the traditional mouse assay for detection of toxin, they are less sensitive than the mouse assay. A PCR protocol for detection of the gene for ɛ toxin is effective in identifying isolates as either type B or D.
| + | A presumptive diagnosis of pulpy kidney can be made based on a history of sudden deaths in lambs recently introduced to carbohydrate-rich feed. If animals are seen before they die, certain clinical signs may be suggestive of pulpy kidney, and post-mortem examination may also aid diagnosis. Laboratory tests support, but do not confirm, a diagnosis of pulpy kidney. |
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| − | * Location of the organism in the gut contents is not helpful, since it is always present (as a commensal).
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| − | ** Therefore, diagnosis is by location of the toxin in the gut contents.
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| − | * Toxin is tested for by administering filtered intestinal fluid intravenously to a mouse (mouse protection test).
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| − | ** If the toxin is present, the mouse should die within minutes or hours.
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| − | ** Another mouse can be protected from the effect of the toxin with a specific antibody.
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| − | * An ELISA test is also possible.
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| − | ** However, an ELISA is often too sensitive as the toxin can be present in the normal sheep gut and the ELISA can pick this up.
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| | ===Clinical Signs=== | | ===Clinical Signs=== |
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| | ===Laboratory Tests=== | | ===Laboratory Tests=== |
| − | | + | merk Smears of intestinal contents reveal many short, thick gram-positive rods. Confirmation requires demonstration of ɛ toxin in the small-intestinal fluid. Fluid, not ingesta, should be collected in a sterile vial within a few hours after death and sent under refrigeration to a laboratory for toxin identification. Chloroform, added at 1 drop for each 10 mL of intestinal fluid, will stabilize any toxin present. Although immunologic tests have been developed to replace the traditional mouse assay for detection of toxin, they are less sensitive than the mouse assay. A PCR protocol for detection of the gene for ɛ toxin is effective in identifying isolates as either type B or D. |
| | ===Pathology=== | | ===Pathology=== |
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