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Trunk wash procedure

Compiled by Willem Schaftenaar


The trunk wash procedure was developed as a method for diagnosing tuberculosis or the detection of Elephant Endotheliotropic Herpes Virus. This procedure is an active manipulation at the elephant trunk, which can be performed in free and protected contact systems in non-immobilized elephants after they are conditioned for this procedure. The principle is that a sterile 0,9% saline solution (approx. 100 ml) is injected in each nostril of the trunk. The trunk has to be lifted actively by the elephant or passively by the keeper so that the solution is running up to the base of the trunk. The mixture of the solution and trunk mucus is collected in sterile plastic bags by active blowing of the elephant through its trunk (training required). The staff should protect themselves against spilling trunk content into their face. A full trunk wash procedure requires 3 different trunk washes performed within a period of 7 days. Each sample must be sealed and stored at 4°C. Depending on the quality of the samples, the diagnostic lab can decide to pool the samples for culture/PCR. Samples must be shipped to the TB-diagnostic lab immediately after the 3-rd sample has been taken. The maximum storage period at 4°C is 7 days.  NB: follow the EU guideline for shipment of potentially hazardous biomaterials. For the (q)PCR detection of EEHV, the sample can be shipped directly or kept frozen at -20°C until shipment. 

Trunk wash in a non-contact situation requires a full anesthesia of the elephant and a portable fluid pump and sucking system, which allows the operation under sterile condition. The external pump and sucking system will be connected to a sterile PVC tube (1 cm diameter, with distance markers) with a length of approx. 2 meter. The amount of sterile solution and the collection bag are like described before. In non-contact situations, a bronchoalveolar lavage (BAL) under standing sedation is the preferred procedure.

Training for a trunkwash procedure

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