A self-filling micropipette for the isolation of single coccidial oocysts

A disposable, self-filling micropipette is described for the isolation of single oocysts of chicken coccidia from laboratory stocks. A sterile 1 microliter capillary tube is mounted, using sealing wax, into the narrower end of a broken-off Pasteur pipette. This micropipette is pushed into one end of a 60 cm length of flexible plastic tubing and a 5 cm glass tube is pushed into the other end. The apparatus is used by holding the glass tube in one's mouth, maintaining a positive pressure in the buccal cavity, while the tip of the capillary tube in the micropipette is juxtaposed with a single oocyst in a diluted stock on a cavity slide, observed under a microscope objective. A sudden release of the positive pressure causes the chosen oocyst to be instantaneously taken up into the capillary tube. Using the tube again, the oocyst is then blown out onto a piece of 'Cellophane' which is placed in a gelatine capsule. The capsule is administered to a chick in a plastic-film isolator.