VDL Lab Section | General Sample Retention Policy |
| Bacteriology | Submitted samples are retained for approximately two weeks from the date they are received. Significant isolates are stored for 12 months. |
| Electron Microscopy | Samples submitted for negative staining will be retained for 3 days at 4 degrees Celsius, processed samples on grids will be retained for 5 weeks at room temperature. Samples submitted for Ultrastructural diagnoses will be processed and retained in resin blocks along with corresponding semi-thin sections and thin sections for 5 years at room temperature. |
| Endocrinology | Routine serum/plasma samples are stored (refrigerated or frozen) for at least one week after test completion before being discarded or utilized by the laboratory. Exception: As required, OFA serum samples are stored frozen for six months. |
| Histology | Fixed, paraffin-embedded tissue samples, and the corresponding stained micro slides are retained for 5 years at room temperature. |
| Immunohistochemistry | Fixed, paraffin-embedded tissue samples, and the corresponding stained micro slides are retained for 5 years at room temperature. Exception: Samples submitted for TSE testing and testing negative are retained for 3 years at room temperature. Samples testing positive for TSE are forwarded to the NVSL/USDA Laboratory in Ames, IA. |
| Udder Health | All submitted samples are retained for two weeks from the date received. |
| Minnesota Poultry Testing Laboratory | Avian serology samples are retained for 7 days after completion of testing. |
| Molecular Bacteriology | All samples are maintained in the refrigerator for two weeks after the week of testing, and then may be discarded or utilized by the laboratory. Note: swabs may be destroyed in the extraction process. |
| Molecular Diagnostics | Original material is kept for a minimum of two weeks. Tissue homogenate supernatants positive for PRRS, BVD and PCV2 are kept for one year. |
| Necropsy | Fresh tissues: various specimens, selected at the discretion of the pathologist, may be retained in refrigeration for 10 days.
Fixed tissues: retained for 20 days.
Large animal remains: ordinarily will not be held after necropsy, but if requested, will be held no more than 15 days.
Companion animals and horses: see the information on handling of animal remains in our necropsy guidelines. |
| Parasitology | Samples are retained for 7 days after submission. |
| Serology | Serum samples are retained for 30 days after completion of testing. |
| Virology | All tissue/serum/swab samples that have requests for virus isolation are stored for 2 years. Samples that are positive in virus isolation are stored indefinitely. |
