The present invention relates to a composition comprising IgY antibodies against at least two different fungi, the use of the composition for the preparation of a pharmaceutical especially for prophylaxis and / or therapy of all kinds of fungal infections, such as conditions caused by organisms belonging to the Candida genus or Aspergillus genus, especially of fungi that are less sensitive to antimycotica and a diagnotstic method using the IgY antibodies. Further it relates to immunisation of birds with a combination of at least two different species of fungi to the Candida genus or Aspergillus genus and a diagnostic method for fungi. It also relates to relates to a novel method for treatment and / or prophylaxis of fungal infections, especially infections by fungi which have lowered sensitivity or resistance to antimycotics. The method is both safe and effective. This is achieved by using IgY directed against fungi, in particular against Candida species, which have a lowered sensitivity or resistance against antimycotics. The specific IgY has been obtained by hyper immunising birds with one or several fungi as antigen in order to stimulate the production of immune globulins (IgY) against such fungi. The present invention also relates to a pharmaceutical product from eggs of birds containing immune globulin or a fragment thereof, which can be combined with other preparations, nutritients or pharmaceuticals for simultaneous, separate or sequential use in the prophylaxis or therapy of gastrointestinal infections in newborn infants.