A method of injecting a plurality of bird eggs comprises: (a) orienting a plurality of avian eggs in a predetermined position; (b) forming an opening in the shell of each of the eggs; (c) extending an elongate delivery device through each of the openings and into the eggs, each of the delivery devices comprising a
detector and an injection needle, with the injection needle having a lumen formed therein; (d) detecting with the
detector information from the interior of each of the plurality of eggs; and (e) injecting a substance into each of the plurality of eggs through the lumen of said injection needle. The detected information can be used for a variety of purposes, including adjusting the
depth of penetration of the injection needle to more precisely control the location of the injection, identifying the gender of the eggs for subsequent sorting of the eggs, distinguishing viable from non-viable eggs, etc. When used for controlling depth penetration, the method positions the needle tip for any purpose, including withdrawing biological material as well as injecting substances. Apparatus, particularly high-speed apparatus, for carrying out the method is also disclosed.