we get seaweed off the beach and soak it and dry it, we give it in bunches for our chickens to peck at, especially youngsters that are still inside. wev given it to quails and rabbits aswell. i did put a few bunches out for pigs but dont think they ate it. it mite have to be ground before they would eat it. i was aware that pigs have salt poisoning issues though.
also we bought poultry spice - which appears to be mainly spice powders such as turmeric etc, so i dont think it would be to difficult to make it yourself either.