The probiotics are grown (fermented) on substrates, specifically for the purpose of food use. They are not derived/extracted from fish or other sources. Please note that the use of probiotics in a dry extruded pet food without special licensing, as in the product you are using, is a violation of patent laws.
The vitamins and minerals are produced synthetically or through fermentation, as are all vitamin supplements and fortifiers. Some are contained in the fish and chicken fat.
Also, consider signing up for our free program, The 100 Pet Health Truths. The 100 Pet Health Truths will equip you to become a discerning and educated pet owner. We have condensed Dr. Wysong's 30 years of health wisdom into 100 short and easy messages enhanced with fun graphics and videos. You will also receive coupons totaling $100 for free Wysong products interspersed throughout the program.