The phrase "different strains" refers to variations or types within a particular category or group. It suggests that there are different versions or forms of something, each with its own unique characteristics. Full definition
He found himself confronting at least a dozen jars full of different strains of weed. (entrepreneur.com)
* The fermented veggies are also a particularly powerful source of probiotics with different strains from what you get in yogurt or kefir for different health benefits for your digestive system and immune system. (truthaboutabs.com)
Some infectious agents exist in different strains or evolve into new strains that are not directly covered by the vaccines given. (springcreekanimalhospital.com)