The ideal feeding period for supplements differs depending on the purpose and composition of the supplements.
For instance, probiotics are best given before a meal, as an empty stomach will allow them to reach the gut more easily. Meanwhile, supplements containing oily substances, like omega-3 supplements, or amino acids may upset your cat’s stomachs and cause them pain when taken on an empty stomach. Such supplements should be given after a meal.
Many antioxidants contain fat-soluble ingredients, which means they are more easily absorbed with food. As such, they are also better given after a meal.
In summation, probiotics are best given before a meal, while omega-3, amino acids, and antioxidants are best given after your cats have been fed.