The present invention provides an optical multiplexerdemultiplexer that can be smaller in size and higher in Q-factor or efficiency. The present invention additionally relates to methods of promoting animal growth and inhibiting parasitic infectioninfestation with these compositions, as well as methods of preparing such compositions. A mathematical optimization algorithm is used to select a sequence in which the plurality of decisions are to be considered. The optical components are fixed in position by soldering, and the retractable portions allow for the jig stencil to move relative to the fixed components to avoid misalignment of the OSA components during cooling.