BTS Boar Semen Extender (1 to 3-Day Extender) - RP BTS Extender (Beltsville Thawing Solution) is a short-term 0-3 day swine semen extender originally developed by the USDA at Beltsville, Maryland.RP BTS Extender is available in 1L (#101101), 3.5L (#101105) and 100L (#101110) sizes for ease of mixing. Preparation: Mix and dissolve contents according to instructions with sterile, distilled water at 32C-38C (90-100F).Allow the pH to stabilize for 20 minutes before using to extend semen. Application: Ensure prior to extension that freshly collected boar semen and extender are adjusted to the same temperature.Storage and shipment of the extended semen should be 16-18C (61-64F). Quality Control: Warm extended semen to 37C (98F) for a minimum of 20 minutes prior to motility evaluation. Storage: Store in a dry and dark environment below 15C (60F). Warning: Keep out of reach of children, Not for human or animal consumption or drug or clinical use. Not for injection.