http://www.drugs.com/pro/terramycin.html
Terramycin is indicated as a treatment for various bacteria, but I've never seen anything where it's considered indicated for parasites. Could you please let me know where you found that so if I'm wrong I can correct my thinking?
Sulfamides (Sulfamethazine Sodium for example) are cross-over antibiotics that also effect other micro-organisms such as protazoa. But even it doesn't effect worms.
Oil vitamins depend on oil/fats in the diet to be absorbed. BUt there are some studies that show that vitamin E absorbtion can be increased if given as an oil form.
The alternative is to give vitamins in the water exposed to light and sitting out for a day hoping they work. To me, that's not very efficient. So that's why I recommend using something that happens more quickly so you know that the light-sensitive vitamins are getting in there combined with food (which there are also studies showing that supplementation in conjunction with food is more efficient than that with liquid and an empty stomach, which many sick birds have, than water consumption).
So each poultry owner is entitled to choose his own way. But personally when I recommend something, and there's a possible nutritional need that needs to be addressed immediately (rather than just maintenance), I recommend the one that I've been read about to be the more effective choice.
I really am interested in your tetracycline sources about parasite indication so that I can learn more. In the mean time, I think you and I differ on how this should be handled and it is after all your bird. I wish you the absolute best of luck with her and your flock. Thank you for taking the time to read my posts.