I think only the most radical people that do believe in natural medicine throw away more modern methods if needed.
I suspect we cannot fully understand natural medicines by looking at one cure for one illness. I think natural health and thereby natural medicines is an approach to healthy living more than the modern approach of treating symptom at a time.
In natural medicines and in traditional Asian medicines the approach is more along the thinking that something in the environment has upset the natural balance in the animal, causing a breakdown in the immune system.
That means looking at the soil, the grass , the water, environmental toxins, mineral balances, etc. the animal is exposed to first to see what is out of balance. Fix that and you fix the immune system breakdown in the animal. Natural medicines, herbs are designed to strengthen the weakness in the immune system caused by imbalances. These cures are often not quick fixes, but rather aids to helping the body heal itself. That may be one reason why it is so often viewed as unsuccessful. It takes time to correct imbalances. It takes time to find the imbalances.
It is not a cure-all system. If a system was born out of wack it will not be fixed, such as a heart defect and the like. Balancing the environment might, however, prevent one like problem from being born that way in the future.
The modern medicine world has only had Penicillan since just after WWI or is it WWII. We had sulfa drugs. Before that the world had natural medicines. Everyone and every animal was not dropping dead all of the time. Do a little geneology and you will see your ancestors often lived longer than we do now. Ages of 80,90 and 100 were certainly not unheard of. Not only that but they worked without mechanical horsepower and had 14 children.
All the labor saving devices may not have been such a gift in the long run. It appears physical hardwork and having enough but not too much went a long way toward health. Pesticides, toxins and the like are a relatively recent phenomenon.
I'm just not sure we know how to study affects of natural medicines in Universities and such without guarenteeing skewed results. I know of a woman who raises goats and worms with garlic mixed in yogurt. She swears by it and has used it for years. Yet she readily admits this only works for the goats born there. Animals brought in that have previously been treated with anhelminics do not respond to her natural treatments so she had learned she will need to wait for the offspring to treat them her natural way. Pretty interesting.
The Complete Herbal Handbook For Farm and Stable by Juliette de Bairacli Levy is a recommended book for herbal type treatments. Unfortunately the Author is English and the herbs are not always what is common to the USA. It was recommended to me by a veternarian who combines traditional western medicine with natural medicine. I have not had a chance to try it because I haven't had a sick animal since I bought it, except a dog with a large bone spur on her spine which I'm pretty sure it won't help with that, except maybe with pain.
It may all be hocus pocus I don't know, but the world did something in earlier times and survived.
The one thing I do believe is the less we use medicines and wormers the longer they will remain effective for us when we truly need them.
Melissa