Also found in: Medical.
a biological preparation used to test for the presence of glanders in horses, donkeys, and mules. It was developed by the Russian researchers Kh. I. Gel’man and O. I. Kal’ning, independently of one another, in 1891. Mallein is prepared from a typical strain of the glanders microorganism Bacterium mallei. It is applied in three principal ways: ophthalmically, subcutaneously, or intradermally.