An exemplary embodiment providing one or more improvements includes feeding animals with probiotic microbes encapsulated in a mixture of xanthan gum and chitosan, or in gelatin, specifically Pediococcus acidilactici and Saccharomyces boulardii. Such encapsulation protects the viability of the probiotic microbes against unfavorable temperatures. An exemplary embodiment providing one or more improvements includes methods of using viable probiotics in therapy of birds and mammals infected with infectious diseases. Probiotics acted as adjuvants in stimulating antibody reaction and stimulated a cellular immunity response. In particular, probiotics were shown to reduce the number of viable oocytes from fecal samples, stimulate antibody production, and stimulate of proliferation of splenocytes in chickens infected with Elimeria. In addition, probiotics were shown to relieve symptoms of parvovirus infection in dogs.